Chylothorax in Down's syndrome associated with hydrops fetalis.

Hydrops fetalis is an unusual manifestation of Down's syndrome and diagnosis of Down's syndrome in the hydropic newborn can be difficult as the clinical signs are masked by severe oedema. The baby may also be seriously ill and die soon after birth, before any investigative procedures could be done. Down's syndrome should be considered in foetuses or babies presented with pleural effusion and/or ascites.