title: Merosin-deficient congenital muscular dystrophy with mental retardation and cerebellar cysts, unlinked to the LAMA2, FCMD, MEB and CMD1B loci, in three Tunisian patients.
abstract: We report three Tunisian patients affected by congenital muscular dystrophy with mental retardation and cerebellar cysts on cranial magnetic resonance imaging. The clinical features were characterized by hypotonia at birth, joint contractures associated with severe psychomotor retardation, absence of speech, inability to walk in three patients, but calf hypertrophy was noted only in two patients. Brain magnetic resonance imaging showed several cerebellar cysts and vermis hypoplasia in all of the patients. Abnormality of the white matter was present in two patients. The pattern of gyration was normal in all cases. Serum creatine kinase was elevated in all three cases and their muscle biopsy showed dystrophic changes compatible with congenital muscular dystrophy. The immunohistochemical analysis of the skeletal muscle revealed partial merosin deficiency, more pronounced for the N-terminal antibody. Linkage analysis excluded congenital muscular dystrophy loci on chromosomes 6q22, 9q31, 1p32 and 1q42. These patients constituted a particular form of congenital muscular dystrophy with a combination of severe motor delay, mental retardation, partial merosin deficiency and cerebellar cysts. Two patients showed white matter abnormalities on magnetic resonance imaging and hypertrophy of the calves. These cases, in addition to those reported previously, confirmed the large phenotypic variability in the group of secondary merosin deficiency congenital muscular dystrophy.
authors.affiliation: Department of Neurology, CHU. HabibBourguiba, 3029, Sfax, Tunisia. chahnez@gnet.tn
authors.forename: Chahnez
authors.initials: C
authors.lastname: Triki
authors.forename: Nacim
authors.initials: N
authors.lastname: Louhichi
authors.forename: Mériam
authors.initials: M
authors.lastname: Méziou
authors.forename: Fakher
authors.initials: F
authors.lastname: Choyakh
authors.forename: Mohamed Salah
authors.initials: MS
authors.lastname: Kéchaou
authors.forename: Rachid
authors.initials: R
authors.lastname: Jlidi
authors.forename: Chokri
authors.initials: C
authors.lastname: Mhiri
authors.forename: Faiza
authors.initials: F
authors.lastname: Fakhfakh
authors.forename: Hamadi
authors.initials: H
authors.lastname: Ayadi
mesh_terms: D001921:Brain / Q000473:pathology; D020863:Central Nervous System Cysts / Q000209:etiology* / Q000473:pathology; D002648:Child; D002675:Child, Preschool; D002874:Chromosome Mapping; D005260:Female; D005455:Fluorescent Antibody Technique; D008040:Genetic Linkage / Q000235:genetics; D005819:Genetic Markers; D006801:Humans; D008607:Intellectual Disability / Q000209:etiology* / Q000235:genetics; D007797:Laminin / Q000172:deficiency* / Q000378:metabolism; D008126:Lod Score; D008279:Magnetic Resonance Imaging; D008297:Male; D008565:Membrane Proteins; D018482:Muscle, Skeletal / Q000378:metabolism; D009136:Muscular Dystrophies / Q000150:complications / Q000151:congenital / Q000235:genetics*; D010375:Pedigree; D011506:Proteins / Q000235:genetics*; D014416:Tunisia
chemical_list: C113587:FKTN protein, human; D005819:Genetic Markers; D007797:Laminin; D008565:Membrane Proteins; D011506:Proteins; C102645:laminin alpha 2