Clinical analysis and long-term treatment monitoring of 3 patients with glycogen storage disease type Ib.

Background: To investigate the clinical and genetic characteristics of patients with glycogen storage disease type Ib (GSD Ib).

Case Presentation: This report retrospectively analyzed the clinical data of 3 patients with GSD Ib admitted into our hospital, and summarized their onset characteristics, clinical manifestations, related examinations and treatment as well as mutational spectrum. After gene sequencing, the diagnosis of GSD Ib was confirmed in all 3 patients. Five variants of SLC37A4 gene were detected, of which c. 572C > T was the common variant and c. 680G > A was a novel variant. The 3 cases of GSD Ib were mainly affected by liver enlargement, growth retardation, etc., and all had a history of repeated infections. At the onset, patients mainly manifested as mildly elevated alanine-aminotransferase (ALT), accompanied by decreased absolute neutrophil count (ANC), hypertriglyceridemia, and metabolic disorders (hypoglycemia, hyperlactic acidemia, metabolic acidosis, etc.). After long-term treatment by oral uncooked cornstarch, the abnormal liver enzymes gradually returned to normal, and metabolic abnormalities were basically controlled most of the time. With increasing age, ANC of 2 patients decreased progressively, whereas the times of infections was reduced.

Conclusions: We reported 3 cases with GSD Ib and a novel SLC37A4 variant. The possibility of GSD type Ib should be kept on alert when a patient suffers recurrent infections, accompanied by hepatomegaly, elevated liver enzymes, hypoglycemia, dyslipidemia, and metabolic disorders.