Heterogeneity of classic congenital muscular dystrophy with involvement ofthe central nervous system: Report of five atypical cases

A heterogeneous group of patients with congenital muscular dystrophy associ ated with clinical or radiologic central nervous system involvement other t han the severe classic form with merosin deficiency, muscle-eye-brain disea se, and Walker-Warburg syndrome is described. A probable hereditary or fami lial occurrence could be suggested in all patients. One merosin-positive pa tient presented severe motor incapacity and cerebral atrophy without any cl inical manifestation of central nervous system involvement. A second patien t, also merosin-positive, had moderate motor and mental handicap, and epile psy with no changes in neuroimaging. A third patient, found to have partial merosin deficiency by muscle biopsy manifested severe psychomotor retardat ion and cerebral atrophy with foci of abnormal white-matter signal on magne tic resonance imaging. Finally, two merosin-positive siblings with microcep haly, mental retardation, and an incapacitating progressive neuromuscular c ourse, exhibited cataracts without defects of neuronal migration or brain m alformation. This report emphasizes the broad clinical spectrum and heterog eneity of merosin-positive congenital muscular dystrophy with associated ce ntral nervous system involvement, and illustrates the importance of further studies on clinical, immunohistochemical, and genetic grounds for identify ing new subsets of congenital muscular dystrophy.