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Sharif S, Tang J. Potassium Derangements: A Pathophysiological Review, Diagnostic Approach, and Clinical Management. Physiology (Bethesda) 2022. [DOI: 10.5772/intechopen.103016] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022] Open
Abstract
Potassium is an essential cation critical in fluid and electrolyte balance, acid–base regulation, and neuromuscular functions. The normal serum potassium is kept within a narrow range of 3.5–5.2 meq/L while the intracellular concentration is approximately 140–150 meq/L. The total body potassium is about 45–55 mmol/kg; thus, a 70 kg male has an estimated ~136 g and 60 kg female has ~117 g of potassium. In total, 98% of the total body potassium is intracellular. Skeletal muscle contains ~80% of body potassium stores. The ratio of intracellular to extracellular potassium concentration (Ki/Ke) maintained by Na+/K+ ATPase determines the resting membrane potential. Disturbances of potassium homeostasis lead to hypo- and hyperkalemia, which if severe, can be life-threatening. Prompt diagnosis and management of these problems are important.
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A Case of Gitelman Syndrome with Hypercalcemia Secondary to Primary Hyperparathyroidism. Case Rep Endocrinol 2022; 2022:1098222. [PMID: 35795477 PMCID: PMC9252710 DOI: 10.1155/2022/1098222] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/21/2021] [Revised: 03/30/2022] [Accepted: 06/13/2022] [Indexed: 11/17/2022] Open
Abstract
Gitelman syndrome is a rare autosomal recessive salt-losing tubulopathy characterized by hypokalemia, hypomagnesemia, hypocalciuria, and secondary hyperaldosteronism. However, hypercalcemia secondary to hypocalciuria is extremely rare during the disease. A 36-year-old normotensive man who suffered a motor vehicle accident was presented with hypokalemia, hypomagnesemia, and mild hypercalcemia. He had a past medical history significant for bipolar depression disorder and a history of chronic atrial fibrillation. He was diagnosed with Gitelman syndrome. However, he was noncompliant with his medications. A laboratory workup revealed hypokalemia, hypomagnesemia, hypercalcemia, and a high parathyroid hormone level. Thorough investigations identified primary hyperparathyroidism as the primary cause of hypercalcemia. To our knowledge, Gitelman syndrome and primary hyperparathyroidism are an extremely rare association that is present in our case.
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Chen SY, Jie N. Gitelman syndrome: A case report. World J Clin Cases 2022; 10:5893-5898. [PMID: 35979117 PMCID: PMC9258353 DOI: 10.12998/wjcc.v10.i17.5893] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/01/2022] [Revised: 02/24/2022] [Accepted: 04/03/2022] [Indexed: 02/06/2023] Open
Abstract
BACKGROUND Gitelman syndrome (GS) is an autosomal recessive salt-losing renal tubulopathy arising from mutations in the thiazide-sensitive Na-Cl cotransporter gene. Due to its low incidence and lack of awareness, GS can be easily misdiagnosed or missed in diagnosis.
CASE SUMMARY A 24-year-old male presented with > 4 years of repeated limb weakness without any treatment. The previous day, the patient was bitten by ants and showed weakness of the lower limbs. The patient had hypokalemia (1.66-2.83 mmol/L), hypomagnesemia (0.4 mmol/L), hypocalciuria (1.51-2.46 mmol/d), metabolic alkalosis (7.47-7.54), normal blood pressure, and increased activity of aldosterone and plasma renin activity (PRA) (PRA 6.4 and 16.45 ng/mL/h and aldosterone 330.64 and 756.82 pg/mL in the supine and upright position, respectively). In addition, SLCI2A3 gene mutation with GS was diagnosed. Oral and intravenous supplementation with potassium and magnesium was initiated. Serum magnesium returned to 0.48 mmol/L and serum potassium returned to 3.08 mmol/L, alleviating the patient’s fatigue symptoms.
CONCLUSION GS should be considered in patients with hypokalemia complicated with hypomagnesemia. Genetic testing is essential to confirm the diagnosis.
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Affiliation(s)
- Shi-Yuan Chen
- Department of Endocrinology, Longhua Central Hospital, Shenzhen 518110, Guangdong Province, China
| | - Ning Jie
- Department of Endocrinology, Longhua Central Hospital, Shenzhen 518110, Guangdong Province, China
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4
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Clinical and Genetic Characterization of Patients with Bartter and Gitelman Syndrome. Int J Mol Sci 2022; 23:ijms23105641. [PMID: 35628451 PMCID: PMC9144947 DOI: 10.3390/ijms23105641] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/30/2022] [Revised: 05/09/2022] [Accepted: 05/13/2022] [Indexed: 02/04/2023] Open
Abstract
Bartter (BS) and Gitelman (GS) syndrome are autosomal recessive inherited tubulopathies, whose clinical diagnosis can be challenging, due to rarity and phenotypic overlap. Genotype-phenotype correlations have important implications in defining kidney and global outcomes. The aim of our study was to assess the diagnostic rate of whole-exome sequencing (WES) coupled with a bioinformatic analysis of copy number variations in a population of 63 patients with BS and GS from a single institution, and to explore genotype-phenotype correlations. We obtained a diagnostic yield of 86% (54/63 patients), allowing disease reclassification in about 14% of patients. Although some clinical and laboratory features were more commonly reported in patients with BS or GS, a significant overlap does exist, and age at onset, preterm birth, gestational age and nephro-calcinosis are frequently misleading. Finally, chronic kidney disease (CKD) occurs in about 30% of patients with BS or GS, suggesting that the long-term prognosis can be unfavorable. In our cohort the features associated with CKD were lower gestational age at birth and a molecular diagnosis of BS, especially BS type 1. The results of our study demonstrate that WES is useful in dealing with the phenotypic heterogeneity of these disorders, improving differential diagnosis and genotype-phenotype correlation.
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Wu CY, Tsai MH, Chen CC, Kao CH. Early diagnosis of Gitelman syndrome in a young child: A case report. World J Clin Cases 2022; 10:2844-2850. [PMID: 35434103 PMCID: PMC8968817 DOI: 10.12998/wjcc.v10.i9.2844] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/23/2021] [Revised: 12/11/2021] [Accepted: 02/20/2022] [Indexed: 02/06/2023] Open
Abstract
BACKGROUND Gitelman syndrome (GS) is an autosomal recessive renal tubular disorder characterized by renal wasting hypokalemia, metabolic alkalosis, hypomagnesemia, and hypocalciuria. It is usually caused by mutations in the gene SLC12A3, which encodes the thiazide-sensitive Na-Cl cotransporter. GS is not usually diagnosed until late childhood or adulthood.
CASE SUMMARY Here, we report the case of a one-year-old girl who was brought to the emergency department due to persistent vomiting for two days. On admission to our hospital, generalized weakness was observed, and laboratory investigations revealed severe hypokalemia (1.9 mmol/L). However, persistent hypokalemia was observed during outpatient follow-up. Suspicion of the GS phenotype was assessed via the patient’s clinical presentation, family history, and biochemical analysis of blood and urine. Further genetic analysis was performed for her and her family by exon-wide sequencing analysis of the gene SLC12A3. The genetic diagnosis of GS was established in the Taiwanese family with three affected individuals, two of whom were children (7 years/17 years) without obvious symptoms, with the youngest being only one year old (patient in our case).
CONCLUSION We successfully demonstrated the early diagnosis of GS using family genetic analysis. Any instances of hypokalemia should not be neglected, as early detection of GS with suitable treatment can prevent patients from potentially life-threatening complications.
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Affiliation(s)
- Chun-Yen Wu
- Department of Pediatrics, Far Eastern Memorial Hospital, New Taipei City 220, Taiwan
| | - Ming-Hsein Tsai
- Department of Internal Medicine, Shin-Kong Wu Ho-Su Memorial Hospital, Taipei 111, Taiwan
| | - Chia-Chun Chen
- Department of Pediatrics, Far Eastern Memorial Hospital, New Taipei City 220, Taiwan
| | - Chuan-Hong Kao
- Department of Pediatrics, Far Eastern Memorial Hospital, New Taipei City 220, Taiwan
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El-Asmar N, Rajpal A, Arafah BM. Primary Hyperaldosteronism: Approach to Diagnosis and Management. Med Clin North Am 2021; 105:1065-1080. [PMID: 34688415 DOI: 10.1016/j.mcna.2021.06.007] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Hyperaldosteronism is a relatively more common disorder than previously recognized. Patients with hyperaldosteronism are at high risk for cardiovascular events. Patients suspected of having hyperaldosteronism should undergo initial screening and subsequent confirmatory testing to establish a biochemical diagnosis. Although adrenal computed tomography/magnetic resonance imaging scans often define a disease's subtype, adrenal vein sampling, in order to determine lateralization, may be necessary in some patients who are surgical candidates. Medical therapy using optimal doses of mineralocorticoid receptor antagonists can control symptoms and normalize plasma renin activity. The long-term outcome of patients treated with either surgical or optimal medical therapy appears similar.
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Affiliation(s)
- Nadine El-Asmar
- Division of Clinical and Molecular Endocrinology, University Hospitals Cleveland Medical Center, 11100 Euclid Avenue, Cleveland, OH 44106, USA; Case Western Reserve University, Cleveland, OH, USA
| | - Aman Rajpal
- Case Western Reserve University, Cleveland, OH, USA; Louis Stokes VA Medical Center, 10701 East Blvd, Cleveland OH 44106, USA
| | - Baha M Arafah
- Division of Clinical and Molecular Endocrinology, University Hospitals Cleveland Medical Center, 11100 Euclid Avenue, Cleveland, OH 44106, USA; Case Western Reserve University, Cleveland, OH, USA.
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Nuñez-Gonzalez L, Carrera N, Garcia-Gonzalez MA. Molecular Basis, Diagnostic Challenges and Therapeutic Approaches of Bartter and Gitelman Syndromes: A Primer for Clinicians. Int J Mol Sci 2021; 22:11414. [PMID: 34768847 PMCID: PMC8584233 DOI: 10.3390/ijms222111414] [Citation(s) in RCA: 18] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/15/2021] [Revised: 10/13/2021] [Accepted: 10/14/2021] [Indexed: 12/18/2022] Open
Abstract
Gitelman and Bartter syndromes are rare inherited diseases that belong to the category of renal tubulopathies. The genes associated with these pathologies encode electrolyte transport proteins located in the nephron, particularly in the Distal Convoluted Tubule and Ascending Loop of Henle. Therefore, both syndromes are characterized by alterations in the secretion and reabsorption processes that occur in these regions. Patients suffer from deficiencies in the concentration of electrolytes in the blood and urine, which leads to different systemic consequences related to these salt-wasting processes. The main clinical features of both syndromes are hypokalemia, hypochloremia, metabolic alkalosis, hyperreninemia and hyperaldosteronism. Despite having a different molecular etiology, Gitelman and Bartter syndromes share a relevant number of clinical symptoms, and they have similar therapeutic approaches. The main basis of their treatment consists of electrolytes supplements accompanied by dietary changes. Specifically for Bartter syndrome, the use of non-steroidal anti-inflammatory drugs is also strongly supported. This review aims to address the latest diagnostic challenges and therapeutic approaches, as well as relevant recent research on the biology of the proteins involved in disease. Finally, we highlight several objectives to continue advancing in the characterization of both etiologies.
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Affiliation(s)
- Laura Nuñez-Gonzalez
- Grupo de Xenetica e Bioloxia do Desenvolvemento das Enfermidades Renais, Laboratorio de Nefroloxia (No. 11), Instituto de Investigacion Sanitaria de Santiago (IDIS), Complexo Hospitalario de Santiago de Compostela (CHUS), 15706 Santiago de Compostela, Spain;
- Grupo de Medicina Xenomica, Complexo Hospitalario de Santiago de Compostela (CHUS), 15706 Santiago de Compostela, Spain
| | - Noa Carrera
- Grupo de Xenetica e Bioloxia do Desenvolvemento das Enfermidades Renais, Laboratorio de Nefroloxia (No. 11), Instituto de Investigacion Sanitaria de Santiago (IDIS), Complexo Hospitalario de Santiago de Compostela (CHUS), 15706 Santiago de Compostela, Spain;
- Grupo de Medicina Xenomica, Complexo Hospitalario de Santiago de Compostela (CHUS), 15706 Santiago de Compostela, Spain
- RedInRen (Red en Investigación Renal) RETIC (Redes Temáticas de Investigación Cooperativa en Salud), ISCIII (Instituto de Salud Carlos III), 28029 Madrid, Spain
| | - Miguel A. Garcia-Gonzalez
- Grupo de Xenetica e Bioloxia do Desenvolvemento das Enfermidades Renais, Laboratorio de Nefroloxia (No. 11), Instituto de Investigacion Sanitaria de Santiago (IDIS), Complexo Hospitalario de Santiago de Compostela (CHUS), 15706 Santiago de Compostela, Spain;
- Grupo de Medicina Xenomica, Complexo Hospitalario de Santiago de Compostela (CHUS), 15706 Santiago de Compostela, Spain
- RedInRen (Red en Investigación Renal) RETIC (Redes Temáticas de Investigación Cooperativa en Salud), ISCIII (Instituto de Salud Carlos III), 28029 Madrid, Spain
- Fundación Pública Galega de Medicina Xenomica—SERGAS, Complexo Hospitalario de Santiago de Compotela (CHUS), 15706 Santiago de Compostela, Spain
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Takemori S, Tanigaki S, Nozu K, Yoshihashi H, Uchiumi Y, Sakaguchi K, Tsushima K, Kitamura A, Kobayashi C, Matsuhima M, Tajima A, Nagano C, Kobayashi Y. Prenatal diagnosis of MAGED2 gene mutation causing transient antenatal Bartter syndrome. Eur J Med Genet 2021; 64:104308. [PMID: 34400373 DOI: 10.1016/j.ejmg.2021.104308] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/14/2021] [Revised: 07/31/2021] [Accepted: 08/12/2021] [Indexed: 12/01/2022]
Abstract
Transient antenatal Bartter syndrome due to melanoma-associated antigen D2 gene mutation is a newly reported type of Bartter syndrome. Its characteristics include an X-linked inheritance pattern, early-onset hydramnios, and spontaneous disappearance of symptoms after childbirth. To date, there have been no reports of prenatally diagnosed cases. We herein present the case of a preterm male born to a mother with early-onset hydramnios and a family history of X-linked idiopathic hydramnios. We suspected melanoma-associated antigen D2 gene mutation and performed direct sequencing. As a result, we were able to prenatally establish a diagnosis of transient Bartter syndrome due to a melanoma-associated antigen D2 gene mutation.
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Affiliation(s)
- Satoshi Takemori
- Department of Obstetrics and Gynecology, Kyorin University Hospital, Tokyo, Japan.
| | - Shinji Tanigaki
- Department of Obstetrics and Gynecology, Kyorin University Hospital, Tokyo, Japan
| | - Kandai Nozu
- Department of Pediatrics, Kobe University Graduate School of Medicine, Kobe, Hyogo, Japan
| | - Hiroshi Yoshihashi
- Department of Medical Genetics, Tokyo Metropolitan Children's Medical Center, Tokyo, Japan
| | - Yutaro Uchiumi
- Department of Obstetrics and Gynecology, Kyorin University Hospital, Tokyo, Japan
| | - Kyoko Sakaguchi
- Department of Obstetrics and Gynecology, Kyorin University Hospital, Tokyo, Japan
| | - Kana Tsushima
- Department of Obstetrics and Gynecology, Kyorin University Hospital, Tokyo, Japan
| | - Aya Kitamura
- Department of Obstetrics and Gynecology, Kyorin University Hospital, Tokyo, Japan
| | - Chie Kobayashi
- Department of Obstetrics and Gynecology, Kyorin University Hospital, Tokyo, Japan
| | - Miho Matsuhima
- Department of Obstetrics and Gynecology, Kyorin University Hospital, Tokyo, Japan
| | - Atsushi Tajima
- Department of Obstetrics and Gynecology, Kyorin University Hospital, Tokyo, Japan
| | - China Nagano
- Department of Pediatrics, Kobe University Graduate School of Medicine, Kobe, Hyogo, Japan
| | - Yoichi Kobayashi
- Department of Obstetrics and Gynecology, Kyorin University Hospital, Tokyo, Japan
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A Rare Cause of Refractory Severe Polyhydramnios: Antenatal Bartter Syndrome. ACTA ACUST UNITED AC 2021; 57:medicina57030272. [PMID: 33809664 PMCID: PMC8002264 DOI: 10.3390/medicina57030272] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/01/2021] [Revised: 03/13/2021] [Accepted: 03/15/2021] [Indexed: 11/17/2022]
Abstract
Background: Antenatal Bartter syndrome is an autosomal recessive disorder causing severe polyuria that leads to severe polyhydramnios and preterm labor. Prenatal diagnosis of antenatal Bartter syndrome is difficult because the genetic diagnosis can only be confirmed following a clinical diagnosis in infants. Reports of prenatal diagnosis and treatment of antenatal Bartter syndrome are limited. Case Presentation: We present the case of a 33-year-old pregnant woman with refractory polyhydramnios at 31 weeks of gestation. There were no structural anomalies or placental problems on ultrasonography; therefore, antenatal Bartter syndrome was suspected. With repeated amniocentesis and indomethacin therapy, the pregnancy continued to 36 weeks of gestation. The clinical features of the infant and subsequent genetic testing confirmed the diagnosis of antenatal Bartter syndrome. The baby was in good clinical condition at the 3-month follow-up visit. Conclusions: For pregnant women with early onset and refractory severe polyhydramnios without morphological anomalies, antenatal Bartter syndrome should be highly suspected.
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Hanna RM, Ahdoot RS, Kalantar-Zadeh K, Ghobry L, Kurtz I. Calcium Transport in the Kidney and Disease Processes. Front Endocrinol (Lausanne) 2021; 12:762130. [PMID: 35299844 PMCID: PMC8922474 DOI: 10.3389/fendo.2021.762130] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/21/2021] [Accepted: 11/25/2021] [Indexed: 11/25/2022] Open
Abstract
Calcium is a key ion involved in cardiac and skeletal muscle contractility, nerve function, and skeletal structure. Global calcium balance is affected by parathyroid hormone and vitamin D, and calcium is shuttled between the extracellular space and the bone matrix compartment dynamically. The kidney plays an important role in whole-body calcium balance. Abnormalities in the kidney transport proteins alter the renal excretion of calcium. Various hormonal and regulatory pathways have evolved that regulate the renal handling of calcium to maintain the serum calcium within defined limits despite dynamic changes in dietary calcium intake. Dysregulation of renal calcium transport can occur pharmacologically, hormonally, and via genetic mutations in key proteins in various nephron segments resulting in several disease processes. This review focuses on the regulation transport of calcium in the nephron. Genetic diseases affecting the renal handling of calcium that can potentially lead to changes in the serum calcium concentration are reviewed.
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Affiliation(s)
- Ramy M. Hanna
- Division of Nephrology, Department of Medicine, University of California Irvine (UCI) School of Medicine, Orange, CA, United States
- *Correspondence: Ramy M. Hanna,
| | - Rebecca S. Ahdoot
- Division of Nephrology, Department of Medicine, University of California Irvine (UCI) School of Medicine, Orange, CA, United States
| | - Kamyar Kalantar-Zadeh
- Division of Nephrology, Department of Medicine, University of California Irvine (UCI) School of Medicine, Orange, CA, United States
| | - Lena Ghobry
- School of Public Health, University of Pittsburgh, Pittsburgh, PA, United States
| | - Ira Kurtz
- Division of Nephrology, Department of Medicine, David Geffen School of Medicine, University of California Los Angeles (UCLA), Los Angeles, CA, United States
- University of California Los Angeles (UCLA) Brain Research Center, Los Angeles, CA, United States
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Thyroid Function in 35 Patients with Gitelman Syndrome. BIOMED RESEARCH INTERNATIONAL 2020. [DOI: 10.1155/2020/7963898] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
Abstract
Objective. In this study, we aimed to analyze thyroid function and related risk factors for thyroid dysfunction in 35 patients with Gitelman syndrome (GS). Methods. This study included 35 patients with GS who were referred to West China Hospital of Sichuan University from Aug 2013 to Jan 2018. General patient characteristics were collected, and thyroid function was assessed. To evaluate the potential contribution of hypokalemia to thyroid dysfunction, 636 patients who were clinically diagnosed with primary aldosteronism (PA) during the same period were included as the control group; these patients were divided into a hypokalemia group (
) and a normokalemia group (
). Logistic regression was used to screen for significant determinants of thyroid dysfunction in the GS patients. Results. Patients with GS had a significantly different prevalence of subclinical hypothyroidism, hypothyroidism, and hyperthyroidism than patients with hypokalemic PA and normokalemic PA (28.6%, 2.9%, and 11.4% vs. 15.5%, 6.1%, and 0.7% vs. 8.3%, 4.6%, and 2.8%,
). No significant difference was observed in the distribution of thyroid function between the hypokalemic PA group and the normokalemic PA group (
). No significant differences were seen in the positive rates of thyrotropin receptor antibody (TRAb), thyroglobulin antibody (TGAb), and thyroid peroxidase antibody (TPOAb) among the three groups (
). In the logistic regression, only sex (OR, 7.4; 95% CI, 1.555-35.479;
) was significantly correlated with thyroid dysfunction in GS patients. Conclusion. GS is complicated with a greater rate of thyroid dysfunction than primary aldosteronism. The risk of thyroid dysfunction in female patients with GS is higher than that in male patients.
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Yu RZ, Chen MS. Gitelman syndrome caused by a rare homozygous mutation in the SLC12A3 gene: A case report. World J Clin Cases 2020; 8:4252-4258. [PMID: 33024786 PMCID: PMC7520782 DOI: 10.12998/wjcc.v8.i18.4252] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/25/2020] [Revised: 07/18/2020] [Accepted: 08/13/2020] [Indexed: 02/05/2023] Open
Abstract
BACKGROUND Gitelman syndrome (GS) is an unusual, autosomal recessive salt-losing tubulopathy characterized by hypokalemic metabolic alkalosis, hypomagnesemia and hypocalciuria. It is caused by mutations in the solute carrier family 12 member 3 (SLC12A3) gene resulting in disordered function of the thiazide-sensitive NaCl co-transporter. To date, many types of mutations in the SLC12A3 gene have been discovered that trigger different clinical manifestations. Therefore, gene sequencing should be considered before determining the course of treatment for GS patients.
CASE SUMMARY A 55-year-old man was admitted to our department due to hand numbness and fatigue. Laboratory tests after admission showed hypokalemia, metabolic alkalosis and renal failure, all of which suggested a diagnosis of GS. Genome sequencing of DNA extracted from the patient’s peripheral blood showed a rare homozygous mutation in the SLC12A3 gene (NM_000339.2: chr16:56903671, Exon4, c.536T>A, p.Val179Asp). This study reports a rare homozygous mutation in SLC12A3 gene of a Chinese patient with GS.
CONCLUSION Genetic studies may improve the diagnostic accuracy of Gitelman syndrome and improve genetic counseling for individuals and their families with these types of genetic disorders
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Affiliation(s)
- Ri-Zhen Yu
- Department of Nephrology Division, Zhejiang Provincial People’s Hospital, People’s Hospital of Hangzhou Medical College, Hangzhou 310014, Zhejiang Province, China
| | - Mao-Sheng Chen
- Department of Nephrology Division, Zhejiang Provincial People’s Hospital, People’s Hospital of Hangzhou Medical College, Hangzhou 310014, Zhejiang Province, China
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Bartter Syndrome Masquerading as Acute Kidney Injury in a Neonate. Indian Pediatr 2020. [PMID: 32999122 PMCID: PMC7498554 DOI: 10.1007/s13312-020-1973-9] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
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Wu X, Yang G, Chen S, Tang M, Jian S, Chen F, Wu X. Bartter syndrome with long-term follow-up: a case report. J Int Med Res 2020; 48:300060520947876. [PMID: 32857947 PMCID: PMC7705384 DOI: 10.1177/0300060520947876] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022] Open
Abstract
Bartter syndrome is a rare inherited disease caused by CLCNKB mutation, which results in inactivation of the chloride channel Kb protein. Bartter syndrome is characterized by extreme hypokalemia, hypochloremia, metabolic alkalosis, hyperrenin-induced angiotensinemia, hyperaldosteronemia, and normal blood pressure. We herein report a case of Bartter syndrome that manifested as vomiting, hypokalemia, metabolic alkalosis, normal blood pressure, and significant hyperrenin-induced angiotensinemia. The patient, a 5-month-old girl, carried two known heterozygous pathogenic mutations: c.88C > T (p.Arg30*), which she had inherited from her father, and c.1313G > A (p.Arg438His), which she had inherited from her mother. Treatment with indomethacin, a nonsteroidal anti-inflammatory drug, led to rapid improvement of the hypokalemia, and treatment was continued for 14 years. The indomethacin also induced a sustainable reduction in the hypokalemia and metabolic alkalosis.
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Affiliation(s)
- Xueling Wu
- Department of Respiratory Medicine, Renji Hospital, School of Medicine, Shanghai Jiaotong University, Shanghai, China
| | - Gang Yang
- Department of Cardiology, the Second Affiliated Hospital of Chongqing Medical University, Chongqing, Sichuan, China
| | - Shiyu Chen
- Key Laboratory of Diagnostic Medicine designated by the Chinese Ministry of Education, Chongqing Medical University, Chongqing, Sichuan, China
| | - Min Tang
- Key Laboratory of Diagnostic Medicine designated by the Chinese Ministry of Education, Chongqing Medical University, Chongqing, Sichuan, China
| | - Shan Jian
- Department of Paediatrics, Peking Union Medical College Hospital, Beijing, China
| | - Fuhui Chen
- Department of Respiratory, the Second Affiliated Hospital of Harbin Medical University, Harbin, Heilongjiang, China
| | - Xiulin Wu
- Department of Geriatrics, Southwest Hospital, Military Medical University, Chongqing, China
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Chinen T, Saeki E, Mori T, Sohara E, Uchida S, Akimoto T. A case of Gitelman syndrome: our experience with a patient treated in clinical practice on a local island. J Rural Med 2019; 14:258-262. [PMID: 31788154 PMCID: PMC6877917 DOI: 10.2185/jrm.3014] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/07/2019] [Accepted: 05/31/2019] [Indexed: 12/28/2022] Open
Abstract
Background: Gitelman syndrome (GS) is an autosomal recessive salt-losing
renal tubulopathy resulting from mutations in the thiazide-sensitive Na-Cl cotransporter
(NCC) gene. Notably, lack of awareness regarding GS and difficulty with
prompt diagnosis are observed in clinical practice, particularly in rural settings. Case presentation: We report a case of a 48-year-old man with GS who
presented to a local clinic on a remote island. Occasional laboratory investigations
incidentally revealed a reduced serum potassium level of 2.6 mmol/L. A careful medical
interview revealed episodes of intermittent paralysis of the lower extremities and
muscular weakness for >30 years. Subsequent laboratory investigations revealed
hypomagnesemia, hypocalciuria, and hypokalemic metabolic alkalosis. Based on the patient’s
history, clinical presentation, and laboratory investigations, we suspected GS. Genetic
testing revealed a rare homozygous in-frame 18 base insertion in the NCC
gene that might have resulted from the founder effect, consequent to his topographically
isolated circumstances. Conclusion: More case studies similar to our study need to be added to the
literature to gain a deeper understanding of the functional consequences of this mutation
and to establish optimal management strategies for this condition, particularly in rural
clinical settings.
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Affiliation(s)
- Takashi Chinen
- Department of Clinical Oncology, Jichi Medical University, Japan.,Setouchi-Cho Hekichi Clinic, Japan
| | - Eiji Saeki
- Division of Nephrology, Department of Internal Medicine, Amami Central Hospital, Japan
| | - Takayasu Mori
- Department of Nephrology, Tokyo Medical and Dental University, Japan
| | - Eisei Sohara
- Department of Nephrology, Tokyo Medical and Dental University, Japan
| | - Shinichi Uchida
- Department of Nephrology, Tokyo Medical and Dental University, Japan
| | - Tetsu Akimoto
- Division of Nephrology, Department of Internal Medicine, Jichi Medical University, Japan
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Li J, Hu S, Nie Y, Wang R, Tan M, Li H, Zhu S. A novel compound heterozygous KCNJ1 gene mutation presenting as late-onset Bartter syndrome: Case report. Medicine (Baltimore) 2019; 98:e16738. [PMID: 31441846 PMCID: PMC6716717 DOI: 10.1097/md.0000000000016738] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/27/2022] Open
Abstract
RATIONALE Bartter syndrome is an autosomal-recessive inherited disease in which patients present with hypokalemia and metabolic alkalosis. We present 1 case with Bartter syndrome, due to a novel compound heterozygous mutation in the KCNJ1 gene encoding the ATP-sensitive inward rectifier potassium channel in the thick ascending limb of the loop of Henle. PATIENT CONCERNS A patient was admitted to our hospital because of weakness, polyuria, and polydipsia. At presentation to our hospital, the female Chinese patient was 34 years old and her physical examination was normal. Laboratory studies revealed hypokalemia, metabolic alkalosis, hypercalciuria, hyperparathyroidemia, and hyper-reninemia. In addition, urinary potassium was obviously higher. Computer tomography scan confirmed the patient had the bilateral medullary nephrocalcinosis. DIAGNOSIS Blood samples were received from the patient and her parents, and deoxyribonucleic acid was extracted. The genetic analysis of SLC12A1, SLC12A3, KCNJ1, CLCNKB, BSND, and CASR was performed. The compound heterozygous KCNJ1 gene mutation was validated using conventional Sanger sequencing methods. INTERVENTIONS The patient was treated with potassium supplementation. Her blood and urine chemistries improved over the next week. Serum potassium normalized with improvement in polyuria and polydipsia over the next month. OUTCOMES Our patient was compound heterozygous for Thr234Ile and Thr71Met in the KCNJ1 gene. The c.701C>T variant predicted a change from a threonine codon to an isoleucine codon (p.Thr234Ile). The c.212C>T variant predicted a change from a threonine codon to a methionine codon (p.Thr71Met). The unaffected mother was heterozygous for the Thr234Ile mutation, whereas unaffected father was heterozygous for the Thr71Met mutation. LESSONS The phenotypes of the patient were similar to other patients with Bartter syndrome. The phenotypes of the patient could eventually be explained by the presence of the novel compound heterozygous p.Thr234Ile/p.Thr71Met variants in the KCNJ1 gene.
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Affiliation(s)
- Jingyi Li
- Department of Endocrinology, The First Affiliated Hospital, Tsinghua University
| | - Shoulong Hu
- Department of Ophthalmology, Beijing Children's Hospital, Capital Medical University
| | - Yi Nie
- Department of Endocrinology, The First Affiliated Hospital, Tsinghua University
| | - Rongfeng Wang
- Department of Radiology, The First Affiliated Hospital, Tsinghua University, Beijing, P.R. China
| | - Ming Tan
- Department of Endocrinology, The First Affiliated Hospital, Tsinghua University
| | - Hongmei Li
- Department of Endocrinology, The First Affiliated Hospital, Tsinghua University
| | - Shuanli Zhu
- Department of Endocrinology, The First Affiliated Hospital, Tsinghua University
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Najafi M, Kordi-Tamandani DM, Behjati F, Sadeghi-Bojd S, Bakey Z, Karimiani EG, Schüle I, Azarfar A, Schmidts M. Mimicry and well known genetic friends: molecular diagnosis in an Iranian cohort of suspected Bartter syndrome and proposition of an algorithm for clinical differential diagnosis. Orphanet J Rare Dis 2019; 14:41. [PMID: 30760291 PMCID: PMC6375149 DOI: 10.1186/s13023-018-0981-5] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/23/2018] [Accepted: 12/14/2018] [Indexed: 12/21/2022] Open
Abstract
BACKGROUND Bartter Syndrome is a rare, genetically heterogeneous, mainly autosomal recessively inherited condition characterized by hypochloremic hypokalemic metabolic alkalosis. Mutations in several genes encoding for ion channels localizing to the renal tubules including SLC12A1, KCNJ1, BSND, CLCNKA, CLCNKB, MAGED2 and CASR have been identified as underlying molecular cause. No genetically defined cases have been described in the Iranian population to date. Like for other rare genetic disorders, implementation of Next Generation Sequencing (NGS) technologies has greatly facilitated genetic diagnostics and counseling over the last years. In this study, we describe the clinical, biochemical and genetic characteristics of patients from 15 Iranian families with a clinical diagnosis of Bartter Syndrome. RESULTS Age range of patients included in this study was 3 months to 6 years and all patients showed hypokalemic metabolic alkalosis. 3 patients additionally displayed hypercalciuria, with evidence of nephrocalcinosis in one case. Screening by Whole Exome Sequencing (WES) and long range PCR revealed that 12/17 patients (70%) had a deletion of the entire CLCNKB gene that was previously identified as the most common cause of Bartter Syndrome in other populations. 4/17 individuals (approximately 25% of cases) were found to suffer in fact from pseudo-Bartter syndrome resulting from congenital chloride diarrhea due to a novel homozygous mutation in the SLC26A3 gene, Pendred syndrome due to a known homozygous mutation in SLC26A4, Cystic Fibrosis (CF) due to a novel mutation in CFTR and apparent mineralocorticoid excess syndrome due to a novel homozygous loss of function mutation in HSD11B2 gene. 1 case (5%) remained unsolved. CONCLUSIONS Our findings demonstrate deletion of CLCNKB is the most common cause of Bartter syndrome in Iranian patients and we show that age of onset of clinical symptoms as well as clinical features amongst those patients are variable. Further, using WES we were able to prove that nearly 1/4 patients in fact suffered from Pseudo-Bartter Syndrome, reversing the initial clinical diagnosis with important impact on the subsequent treatment and clinical follow up pathway. Finally, we propose an algorithm for clinical differential diagnosis of Bartter Syndrome.
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Affiliation(s)
- Maryam Najafi
- Genome Research Division, Human Genetics department, Radboud University Medical Center, Geert Grooteplein Zuid 10, 6525KL, Nijmegen, The Netherlands.,Departement of Biology, University of Sistan and Baluchestan, Zahedan, Iran
| | | | - Farkhondeh Behjati
- Genetics Research Center, University of Social Welfare and Rehabilitation Sciences, Tehran, Iran
| | - Simin Sadeghi-Bojd
- Children and Adolescents Health Research Center, resistant tuberculosis institute, Zahedan University of Medical Sciences, Zahedan, Iran
| | - Zeineb Bakey
- Genome Research Division, Human Genetics department, Radboud University Medical Center, Geert Grooteplein Zuid 10, 6525KL, Nijmegen, The Netherlands.,Center for Pediatrics and Adolescent Medicine, Freiburg University Hospital, Freiburg University Faculty of Medicine, Mathildenstrasse 1, 79112, Freiburg, Germany
| | - Ehsan Ghayoor Karimiani
- Razavi Cancer Research, Razavi Hospital, Imam Reza International University, Mashhad, Iran.,Next Generation Genetic Polyclinic, Mashhad, Iran
| | - Isabel Schüle
- Center for Pediatrics and Adolescent Medicine, Freiburg University Hospital, Freiburg University Faculty of Medicine, Mathildenstrasse 1, 79112, Freiburg, Germany
| | - Anoush Azarfar
- Department of Pediatrics, Faculty of Medicine, Mashhad University of Medical Sciences, Mashhad, Iran
| | - Miriam Schmidts
- Genome Research Division, Human Genetics department, Radboud University Medical Center, Geert Grooteplein Zuid 10, 6525KL, Nijmegen, The Netherlands. .,Center for Pediatrics and Adolescent Medicine, Freiburg University Hospital, Freiburg University Faculty of Medicine, Mathildenstrasse 1, 79112, Freiburg, Germany. .,Center for Pediatrics and Adolescent Medicine, University Hospital Freiburg, 79112, Freiburg, Germany.
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18
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Gitelman Syndrome: A Rare Cause of Seizure Disorder and a Systematic Review. Case Rep Med 2019; 2019:4204907. [PMID: 30867665 PMCID: PMC6379858 DOI: 10.1155/2019/4204907] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/26/2018] [Revised: 11/20/2018] [Accepted: 01/17/2019] [Indexed: 01/06/2023] Open
Abstract
Gitelman syndrome is one of the few inherited causes of metabolic alkalosis due to salt losing tubulopathy. It is caused by tubular defects at the level of distal convoluted tubules, mimicking a thiazide-like tumor. It usually presents in late childhood or in teenage as nonspecific weakness, fatigability, polyuria, and polydipsia but very rarely with seizures. It is classically associated with hypokalemia, hypomagnesemia, hypocalciuria, hyperreninemia, and hyperaldosteronism. However, less frequently, it can present with normal magnesium levels. It is even rarer to find normomagnesemic patients of GS who develop seizures as the main complication since hypomagnesemia is considered the principal etiology of abnormal foci of seizure-related brain activity in GS cases. Interestingly, patients with GS are oftentimes diagnosed during pregnancy when the classic electrolyte pattern consistent with GS is noticed. Our case presents GS with normal serum magnesium in a patient, with seizures being the main clinical presentation. We also did a comprehensive literature review of 122 reported cases to show the prevalence of normal magnesium in GS cases and an overview of clinical and biochemical variability in GS. We suggest that further studies and in-depth analysis are required to understand the pathophysiology of seizures in GS patients with both normal and low magnesium levels.
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Abstract
Bartter syndrome is an inherited renal tubular disorder caused by a defective salt reabsorption in the thick ascending limb of loop of Henle, resulting in salt wasting, hypokalemia, and metabolic alkalosis. Mutations of several genes encoding the transporters and channels involved in salt reabsorption in the thick ascending limb cause different types of Bartter syndrome. A poor phenotype-genotype relationship due to the interaction with other cotransporters and different degrees of compensation through alternative pathways is currently reported. However, phenotypic identification still remains the first step to guide the suspicion of Bartter syndrome. Given the rarity of the syndrome, and the lack of genetic characterization in most cases, limited clinical evidence for treatment is available and the therapy is based mainly on the comprehension of renal physiology and relies on the physician's personal experiences. A better understanding of the mutated channels and transporters could possibly generate targets for specific treatment in the future, also encompassing drugs aiming to correct deficiencies in folding or plasma membrane expression of the mutated proteins.
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Affiliation(s)
- Tamara da Silva Cunha
- Nephrology Division, Universidade Federal de São Paulo (UNIFESP), Escola Paulista de Medicina, São Paulo, Brazil,
| | - Ita Pfeferman Heilberg
- Nephrology Division, Universidade Federal de São Paulo (UNIFESP), Escola Paulista de Medicina, São Paulo, Brazil,
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Fujimura J, Nozu K, Yamamura T, Minamikawa S, Nakanishi K, Horinouchi T, Nagano C, Sakakibara N, Nakanishi K, Shima Y, Miyako K, Nozu Y, Morisada N, Nagase H, Ninchoji T, Kaito H, Iijima K. Clinical and Genetic Characteristics in Patients With Gitelman Syndrome. Kidney Int Rep 2018; 4:119-125. [PMID: 30596175 PMCID: PMC6308995 DOI: 10.1016/j.ekir.2018.09.015] [Citation(s) in RCA: 35] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/22/2018] [Revised: 09/07/2018] [Accepted: 09/20/2018] [Indexed: 12/13/2022] Open
Abstract
Introduction Gitelman syndrome (GS) is a tubulopathy exhibited by salt loss. GS cases are most often diagnosed by chance blood test. Aside from that, some cases are also diagnosed from tetanic symptoms associated with hypokalemia and/or hypomagnesemia or short stature. As for complications, thyroid dysfunction and short stature are known, but the incidence rates for these complications have not yet been elucidated. In addition, no genotype–phenotype correlation has been identified in GS. Methods We examined the clinical characteristics and genotype–phenotype correlation in genetically proven GS cases with homozygous or compound heterozygous variants in SLC12A3 (n = 185). Results In our cohort, diagnostic opportunities were by chance blood tests (54.7%), tetany (32.6%), or short stature (7.2%). Regarding complications, 16.3% had short stature, 13.7% had experienced febrile convulsion, 4.3% had thyroid dysfunction, and 2.5% were diagnosed with epilepsy. In one case, QT prolongation was detected. Among 29 cases with short stature, 10 were diagnosed with growth hormone (GH) deficiency and GH replacement therapy started. Interestingly, there was a strong correlation in serum magnesium levels between cases with p.Arg642Cys and/or p.Leu858His and cases without these variants, which are mutational hotspots in the Japanese population (1.76 mg/dl vs. 1.43 mg/dl, P < 0.001). Conclusion This study has revealed, for the first time, clinical characteristics in genetically proven GS cases in the Japanese population, including prevalence of complications. Patients with hypokalemia detected by chance blood test should have gene tests performed. Patients with GS need attention for developing extrarenal complications, such as short stature, febrile convulsion, thyroid dysfunction, epilepsy, or QT prolongation. It was also revealed for the first time that hypomagnesemia was not severe in some variants in SLC12A3.
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Affiliation(s)
- Junya Fujimura
- Department of Pediatrics, Kobe University Graduate School of Medicine, Kobe, Japan
| | - Kandai Nozu
- Department of Pediatrics, Kobe University Graduate School of Medicine, Kobe, Japan
- Correspondence: Kandai Nozu, Department of Pediatrics, Kobe University Graduate School of Medicine, 7-5-1 Kusunoki-cho, Chuo, Kobe, Hyogo 6500017, Japan.
| | - Tomohiko Yamamura
- Department of Pediatrics, Kobe University Graduate School of Medicine, Kobe, Japan
| | - Shogo Minamikawa
- Department of Pediatrics, Kobe University Graduate School of Medicine, Kobe, Japan
| | - Keita Nakanishi
- Department of Pediatrics, Kobe University Graduate School of Medicine, Kobe, Japan
| | - Tomoko Horinouchi
- Department of Pediatrics, Kobe University Graduate School of Medicine, Kobe, Japan
| | - China Nagano
- Department of Pediatrics, Kobe University Graduate School of Medicine, Kobe, Japan
| | - Nana Sakakibara
- Department of Pediatrics, Kobe University Graduate School of Medicine, Kobe, Japan
| | - Koichi Nakanishi
- Department of Child Health and Welfare (Pediatrics), Graduate School of Medicine, University of the Ryukyus, Nishihara, Japan
| | - Yuko Shima
- Department of Pediatrics, Wakayama Medical University, Wakayama, Japan
| | - Kenichi Miyako
- Department of Pediatrics, Beppu Medical Center, Oita, Japan
| | - Yoshimi Nozu
- Department of Pediatrics, Kobe University Graduate School of Medicine, Kobe, Japan
| | - Naoya Morisada
- Department of Pediatrics, Kobe University Graduate School of Medicine, Kobe, Japan
| | - Hiroaki Nagase
- Department of Pediatrics, Kobe University Graduate School of Medicine, Kobe, Japan
| | - Takeshi Ninchoji
- Department of Pediatrics, Kobe University Graduate School of Medicine, Kobe, Japan
| | - Hiroshi Kaito
- Department of Pediatrics, Kobe University Graduate School of Medicine, Kobe, Japan
| | - Kazumoto Iijima
- Department of Pediatrics, Kobe University Graduate School of Medicine, Kobe, Japan
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21
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Profound Hypokalaemia Resulting in Maternal Cardiac Arrest: A Catastrophic Complication of Hyperemesis Gravidarum? Case Rep Obstet Gynecol 2018; 2018:4687587. [PMID: 30151287 PMCID: PMC6087565 DOI: 10.1155/2018/4687587] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/01/2018] [Accepted: 07/08/2018] [Indexed: 11/18/2022] Open
Abstract
We present a case of a 39-year-old G8P6 Pacific Islander woman who at 15+5 weeks' gestation had an out-of-hospital cardiac arrest secondary to profound hypokalaemia which was associated with severe hyperemesis gravidarum (HG). Her clinical course after arrest was complicated by a second 5-minute cardiac arrest in the Intensive Care Unit (ICU) (pre-arrest potassium 1.8), anuric renal failure requiring dialysis, ischaemic hepatitis, and encephalopathy and unfortunately fetal demise and a spontaneous miscarriage on day 2 of admission. Despite these complications, she was discharged home 4 weeks later with a full recovery. Following a plethora of inpatient and outpatient investigations, the cause of her cardiac arrest was determined to be profound hypokalaemia. The hypokalaemia was presumed second to a perfect storm of HG with subsequent nutritional deficiencies causing electrolyte wasting, extracellular fluid (ECF) volume reduction, and activation of the renin-angiotensin-aldosterone axis (RAAS). This combined with the physiological changes that promote potassium wasting in pregnancy including volume expansion, increased renal blood flow, increased glomerular filtration rate, and increase in cortisol contributed to the patient having a profoundly low total body potassium level. This diagnosis is further strengthened by the fact that her pre- and post-pregnancy potassium levels were within normal limits in the absence of supplementary potassium. This case highlights the potentially life-threatening electrolyte imbalances that can occur with HG and the importance of recognising the disease, comprehensive electrolyte monitoring, and aggressive management in pregnancy.
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Meyer M, Berrios M, Lo C. Transient Antenatal Bartter's Syndrome: A Case Report. Front Pediatr 2018; 6:51. [PMID: 29594084 PMCID: PMC5857533 DOI: 10.3389/fped.2018.00051] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/14/2017] [Accepted: 02/23/2018] [Indexed: 12/01/2022] Open
Abstract
Antenatal Bartter's syndrome is a rare inherited disorder characterized by fetal polyhydramnios and polyuria that is usually detected between 24 and 30 weeks of gestation. However, a rare, severe, but transient form of antenatal Bartter's syndrome due to an x-linked melanoma-associated antigen D2 (MAGED2) mutation has recently been described. This transient type results in the earlier onset of severe polyhydramnios and preterm birth, but spontaneously resolves postnatally. Here, we present a case of a 29-week gestation male born to a mother with severe polyhydramnios, who was subsequently found to have a novel mutation for MAGED2 not previously reported. This is the first and only case not to be treated with indomethacin, yet still resulted in spontaneous resolution of symptoms. Our case suggests the need for awareness of and testing for this new mutation in cases of severe antenatal polyhydramnios and discusses the perinatal treatment of this condition.
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Affiliation(s)
- Michelle Meyer
- UCSF Benioff Children's Hospital Oakland, Oakland, CA, United States
| | - Margarita Berrios
- UCSF Benioff Children's Hospital Oakland, Oakland, CA, United States
| | - Christina Lo
- UCSF Benioff Children's Hospital Oakland, Oakland, CA, United States
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23
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Zanoli L, Lentini P, Fatuzzo P. Digoxin and Hypermagnesuria. Nephron Clin Pract 2017; 138:89-91. [DOI: 10.1159/000484574] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/21/2017] [Accepted: 10/24/2017] [Indexed: 12/23/2022] Open
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Breinbjerg A, Siggaard Rittig C, Gregersen N, Rittig S, Hvarregaard Christensen J. A novel variant in the SLC12A1 gene in two families with antenatal Bartter syndrome. Acta Paediatr 2017; 106:161-167. [PMID: 27748541 DOI: 10.1111/apa.13635] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/11/2016] [Revised: 09/20/2016] [Accepted: 10/13/2016] [Indexed: 12/27/2022]
Abstract
AIM Bartter syndrome is an autosomal-recessive inherited disease in which patients present with hypokalaemia and metabolic alkalosis. We present two apparently nonrelated cases with antenatal Bartter syndrome type I, due to a novel variant in the SLC12A1 gene encoding the bumetanide-sensitive sodium-(potassium)-chloride cotransporter 2 in the thick ascending limb of the loop of Henle. METHODS Blood samples were received from the two cases and 19 of their relatives, and deoxyribonucleic acid was extracted. The coding regions of the SLC12A1 gene were amplified using polymerase chain reaction, followed by bidirectional direct deoxyribonucleic acid sequencing. RESULTS Each affected child in the two families was homozygous for a novel inherited variant in the SLC12A1gene, c.1614T>A. The variant predicts a change from a tyrosine codon to a stop codon (p.Tyr538Ter). The two cases presented antenatally and at six months of age, respectively. CONCLUSION The two cases were homozygous for the same variant in the SLC12A1 gene, but presented clinically at different ages. This could eventually be explained by the presence of other gene variants or environmental factors modifying the phenotypes. The phenotypes of the patients were similar to other patients with antenatal Bartter syndrome.
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Affiliation(s)
- Anders Breinbjerg
- Department of Pediatrics; Aarhus University Hospital; Aarhus Denmark
| | | | - Niels Gregersen
- Research Unit for Molecular Medicine; Aarhus University Hospital; Aarhus Denmark
| | - Søren Rittig
- Department of Pediatrics; Aarhus University Hospital; Aarhus Denmark
| | - Jane Hvarregaard Christensen
- Department of Pediatrics; Aarhus University Hospital; Aarhus Denmark
- Department of Biomedicine; Aarhus University; Aarhus Denmark
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Lopez HU, Haverfield E, Chung WK. Whole-Exome Sequencing Reveals CLCNKB Mutations in a Case of Sudden Unexpected Infant Death. Pediatr Dev Pathol 2015; 18:324-6. [PMID: 25923035 DOI: 10.2350/14-08-1543-cr.1] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
Cases of sudden unexpected infant death (SUID) leave many families devastated, especially in those without an identified cause of death. Here, we describe the case of an apparently healthy 15-day-old infant who died suddenly and unexpectedly. Through whole-exome sequencing, the infant was posthumously found to have 2 mutations in the CLCNKB gene, leading to a molecular diagnosis of Bartter syndrome type III, the likely cause of death. This case illustrates the potential utility of exome sequencing in cases of SUID to suggest a diagnosis, with important implications for families, allowing them to come to closure over the cause of death, informing their future reproductive decisions, and minimizing the risk of recurrence.
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Affiliation(s)
- Hector U Lopez
- 1 Columbia University College of Physicians & Surgeons, 630 West 168th Street, New York, NY 10032, USA
| | | | - Wendy K Chung
- 3 Department of Pediatrics and Medicine, Columbia University Medical Center, 1150 St Nicholas Avenue, Room 620, New York, NY 10032, USA
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Koulouridis E, Koulouridis I. Molecular pathophysiology of Bartter's and Gitelman's syndromes. World J Pediatr 2015; 11:113-25. [PMID: 25754753 DOI: 10.1007/s12519-015-0016-4] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/09/2014] [Accepted: 10/23/2014] [Indexed: 12/17/2022]
Abstract
BACKGROUND In the last two decades, progress in cytogenetic and genome research has enabled investigators to unravel the underlying molecular mechanisms of inherited tubulopathies such as Bartter's and Gitelman's syndromes and helped physicians to better understand not only these two pathologic entities but also renal pathophysiology and salt sensitive hypertension. DATA SOURCES Articles collected from PubMed and open access journals included original articles, research articles, and comprehensive reviews. They were evaluated by the authors with an special emphasis on originality and up to date information about molecular pathophysiology. RESULTS Bartter's and Gitelman's syndromes are two different inherited salt loosing tubulopathies. They are characterized by various inability of distal nephron to reabsorb sodium chloride with resultant extarcellular volume contraction and increased activity of the renin angiotensin aldosterone system. Hypokalemic metabolic alkalosis is a common feature of these two forms of tubulopathies. Hypercalciuria characterizes the majority of Bartter's syndrome, and hypomagnesemia with hypocalciuria characterizes Gitelman's syndrome. Low blood pressure is a common feature among patients who suffered from these tubulopathies. Bartter's syndromes encompass a heterogeneous group of ion channels defects localized at the thick ascending limp of Henle's loop with resultant loss of function of sodium-potassium-2 chloride cotransporter. These defects result in the impairment of the countercurrent multiplication system of the kidney as well as calcium, potassium and acid base disturbances which in the majority of cases are proved lethal especially in the antenatal and/or immediate postnatal life period. The underlying pathology in Gitelman's syndrome is defined to the distal convoluted tubule and is related to loss of function of the sodium-chloride cotransporter. The results of this defect encompass the inability of extracellular volume homeostasis, magnesium and potassium conservation, and acid base disturbances which are generally mild and in the majority of cases are not life-threatening. CONCLUSIONS Recent advances in molecular pathophysiology of Bartter's and Gitelman's syndromes have helped physicians to better understand the underlying mechanisms of these pathologic entities which remain obscure. Data collected from experiments among genetically manipulated animals enable us to better understand the pathophysiology of mammalian kidney and the underlying mechanisms of salt sensitive hypertension and to lay a foundation for the future development of new drugs, especially diuretics and antihypertensive drugs.
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Shinar S, Gal-Oz A, Weinstein T, Levin I, Maslovitz S. Gitelman syndrome during pregnancy – from diagnosis to treatment: a case series and review of the literature. CASE REPORTS IN PERINATAL MEDICINE 2014. [DOI: 10.1515/crpm-2013-0043] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
Abstract
Abstract
Objective: Gitelman syndrome (GS) is a rare renal disease, originating from a defect in the Na-Cl co-transporter in the distal tubule, which causes hypokalemia, hypomagnesemia, hypocalciuria, metabolic alkalosis and low-normal blood pressure. Mild hypokalemia of pregnancy is physiological. Fatigue, nausea, vomiting, polyuria and low blood pressures are also common complaints associated with a normal pregnancy. Therefore, the diagnosis of an organic renal disorder, i.e., GS, may go undetected, until severe hypokalemia and possible life-threatening cardiac arrhythmias develop. Maternal consequences are obvious. The possibility of fetal pathology remains unclear.
Study design: In this study, we describe nine pregnancies in seven women with a clinical diagnosis of GS. Nearly all women were diagnosed initially during pregnancy. We describe their clinical presentation, serum and urine electrolyte levels during pregnancy and immediately post-partum, their treatment and pregnancy outcome.
Results: Fetal pregnancy outcomes were mostly favorable. While it is likely that women suffering from GS do not require special fetal surveillance, they are at high risk for electrolyte depletion and thus aggravation of GS during pregnancy.
Conclusion: Clinical suspicion of GS should arise in all women presenting with symptomatic hypokalemia. Once the diagnosis is made, adequate supplementation and routine maternal monitoring should ensue.
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Affiliation(s)
| | - Amir Gal-Oz
- Department of Nephrology, Tel-Aviv Sourasky Medical Center, Sackler Faculty of Medicine, Tel-Aviv University, Tel Aviv, Israel
| | - Talia Weinstein
- Department of Nephrology, Tel-Aviv Sourasky Medical Center, Sackler Faculty of Medicine, Tel-Aviv University, Tel Aviv, Israel
| | - Ishai Levin
- Department of Gynecology, Lis Maternity Hospital, Tel-Aviv Sourasky Medical Center, Sackler Faculty of Medicine, Tel-Aviv University, Tel Aviv, Israel
| | - Sharon Maslovitz
- Department of Gynecology, Lis Maternity Hospital, Tel-Aviv Sourasky Medical Center, Sackler Faculty of Medicine, Tel-Aviv University, Tel Aviv, Israel
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Penquerc’h M, Picot D, Vigneau C. Le magnésium : un super cation méconnu ? Revue générale et enquête auprès des généralistes d’Ille-et-Vilaine. Nephrol Ther 2014; 10:25-34. [DOI: 10.1016/j.nephro.2013.09.004] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/11/2013] [Revised: 08/22/2013] [Accepted: 09/10/2013] [Indexed: 10/25/2022]
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Demssie YN, Patel L, Kumar M, Syed AA. Hypomagnesaemia: clinical relevance and management. Br J Hosp Med (Lond) 2014; 75:39-43. [DOI: 10.12968/hmed.2014.75.1.39] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Affiliation(s)
- Yared N Demssie
- Consultant Physician, Royal Blackburn Hospital, Blackburn BB2 3HH
| | - Leena Patel
- Foundation Year 2 Trainee, Royal Blackburn Hospital, Blackburn BB2 3HH
| | - Mohit Kumar
- Specialist Trainee in the Department of Endocrinology, Royal Blackburn Hospital, Blackburn BB2 3HH
| | - Akheel A Syed
- Consultant Physician in the Department of Endocrinology, Salford Royal NHS Foundation Trust, Salford and The University of Manchester, Manchester
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Ueda K, Makita N, Kawarazaki H, Fujiwara T, Unuma S, Monkawa T, Hayashi M, Fujita T. A novel compound heterozygous mutation of Gitelman's syndrome in Japan, as diagnosed by an extraordinary response of the fractional excretion rate of chloride in the trichlormethiazide loading test. Intern Med 2012; 51:1549-53. [PMID: 22728489 DOI: 10.2169/internalmedicine.51.6727] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
Gitelman's syndrome (GS), an inherited disorder due to loss of function of ion channels and transporters such as Na-Cl co-transporter (NCCT) in distal convoluted tubules, is characterized by hypokalemia, hypomagnesemia, hypocalciuria, metabolic alkalosis and hyperreninemic-hyperaldosteronism. A 39-year-old man was admitted to our hospital because of muscle weakness with such intractable disorders. We performed a thiazide-loading test, which revealed a poor response of the fractional excretion rate of chloride compared to healthy subjects. Based on these data, the clinical diagnosis of GS was made. Gene-sequencing analysis revealed compound heterozygous mutations of c.539C > A and c.1844C > T in SLC12A3, which is newly reported in Japanese GS.
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Affiliation(s)
- Kohei Ueda
- Department of Nephrology and Endocrinology, University of Tokyo School of Medicine, Japan.
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Impaired phosphorylation of Na(+)-K(+)-2Cl(-) cotransporter by oxidative stress-responsive kinase-1 deficiency manifests hypotension and Bartter-like syndrome. Proc Natl Acad Sci U S A 2011; 108:17538-43. [PMID: 21972418 DOI: 10.1073/pnas.1107452108] [Citation(s) in RCA: 110] [Impact Index Per Article: 8.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/30/2022] Open
Abstract
Na(+)-K(+)-2Cl(-) cotransporters (NKCCs), including NKCC1 and renal-specific NKCC2, and the Na(+)-Cl(-) cotransporter (NCC) play pivotal roles in the regulation of blood pressure (BP) and renal NaCl reabsorption. Oxidative stress-responsive kinase-1 (OSR1) is a known upstream regulator of N(K)CCs. We generated and analyzed global and kidney tubule-specific (KSP) OSR1 KO mice to elucidate the physiological role of OSR1 in vivo, particularly on BP and kidney function. Although global OSR1(-/-) mice were embryonically lethal, OSR1(+/-) mice had low BP associated with reduced phosphorylated (p) STE20 (sterile 20)/SPS1-related proline/alanine-rich kinase (SPAK) and p-NKCC1 abundance in aortic tissue and attenuated p-NKCC2 abundance with increased total and p-NCC expression in the kidney. KSP-OSR1(-/-) mice had normal BP and hypercalciuria and maintained significant hypokalemia on a low-K(+) diet. KSP-OSR1(-/-) mice exhibited impaired Na(+) reabsorption in the thick ascending loop on a low-Na(+) diet accompanied by remarkably decreased expression of p-NKCC2 and a blunted response to furosemide, an NKCC2 inhibitor. The expression of total SPAK and p-SPAK was significantly increased in parallel to that of total NCC and p-NCC despite unchanged total NKCC2 expression. These results suggest that, globally, OSR1 is involved in the regulation of BP and renal tubular Na(+) reabsorption mainly via the activation of NKCC1 and NKCC2. In the kidneys, NKCC2 but not NCC is the main target of OSR1 and the reduced p-NKCC2 in KSP-OSR1(-/-) mice may lead to a Bartter-like syndrome.
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Seyberth HW, Schlingmann KP. Bartter- and Gitelman-like syndromes: salt-losing tubulopathies with loop or DCT defects. Pediatr Nephrol 2011; 26:1789-802. [PMID: 21503667 PMCID: PMC3163795 DOI: 10.1007/s00467-011-1871-4] [Citation(s) in RCA: 111] [Impact Index Per Article: 8.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/29/2010] [Revised: 03/09/2011] [Accepted: 03/09/2011] [Indexed: 12/11/2022]
Abstract
Salt-losing tubulopathies with secondary hyperaldosteronism (SLT) comprise a set of well-defined inherited tubular disorders. Two segments along the distal nephron are primarily involved in the pathogenesis of SLTs: the thick ascending limb of Henle's loop, and the distal convoluted tubule (DCT). The functions of these pre- and postmacula densa segments are quite distinct, and this has a major impact on the clinical presentation of loop and DCT disorders - the Bartter- and Gitelman-like syndromes. Defects in the water-impermeable thick ascending limb, with its greater salt reabsorption capacity, lead to major salt and water losses similar to the effect of loop diuretics. In contrast, defects in the DCT, with its minor capacity of salt reabsorption and its crucial role in fine-tuning of urinary calcium and magnesium excretion, provoke more chronic solute imbalances similar to the effects of chronic treatment with thiazides. The most severe disorder is a combination of a loop and DCT disorder similar to the enhanced diuretic effect of a co-medication of loop diuretics with thiazides. Besides salt and water supplementation, prostaglandin E2-synthase inhibition is the most effective therapeutic option in polyuric loop disorders (e.g., pure furosemide and mixed furosemide-amiloride type), especially in preterm infants with severe volume depletion. In DCT disorders (e.g., pure thiazide and mixed thiazide-furosemide type), renin-angiotensin-aldosterone system (RAAS) blockers might be indicated after salt, potassium, and magnesium supplementation are deemed insufficient. It appears that in most patients with SLT, a combination of solute supplementation with some drug treatment (e.g., indomethacin) is needed for a lifetime.
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Affiliation(s)
- Hannsjörg W. Seyberth
- Department of Pediatrics and Adolescent Medicine, Philipps University, Marburg, Germany ,Lazarettgarten 23, 76829 Landau, Germany
| | - Karl P. Schlingmann
- Department of General Pediatrics, University Children’s Hospital, Münster, Germany
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Bartter syndrome in two sisters with a novel mutation of the CLCNKB gene, one with deafness. Eur J Pediatr 2011; 170:1209-11. [PMID: 21479528 DOI: 10.1007/s00431-011-1464-z] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/20/2011] [Accepted: 03/22/2011] [Indexed: 12/15/2022]
Abstract
This article describes two sisters with type III Bartter syndrome (BS) due to a novel missense variant of the CLCNKB gene. The phenotypic expression of the disease was very different in these two siblings. In one sister, the disease followed a very severe course, especially in the neonatal period and as a toddler. Both the classic symptoms and the biochemical features of the syndrome were striking. In addition, she presented with sensorineural deafness, a complication yet unreported in this subtype of BS In contrast, the least affected sister was symptom free and the biochemical features of the disease although present remained discrete throughout the prolonged follow-up. It is suggested that such a difference in the phenotypic expression of the disease is possibly secondary to the modifier effect of a gene and/or results from environmental factor(s).
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Sampathkumar K, Muralidharan U, Kannan A, Ramakrishnan M, Ajeshkumar R. Childhood Bartter's syndrome: An Indian case series. Indian J Nephrol 2011; 20:207-10. [PMID: 21206684 PMCID: PMC3008951 DOI: 10.4103/0971-4065.73455] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/15/2023] Open
Abstract
This is a retrospective analysis of children diagnosed with Bartter's syndrome (BS) between 2001 and 2009 in our hospital. Seven children (six males) were diagnosed with BS. The mean age at presentation was 6.5 ± 4.9 months. The presenting features were failure to thrive,vomiting, polyuria, and dehydration. All children were normotensive at admission. The children exhibited alkalemia (pH, 7.58 ± 0.03), hypokalemia (serum potassium, 2.62 ± 0.47 mEq/l), hypochloremia (serum chloride, 82.83 ± 16.7 mEq/l), and hyponatremia (serum sodium, 126.85 ± 3.56 mEq/l). Disproportionate urinary wasting of sodium, potassium, and chloride were seen. The diagnosis was confirmed by elevated serum levels of both renin and aldosterone with normotension. Indomethacin or ibuprofen therapy resulted in marked improvement in general condition of these children. In conclusion, a high index of suspicion should be entertained in children with failure to thrive to diagnose BS. Therapy with NSAIDs leads to marked improvement in the general well being.
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Affiliation(s)
- K Sampathkumar
- Department of Nephrology, Meenakshi Mission Hospital and Research Centre, Madurai - 625 107, India
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Hinschberger O, Martzolff L, Ioannou G, Baumann D, Jaeger F, Kieffer P. [Acquired Gitelman syndrome associated with Sjögren's syndrome and scleroderma]. Rev Med Interne 2010; 32:e96-8. [PMID: 20888090 DOI: 10.1016/j.revmed.2010.08.017] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/15/2009] [Revised: 08/20/2010] [Accepted: 08/20/2010] [Indexed: 12/01/2022]
Abstract
Tubulopathy can complicate autoimmune diseases. It is usually a distal tubular acidosis, but Fanconi syndrome or Bartter syndrome has been exceptionally reported. We report a case of acquired Gitelman syndrome in a 32-year-old male who also presented diffuse scleroderma autoimmune thyroiditis, and Sjögren's syndrome. Only three cases of Sjögren syndrome associated with Gitelman syndrome have been previously reported in literature. The absence of other cases in the family and absence of mutation SLC12A3 emphasise the relation between autoimmune disease and this tubulopathy.
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Affiliation(s)
- O Hinschberger
- Service de médecine interne et soins continus, centre hospitalier de Mulhouse, 20, rue du Docteur-Laennec, 68134 Mulhouse cedex, France
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Herrero-Morín JD, Rodríguez J, Coto E, Gil-Peña H, Alvarez V, Espinosa L, Loris C, Gil-Calvo M, Santos F. Gitelman syndrome in Gypsy paediatric patients carrying the same intron 9 + 1 G>T mutation. Clinical features and impact on quality of life. Nephrol Dial Transplant 2010; 26:151-5. [PMID: 20571093 DOI: 10.1093/ndt/gfq352] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
BACKGROUND Gitelman syndrome is a primary tubular disorder causing hypokalaemic metabolic alkalosis with hypocalciuria. Its prevalence is high in Gypsies, who harbour an identical mutation, intron 9 + 1 G>T, in the SLC12A3 gene. METHODS To better define the Gitelman syndrome in Gypsies, the clinical and biochemical features of 34 Spanish paediatric Gypsy patients were analysed. At diagnosis, symptoms, height and weight as well as serum and urinary biochemical data were collected. During a follow-up of 4.5 ± 2.4 years [X ± standard deviation (SD)], therapy, treatment compliance, symptoms, frequency of hospital admissions and, at the last visit, growth and biochemical work-up of 29 patients followed for at least 6 months were analysed. Quality of life items were also assessed by a questionnaire. RESULTS Muscle cramps (41%) and asthenia (35%) were the most frequent presenting symptoms. Biochemical data at diagnosis were serum K 2.76 ± 0.46 mEq/L, serum Mg 1.32 ± 0.28 mg/dL, blood pH 7.45 ± 0.06, serum bicarbonate 28.2 ± 2.9 mEq/L, urinary calcium/creatinine ratio 0.03 ± 0.04 mg/mg, fractional K excretion 24.4 ± 17.1% and fractional Mg excretion 8.9 ± 8.3%. During follow-up, Mg and K supplements were prescribed to 79 and 86% of patients, respectively; compliance with treatment was good in 35%. Hospital admission rate was 0.03/patient/month. Muscle cramps were the symptom most often referred by the patients (45%) during the follow-up, and 71% of patients considered their health status as excellent or good. Twenty-one patients stated that their disease did not adversely interfere with their mood or social relationships. Height and weight of patients at diagnosis were -0.60 ± 1.17 and -0.49 ± 1.32 SD, respectively, and improved to -0.44 ± 1.28 (P < 0.05) and 0.18 ± 1.79 SD (P < 0.01) at the last visit. CONCLUSIONS Gypsy children with Gitelman syndrome mostly exhibit muscle symptoms and asthenia although the disease is not particularly severe in this ethnic group. Body growth improves with treatment and close follow-up.
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Menegon LF, Amaral TN, Gontijo JAR. Renal Sodium Handling Study in an Atypical Case of Bartter's Syndrome Associated with Mitochondriopathy and Sensorineural Blindness. Ren Fail 2009; 26:195-7. [PMID: 15287206 DOI: 10.1081/jdi-120038522] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/03/2022] Open
Abstract
Bartter's syndrome is a disorder that has been linked to mutations in one of three ion transporter proteins: NKCC2 (type I), ROMK (type II) and CCLNKB (type III), which affects a final common pathway that participates in ion transport by thick ascending limb cells. We present an atypical case of mitochondriopathy combined with tubule functional disturbances compatible with Bartter's syndrome and definitive sensorineural blindness. Our patient had a peculiar clinical presentation with signs of salt and volume depletion, low blood pressure and secondary hyperaldosteronism, associated with hypokalemic metabolic alkalosis, hypocalcemia and severe hypomagnesemia, uncommon in genetic forms of Bartter's syndrome. The enhanced absolute and fractional sodium excretion in our patient compared to volunteers was accompanied by increased post-proximal sodium rejection, suggesting a striking ion transport dysfunction in these nephron segments. These findings lead to the Bartter's syndrome diagnosis, accompanied by a suppose mitochondrial tick ascending loop of Henle epithelium dysfunction that may reflect the high energy supplied by mitochondria electron transport chain, required for this nephron segment to maintain normal ion transport.
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Affiliation(s)
- L F Menegon
- Disciplina de Medicina Interna, Laboratório Balanço Hidro-Salino, Núcleo de Medicina e Cirurgia Experimental, Departamento de Clínica Médica, Faculdade de Ciências Médicas, Universidade Estadual de Campinas, Campinas, Sao Paulo, Brazil
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de Arriba G, Sánchez-Heras M, Basterrechea MA. Gitelman syndrome during pregnancy: a therapeutic challenge. Arch Gynecol Obstet 2009; 280:807-9. [DOI: 10.1007/s00404-009-0994-3] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/22/2008] [Accepted: 02/05/2009] [Indexed: 10/21/2022]
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Seyberth HW. An improved terminology and classification of Bartter-like syndromes. ACTA ACUST UNITED AC 2008; 4:560-7. [PMID: 18695706 DOI: 10.1038/ncpneph0912] [Citation(s) in RCA: 92] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/20/2008] [Accepted: 07/04/2008] [Indexed: 12/15/2022]
Abstract
This Review outlines a terminology and classification of Bartter-like syndromes that is based on the underlying causes of these inherited salt-losing tubulopathies and is, therefore, more clinically relevant than the classical definition. Three major types of salt-losing tubulopathy can be defined: distal convoluted tubule dysfunction leading to hypokalemia (currently known as Gitelman or Bartter syndrome), the more-severe condition of polyuric loop dysfunction (often referred to as antenatal Bartter or hyperprostaglandin E syndrome), and the most-severe condition of combined loop and distal convoluted tubule dysfunction (antenatal Bartter or hyperprostaglandin E syndrome with sensorineural deafness). These three subtypes can each be further subdivided according to the identity of the defective ion transporter or channel: the sodium-chloride cotransporter NCCT or the chloride channel ClC-Kb in distal convoluted tubule dysfunction; the sodium-potassium-chloride cotransporter NKCC2 or the renal outer medullary potassium channel in loop dysfunction; and the chloride channels ClC-Ka and ClC-Kb or their beta-subunit Barttin in combined distal convoluted tubule and loop dysfunction. This new classification should help clinicians to better understand the pathophysiology of these syndromes and choose the most appropriate treatment for affected patients, while avoiding potentially harmful diagnostic and therapeutic approaches.
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Affiliation(s)
- Hannsjörg W Seyberth
- Center for Pediatric and Adolescent Medicine, Philipps University, Marburg, Germany.
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Gitelman syndrome in pregnancy. Int J Gynaecol Obstet 2008; 103:69-71. [DOI: 10.1016/j.ijgo.2008.05.007] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/28/2008] [Revised: 05/12/2008] [Accepted: 05/12/2008] [Indexed: 11/23/2022]
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Martin KJ, González EA, Slatopolsky E. Clinical consequences and management of hypomagnesemia. J Am Soc Nephrol 2008; 20:2291-5. [PMID: 18235082 DOI: 10.1681/asn.2007111194] [Citation(s) in RCA: 97] [Impact Index Per Article: 6.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022] Open
Abstract
Magnesium deficiency and hypomagnesemia remain quite prevalent, particularly in patients in intensive care units, and may have important clinical consequences. Magnesium should be measured directly in clinical circumstances in which a risk for magnesium deficiency exists and appropriately corrected when found. This commentary reviews the current knowledge of magnesium homeostasis and the risk factors and clinical consequences of magnesium deficiency and outlines approaches to therapy.
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Affiliation(s)
- Kevin J Martin
- Division of Nephrology, Saint Louis University, St. Louis, Missouri, USA
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Riveira-Munoz E, Chang Q, Godefroid N, Hoenderop JG, Bindels RJ, Dahan K, Devuyst O. Transcriptional and functional analyses of SLC12A3 mutations: new clues for the pathogenesis of Gitelman syndrome. J Am Soc Nephrol 2007; 18:1271-83. [PMID: 17329572 DOI: 10.1681/asn.2006101095] [Citation(s) in RCA: 107] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022] Open
Abstract
Gitelman syndrome (GS) is a recessive salt-losing tubulopathy that is caused by mutations in the SLC12A3 gene that encodes the sodium-chloride co-transporter (NCC). GS is characterized by significant inter- and intrafamilial phenotype variability, with early onset and/or severe clinical manifestations in some patients. No correlations between the disease variability and the position/nature of SLC12A3 mutations have been investigated thus far. In this study, extensive mutational analyses of SLC12A3 were performed in 27 patients with GS, including genomic DNA sequencing, multiplex ligation-dependent probe amplification, cDNA analysis, and quantification of allele-specific transcripts, in parallel with functional analyses in Xenopus laevis oocytes and detailed phenotyping. Twenty-six SLC12A3 mutations were identified in 25 patients with GS, including eight novel (detection rate 80%). Transcript analysis demonstrated that splicing mutations of SLC12A3 lead to frameshifted mRNA subject to degradation by nonsense-mediated decay. Heterologous expression documented a novel class of NCC mutants with defective intrinsic transport activity. A subgroup of patients presented with early onset, growth retardation, and/or detrimental manifestations, confirming the potential severity of GS. The mutations that were associated with a severe presentation were the combination at least for one allele of a missplicing resulting in a truncated transcript that was downregulated by nonsense-mediated decay or a nonfunctional, cell surface-absent mutant. The most recurrent mutation on the second allele was a newly described NCC mutant that affected the functional properties of the co-transporter. These data suggest that the nature/position of SLC12A3 mutation, combined with male gender, is a determinant factor in the severity of GS and provide new insights in the underlying pathogenic mechanisms of the disease.
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Affiliation(s)
- Eva Riveira-Munoz
- Division of Nephrology, Université Catholique de Louvain Medical School, Brussels, Belgium
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Hashida T, Yamada M, Hashimoto K, Satoh T, Okada S, Shibusawa N, Ishizuka T, Mori M. Loss of consciousness and hypokalemia in an elderly man with a mutation of the thiazide-sensitive Na-Cl cotransporter gene. Endocr J 2006; 53:859-63. [PMID: 16966826 DOI: 10.1507/endocrj.k06-076] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/23/2022] Open
Abstract
An 80-year-old man was referred to our department for evaluation of repetitive loss of consciousness and faintness with hypokalemia. He had relatively low blood pressure, hypomagnesemia, hypocalciuria and chondrocalcinosis in the knee, clinically suggesting Gitelman's syndrome. A renal clearance study could not be carried out due to the patient's age and complications of the heart. Sequence analysis of the gene of thiazide-sensitive Na-Cl cotransporter (TSC) showed a heterozygous missense mutation from C to T at 1712 base pairs from the translation start site, with resultant changes in codon 569 from alanine to valine (A569V). Treatment with oral administration of potassium chloride improved all the symptoms. Although Gitelman's syndrome has been considered to be autosomal recessive, cases of only heterozygous mutation detected have recently been reported. Therefore, the mutation found in this patient may be responsible for Gitelman's syndrome.
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Affiliation(s)
- Tetsu Hashida
- Department of Medicine and Molecular Science, Gunma University Graduate School of Medicine, Maebashi, Japan
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Naesens M, Steels P, Verberckmoes R, Vanrenterghem Y, Kuypers D. Bartter's and Gitelman's syndromes: from gene to clinic. Nephron Clin Pract 2004; 96:p65-78. [PMID: 15056980 DOI: 10.1159/000076752] [Citation(s) in RCA: 104] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022] Open
Abstract
Bartter's and Gitelman's syndromes are characterized by hypokalemia, normal to low blood pressure and hypochloremic metabolic alkalosis. Recently, investigators have been able to demonstrate mutations of six genes encoding several renal tubular transporters and ion channels that can be held responsible for Bartter's and Gitelman's syndromes. Neonatal Bartter's syndrome is caused by mutations of NKCC2 or ROMK, classic Bartter's syndrome by mutations of ClC-Kb, Bartter's syndrome associated with sensorineural deafness is due to mutations of BSND, Gitelman's syndrome to mutations of NCCT and Bartter's syndrome associated with autosomal dominant hypocalcemia is linked to mutations of CASR. We review the pathophysiology of these syndromes in relation to their clinical presentation.
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Affiliation(s)
- Maarten Naesens
- Department of Nephrology, Katholieke Universiteit Leuven, Belgium
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Sabath E, Meade P, Berkman J, de los Heros P, Moreno E, Bobadilla NA, Vázquez N, Ellison DH, Gamba G. Pathophysiology of functional mutations of the thiazide-sensitive Na-Cl cotransporter in Gitelman disease. Am J Physiol Renal Physiol 2004; 287:F195-203. [PMID: 15068971 DOI: 10.1152/ajprenal.00044.2004] [Citation(s) in RCA: 71] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022] Open
Abstract
Most of the missense mutations that have been described in the human SLC12A3 gene encoding the thiazide-sensitive Na(+)-Cl(-) cotransporter (TSC, NCC, or NCCT), as the cause of Gitelman disease, block TSC function by interfering with normal protein processing and glycosylation. However, some mutations exhibit considerable activity. To investigate the pathogenesis of Gitelman disease mediated by such mutations and to gain insights into structure-function relationships on the cotransporter, five functional disease mutations were introduced into mouse TSC cDNA, and their expression was determined in Xenopus laevis oocytes. Western blot analysis revealed immunoreactive bands in all mutant TSCs that were undistinguishable from wild-type TSC. The activity profile was: wild-type TSC (100%) > G627V (66%) > R935Q (36%) = V995M (32%) > G610S (12%) > A585V (6%). Ion transport kinetics in all mutant clones were similar to wild-type TSC, except in G627V, in which a small but significant increase in affinity for extracellular Cl(-) was observed. In addition, G627V and G610S exhibited a small increase in metolazone affinity. The surface expression of wild-type and mutant TSCs was performed by laser-scanning confocal microscopy. All mutants exhibited a significant reduction in surface expression compared with wild-type TSC, with a profile similar to that observed in functional expression analysis. Our data show that biochemical and functional properties of the mutant TSCs are similar to wild-type TSC but that the surface expression is reduced, suggesting that these mutations impair the insertion of a functional protein into the plasma membrane. The small increase in Cl(-) and thiazide affinity in G610S and G627V suggests that the beginning of the COOH-terminal domain could be implicated in defining kinetic properties.
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Affiliation(s)
- Ernesto Sabath
- Molecular Physiology Unit, Instituto Nacional de Ciencias Médicas y Nutrición Salvador Zubirán, Instituto de Investigaciones Biomédicas, Universidad Nacional Autónoma de México, Tlalpan 14000, Mexico City, Mexico
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Lin SH, Cheng NL, Hsu YJ, Halperin ML. Intrafamilial phenotype variability in patients with Gitelman syndrome having the same mutations in their thiazide-sensitive sodium/chloride cotransporter. Am J Kidney Dis 2004; 43:304-12. [PMID: 14750096 DOI: 10.1053/j.ajkd.2003.10.018] [Citation(s) in RCA: 71] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/14/2023]
Abstract
BACKGROUND Gitelman syndrome (GS) most often results from mutations in the thiazide-sensitive sodium chloride cotransporter (NCC). Although the severity of symptoms may vary in patients who have the same mutations, a markedly different clinical presentation in family members with identical mutations is truly rare. METHODS Five patients (3 women and 2 men) belonging to 2 unrelated Chinese families were investigated. All had chronic hypokalemia, renal potassium (K+) wasting, metabolic alkalosis, and normal blood pressure. Direct sequencing of both the NCC and CLCNKB genes were performed. RESULTS The probands in each family were men. They had very severe hypokalemia and were symptomatic with episodes of paralysis. They had normal plasma magnesium concentrations, normal calcium excretion rates, and impaired maximal urine concentrating ability. In contrast, female family members were asymptomatic. They had laboratory findings typical of GS--less severe hypokalemia, hypomagnesemia, hypocalciuria, and intact maximal renal concentrating ability. Nevertheless, all patients had the same novel pair of NCC mutations and no mutations detected in CLCNKB. CONCLUSION Differences in sex may help explain the different clinical presentations in these 2 Chinese families with novel NCC mutations. Hypomagnesemia and hypocalciuria are not always present in patients with GS.
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Affiliation(s)
- Shih-Hua Lin
- Division of Nephrology, Department of Medicine, Tri-Service General Hospital, National Defense Medical Center, Taipei, Taiwan.
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Chen YC, Yang WC, Yang AH, Lin SH, Li HY, Lin CC. Primary Sjögren's syndrome associated with Gitelman's syndrome presenting with muscular paralysis. Am J Kidney Dis 2003; 42:586-90. [PMID: 12955689 DOI: 10.1016/s0272-6386(03)00792-3] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
Abstract
A 38-year-old woman presented with muscle cramping of 4 extremities and paralysis for months. Laboratory results showed an elevated antinuclear antibody titer; antibodies to the ribonucleoprotein antigen Ro; hypokalemia; hypomagnesemia with hyperreninemia, but abnormally high urine potassium and magnesium levels and low urine calcium levels; and a blunted diuretic effect to thiazide, but not furosemide, which met the criteria for Gitelman's syndrome (GS) and led to the diagnosis of primary Sjögren's syndrome (pSS). She received medical treatment, including a potassium supplement and aldosterone antagonist. GS as a presentation of pSS has never been reported in the literature. The features of renal diseases related to SS are reviewed. SS is the underlying cause of GS, which may precede the onset of the well-known sicca complex.
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Affiliation(s)
- Yen-Cheng Chen
- Department of Medicine, Division of Nephrology, Taipei Veterans General Hospital, Taipei, Taiwan
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Sardani Y, Qin K, Haas M, Aronson AJ, Rosenfield RL. Bartter syndrome complicated by immune complex nephropathy. Case report and literature review. Pediatr Nephrol 2003; 18:913-8. [PMID: 12836094 DOI: 10.1007/s00467-003-1194-1] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/31/2002] [Revised: 04/07/2003] [Accepted: 04/07/2003] [Indexed: 12/22/2022]
Abstract
The unusual coincidence of Bartter syndrome and C1q nephropathy is described and the literature reviewed. An African-American girl presented at 4 years of age with acute hyponatremic dehydration and failure to thrive. Persistent hypokalemic alkalosis and secondary hyperaldosteronism were found. The case was atypical for Bartter syndrome in that proteinuria (0.19 g/day) was present. Renal biopsy showed juxtaglomerular hyperplasia and C1q nephropathy. Molecular analysis showed deletion of the renal chloride channel gene (CLCNKB) typical of autosomal recessive childhood Bartter syndrome. Chronic sodium and potassium chloride replacement therapy together with indomethacin normalized her metabolic status, and she experienced catch-up growth. Proteinuria persisted, however. This is the first documentation of C1q nephropathy, in mild form, complicating autosomal recessive Bartter syndrome. This case shows the importance of the renal biopsy and of molecular analysis in delineating the cause of atypical nephropathy associated with Bartter syndrome. These findings add to the evidence of a possible association between the congenital syndrome and acquired immune complex nephropathy.
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Affiliation(s)
- Yahya Sardani
- Department of Pediatrics, The University of Chicago Pritzker School of Medicine, 5839 S. Maryland Avenue, Chicago, IL 60637-1470, USA
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Gross P. Gitelman syndrome: when will it turn into Gitelman disease? Pediatr Nephrol 2003; 18:613-6. [PMID: 12728368 DOI: 10.1007/s00467-003-1171-8] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/03/2003] [Accepted: 03/25/2003] [Indexed: 12/28/2022]
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Meade P, Hoover RS, Plata C, Vázquez N, Bobadilla NA, Gamba G, Hebert SC. cAMP-dependent activation of the renal-specific Na+-K+-2Cl- cotransporter is mediated by regulation of cotransporter trafficking. Am J Physiol Renal Physiol 2003; 284:F1145-54. [PMID: 12604467 DOI: 10.1152/ajprenal.00421.2002] [Citation(s) in RCA: 51] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
The murine apical bumetanide-sensitive Na(+)-K(+)-2Cl(-) cotransporter gene (mBSC1) exhibits two spliced isoform products that differ at the COOH-terminal domain. A long COOH-terminal isoform (L-mBSC1) encodes the Na(+)-K(+)-2Cl(-) cotransporter, and a short isoform (S-mBSC1) exerts a dominant-negative effect on L-mBSC1 cotransporter activity that is abrogated by cAMP. However, the mechanism of this dominant-negative effect was not clear. In this study, we used confocal microscopic analysis of an enhanced green fluorescent protein (EGFP) fusion construct (L-mBSC1-EGFP) expressed to characterize the surface expression of the L-BSC1 isoform in Xenopus laevis oocytes. Functional expression was also assessed in L-mBSC1-injected oocytes by measuring the bumetanide-sensitive (86)Rb(+) uptake. Oocytes injected with L-mBSC1-EGFP cRNA developed a distinct plasma membrane-associated fluorescence that colocalized with the fluorescent membrane dye FM 4-64. The fluorescence intensity in L-mBSC1-EGFP oocytes did not change after cAMP was added to the extracellular medium. In contrast, L-mBSC1-EGFP fluorescence intensity was reduced in a dose-dependent manner, with coexpression of S-mBSC1. The inhibitory effect of S-mBSC1 was abrogated by cAMP. Finally, the exocytosis inhibitor colchicine blocked the effect of cAMP on the L-mBSC1-EGFP/S-mBSC1-coinjected oocytes. All changes in L-mBSC1 surface expression correlated with modification of bumetanide-sensitive (86)Rb(+) uptake. Our data suggest that the dominant-negative effect of S-mBSC1 on L-mBSC1 transport function is due to the effects of the cotransporter on trafficking.
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Affiliation(s)
- Patricia Meade
- Molecular Physiology Unit, Instituto de Investigaciones Biomédicas, Universidad Nacional Autónoma de México
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