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Abstract

Haddad syndrome, defined by the dual presence of congenital central hypoventilation syndrome (CCHS) and Hirschsprung disease (HD), represents a rare neurocristopathy with significant morbidity. Waardenburg syndrome (WS), characterized by pigmentary anomalies, sensorineural deafness, and mutations affecting neural crest derivatives, has not previously been described in combination with Haddad syndrome. We report a unique case of a term male neonate who presented with abdominal distension, aganglionic megacolon, and progressive hypoventilation within 48 hours of life. Distinctive phenotypic features—including a white forelock, hypopigmented skin patches, and vivid blue irides—raised early suspicion of WS. Levelling biopsies confirmed total colonic aganglionosis, while a PHOX2B poly alanine expansion mutation established the diagnosis of CCHS. This dual diagnosis constitutes a previously unreported neurocristopathy overlap. Early phenotype driven recognition, timely surgical decompression, ventilatory support, conservative physiotherapy and long term multidisciplinary care were pivotal to outcome.