Mucopolysaccharidosis type IVA (Morquio A): a close differential diagnosis of spondylo-epiphyseal dysplasia.

Patients with mucopolysaccharidoses (MPS) have a plethora of multisystemic manifestations depending on the particular type, and atypical presentations are not uncommon. MPS type IVA (Morquio A syndrome) has predominant musculoskeletal system involvement and corneal clouding with normal intelligence and can be misdiagnosed as primary skeletal disorders in clinical practice. The absence of corneal clouding with normal urinary glycosaminoglycans (GAGs) level in a proportion of patients with MPS IVA makes the correct diagnosis even more challenging for physicians. Healthcare providers across specialties should have a high degree of suspicion for MPS IVA in all patients with suspected spondylo-epiphyseal dysplasia as early diagnosis and early treatment significantly improve the clinical outcome and activity of daily living.

Activity of daily living for Morquio A syndrome.

The aim of this study was to evaluate the activity of daily living (ADL) and surgical interventions in patients with mucopolysaccharidosis IVA (MPS IVA). The factor(s) that affect ADL are age, clinical phenotypes, surgical interventions, therapeutic effect, and body mass index. The ADL questionnaire comprises three domains: "Movement," "Movement with cognition," and "Cognition." Each domain has four subcategories rated on a 5-point scale based on the level of assistance. The questionnaire was collected from 145 healthy controls and 82 patients with MPS IVA. The patient cohort consisted of 63 severe and 17 attenuated phenotypes (2 were undefined); 4 patients treated with hematopoietic stem cell transplantation (HSCT), 33 patients treated with enzyme replacement therapy (ERT) for more than a year, and 45 untreated patients. MPS IVA patients show a decline in ADL scores after 10years of age. Patients with a severe phenotype have a lower ADL score than healthy control subjects, and lower scores than patients with an attenuated phenotype in domains of "Movement" and "Movement with cognition." Patients, who underwent HSCT and were followed up for over 10years, had higher ADL scores and fewer surgical interventions than untreated patients. ADL scores for ERT patients (2.5years follow-up on average) were similar with the-age-matched controls below 10years of age, but declined in older patients. Surgical frequency was higher for severe phenotypic patients than attenuated ones. Surgical frequency for patients treated with ERT was not decreased compared to untreated patients. In conclusion, we have shown the utility of the proposed ADL questionnaire and frequency of surgical interventions in patients with MPS IVA to evaluate the clinical severity and therapeutic efficacy compared with age-matched controls.

Morquio syndrome: a rehabilitation perspective.

Morquio Syndrome (mucopolysaccharidosis type IV A) is a rare inherited connective tissue disorder characterized by skeletal dysplasia, restrictive pulmonary disease and normal intelligence. Tetraplegia secondary to subluxation of C1 over C2 because of odontoid dysplasia is a common occurrence in these patients but there are limited descriptions regarding their specific physiatric management. Two patients (aged 20 and 17 years) were admitted to a pediatric rehabilitation facility after cervical spine stabilization following recurrent tetraplegia (C4 ASIA C and C4 ASIA D). Following surgery, patients were ventilator dependent and aphonic. One patient was successfully weaned off the ventilator to nocturnal BiPAP, while the other was able to tolerate three hours of ventilator free time despite being ventilator dependent for ten years. At discharge, both patients showed significant improvement in mobility, self care skills and communication abilities. Functional independence was encouraged through use of various assistive devices for mobility, activities of daily living (ADL) and communication. Group counseling and peer support were extremely helpful in their adjustment to disability. Physiatric intervention is essential and requires understanding of the unique impairments encountered by tetraplegics with Morquio Syndrome.