A 55-year-old obese white American woman of European descent presented with a 4-month history of slightly hemorrhagic discharge from her umbilicus. There was no history of fever, abdominal pain or any other systemic disease. Physical examination revealed a deep umbilicus with a barely visible opening. There was no redness, edema, or crusting of the periumbilical skin. The deeper aspect of the umbilicus was exposed by using a spatula. A dark, rounded polypoid mass was noted. The clinical impression was that of fibro-epithelial polyp or some other tumor. An attempt was made to remove the mass by excising the base; however, the mass easily came out of the umbilical cavity implying that either it was necrotic or it was not firmly attached to the umbilical tissue at the base. The gray-tan 0.8 cm size round mass on cut section revealed white fibrous appearance. On microscopic examination, it was composed of lint material with typical morphology of refractile bean-shaped and elongated colorless structures, red spindle-shaped keratin material, granular red debris, rare hair fragments and polymorphonuclear leukocytes (Figure 1). Under polarized light, the lint particles showed brilliant blue-green birefringence (Figure 2). A diagnosis of ‘lint ball’ omphalitis was made.

Umbilical discharge in adult is rare but can be quite alarming. It may be caused by various congenital or acquired conditions. Patients with embryonal anomalies, such as patent urachus, urachal cyst or sinus, patent vitelline duct, vitelline cyst or sinus may present as umbilical discharge [1]. However, the most common cause of umbilical discharge in adult is acquired conditions, such as pilonidal sinus disease [2,3], infection due to hair tufts and foreign bodies [4], and non-specific acute and chronic inflammation and abscess of the umbilicus [5]. Very rare causes include endometriosis and metastatic carcinoma [4].