Congenital central alveolar sleep-related hypoventilation (Q41284)

Congenital central alveolar hypoventilation syndrome (CCHS) is a disorder of autonomic dysfunction, primarily the failure of automatic central control of breathing, caused by a mutation of the PHOX2B gene. CCHS is characterised by hypoventilation, which is worse during sleep than wakefulness. Onset is usually at birth, and CCHS most commonly presents in an otherwise normal-appearing infant who is noted to have cyanosis, feeding difficulties, hypotonia or, less commonly, central apnoea. Severity is related to the specific mutation present. Individuals with milder variants of the disorder may not present for clinical attention until adulthood. Note: A definitive diagnosis requires demonstration of PHOX2B mutation and objective evidence based on polysomnography with carbon dioxide (CO2) monitoring (by arterial, end-tidal or transcutaneous measures).