diagnosis and treatment of mucopolysaccharidoses (mpss)

mucopolysaccharidoses are a group of rare mostly autosomal recessive metabolic and genetic disorders. because of the high rate of consanguinity, they are not uncommon in our population. clinical diagnosis is not difficult for experienced physicians, but it is not enough for treatment and prevention measures in the future pregnancies. so, it is necessary to detect the type of mps by measurement of responsible enzyme activity in the leukocytes and skin fibroblasts. whenever we determined the exact type of the mps and deficient enzyme, we would be able to treat the patients with the different therapeutic options, like bone marrow transplantation, stem cell transplantation, enzyme replacement therapy, or even gene therapy. at present, wild type or normal enzymes for mpss type i, ii, and iii are being produced by recombinant dna technology. results from phase i, ii, and iii extended clinical studies have shown that the enzymes are safe and efficient and alleviate many systemic signs and symptoms of these diseases. there are some difficulties regarding the marketing and high cost of the available enzymes. if public health responsibilities and insurance companies support the families financially there is not any problem to use enzymes in our patients in iran. in the next step we should consider other therapeutic options like stem cell transplantation, or even gene therapy. now our best choice is to do prenatal testing and detect affected fetuses by enzyme assay on fetal cells by amniocentesis or cvs.