Clinical and laboratorial study of 19 cases of mucopolysaccharidoses

The mucopolysaccharidoses (MPS) are a heterogeneous group of inborn errors of lysosomal glycosaminoglycan (GAG) metabolism. The importance of this group of disorders among the inborn errors of metabolism led us to report 19 cases. METHOD: We performed clinical, radiological, and biochemical evaluations of the suspected patients, which allowed us to establish a definite diagnosis in 19 cases. RESULTS: Not all patients showed increased GAG levels in urine; enzyme assays should be performed in all cases with strong clinical suspicion. The diagnosis was made on average at the age of 48 months, and the 19 MPS cases, after a full clinical, radiological, and biochemical study, were classified as follows: Hurler -- MPS I (1 case); Hunter -- MPS II (2 cases); Sanfilippo -- MPS III (2 cases); Morquio -- MPS IV (4 cases); Maroteaux-Lamy -- MPS VI (9 cases); and Sly -- MPS VII (1 case). DISCUSSION: The high relative frequency of Maroteaux-Lamy disease contrasts with most reports in the literature and could express a population variability

Clinical and molecular studies in five Brazilian cases of Friedreich ataxia

Friedreich ataxia (FRDA), the most commom autosomal recessive ataxia, is caused in 94 per cent of cases by homozygous expansions of an unstable GAA repeat localised in intron 1 of the X25 gene. We have investigated this mutation in five Brazilian patients: four with typical FRDA findings and one patient with atypical manifestations, who was considered to have some other form of cerebellar ataxia with retained reflexes. The GAA expansion was detected in all these patients. The confirmation of FRDA diagnosis in the atypical case may be pointing out, as in other reports, that clinical spectrum of Friedreich's ataxia is broader than previously recognised and includes cases with intact tendon reflexes.

A useful routine for biochemical detection and diagnosis of mucopolysaccharidoses

As mucopolissacaridoses (MPS) constituem, devido às suas características bioquímicas, genéticas e clínicas, um grupo grande e heterogêneo dentro das doenças lisôssomicas de depósito (LSD), e säo causadas pela deficiência de enzimas específicas que säo responsáveis pela quebra de gicosaminoglicanos (GAGs) em passos diferentes da sua rota de degradaçäo. Sendo as MPS responsáveis por aproximadamente 32 por cento dos erros inatos do metabolismo (EIM) e 54 por cento das LSD identificadas em nosso laboratório (Laboratório Regional dos Erros Inatos do Metabolismo (RLIEM), Serviço de Genética Médica, Hospital de Clínicas de Porto Alegre), que é um centro de referência para o diagnóstico de LSD no Brasil, nós decidimos implantar uma rotina para detecçäo e o diagnóstico diferencial de MPS em pacientes com características clínicas sugestivas deste grupo de doenças.