'Glycogen Storage Diseases (GSDs) in Indian Children- Establishing an Indian GSD (I-GSD) Registry'

* Primary objective: * To describe the clinical presentation and outcome of genetically defined cases of pediatric hepatic glycogen storage diseases (GSD) patients. * Study population: Genetically confirmed cases of hepatic GSDs will be enrolled from all the participating centres. * Study design: Multicentric retrospective study (with concomitant long term prospective data collection) * Study period: The study will be an ongoing effort with aim to continuosly expand the participation. Retrospective data collection (of previous data), analysis and drafting of manuscript would be completed between May 2024 to April 2025. New centers willing to join the consortium will be asked to submit their data as on the date of joining. Retrospective follow up data may be asked from the participating centres every every 6 months-1 year. Also, we would continue prospective data collection of newer GSD patients at the collaborating centres.