The continuous dribble of clear acid fluid from an umbilical fistula is not necessarily pathognomonic of a patent urachus. An 8 1/2-month-old child was referred because of an intensely inflamed umbilicus from which clear fluid had dribbled constantly since birth. The history was otherwise noncontributory. Physical examination revealed that the child was normal except for the region of the umbilicus. This was intensely inflamed with a surrounding area of cellulitis. It was covered with a purulent exudate and from the center one observed the slow, constant flow of clear fluid which gave a strongly acid reaction with sodium dinitrophenylazo-napthol disulfonate (Nitrazine) paper. The flow of fluid was carefully observed and aspirated with a pipet as it appeared. The volume measured about 0.5 cc. every 10 minutes.
The tentative diagnosis of a patent urachal duct was made. The patient was placed on penicillin therapy and local hot-wet dressings were applied locally for
Newman SR, Landes RR, Eggleston RB. DRIBBLING FROM AN UMBILICAL FISTULA. JAMA. 1960;172(5):448-449. doi:10.1001/jama.1960.63020050001011