Abstract:

Objective: To summarize the clinical, liver biopsy and gene mutation features of glycogen storage disease type Ⅵ and Ⅸa, so as to improve the clinical understanding of the disease. Methods: A retrospective analysis was performed on seven cases' （3 cases of type Ⅵ , 4 cases of type Ⅸa）clinical manifestation, laboratory examination, liver biopsy and gene mutation spectrum. Related literatures of GSDⅥ and Ⅸa were reviewed and the clinical, liver biopsy and genetic features were summarized..Results: ①All the 7 cases were male and diagnosis age was 2 years 3 months to 5 years. There were 7 cases with hepatomegaly and transaminase elevation, 1 case with short stature, 2 cases with fasting hypoglycemia, 2 cases wtih hypertriglyceridemia and hypertriglyceridemia, 3 cases with blood ketone bodies, 2 cases with positive analysis of urine organic acids; 7 patients'liver biopsy revealed diffuse enlargement of hepatocytes with glycogen aggregation, 4 cases with hepatic steatosis; cirrhosis with portal fibrosis was presented in 3 cases of GSD Ⅵ. 6 PYGL mutations were detected in 3 patients of type Ⅵ, c.772+1G>A, c.244-1G>A, c.730C>T(p.L244F), c.2417_2418delTA （p.I806SfsX9）were novel, 4 PHKA2 mutations were detected in 4 patients of type Ⅸa, c.3529C>T(p.Q1177X), c.3574C>T(p.Q1196X) were novel. ②13 literatures were retrieved, together with the 7 cases in this study, there were 22 cases of GSD Ⅵ and 99 cases of GSDⅨa. Almost all the children had hepatomegaly and transaminase elevation, some patients had short stature, fasting hypoglycemia, hypertriglyceridemia, hypertriglyceridemia and blood ketone bodies. All the patients' liver biopsy revealed glycogen aggregation in hepatocytes , 17% showed hepatic steatosis, liver cirrhosis was presented in 25% of type Ⅵ and 33% of type Ⅸa patients. 19 PYGL gene mutations were reported, most were point mutations, splice site mutation was common and insertion mutation was rare. 43 PHKA2 gene mutations were reported and the types were variant.Conclusion: The patients with hepatomegaly accompanied by elevated transaminase should be alerted to be with glycogen storage disease type Ⅵ or Ⅸa; patients with type Ⅵ may have cirrhosis early and require to be further followed-up.