Résumé
Mucopolysaccharidoses [MPS] are chronic progressive lysosomal disorders [Six distinct types] which are inherited as autosomal recessive except MPS II which is inherited as X-linked recessive disorder This study is designed to investigate a group of Egyptian patients with MPS biochemically using screening test by electrophoretic separation of glycosaminoglycans and enzymatic assay in order to establish the diagnosis of the disorder and its subtypes, to prepare patients for enzyme replacement therapy. Also this will help in proper genetic counseling and prenatal diagnosis. Establishing a reliable rapid screening test for MPS is another aim of the study. The present study included 20 index cases suspected clinically as mucopolysaccardioses at the Medical Genetics Center, Ain Shams University [ASUMGC].They were subjected to full history taking, thorough clinical examination, family pedigree construction, skeletal survey, abdominal ultrasound and echocardiography, quatitative assay of glycosaminoglycans [GAGs] by diemethylmethlene blue [DMB] is done. The level of urinary GAGs by two dimentional electrophoresis [DMB] test was high in all patients tested. After that the patients were subjected to 2-DEP to determine the pattern of GAGs for probable type of MPS. 11 cases [55%] showed big dermatan sulfate spot [Type I, II or VI]. Seven cases [35%] showed hepran sulfate spot [Type III], 2 cases [10%] showed keratan sulfate spot [Type IV]. Finally patients were subjected to enzyme analysis specific for each type of MPS to confirm diagnosis. Reaching a specific diagnosis is of importance for genetic counseling and prenatal diognosis which is possible for all types of MPS. Prenatal diagnosis was done by 2-DEP of the amniotic fluid for four mothers of affected patients of MPS. One fetus was proved to be affected with MPS III. Another fetus was affected with MPSII. The others fetuses were normal