ICD-11

Pilonidal disease describes a spectrum of clinical presentations, ranging from asymptomatic hair-containing cysts and sinuses to large symptomatic abscesses of the sacrococcygeal area which tend to recur. It is found predominantly in white males in their second and third decades and is thought to result from penetration of hair into the tissues with the formation of sinuses and a foreign-body granulomatous response. Risk factors for pilonidal disease include male gender, Caucasian ethnicity, sitting occupations, obesity, a deep natal cleft, and presence of hair within the natal cleft.