urachal sinus ICD10:Q64.4 MONDO:0018552 Orphanet:431344 SCTID:451030007 UMLS:CN237553 Urachal sinus is a type of congenital urachal anomaly resulting from the failure of the umbilical end of the urachus to close, without continuity to the bladder, and that is usually asymptomatic but can present with continuous cloudy umbilical discharge, tender midline infraumbilical mass and fever when infected. congenital urachal anomaly