Congenital central hypoventilation syndrome and carbon dioxide sensitivity.

[hirschsprung disease]

Congenital central hypoventilation syndrome (CCHS ) is characterised by hypoventilation most marked during sleep and is often associated with abnormalities of the autonomic nervous system . We report an infant with severe CCHS and Hirschsprung disease in whom , while awaiting genotyping , the diagnosis was facilitated by the results of a carbon dioxide (CO 2 ) sensitivity study in the neonatal period and was confirmed by paired-like homeobox 2 B (PHOX 2 B ) mutational analysis . The infant had no ventilatory response to increased inspired carbon dioxide levels when either awake or asleep suggesting he had a severe form for CCHS ; indeed , he subsequently demonstrated to have the 20 /31 genotype . This is the first case report of a genotype-confirmed CCHS disease in a neonate with Hirschsprung disease further characterised by a ventilatory challenge . Conclusion : CO 2 sensitivity status may assist in determining the severity of the CCHS .