Perfil osteometabólico em pacientes com Mucopolissacaridose IVA acompanhados no Hospital Universitário Alcides Carneiro.

Abstract

Mucopolysaccharidoses (MPS) are a group of genetic diseases characterized by the deficiency of lysosomal enzymes involved in the degradation of glycosaminoglycans (GAGs), leading to accumulation of these substances in various organs, resulting in a multisystemic disease. Mucopolysaccharidosis type IV A (MPS-IVA) is characterized by the severity of bone involvement, presenting multiple dysostosis, joint hypermobility and severe short stature. Bone development and mineralization are believed to be abnormal, which in addition to immobility, low nutrient intake and vitamin D deficiency result in early low bone mass. In this cross-sectional study were evaluated bone mineral density, bone mineral content and Z score by bone densitometry of the whole body and forearm; markers of bone turnover; calcium intake in treatment-naive patients with enzyme

replacement and bone turnover markers after six months of treatment with alpha- elossulfase. Twenty-one patients were included in the baseline analysis and 16

were evaluated after six months of treatment. Regarding the baseline data, low

bone mass was found in all patients with a mean Z-score of -3.27. Serum C- telopeptide X (CTX), marker of bone resorption, was above the upper limit of

normal in a significant number of patients with a baseline mean of 0.490 ng/mL. Calcium intake was below that recommended for all patients, presenting a mean of 327.79 mg in 24h. The risk factor that was best associated with the severity of low bone mass was patient immobility. The results of the exams after six months of therapy showed a reduction in the mean value of the CTX, with an average value of 0.470 ng/mL. In the evaluation of the osteometabolic profile of patients with MPSIVA, a high prevalence of low bone mass was identified, which was lower in patients who preserved the ability to ambulate. The reduction in the mean value of CTX after the institution of enzymatic replacement indicates a positive effect of treatment on the bone mass of these patients.