Hepatic glycogen storage diseases: symptoms, management and associated mutations

Abstract

Glycogen storage diseases (GSD) are rare diseases derived from altered glycogen metabolism. This leads to glycogen storage in different organs such as muscle, kidney, and liver, resulting in a variety of clinical manifestations. GSD with liver involvement are classified into types I, III, IV, VI, and IX, depending on the enzymes affected. They are clinically characterized by hypoglycemia and hepatomegaly as cardinal signs. Their diagnosis is initially based on clinical manifestations and laboratory test results. Nevertheless, diagnostic certainty requires a genetic study that identifies the specific mutation. Multiple mutations have been associated with each GSD. In Chile, since patients often lack the genetic study, the GSD genetic local characteristics are unknown. The treatment is based on dietary restrictions modulated according to the identified mutation. Today, the international consensus indicates that early diagnosis allows better metabolic control and improves the patient´s quality of life and prognosis. In this review, the information on GSD with liver involvement is updated to optimize the diagnosis, treatment, and follow-up of these patients, emphasizing specific nutritional and gastroenterological management.