SGLT2i therapy was associated with marked clinical improvement in an adult with GSD1b: a case report

Abstract The pathogenic role of intracellular accumulation of 1,5-anhydroglucitol-6-phosphate (1,5AG6P) in neutropenia and neutrophil dysfunction associated with glycogen storage disease type Ib (GSD Ib) has recently been established. Patients with GSD Ib develop severe hypoglycemia after short periods of fasting. (approximately 2–4 h), hepatomegaly, hyperlactatemia, hyperlipidemia, hyperuricemia, failure to thrive, neutropenia/neutrophil dysfunction, and an increased risk of inflammatory bowel disease and autoimmune diseases. The identification of 1,5AG6P accumulation as a key pathogenic mechanism has provided the rationale for the development of novel therapeutic strategies for GSD Ib. These oral agents, originally approved for the treatment of type 2 diabetes mellitus, inhibit the renal reabsorption of both glucose and 1,5-AG. Clinical experience in adult patients with GSD Ib remains limited, and complete clinical remission has only rarely been reported. This report describes the use of maximal-dose empagliflozin in an adult patient with GSD Ib, severe neutropenia, and inflammatory bowel disease, managed in both hospital and home-care settings. Pharmacological treatment was combined with a structured nutritional regimen aimed at maintaining blood glucose levels as close as possible to the physiological range. The patient experienced marked clinical and biochemical improvement without documented adverse effects. Supportive interventions, including nocturnal drip-feeding and respiratory protective devices, were successfully discontinued, allowing the patient to return to a normal daily life.