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Wang Y, Li H, Huang Z, Yang S, Lu C, Zhang W, Zhao S, Yang C, Chen D. A novel variant in a Chinese boy with lysinuric protein intolerance: A case report and literature review. Heliyon 2024; 10:e27044. [PMID: 38444501 PMCID: PMC10912482 DOI: 10.1016/j.heliyon.2024.e27044] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/21/2023] [Revised: 12/13/2023] [Accepted: 02/22/2024] [Indexed: 03/07/2024] Open
Abstract
We report a case of a 4-year-old boy with lysinuric protein intolerance in China. The patient presented with interstitial lung disease with obvious clubbing of the fingers and toes. During the course of diagnosis and treatment, we found he was averse to a high-protein diet, intolerant to activity, and had a history of diarrhea and fractures. Physical examination revealed hepatosplenomegaly and clubbing of the fingers and toes. Next-generation sequencing revealed compound heterozygous mutations (c.1387delG, c.958T > C) in SLC7A7, which was confirmed as a disease-causing gene for lysinuric protein intolerance. After a literature review, we found that c.958T > C had not been previously reported, and summarized the clinical and genetic characteristics of patients from different continents. His symptoms improved significantly after 3 months of being on a low-protein diet, supplementation with lysine, citrulline, carnitine, and trace elements, and oral corticosteroid treatment for 2 months. The patient is still under follow-up.
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Affiliation(s)
- Yanhong Wang
- Department of Pediatrics, The First Affiliated Hospital of Guangzhou Medical University, Guangzhou, China
| | - Hongwei Li
- Department of Pediatrics, The First Affiliated Hospital of Guangzhou Medical University, Guangzhou, China
| | - Zhanhang Huang
- Department of Pediatrics, The First Affiliated Hospital of Guangzhou Medical University, Guangzhou, China
| | - Sen Yang
- Department of Pediatrics, The First Affiliated Hospital of Guangzhou Medical University, Guangzhou, China
| | - Chengyu Lu
- Department of Pediatrics, The First Affiliated Hospital of Guangzhou Medical University, Guangzhou, China
| | - Wei Zhang
- BGI Genomics, BGI-Shenzhen, Shenzhen, China
| | | | - Cui Yang
- Department of Pediatrics, The First Affiliated Hospital of Guangzhou Medical University, Guangzhou, China
| | - Dehui Chen
- Department of Pediatrics, The First Affiliated Hospital of Guangzhou Medical University, Guangzhou, China
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全 娇, 刘 小, 胡 可, 侯 茜. [Enteral nutrition support for lysinuric protein intolerance: a case report and literature review]. ZHONGGUO DANG DAI ER KE ZA ZHI = CHINESE JOURNAL OF CONTEMPORARY PEDIATRICS 2023; 25:1270-1275. [PMID: 38112146 PMCID: PMC10731975 DOI: 10.7499/j.issn.1008-8830.2306148] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Subscribe] [Scholar Register] [Received: 06/29/2023] [Accepted: 11/09/2023] [Indexed: 12/20/2023]
Abstract
OBJECTIVES To summarize the clinical characteristics and nutrition therapy for children with lysinuric protein intolerance (LPI). METHODS The clinical manifestations, laboratory test results and enteral nutrition treatment in a girl with LPI diagnosed in Xiangya Hospital, Central South University were retrospective analyzed. Additionally, the data of the children with LPI reported in China and overseas were reviewed. RESULTS A case of 4-year-old girl was presented, who exhibited significant gastrointestinal symptoms, such as chronic abdominal distension, prolonged diarrhea, recurrent pneumonia, and limited growth. She had a poor response to anti-infection treatment. After receiving enteral nutrition therapy, she did not experience any gastrointestinal discomfort, and there were improvements in the levels of hemoglobin, albumin, and blood ammonia. Unfortunately, due to serious illness, she declined further treatment and later passed away. A total of 92 cases of pediatric patients with LPI have been reported to date, including one case reported in this study. Most children with LPI experienced disease onset after weaning or introduction of complementary foods, presenting with severe digestive system symptoms, malnutrition, and growth retardation. It is noteworthy that only 50% (46/92) of these cases received nutritional therapy, which effectively improved their nutritional status. Among the 92 children, 8 (9%) died, and long-term follow-up data were lacking in other reports. CONCLUSIONS LPI often involves the digestive system and may result in growth restriction with a poor prognosis. Nutritional therapy plays a crucial role in the comprehensive treatment of LPI.
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Stroup BM, Li X, Ho S, Zhouyao H, Chen Y, Ani S, Dawson B, Jin Z, Marom R, Jiang MM, Lorenzo I, Rosen D, Lanza D, Aceves N, Koh S, Seavitt JR, Heaney JD, Lee B, Burrage LC. Delayed skeletal development and IGF-1 deficiency in a mouse model of lysinuric protein intolerance. Dis Model Mech 2023; 16:dmm050118. [PMID: 37486182 PMCID: PMC10445726 DOI: 10.1242/dmm.050118] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/07/2023] [Accepted: 07/14/2023] [Indexed: 07/25/2023] Open
Abstract
SLC7A7 deficiency, or lysinuric protein intolerance (LPI), causes loss of function of the y+LAT1 transporter critical for efflux of arginine, lysine and ornithine in certain cells. LPI is characterized by urea cycle dysfunction, renal disease, immune dysregulation, growth failure, delayed bone age and osteoporosis. We previously reported that Slc7a7 knockout mice (C57BL/6×129/SvEv F2) recapitulate LPI phenotypes, including growth failure. Our main objective in this study was to characterize the skeletal phenotype in these mice. Compared to wild-type littermates, juvenile Slc7a7 knockout mice demonstrated 70% lower body weights, 87% lower plasma IGF-1 concentrations and delayed skeletal development. Because poor survival prevents evaluation of mature knockout mice, we generated a conditional Slc7a7 deletion in mature osteoblasts or mesenchymal cells of the osteo-chondroprogenitor lineage, but no differences in bone architecture were observed. Overall, global Slc7a7 deficiency caused growth failure with low plasma IGF-1 concentrations and delayed skeletal development, but Slc7a7 deficiency in the osteoblastic lineage was not a major contributor to these phenotypes. Future studies utilizing additional tissue-specific Slc7a7 knockout models may help dissect cell-autonomous and non-cell-autonomous mechanisms underlying phenotypes in LPI.
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Affiliation(s)
- Bridget M. Stroup
- Department of Molecular and Human Genetics, Baylor College of Medicine, Houston, TX 77030, USA
| | - Xiaohui Li
- Department of Molecular and Human Genetics, Baylor College of Medicine, Houston, TX 77030, USA
| | - Sara Ho
- Department of Molecular and Human Genetics, Baylor College of Medicine, Houston, TX 77030, USA
| | - Haonan Zhouyao
- Department of Molecular and Human Genetics, Baylor College of Medicine, Houston, TX 77030, USA
| | - Yuqing Chen
- Department of Molecular and Human Genetics, Baylor College of Medicine, Houston, TX 77030, USA
| | - Safa Ani
- Department of Molecular and Human Genetics, Baylor College of Medicine, Houston, TX 77030, USA
| | - Brian Dawson
- Department of Molecular and Human Genetics, Baylor College of Medicine, Houston, TX 77030, USA
| | - Zixue Jin
- Department of Molecular and Human Genetics, Baylor College of Medicine, Houston, TX 77030, USA
| | - Ronit Marom
- Department of Molecular and Human Genetics, Baylor College of Medicine, Houston, TX 77030, USA
- Texas Children's Hospital, Houston, TX 77030, USA
| | - Ming-Ming Jiang
- Department of Molecular and Human Genetics, Baylor College of Medicine, Houston, TX 77030, USA
| | - Isabel Lorenzo
- Department of Molecular and Human Genetics, Baylor College of Medicine, Houston, TX 77030, USA
| | - Daniel Rosen
- Department of Pathology and Immunology, Baylor College of Medicine, Houston, TX 77030, USA
| | - Denise Lanza
- Department of Molecular and Human Genetics, Baylor College of Medicine, Houston, TX 77030, USA
| | - Nathalie Aceves
- Department of Molecular and Human Genetics, Baylor College of Medicine, Houston, TX 77030, USA
| | - Sara Koh
- Rice University, Houston, TX 77005, USA
| | - John R. Seavitt
- Department of Molecular and Human Genetics, Baylor College of Medicine, Houston, TX 77030, USA
| | - Jason D. Heaney
- Department of Molecular and Human Genetics, Baylor College of Medicine, Houston, TX 77030, USA
| | - Brendan Lee
- Department of Molecular and Human Genetics, Baylor College of Medicine, Houston, TX 77030, USA
| | - Lindsay C. Burrage
- Department of Molecular and Human Genetics, Baylor College of Medicine, Houston, TX 77030, USA
- Texas Children's Hospital, Houston, TX 77030, USA
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Contreras JL, Ladino MA, Aránguiz K, Mendez GP, Coban-Akdemir Z, Yuan B, Gibbs RA, Burrage LC, Lupski JR, Chinn IK, Vogel TP, Orange JS, Poli MC. Immune Dysregulation Mimicking Systemic Lupus Erythematosus in a Patient With Lysinuric Protein Intolerance: Case Report and Review of the Literature. Front Pediatr 2021; 9:673957. [PMID: 34095032 PMCID: PMC8172984 DOI: 10.3389/fped.2021.673957] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/28/2021] [Accepted: 04/14/2021] [Indexed: 12/14/2022] Open
Abstract
Lysinuric protein intolerance (LPI) is an inborn error of metabolism caused by defective transport of cationic amino acids in epithelial cells of intestines, kidneys and other tissues as well as non-epithelial cells including macrophages. LPI is caused by biallelic, pathogenic variants in SLC7A7. The clinical phenotype of LPI includes failure to thrive and multi-system disease including hematologic, neurologic, pulmonary and renal manifestations. Individual presentations are extremely variable, often leading to misdiagnosis or delayed diagnosis. Here we describe a patient that clinically presented with immune dysregulation in the setting of early-onset systemic lupus erythematosus (SLE), including renal involvement, in whom an LPI diagnosis was suspected post-mortem based on exome sequencing analysis. A review of the literature was performed to provide an overview of the clinical spectrum and immune mechanisms involved in this disease. The precise mechanism by which ineffective amino acid transport triggers systemic inflammatory features is not yet understood. However, LPI should be considered in the differential diagnosis of early-onset SLE, particularly in the absence of response to immunosuppressive therapy.
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Affiliation(s)
| | - Mabel A. Ladino
- Universidad de Chile, Reumatóloga Pediátrica Hospital San Juan de Dios, Santiago, Chile
| | - Katherine Aránguiz
- Unidad de Inmunología y Reumatología Hospital Luis Calvo Mackenna, Providencia, Chile
| | - Gonzalo P. Mendez
- Patológo Renal, Departamento de Anatomía Patológica, Facultad de Medicina, Pontificia Universidad Católica de Chile, Santiago, Chile
| | - Zeynep Coban-Akdemir
- Department of Molecular and Human Genetics, Baylor College of Medicine, Houston, TX, United States
- Human Genetics Center, Department of Epidemiology, Human Genetics, and Environmental Sciences, School of Public Health, The University of Texas Health Science Center at Houston, Houston, TX, United States
| | - Bo Yuan
- Department of Laboratories, Seattle Children's Hospital, Seattle, WA, United States
- Department of Laboratory Medicine and Pathology, University of Washington, Seattle, WA, United States
| | - Richard A. Gibbs
- Sequencing Center, Baylor College of Medicine, Houston, TX, United States
| | - Lindsay C. Burrage
- Department of Molecular and Human Genetics, Baylor College of Medicine, Houston, TX, United States
- Texas Children's Hospital, Houston, TX, United States
| | - James R. Lupski
- Department of Molecular and Human Genetics, Baylor College of Medicine, Houston, TX, United States
- Sequencing Center, Baylor College of Medicine, Houston, TX, United States
- Texas Children's Hospital, Houston, TX, United States
| | - Ivan K. Chinn
- Texas Children's Hospital, Houston, TX, United States
- Department of Pediatrics, Division of Allergy, Immunology and Retrovirology, Baylor College of Medicine, Houston, TX, United States
| | - Tiphanie P. Vogel
- Texas Children's Hospital, Houston, TX, United States
- Department of Pediatrics, Division of Rheumatology, Baylor College of Medicine, Houston, TX, United States
| | - Jordan S. Orange
- Department of Pediatrics, Vagelos College of Physicians and Surgeons, New York Presbyterian Morgan Stanley Children's Hospital, Columbia University, New York, NY, United States
| | - M. Cecilia Poli
- Facultad de Medicina Universidad del Desarrollo-Clínica Alemana, Santiago, Chile
- Department of Pediatrics, Division of Allergy, Immunology and Retrovirology, Baylor College of Medicine, Houston, TX, United States
- Unidad de Inmunología y Reumatología, Hospital Roberto del Río, Santiago, Chile
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Stroup BM, Marom R, Li X, Hsu CW, Chang CY, Truong LD, Dawson B, Grafe I, Chen Y, Jiang MM, Lanza D, Green JR, Sun Q, Barrish JP, Ani S, Christiansen AE, Seavitt JR, Dickinson ME, Kheradmand F, Heaney JD, Lee B, Burrage LC. A global Slc7a7 knockout mouse model demonstrates characteristic phenotypes of human lysinuric protein intolerance. Hum Mol Genet 2020; 29:2171-2184. [PMID: 32504080 PMCID: PMC7399531 DOI: 10.1093/hmg/ddaa107] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/08/2020] [Revised: 04/30/2020] [Accepted: 05/19/2020] [Indexed: 12/18/2022] Open
Abstract
Lysinuric protein intolerance (LPI) is an inborn error of cationic amino acid (arginine, lysine, ornithine) transport caused by biallelic pathogenic variants in SLC7A7, which encodes the light subunit of the y+LAT1 transporter. Treatments for the complications of LPI, including growth failure, renal disease, pulmonary alveolar proteinosis, autoimmune disorders and osteoporosis, are limited. Given the early lethality of the only published global Slc7a7 knockout mouse model, a viable animal model to investigate global SLC7A7 deficiency is needed. Hence, we generated two mouse models with global Slc7a7 deficiency (Slc7a7em1Lbu/em1Lbu; Slc7a7Lbu/Lbu and Slc7a7em1(IMPC)Bay/em1(IMPC)Bay; Slc7a7Bay/Bay) using CRISPR/Cas9 technology by introducing a deletion of exons 3 and 4. Perinatal lethality was observed in Slc7a7Lbu/Lbu and Slc7a7Bay/Bay mice on the C57BL/6 and C57BL/6NJ inbred genetic backgrounds, respectively. We noted improved survival of Slc7a7Lbu/Lbu mice on the 129 Sv/Ev × C57BL/6 F2 background, but postnatal growth failure occurred. Consistent with human LPI, these Slc7a7Lbu/Lbu mice exhibited reduced plasma and increased urinary concentrations of the cationic amino acids. Histopathological assessment revealed loss of brush border and lipid vacuolation in the renal cortex of Slc7a7Lbu/Lbu mice, which combined with aminoaciduria suggests proximal tubular dysfunction. Micro-computed tomography of L4 vertebrae and skeletal radiographs showed delayed skeletal development and suggested decreased mineralization in Slc7a7Lbu/Lbu mice, respectively. In addition to delayed skeletal development and delayed development in the kidneys, the lungs and liver were observed based on histopathological assessment. Overall, our Slc7a7Lbu/Lbu mouse model on the F2 mixed background recapitulates multiple human LPI phenotypes and may be useful for future studies of LPI pathology.
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Affiliation(s)
- Bridget M Stroup
- Department of Molecular and Human Genetics, Baylor College of Medicine, Houston, TX 77030, USA
| | - Ronit Marom
- Department of Molecular and Human Genetics, Baylor College of Medicine, Houston, TX 77030, USA
- Texas Children's Hospital, Houston, TX 77030, USA
| | - Xiaohui Li
- Department of Molecular and Human Genetics, Baylor College of Medicine, Houston, TX 77030, USA
| | - Chih-Wei Hsu
- Department of Molecular Physiology and Biophysics, Baylor College of Medicine, Houston, TX 77030, USA
| | - Cheng-Yen Chang
- Department of Medicine-Pulmonary, Baylor College of Medicine, Houston, TX 77030, USA
| | - Luan D Truong
- Department of Pathology and Genomic Medicine, Houston Methodist Hospital, Houston, TX 77030, USA
| | - Brian Dawson
- Department of Molecular and Human Genetics, Baylor College of Medicine, Houston, TX 77030, USA
| | - Ingo Grafe
- Department of Molecular and Human Genetics, Baylor College of Medicine, Houston, TX 77030, USA
- Division of Endocrinology, Diabetes, and Bone Diseases, Department of Medicine III, Center for Healthy Aging, University Clinic, Dresden D-01307, Germany
| | - Yuqing Chen
- Department of Molecular and Human Genetics, Baylor College of Medicine, Houston, TX 77030, USA
| | - Ming-Ming Jiang
- Department of Molecular and Human Genetics, Baylor College of Medicine, Houston, TX 77030, USA
| | - Denise Lanza
- Department of Molecular and Human Genetics, Baylor College of Medicine, Houston, TX 77030, USA
| | - Jennie Rose Green
- Department of Molecular and Human Genetics, Baylor College of Medicine, Houston, TX 77030, USA
| | - Qin Sun
- Department of Molecular and Human Genetics, Baylor College of Medicine, Houston, TX 77030, USA
- Baylor Genetics, Houston, TX 77021, USA
| | - J P Barrish
- Department of Pathology, Texas Children's Hospital, Baylor College of Medicine, Houston, TX 77030, USA
| | - Safa Ani
- Department of Molecular and Human Genetics, Baylor College of Medicine, Houston, TX 77030, USA
| | - Audrey E Christiansen
- Department of Molecular Physiology and Biophysics, Baylor College of Medicine, Houston, TX 77030, USA
| | - John R Seavitt
- Department of Molecular and Human Genetics, Baylor College of Medicine, Houston, TX 77030, USA
| | - Mary E Dickinson
- Department of Molecular Physiology and Biophysics, Baylor College of Medicine, Houston, TX 77030, USA
| | - Farrah Kheradmand
- Department of Medicine-Pulmonary, Baylor College of Medicine, Houston, TX 77030, USA
| | - Jason D Heaney
- Department of Molecular and Human Genetics, Baylor College of Medicine, Houston, TX 77030, USA
| | - Brendan Lee
- Department of Molecular and Human Genetics, Baylor College of Medicine, Houston, TX 77030, USA
| | - Lindsay C Burrage
- Department of Molecular and Human Genetics, Baylor College of Medicine, Houston, TX 77030, USA
- Texas Children's Hospital, Houston, TX 77030, USA
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Alqarajeh F, Omorodion J, Bosfield K, Shur N, Ferreira CR. Lysinuric protein intolerance: Pearls to detect this otherwise easily missed diagnosis. ACTA ACUST UNITED AC 2020; 5:81-86. [PMID: 33134088 PMCID: PMC7590902 DOI: 10.3233/trd-190035] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/30/2022]
Abstract
BACKGROUND: Lysinuric protein intolerance (LPI) is a rare autosomal recessive disorder characterized by deficient membrane transport of cationic amino acids. It is caused by pathogenic variants in SLC7A7, resulting in impairment of intestinal import and renal proximal tubule loss of the affected amino acids. LPI typically presents with gastrointestinal symptoms, such as vomiting, diarrhea, and failure to thrive. CASE REPORT: A 4-year-old African-American boy presented with multiple respiratory tract infections, weight loss in the setting of chronic diarrhea and worsening abdominal distention, and multiple episodes of rectal prolapse. Development was unaffected. Laboratory examination demonstrated mild anemia, hypokalemia and hypoalbuminemia, transaminitis, and normal ammonia. Initial urine amino acid analysis did not show major elevations of lysine and ornithine, often lower than expected in the setting of malnutrition. Upon initiation of total parenteral nutrition (TPN), his urine amino acids showed a characteristic profile of dibasic aminoaciduria. CONCLUSIONS: Failure to thrive, chronic diarrhea, and hepatomegaly should raise suspicion for LPI. Urine amino acids can be normal in this condition in the setting of malnutrition, a common complication of the disease. Additionally, it has been previously shown that the plasma arginine and ornithine concentration is higher in LPI subjects.
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Affiliation(s)
- Firas Alqarajeh
- Faculty of Medicine, Al-Quds University, Jerusalem, Palestine
| | - Jacklyn Omorodion
- The George Washington University School of Medicine and Health Sciences, Washington, DC, USA
| | - Kerri Bosfield
- Rare Disease Institute, Children's National Health System, Washington, DC, USA
| | - Natasha Shur
- Rare Disease Institute, Children's National Health System, Washington, DC, USA
| | - Carlos R Ferreira
- National Human Genome Research Institute, National Institutes of Health, Bethesda, MD, USA
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Lysinuric protein intolerance with homozygous SLC7A7 mutation caused by maternal uniparental isodisomy of chromosome 14. J Hum Genet 2019; 64:1137-1140. [PMID: 31427715 DOI: 10.1038/s10038-019-0657-6] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/13/2019] [Revised: 07/19/2019] [Accepted: 08/02/2019] [Indexed: 11/08/2022]
Abstract
Lysinuric protein intolerance (LPI) is caused by mutations in the SLC7A7 gene at 14q11.2. Its clinical presentation includes failure to thrive, protein intolerance due to a secondary urea cycle defect, interstitial lung disease, renal tubulopathy, and immune disorders. Maternal uniparental disomy 14 (UPD14mat) is the most common cause of Temple syndrome (TS14), which is characterized by severe intrauterine and postnatal growth failure. Here, we describe a severe form of LPI accompanied by TS14 in an 11-month-old girl, which presented as profound failure to thrive and delayed development. LPI was diagnosed by the detection of a homozygous mutation of c.713 C>T (p.Ser238Phe) in SLC7A7, which was eventually found to co-occur with UPD14mat. Despite receiving a protein-restricted diet with citrulline and lysine supplementation, the severe failure to thrive has persisted at follow-up of the patient at 4 years of age.
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Noguchi A, Takahashi T. Overview of symptoms and treatment for lysinuric protein intolerance. J Hum Genet 2019; 64:849-858. [PMID: 31213652 DOI: 10.1038/s10038-019-0620-6] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/03/2018] [Revised: 05/16/2019] [Accepted: 05/16/2019] [Indexed: 12/30/2022]
Abstract
Lysinuric protein intolerance (LPI) is caused by dysfunction of the dibasic amino acid membrane transport owing to the functional abnormality of y+L amino acid transporter-1 (y+ LAT-1). LPI is associated with autosomal recessive inheritance and pathological variants in the responsible gene SLC7A7 are also observed. The pathophysiology of this disease had earlier been understood as a transport defect in polarized cells (e.g., intestinal or renal tubular epithelium); however, in recent years, transport defects in non-polarized cells such as lymphocytes and macrophages have also been recognized as important. Although the former can cause death, malnutrition, and urea cycle dysfunction (hyperammonemia), the latter can induce renal, pulmonary, and immune disorders. Furthermore, although therapeutic interventions can prevent hyperammonemic episodes to some extent, progression of pulmonary and renal complications cannot be prevented, thereby influencing prognosis. Such pathological conditions are currently being explored and further investigation would prove beneficial. In this study, we have summarized the basic pathology as revealed in recent years, along with the clinical aspects and genetic features.
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Affiliation(s)
- Atsuko Noguchi
- Akita University Graduate School of Medicine, Pediatrics, Akita, Akita, Japan.
| | - Tsutomu Takahashi
- Akita University Graduate School of Medicine, Pediatrics, Akita, Akita, Japan
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