Background: Muscular dystrophy usually involves a deficiency in the proximal muscles. We report a case of distal muscular dystrophy in a Moroccan patient.
Case report: A 21-year-old Moroccan complained of progressive onset weakness of the lower limbs and frequent falls. The neurological examination demonstrated amyotrophy involving both legs and almost complete regression of the posterior muscle compartment. Clinical findings were confirmed by muscle scans. The electromyogram showed a progressive myogenic process. Creatine kinase was elevated. The severe dystrophic aspect was evidenced at muscle biopsy and led to the diagnosis of distal Miyoshi muscular dystrophy.
Discussion: Miyoshi muscular dystrophy, a distal myopathy transmitted by autosomal recessive inheritance, is usually observed in young adults who present characteristic amyotrophy of the posterior leg muscles. The proximal muscles of the lower and upper limbs may become involved during the disease course. Approximately one-third of the patients require wheel chair assistance after 10 years. Creatine kinase levels are constantly elevated. The differential diagnosis with other muscular dystrophies predominating in the distal muscles, particularly Steinert's myotonic dystrophy and inclusion body myositis, is discussed.