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Kingma SDK, Neven J, Bael A, Meuwissen MEC, van den Akker M. Imerslund-Gräsbeck syndrome: a comprehensive review of reported cases. Orphanet J Rare Dis 2023; 18:291. [PMID: 37710296 PMCID: PMC10500774 DOI: 10.1186/s13023-023-02889-x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/17/2023] [Accepted: 08/25/2023] [Indexed: 09/16/2023] Open
Abstract
Imerslund-Gräsbeck syndrome (IGS) is a rare autosomal recessive disorder characterized by vitamin B12 malabsorption. Most patients present with non-specific symptoms attributed to vitamin B12 deficiency, and proteinuria. Patients may if untreated, develop severe neurocognitive manifestations. If recognized and treated with sufficient doses of vitamin B12, patients recover completely. We provide, for the first time, an overview of all previously reported cases of IGS. In addition, we provide a complete review of IGS and describe two new patients.
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Affiliation(s)
- Sandra D K Kingma
- Centre for Metabolic Diseases, University Hospital Antwerp, University of Antwerp, Drie Eikenstraat 655, Edegem, Antwerp, 2650, Belgium
- Department of Pediatrics, University Hospital Antwerp, University of Antwerp, Drie Eikenstraat 655, Edegem, 2650, Belgium
- Faculty of medicine and health sciences, University of Antwerp, Antwerp, Belgium
| | - Julie Neven
- Department of Pediatrics, University Hospital Antwerp, University of Antwerp, Drie Eikenstraat 655, Edegem, 2650, Belgium
| | - An Bael
- Faculty of medicine and health sciences, University of Antwerp, Antwerp, Belgium
- Department of Pediatric Nephrology, ZNA Queen Paola Children's Hospital, Lindendreef 1, Antwerp, 2020, Belgium
| | - Marije E C Meuwissen
- Center of Medical Genetics, University Hospital Antwerp, Drie Eikenstraat 655, Edegem, 2650, Belgium
| | - Machiel van den Akker
- Department of Pediatrics, University Hospital Antwerp, University of Antwerp, Drie Eikenstraat 655, Edegem, 2650, Belgium.
- Faculty of medicine and health sciences, University of Antwerp, Antwerp, Belgium.
- Department of Pediatrics, ZNA Queen Paola Children's Hospital, Lindendreef 1, Antwerp, 2020, Belgium.
- Pediatric Hematology and Oncology, Department of Pediatrics, University Hospital Antwerp, Drie Eikenstraat 655, Edegem, Antwerp, 2650, Belgium.
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Elangovan R, Baruteau J. Inherited and acquired vitamin B12 deficiencies: Which administration route to choose for supplementation? Front Pharmacol 2022; 13:972468. [PMID: 36249776 PMCID: PMC9559827 DOI: 10.3389/fphar.2022.972468] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/18/2022] [Accepted: 08/23/2022] [Indexed: 11/13/2022] Open
Abstract
Vitamin B12 or cobalamin deficiency is a commonly encountered clinical scenario and most clinicians will have familiarity prescribing Vitamin B12 to treat their patients. Despite the high prevalence of this condition, there is widespread heterogeneity regarding routes, schedules and dosages of vitamin B12 administration. In this review, we summarise the complex metabolic pathway of Vitamin B12, the inherited and acquired causes of Vitamin B12 deficiency and subsequently highlight the disparate international practice of prescribing Vitamin B12 replacement therapy. We describe the evidence base underpinning the novel sublingual, intranasal and subcutaneous modes of B12 replacement in comparison to intramuscular and oral routes, with their respective benefits for patient compliance and cost-saving.
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Affiliation(s)
- Ramyia Elangovan
- Metabolic Medicine Department, Great Ormond Street Hospital for Children NHS Foundation Trust, London, United Kingdom
| | - Julien Baruteau
- Metabolic Medicine Department, Great Ormond Street Hospital for Children NHS Foundation Trust, London, United Kingdom
- Genetics and Genomic Medicine Department, Great Ormond Street Institute of Child Health, University College London, London, United Kingdom
- National Institute of Health Research Great Ormond Street Biomedical Research Centre, London, United Kingdom
- *Correspondence: Julien Baruteau,
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Joseph FD, Campbell DR, Cohn S, Roach ES. A Child with Falls, Fatigue, and Dementia. Pediatr Rev 2022; 43:466-468. [PMID: 35909134 DOI: 10.1542/pir.2020-003053] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
Affiliation(s)
- Freddie D Joseph
- Division of Child Neurology, Dell Children's Medical Center, Austin, TX
| | - Damian R Campbell
- Division of Child Neurology, University of Texas Dell Medical School, Austin, TX
| | - Shannon Cohn
- Division of Hematology/Oncology, Dell Children's Medical Center, Austin, TX
| | - E Steve Roach
- Department of Neurology, University of Texas Dell Medical School, Austin, TX
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Wiedemann A, Oussalah A, Lamireau N, Théron M, Julien M, Mergnac JP, Augay B, Deniaud P, Alix T, Frayssinoux M, Feillet F, Guéant JL. Clinical, phenotypic and genetic landscape of case reports with genetically proven inherited disorders of vitamin B 12 metabolism: A meta-analysis. Cell Rep Med 2022; 3:100670. [PMID: 35764087 PMCID: PMC9381384 DOI: 10.1016/j.xcrm.2022.100670] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/14/2021] [Revised: 11/22/2021] [Accepted: 06/02/2022] [Indexed: 10/31/2022]
Abstract
Inherited disorders of B12 metabolism produce a broad spectrum of manifestations, with limited knowledge of the influence of age and the function of related genes. We report a meta-analysis on 824 patients with a genetically proven diagnosis of an inherited disorder of vitamin B12 metabolism. Gene clusters and age categories are associated with patients' manifestations. The "cytoplasmic transport" cluster is associated with neurological and ophthalmological manifestations, the "mitochondrion" cluster with hypotonia, acute metabolic decompensation, and death, and the "B12 availability" and "remethylation" clusters with anemia and cytopenia. Hypotonia, EEG abnormalities, nystagmus, and strabismus are predominant in the younger patients, while neurological manifestations, such as walking difficulties, peripheral neuropathy, pyramidal syndrome, cerebral atrophy, psychiatric disorders, and thromboembolic manifestations, are predominant in the older patients. These results should prompt systematic checking of markers of vitamin B12 status, including homocysteine and methylmalonic acid, when usual causes of these manifestations are discarded in adult patients.
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Affiliation(s)
- Arnaud Wiedemann
- Nutrition, Genetics, and Environmental Risk Exposure (NGERE), Faculty of Medicine of Nancy, University of Lorraine, INSERM UMR_S 1256, 54000 Nancy, France; Department of Pediatrics, University Hospital of Nancy, 54000 Nancy, France; Reference Center for Inborn Errors of Metabolism (ORPHA67872), University Hospital of Nancy, 54000 Nancy, France
| | - Abderrahim Oussalah
- Nutrition, Genetics, and Environmental Risk Exposure (NGERE), Faculty of Medicine of Nancy, University of Lorraine, INSERM UMR_S 1256, 54000 Nancy, France; Reference Center for Inborn Errors of Metabolism (ORPHA67872), University Hospital of Nancy, 54000 Nancy, France; Department of Molecular Medicine, Division of Biochemistry, Molecular Biology, Nutrition, and Metabolism, University Hospital of Nancy, 54000 Nancy, France
| | - Nathalie Lamireau
- Department of Pediatrics, University Hospital of Nancy, 54000 Nancy, France
| | - Maurane Théron
- Department of Pediatrics, University Hospital of Nancy, 54000 Nancy, France
| | - Melissa Julien
- Department of Molecular Medicine, Division of Biochemistry, Molecular Biology, Nutrition, and Metabolism, University Hospital of Nancy, 54000 Nancy, France
| | | | - Baptiste Augay
- Department of Pediatrics, University Hospital of Nancy, 54000 Nancy, France
| | - Pauline Deniaud
- Department of Pediatrics, University Hospital of Nancy, 54000 Nancy, France
| | - Tom Alix
- Department of Molecular Medicine, Division of Biochemistry, Molecular Biology, Nutrition, and Metabolism, University Hospital of Nancy, 54000 Nancy, France
| | - Marine Frayssinoux
- Department of Molecular Medicine, Division of Biochemistry, Molecular Biology, Nutrition, and Metabolism, University Hospital of Nancy, 54000 Nancy, France
| | - François Feillet
- Nutrition, Genetics, and Environmental Risk Exposure (NGERE), Faculty of Medicine of Nancy, University of Lorraine, INSERM UMR_S 1256, 54000 Nancy, France; Department of Pediatrics, University Hospital of Nancy, 54000 Nancy, France; Reference Center for Inborn Errors of Metabolism (ORPHA67872), University Hospital of Nancy, 54000 Nancy, France
| | - Jean-Louis Guéant
- Nutrition, Genetics, and Environmental Risk Exposure (NGERE), Faculty of Medicine of Nancy, University of Lorraine, INSERM UMR_S 1256, 54000 Nancy, France; Reference Center for Inborn Errors of Metabolism (ORPHA67872), University Hospital of Nancy, 54000 Nancy, France; Department of Molecular Medicine, Division of Biochemistry, Molecular Biology, Nutrition, and Metabolism, University Hospital of Nancy, 54000 Nancy, France.
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Baker KM, Parikh NS, Salsbery KT, Shaw GR, Steiner RD, Oelstrom MJ, Manalang MA. A 17-Month-old Boy With Pancytopenia Caused by a Rare Genetic Defect of Vitamin B12 Malabsorption. J Pediatr Hematol Oncol 2022; 44:e444-e446. [PMID: 34054045 DOI: 10.1097/mph.0000000000002213] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/21/2021] [Accepted: 04/25/2021] [Indexed: 11/26/2022]
Abstract
Imerslund-Gräsbeck syndrome is an autosomal recessive disorder of vitamin B12 malabsorption presenting with megaloblastic anemia and mild proteinuria in childhood. The disorder is caused by biallelic pathogenic variants in the CUBN or AMN genes, which encode proteins involved in B12 absorption. We present the case of a 17-month-old boy with failure to thrive, pancytopenia, and fevers. His megaloblastic anemia was overlooked leading to unnecessary invasive testing. Findings on bone marrow biopsy prompted investigation for genetic disorders of B12 metabolism. Exome sequencing uncovered 1 known pathogenic variant and 1 novel likely pathogenic variant in CUBN, confirming the diagnosis of Imerslund-Gräsbeck syndrome.
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Affiliation(s)
| | | | | | | | - Robert D Steiner
- Pediatrics and Prevention Genetics LLC
- Department of Pediatrics, University of Wisconsin School of Medicine and Public Health, Madison, WI
| | - Matthew J Oelstrom
- Pediatric Intensive Care Unit, Marshfield Children's Hospital, Marshfield
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Piquereau J, Boitard SE, Ventura-Clapier R, Mericskay M. Metabolic Therapy of Heart Failure: Is There a Future for B Vitamins? Int J Mol Sci 2021; 23:30. [PMID: 35008448 PMCID: PMC8744601 DOI: 10.3390/ijms23010030] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/03/2021] [Revised: 12/14/2021] [Accepted: 12/20/2021] [Indexed: 01/17/2023] Open
Abstract
Heart failure (HF) is a plague of the aging population in industrialized countries that continues to cause many deaths despite intensive research into more effective treatments. Although the therapeutic arsenal to face heart failure has been expanding, the relatively short life expectancy of HF patients is pushing towards novel therapeutic strategies. Heart failure is associated with drastic metabolic disorders, including severe myocardial mitochondrial dysfunction and systemic nutrient deprivation secondary to severe cardiac dysfunction. To date, no effective therapy has been developed to restore the cardiac energy metabolism of the failing myocardium, mainly due to the metabolic complexity and intertwining of the involved processes. Recent years have witnessed a growing scientific interest in natural molecules that play a pivotal role in energy metabolism with promising therapeutic effects against heart failure. Among these molecules, B vitamins are a class of water soluble vitamins that are directly involved in energy metabolism and are of particular interest since they are intimately linked to energy metabolism and HF patients are often B vitamin deficient. This review aims at assessing the value of B vitamin supplementation in the treatment of heart failure.
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Affiliation(s)
- Jérôme Piquereau
- UMR-S 1180, Inserm Unit of Signaling and Cardiovascular Pathophysiology, Faculty of Pharmacy, Université Paris-Saclay, 92296 Chatenay-Malabry, France; (S.E.B.); (R.V.-C.)
| | | | | | - Mathias Mericskay
- UMR-S 1180, Inserm Unit of Signaling and Cardiovascular Pathophysiology, Faculty of Pharmacy, Université Paris-Saclay, 92296 Chatenay-Malabry, France; (S.E.B.); (R.V.-C.)
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Elshinawy M, Gao HH, Al-Nabhani DM, Al-Thihli KA. Clinical and molecular characteristics of imerslund-gräsbeck syndrome: First report of a novel Frameshift variant in Exon 11 of AMN gene. Int J Lab Hematol 2021; 43:1009-1015. [PMID: 33491342 DOI: 10.1111/ijlh.13473] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/11/2020] [Revised: 12/06/2020] [Accepted: 12/30/2020] [Indexed: 11/30/2022]
Abstract
INTRODUCTION Imerslund-Gräsbeck syndrome (IGS) is a rare autosomal-recessive disorder characterized by selective vitamin B12 malabsorption, megaloblastic anemia, and proteinuria. The precise incidence of this disorder is unknown in the Middle East and Arab countries. The disease is caused by a homozygous variant in either AMN or CUBN genes. In addition, some compound heterozygous variants are reported. METHODS Clinical and laboratory data of patients diagnosed with IGS in Oman were retrospectively collected. Mutation analysis for all genes involved in vitamin B12/folic acid metabolism and megaloblastic anemia was conducted using next-generation sequencing (NGS). RESULTS Three siblings (2 girls and a boy) have been diagnosed with the condition. They exhibit a phenotypic variability with different age of presentation and different spectrum of disease. All patients harbor a novel biallelic frameshift mutation in exon 11 of AMN gene (p.Pro409Glyfs*), which was not reported previously in the literature. Both parents are heterozygotes for the same variant. All patients responded well to vitamin B12 parenteral therapy, but proteinuria persisted. CONCLUSION In communities with high incidence of consanguinity, cases of early-onset vitamin B12 deficiency should be thoroughly investigated to explore the possibility of Imerslund-Gräsbeck syndrome and other vitamin B12-related hereditary disorders. Further local and regional studies are highly recommended.
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Affiliation(s)
- Mohamed Elshinawy
- Department of Child Health, Pediatric Hematology/Oncology, Sultan Qaboos University Hospital, Muscat, Oman.,Department of Pediatrics, Pediatric Hematology/Oncology, Faculty of Medicine, University of Alexandria, Alexandria, Egypt
| | | | - Dana M Al-Nabhani
- Department of Nephrology, Sultan Qaboos University Hospital, Muscat, Oman
| | - Khalid A Al-Thihli
- Genetic and developmental Medicine Department, Sultan Qaboos University Hospital, Muscat, Oman
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Ruan J, Han B, Zhuang J, Chen M, Chen F, Huang Y, Zhou W. Hereditary intrinsic factor deficiency in China caused by a novel mutation in the intrinsic factor gene-a case report. BMC MEDICAL GENETICS 2020; 21:221. [PMID: 33172407 PMCID: PMC7654184 DOI: 10.1186/s12881-020-01158-z] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 07/22/2019] [Accepted: 10/27/2020] [Indexed: 11/10/2022]
Abstract
Background Hereditary intrinsic factor deficiency is a rare disease characterized by cobalamin deficiency with the lack of gastric intrinsic factor because of gastric intrinsic factor (GIF) mutations. Patients usually present with cobalamin deficiency without gastroscopy abnormality and intrinsic factor antibodies. Case presentation A Chinese patient presented with recurrent severe anemia since age 2 with low cobalamin level and a mild elevation of indirect bilirubin. The hemoglobin level normalized each time after intramuscular vitamin B12 injection. Gene test verified a c.776delA frame shift mutation in exon 6 combined with c.585C > A nonsense early termination mutation in exon 5 of GIF which result in the dysfunction of gastric intrinsic factor protein. The hereditary intrinsic factor deficiency in literature was further reviewed and the ancestry of different mutation sites were discussed. Conclusions A novel compound heterozygous mutation of GIF in a Chinese patient of hereditary intrinsic factor deficiency was reported. It was the first identified mutation of GIF in East-Asia and may indicate a new ancestry.
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Affiliation(s)
- Jing Ruan
- Department of Hematology, Peking Union Medical College, Hospital, Chinese Academy of Medical Sciences, No.1 Shuaifuyuan, Dongcheng District, Beijing, 100730, China
| | - Bing Han
- Department of Hematology, Peking Union Medical College, Hospital, Chinese Academy of Medical Sciences, No.1 Shuaifuyuan, Dongcheng District, Beijing, 100730, China.
| | - Junling Zhuang
- Department of Hematology, Peking Union Medical College, Hospital, Chinese Academy of Medical Sciences, No.1 Shuaifuyuan, Dongcheng District, Beijing, 100730, China
| | - Miao Chen
- Department of Hematology, Peking Union Medical College, Hospital, Chinese Academy of Medical Sciences, No.1 Shuaifuyuan, Dongcheng District, Beijing, 100730, China
| | - Fangfei Chen
- Department of Hematology, Peking Union Medical College, Hospital, Chinese Academy of Medical Sciences, No.1 Shuaifuyuan, Dongcheng District, Beijing, 100730, China
| | - Yuzhou Huang
- Department of Hematology, Peking Union Medical College, Hospital, Chinese Academy of Medical Sciences, No.1 Shuaifuyuan, Dongcheng District, Beijing, 100730, China
| | - Wenzhe Zhou
- Department of Hematology, Peking Union Medical College, Hospital, Chinese Academy of Medical Sciences, No.1 Shuaifuyuan, Dongcheng District, Beijing, 100730, China
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Chen RY, Li XZ, Lin Q, Zhu Y, Shen YY, Xu QY, Zhu XM, Chen LQ, Wu HY, Chen XQ. Proteinuria as a presenting sign of combined methylmalonic acidemia and homocysteinemia: case report. BMC MEDICAL GENETICS 2020; 21:183. [PMID: 32957924 PMCID: PMC7507264 DOI: 10.1186/s12881-020-01122-x] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 09/13/2019] [Accepted: 09/10/2020] [Indexed: 11/24/2022]
Abstract
Background Disorders of the metabolism and absorption of vitamin B12 can lead to decrease in activity of methionine synthetase and methylmalonate coenzyme A mutase (MMUT), which results in increased levels of methylmalonic acid and homocysteine in blood and urine. Often, combined methylmalonic acidemia (MMA) and homocysteinemia is misdiagnosed due to a lack of specific symptoms. The clinical manifestations are diverse, but proteinuria as the initial presentation is rare. Case presentation Two cases of MMA with homocysteinemia in children are reported. Proteinuria were a primary presenting symptom, followed by anemia and neurologic symptoms (frequent convulsions and unstable walking, respectively). Screening of amino acids and acyl carnitine in serum showed that the propionyl carnitine:acetylcarnitine ratio increased. Profiling of urinary organic acids by gas chromatography–mass spectrometry revealed high levels of methylmalonic acid. Homocysteine content in blood was increased. Comprehensive genetic analyses of peripheral blood-derived DNA demonstrated heterozygous variants of methylmalonic aciduria type C and homocystinuria (MMACHC) and amnionless (AMN) genes in our two patients, respectively. After active treatment, the clinical manifestations in Case 1 were relieved and urinary protein ceased to be observed; Case 2 had persistent proteinuria and was lost to follow-up. Conclusions Analyses of the organic acids in blood and urine suggested MMA combined with homocysteinemia. In such diseases, reports of renal damage are uncommon and proteinuria as the initial presentation is rare. Molecular analysis indicated two different genetic causes. Although the pathologic mechanisms were related to vitamin B12, the severity and prognosis of renal lesions were different. Therefore, gene detection provides new insights into inherited metabolic diseases.
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Affiliation(s)
- Ru-Yue Chen
- Department of Nephrology and Immunology, Children's Hospital of Soochow University, Suzhou, Jiangsu, China
| | - Xiao-Zhong Li
- Department of Nephrology and Immunology, Children's Hospital of Soochow University, Suzhou, Jiangsu, China.
| | - Qiang Lin
- Department of Nephrology and Immunology, Children's Hospital of Soochow University, Suzhou, Jiangsu, China
| | - Yun Zhu
- Department of Nephrology and Immunology, Children's Hospital of Soochow University, Suzhou, Jiangsu, China
| | - Yun-Yan Shen
- Department of Nephrology and Immunology, Children's Hospital of Soochow University, Suzhou, Jiangsu, China
| | - Qin-Ying Xu
- Department of Nephrology and Immunology, Children's Hospital of Soochow University, Suzhou, Jiangsu, China
| | - Xue-Ming Zhu
- Department of Pathology, Children's Hospital of Soochow University, Suzhou, Jiangsu, China
| | - Lin-Qi Chen
- Department of Endocrinology, Children's Hospital of Soochow University, Suzhou, Jiangsu, China
| | - Hai-Ying Wu
- Department of Endocrinology, Children's Hospital of Soochow University, Suzhou, Jiangsu, China
| | - Xu-Qin Chen
- Department of Neurology, Children's Hospital of Soochow University, Suzhou, Jiangsu, China
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Huemer M, Baumgartner MR. The clinical presentation of cobalamin-related disorders: From acquired deficiencies to inborn errors of absorption and intracellular pathways. J Inherit Metab Dis 2019; 42:686-705. [PMID: 30761552 DOI: 10.1002/jimd.12012] [Citation(s) in RCA: 35] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/11/2018] [Revised: 09/25/2018] [Accepted: 09/27/2018] [Indexed: 12/11/2022]
Abstract
This review gives an overview of clinical characteristics, treatment and outcome of nutritional and acquired cobalamin (Cbl; synonym: vitamin B12) deficiencies, inborn errors of Cbl absorption and intracellular trafficking, as well as methylenetetrahydrofolate dehydrogenase (MTHFD1) and methylene tetrahydrofolate reductase (MTHFR) deficiencies, which impair Cbl-dependent remethylation. Acquired and inborn Cbl-related disorders and MTHFR deficiency cause multisystem, often severe disease. Failure to thrive, neurocognitive or psychiatric symptoms, eye disease, bone marrow alterations, microangiopathy and thromboembolic events are characteristic. The recently identified MTHFD1 defect additionally presents with severe immune deficiency. Deficient Cbl-dependent enzymes cause reduced methylation capacity and metabolite toxicity. Further net-effects of perturbed Cbl function or reduced Cbl supply causing oxidative stress, altered cytokine regulation or immune functions are discussed.
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Affiliation(s)
- Martina Huemer
- Division of Metabolism and Children's Research Center, University Children's Hospital Zürich, Zürich, Switzerland
- Department of Paediatrics, Landeskrankenhaus Bregenz, Bregenz, Austria
| | - Matthias R Baumgartner
- Division of Metabolism and Children's Research Center, University Children's Hospital Zürich, Zürich, Switzerland
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Kook PH, Hersberger M. Daily oral cyanocobalamin supplementation in Beagles with hereditary cobalamin malabsorption (Imerslund-Gräsbeck syndrome) maintains normal clinical and cellular cobalamin status. J Vet Intern Med 2018; 33:751-757. [PMID: 30554416 PMCID: PMC6430909 DOI: 10.1111/jvim.15380] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/27/2018] [Accepted: 11/13/2018] [Indexed: 12/25/2022] Open
Abstract
Background Efficacy of PO cobalamin (Cbl) supplementation in dogs with hereditary Cbl malabsorption (Imerslund‐Gräsbeck syndrome, IGS) is unknown. Objectives To evaluate PO Cbl supplementation in Beagles with IGS previously treated parenterally. We hypothesized that 1 mg cyano‐Cbl daily PO would maintain clinical and metabolic remission. Animals Three client‐owned Beagles with IGS and 48 healthy control dogs. Methods Prospective study. Daily PO cyanocobalamin (cyano‐Cbl; 1 mg) supplementation was monitored for 13 (2 dogs) and 8 months (1 dog). Health status was assessed by owner observations. Methylmalonic acid (MMA)‐to‐creatinine concentrations were measured using an ultra‐performance liquid chromatography‐tandem mass spectrometry (UPLC‐TMS) method on urine samples collected monthly. Concurrent measurements of serum MMA concentration (n = 7; UPLC‐TMS) were available for 1 dog. Results All dogs remained in excellent health during PO supplementation. Urine MMA remained consistently low in 2 dogs (median, 2.5 mmol/mol creatinine; range, 1.2‐9; healthy dogs [n = 30], median, 2.9 mmol/mol creatinine; range, 1.3‐76.5). Urine MMA ranged from 38.9‐84.9 mmol/mol creatinine during the first 6 months in 1 dog already known to excrete comparable amounts when supplemented parenterally. Brief antibiotic treatment for an unrelated condition after 6 months resulted in low urine MMA (median, 2.8 mmol/mol creatinine; range, 1.9‐4.8) for the next 7 months. All concurrent serum MMA concentrations (median, 651 nmol/L; range, 399‐919) before and after month 6 were within the established reference interval (393‐1476 nmol/L; n = 48). Conclusions and Clinical Importance One milligram of cyano‐Cbl daily PO appears efficacious for maintaining normal clinical status and normal cellular markers of Cbl metabolism in Beagles with IGS.
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Affiliation(s)
- Peter H Kook
- Clinic for Small Animal Internal Medicine, Vetsuisse Faculty, University of Zurich, Zurich, Switzerland
| | - Martin Hersberger
- Department of Clinical Chemistry, University Children's Hospital Zurich, Zurich, Switzerland
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12
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Kook PH, Reusch CE, Hersberger M. Prospective long-term evaluation of parenteral hydroxocobalamin supplementation in juvenile beagles with selective intestinal cobalamin malabsorption (Imerslund-Gräsbeck syndrome). J Vet Intern Med 2018; 32:1033-1040. [PMID: 29572946 PMCID: PMC5980559 DOI: 10.1111/jvim.15090] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/23/2017] [Revised: 01/24/2018] [Accepted: 01/31/2018] [Indexed: 11/29/2022] Open
Abstract
BACKGROUND Prospective studies on maintenance treatment for Beagles with hereditary selective cobalamin (Cbl) malabsorption (Imerslund-Gräsbeck syndrome, IGS) are lacking. In our experience, measurement of methylmalonic acid (MMA), a Cbl-dependent metabolite, seems more helpful to monitor Cbl status as compared with serum Cbl concentrations. OBJECTIVES To evaluate a standardized Cbl supplementation scheme in Beagles with IGS. We hypothesized that a single parenteral dose of 1 mg hydroxocobalamin (OH-Cbl) would maintain clinical and metabolic remission for up to 2 months. ANIMALS Six client-owned juvenile Beagles with genetically confirmed IGS and 28 healthy control dogs. METHODS Prospective study. Monthly IM OH-Cbl (1 mg) supplementation was done over a median of 9 months (range, 6-13) in 6 dogs, followed by bimonthly (every 2 months) injections in 5 dogs over a median of 6 months (range, 3-10). Health status was assessed by routine clinical examinations at injection time points and owner observations. Voided urine samples were collected immediately before OH-Cbl injections for measurement of MMA-to-creatinine concentrations using a gas-liquid chromatography-tandem mass spectrometry (GC-MS) method. RESULTS All dogs were clinically healthy while receiving monthly and bimonthly OH-Cbl supplementation. Urinary MMA results in healthy dogs ranged from 1.3 to 76.5 mmol/mol creatinine (median, 2.9). Median urinary MMA concentrations did not differ between dogs with IGS receiving monthly (n = 49; 5.3 mmol/mol creatinine; range, 2.3-50.4) and bimonthly (n = 31; 5.3 mmol/mol creatinine; range, 1.6-50) injections. CONCLUSIONS AND CLINICAL IMPORTANCE A maintenance parenteral dose of 1 mg OH-Cbl monthly or bimonthly appears adequate in Beagles with IGS monitored by metabolic testing.
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Affiliation(s)
- Peter Hendrik Kook
- Department for Small Animals, Clinic for Small Animal Internal Medicine, Vetsuisse Faculty, University of Zurich, Winterthurerstrasse 260, Zurich, Switzerland
| | - C E Reusch
- Department for Small Animals, Clinic for Small Animal Internal Medicine, Vetsuisse Faculty, University of Zurich, Winterthurerstrasse 260, Zurich, Switzerland
| | - M Hersberger
- Department of Clinical Chemistry, University Children's Hospital Zurich, Zurich, Switzerland
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Biochemical and Hematologic Manifestations of Gastric Intrinsic Factor (GIF) Deficiency: A Treatable Cause of B12 Deficiency in the Old Order Mennonite Population of Southwestern Ontario. JIMD Rep 2014; 18:69-77. [PMID: 25308559 DOI: 10.1007/8904_2014_351] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/11/2014] [Revised: 07/29/2014] [Accepted: 08/05/2014] [Indexed: 02/25/2023] Open
Abstract
Intrinsic factor deficiency (OMIM #261000, IFD) is a rare inherited disorder of vitamin B12 metabolism due to mutations in the gastric intrinsic factor (GIF) gene.We report three individuals from an Old Order Mennonite community who presented with B12 deficiency. Two cases are siblings born to consanguineous parents and the third case is not known to be closely related. The older male sib presented at 4 years with gastrointestinal symptoms, listlessness, and pallor. He had pancytopenia with megaloblastic anemia. Serum B12 was 61 (198-615 pmol/L). Methylmalonic aciduria was present. C3 was elevated on acylcarnitine profile. Homocysteine was high at 16.7 (5.0-12.0 umol/L). His asymptomatic female sibling was also found to have B12 deficiency. Genetic testing for methylmalonic aciduria (MMAA), transcobalamin deficiency (TCN2), and Imerslund-Gräsbeck syndrome (AMN) showed no mutation in both siblings. The third patient, a 34-year-old woman, had presented in infancy with a diagnosis of pernicious anemia. Mutation analysis of GIF revealed compound heterozygosity for a c.79+1G>A substitution and a c.973delG deletion in all three individuals. Oral or parenteral vitamin B12 has led to complete recovery of clinical parameters and vitamin B12 levels. Newborn screening samples on the siblings revealed normal methylcitrate, C3, and C3/C2 ratios thus indicating no disruption of propionic or methylmalonic acid metabolism.A high index of suspicion should be maintained if children present with megaloblastic anemia since GIF deficiency is a treatable disorder and newborn screening may not be able to detect this condition.
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