1. Cytosolic phosphoenolpyruvate carboxykinase deficiency : Expanding the clinical phenotype and novel laboratory findings
- Author
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Tuula Arkkola, Matti Nuutinen, Maria K Haanpää, Marja-Leena Väisänen, Päivi J. Miettinen, Katariina Latva, Päivi Myllynen, Riikka Keski-Filppula, Kari Kaunisto, Virpi Sidoroff, Pekka Valmari, Johanna Uusimaa, Elisa Rahikkala, Irina I Nagy, Marja Ojaniemi, Päivi Vieira, HYKS erva, Päijät-Häme Welfare Consortium, Centre of Excellence in Stem Cell Metabolism, HUS Children and Adolescents, Clinicum, Timo Pyry Juhani Otonkoski / Principal Investigator, and Children's Hospital
- Subjects
Adult ,pediatrics ,seizure ,CHILDHOOD ,Physiology ,Ketone Bodies ,Hypoglycemia ,Compound heterozygosity ,HEPATIC GLUCONEOGENESIS ,HYPOGLYCEMIA ,PCK1 ,Ketogenesis ,Genetics ,medicine ,Humans ,Hypoglycemic Agents ,Child ,Genetics (clinical) ,business.industry ,pck1 ,Neonatal hypoglycemia ,Liver Diseases ,1184 Genetics, developmental biology, physiology ,PROFILES ,medicine.disease ,Phenotype ,gluconeogenesis ,3121 General medicine, internal medicine and other clinical medicine ,Ketone bodies ,Phosphoenolpyruvate Carboxykinase (GTP) ,citric acid cycle ,business ,Phosphoenolpyruvate carboxykinase ,Urine organic acids ,Carbohydrate Metabolism, Inborn Errors - Abstract
Cytosolic phosphoenolpyruvate carboxykinase (PEPCK-C) deficiency due to the homozygous PCK1 variant has recently been associated with childhood-onset hypoglycemia with a recognizable pattern of abnormal urine organic acids. In this study 21 children and three adult patients with genetically confirmed PEPCK-C deficiency were diagnosed during the years 2016-2019 and the available biochemical and clinical data were collected. All patients were ethnic Finns. Most patients (22 out of 24) had a previously published homozygous PCK1 variant c.925G>A. Two patients had a novel compound heterozygous PCK1 variant c.925G>A and c.716C>T. The laboratory results showed abnormal urine organic acid profile with increased tricarboxylic acid cycle intermediates and inadequate ketone body production during hypoglycemia. The hypoglycemic episodes manifested predominantly in the morning. Infections, fasting or poor food intake, heavy exercise, alcohol consumption and breastfeeding were identified as triggering factors. Five patients presented with neonatal hypoglycemia. Hypoglycemic seizures occurred in half of the patients (12 out of 24). The first hypoglycemic episode often occurred at the age of 1-2 years, but it sometimes presented at a later age, and could re-occur during school-age or adulthood. This study adds to the laboratory data on PEPCK-C deficiency, confirming the recognizable urine organic acid pattern and identifying deficient ketogenesis as a novel laboratory finding. The phenotype is expanded suggesting that the risk of hypoglycemia may continue into adulthood if predisposing factors are present. This article is protected by copyright. All rights reserved.
- Published
- 2022