A retrospective study on sleep-disordered breathing in Morquio-A syndrome

Respiratory problems are common in Morquio-A syndrome (MPS IVA) but objective data on sleep-disordered breathing are scarce. The aim of our study was to review polygraphic (PG) findings and the need for noninvasive continuous positive airway pressure (CPAP) or noninvasive ventilation (NIV) in children with MPS IVA. A retrospective review of the clinical charts and PG of 16 consecutive children (7 boys, mean age 10.5 ± 4.2 years) with MPS IVA seen over a period of 3 years was performed. The prevalence of obstructive sleep apnea (OSA) was 69% with only five patients, all younger than 10 years old, having a normal PG. Four patients had mild OSA (apnea-hypopnea index [AHI] ≥1.5 and <5 events/hr), three patients had moderate OSA (AHI ≥5 and <10 events/hr), and three patients had severe OSA (AHI ≥ 10 events/hr). Among the 10 patients with OSA, 3 had prior adenoidectomy ± tonsillectomy and 6 were on enzyme replacement therapy. Only one patient had a central apnea index >5 events/hr despite prior cervico-occipital decompression. Six patients, all older than 11 years old, were started on CPAP or NIV because of severe OSA (n = 4), nocturnal hypoventilation (n = 1), or impossibility to be weaned from NIV after an acute respiratory failure (n = 1). Prevalence of OSA is high in patients with MPS IVA, underlying the importance of a systematic screening for sleep-disordered breathing. CPAP and NIV are efficient and well accepted for treating sleep-disordered breathing.