Overcoming the barriers to diagnosis of Morquio A syndrome

Abstract

BackgroundMorquio A syndrome is an autosomal recessive lysosomal storage disease often resulting in life-threatening complications. Early recognition and proficient diagnosis is imperative to facilitate prompt treatment and prevention of clinical complications.MethodsExperts in Asia Pacific reviewed medical records focusing on presenting signs and symptoms leading to a diagnosis of Morquio A syndrome.ResultsEighteen patients (77% female) had a mean (median; min, max) age of 77.1 (42.0; 0.0, 540.0) months at symptom onset, 78.9 (42.0; 4.5, 540.0) months at presentation and 113.8 (60.0; 7.0, 540.0) months at diagnosis. Orthopedic surgeons and pediatricians were most frequently consulted pre-diagnosis while clinical geneticists/metabolic specialists most frequently made the diagnosis. Delayed diagnoses were due to atypical symptoms for 5 patients (28%), while 4 patients (22%) experienced each of subtle symptoms, symptoms commonly associated with other diseases, or false-negative urine glycosaminoglycan analysis. Two patients (11%) each experienced overgrowth within the first year of life. Two patients with Morquio A syndrome (11%) were diagnosed with craniosynostosis and 1 (6%) for each of Legg-Calvé-Perthes disease, Leri-Weill syndrome, and pseudoachondroplasia. Early radiographic features of Morquio A syndrome led to more efficient diagnosis.ConclusionsIncreased awareness of clinical symptomology overlapping with Morquio A syndrome is essential. Clinicians encountering patients with certain skeletal dysplasia should consider Morquio A syndrome in their differential diagnosis. Atypical or subtle symptoms should not eliminate Morquio A syndrome from the differential diagnosis, especially for patients who may have non-classical phenotype of Morquio A syndrome.

Diagnosis of Morquio-A patients in Mexico: How far are we from prompt diagnosis?

“…Generally, before definitive diagnosis, patients are delayed or misdiagnosed due the lack of knowledge about the disease (10,11).…”

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

“…Patients with MPS IVA usually have corneal clouding, but corneal opacity may be subtle or even absent 12. In contrast to the joint stiffness that is observed in other MPS subtypes, the joints in MPS IVA are typically hypermobile secondary to ligamentous laxity 13. Although patients with MPS IVA have a normal birth length, growth velocity usually decreases between 1 and 3 years of age, with an average height of 123 cm at 18 years of age compared with 177 cm in unaffected males 14.…”

Evaluation of Demographic and Clinical Characteristics of Patients with Mucopolysaccharidosis

“…Similar to ours, several studies from different countries showed that the diagnosis was established on average 2-3 years after the onset of symptoms (20,(25)(26)(27)(28)(29). In a case of MPS, since patients exhibit different organ/system manifestations, they present to physicians from different branches including pediatricians, geneticists, cardiologists, ophthalmologists, orthopedists, and neurosurgery, and are diagnosed with different disorders such as primary valvular heart disease, Perthes disease, congenital talipes equinovarus, spondyloepiphyseal dysplasia, cataract, rheumatoid arthritis, craniosynostosis, pseudoachondroplasia, and inguinal hernia (23,27,29,30). In a study, patients were detected to be evaluated by 5 physicians on average before the diagnosis was made (29).…”