Glycogen Storage Disease Clinicopathological Analysis

BackgroundGlycogen storge disease(GSD) is a group of inherited metabolic disorders of glycogen metabolism.TypeⅡ,Ⅲ,ⅤandⅦmainly affect skeletal muscles.In contrast to the development abroad,reports about GSD in our country are infrequent.Specific histochemical method for respective demonstration of phosphorylase,phosphofructokinase and muscle adenylate deaminase deficiency is available,which can be used as a diagnostic tool,but it has not been reported in our country up to now.ObjectivesTo summarize clinical and pathological features of GSD and non-GSD with glycogen accumulation and to analyze the relationship between clinical and pathological manifestation.Methods1.A retrospective study included 15cases GSDⅡand 12 cases GSDⅢgenerated in PUMCH's neuro-pathological institution for the past 20 years.2.A retrospective study included 1593 muscle specimens generated between October 2003 and December 2008 in the institution.Patients with clinically and pathologically suspected GSD and those with accumulation of glycogen on muscle biopsy were screened,on which specific histochemical stains of phosphorylase,PFK,MAD were performed.Analyze the relationship between clinical and pathological manifestation.Results1.Of the 15 cases with definite diagnosis of GSD typeⅡ,there were 9 men and 6 women,whose age of onset were from 3 months to 33years old.The course of disease ranged from 0.1 year to 12 years.2 cases were infantile-onset,which mainly presented with hypotonia,muscle weakness and cardiomyopathy insufficiency.13 cases were late-onset,presenting as a slowly progressive myopathy which selectively affected four limbs and respiratory muscles.The common light micrsopic feature of all case of GSD typeⅡwas a vacuolar myopathy.The vacuoles had a high glycogen content and are strongly reactive for acid phosphatase.2.There were 8 men and 4 women in the group of GSD typeⅢ,who were diagnosed from 2 years old to 27 years old;the course of disease ranged from 0.1 year to 25 years.Clinical features were dominated by liver dysfunction,while myopathy was mild.Muscle biopsy showed vacuolar myopathy,mainly subsarcolemmal,which contained PAS-positive material.3.There were 31 cases met the inclusion criteria for stains.Only one case showed no stain on phosphorylase stain,who was a five years old girl.Muscle biopsy performed for hyperCKemia,diagnosis of GSD typeⅤwas confirmed by histochemistry method.There was no vacuolar on muscle biopsy.The other 30 cases including 20 men and 10 women;according to clinical and pathological manifestation,21 cases still suspected of GSD or other metabolic myopathy,2 cases diagnosed as mitochondrial myopathy,and secondary defect in glycolysis for other causes 7cases.Conclusions1.GSD typeⅡ,Ⅲ,Ⅴexhibit clinical heterogeneity,for the features indentified in the muscle pathology,muscle biopsy is of use to make the definite diagnosis of the group of disease.2.Glycogen accumulation may be secondary to other diseases such as mitochondrial myopathy,which may be partially responsible for some clinical presentations.