Long-term follow-up and response to elosulfase alfa in mucopolysaccharidosis type IVA: a single-center cohort from the Czech Republic
摘要
Mucopolysaccharidosis type IVA (MPS IVA, Morquio A syndrome) is a rare lysosomal storage disease primarily characterized by severe skeletal dysplasia. Clinical and laboratory data, including treatment responses, are reported for a cohort of Czech patients with MPS IVA.
ResultsNineteen patients with MPS IVA from 17 families (13 M/6F) were included; only one patient exhibited a mild form. The median age at first symptom onset was 3.0 years (IQR 1.6–3.4), whereas the median age at confirmed diagnosis was 5.0 years (IQR 3.9–5.7). At the time of diagnosis, all patients had skeletal symptoms (pectus carinatum in 58%, short stature in 47%, hip dysplasia in 47%), and 63% had nonskeletal symptoms. Each patient underwent at least one surgical procedure (77% knee, 59% spine, 41% adenotomy). On spinal magnetic resonance imaging, 76% of patients presented with cervical stenosis, and 41% had cervical myelopathy. Eight patients received enzyme replacement therapy for a median duration of 5.5 years (IQR 4.2–6.4). Stabilization or improvement in monitored parameters, including mean forced vital capacity (FVC), forced expiratory volume in 1 s (FEV1), and mean 6-Minute Walk Test distance, were observed in treated patients. Additionally, the hidradenitis suppurativa observed in three patients improved with biologic therapy. We also describe two novel variants (c.421_422dupTG, c.482G > C).
ConclusionsDocumenting the natural history of MPS IVA in this population may aid early diagnosis. Despite the disease’s progressive nature, ERT led to stabilization of monitored parameters in treated children.