CLINICAL-MOLECULAR CORRELATION IN 104 MILD X-LINKED MUSCULAR-DYSTROPHY PATIENTS - CHARACTERIZATION OF SUBCLINICAL PHENOTYPES

A multidisciplinary study was conducted in order to assess dystrophin expression in a large series of mild X-linked muscular dystrophy patie nts, with well-defined clinical phenotype. Patients (104) were divided in 4 clinical groups, according to clinical severity: asymptomatic (s ub-clinical), benign, moderate and severe, Cardiopathy was also assess ed, and dilated cardiomyopathy was found in 47% of sub-clinical and be nign cases. Myoglobinuria, cramps and myalgia were also associated wit h a sub-clinical or benign clinical status. Dystrophin immunohistochem ical pattern of labelling and dystrophin amount decreased gradually ac ross clinical groups. Our study showed a significative correlation bet ween: (1) dystrophin amount and immunohistochemical score(p < 0.05); ( 2) dystrophin amount and clinical score(p < 0.05). Therefore, the comb ined use of these different techniques for prognosis of mild X-linked muscular dystrophy patients is useful. Our study assesses the prevalen ce of the various disease courses in a large cohort of mild X-linked m uscular dystrophy patients. From our series, up to 30% of patients may be either asymptomatic or have sub-clinical changes.