Mutation in PHKA2 leading to childhood glycogen storage disease type IXa: A case report and literature review

INTRODUCTION: Glycogen storage disease (GSD) type IX, characterized by liver enlargement and elevated aminotransferase levels, is the most frequent type of GSD. The global incidence of GSD type IXa is only about 1/100,000 individuals. Case reports of GSD type IX are rare in China. We present the first case report of GSD type IXa in Northeast China caused by mutation of PHKA2. PATIENT CONCERNS: An 11-year-old boy was referred to our hospital because of liver enlargement with consistently elevated transaminase levels over 6 months. DIAGNOSIS: Histopathological results following an ultrasound-guided liver biopsy confirmed a diagnosis of GSD. Further genetic testing showed that the patient had GSD type IXa caused by the c.133C>T mutation in PHAK2. INTERVENTIONS: We placed the patient on a high-protein and high-starch diet and provided hepatoprotective and supportive therapy. OUTCOMES: The patient's transaminase levels decreased significantly and were nearly normal at 10-month follow-up. CONCLUSION: This is the first reported case of GSD type IXa in Northeast China. We hope that the detailed and complete report of this case will provide a reference for the diagnosis of liver enlargement of unknown etiology in future clinical practice.