Prenatal genetic testing, counseling and follow-up of 33 Egyptian pregnant females with history of mucopolysaccharidoses

ABSTRACT

Mucopolysaccharidoses [MPS] are autosomal recessive disorders characterized by deficiency of lysosomal enzymes which break down the glycosaminoglycans [GAGs] which results in widespread intra and extra-cellular accumulations of GAGs. Early initiation of treatment, before the onset of irreversible tissue damage, clearly provides a favorable disease outcome. Early detection might be afforded by analysis of amniotic fluid. To report our experience of prenatal diagnosis of MPS over 14-year period for cases referred from medical centers throughout Egypt. Also to report the benefit of prenatal genetic testing in cases accompanied with genetic disorders. The present study included 33 pregnant women at risk of having a fetus with MPS. Of these cases, 3 women had more than one pregnancy evaluated. All cases had a detailed genetic ultrasound examination and a maternal serum alpha-fetoprotein [MSAFP] evaluation during the second trimester of pregnancy. Thirty-eight amniocentesis procedures were performed during the study for 2 dimensional electrophoresis [2-DEP] of GAGs. Positive consanguinity was present in near 70% [23/33] of the couples. Detailed genetic ultrasound examination revealed a case with anencephaly and another one with a twin pregnancy One case had a MSAFP of 3.6 multiple of the normal median [open neural tube defect]. Another 2 cases had a risk of having Down syndrome. Results of the 2-DEP of GAGs in amniotic fluid revealed 36.8% [14/33] affected fetuses. During the final counseling setting of the 14 cases with abnormal results, 43% [6/14] elected to continue their pregnancy while 57% [8/14] elected termination. Early prenatal screening and diagnosis, through a systematic multidisciplinary approach, to all cases of mucopolysaccharidoses are recommended, to improve the quality of life and to avoid the presence of other associated fetal developmental malformations