Purulent discharge from the umbilicus of a 48-year-old man

Abstract

A 48-year-old man presented to the dermatology clinic with a 1-week history of moist erythema with local tenderness over the umbilical region (Fig. 1). The patient had experienced three episodes of omphalitis in the past 10 years but each time the symptoms subsided spontaneously within a few days.At the clinic, he was treated for impetigo using oral amoxicillin and topical mupirocin ointment. Two days later, the patientÕs status quickly deteriorated with diffuse abdominal pain and fever, and he had a foulsmelling discharge from the umbilicus. Muscle guarding focused at the lower abdomen was also noted.Ultrasonography revealed an ovoid hypoechoic mass containing variable echogenic foci under the umbilical area, which suggested abscess formation. Abdominal computed tomography (CT) revealed a lobulated, cystic lesion, 23 · 20 mm in size, surrounded by a thickened lower abdominal wall (Fig. 2) beneath the rectus abdominis muscle, with a connection to the umbilicus. Treatment with intravenous cefazolin and clindamycin was given for coverage against Gram-positive and Gramnegative organisms. Pus culture of the foul-smelling umbilical discharge revealed Bacteroides and Prevotella species. Despite adequate antibiotic coverage, the patientÕs clinical condition continued to deteriorate after admission, and surgical intervention was indicated. The surgical specimen revealed a firm, round, white subcutaneous nodule, 30 · 30 mm in size, connected to the umbilicus. Histopathological findingsExamination of haematoxylin and eosin-stained sections of the excised specimen showed a sinus tract lined by squamous and transitional epithelium with acute suppurative inflammation and an intense foreign-body giant-cell reaction (Figs 3 and 4). Figure 1 Moist erythema, discharge and tenderness in umbilical region.Figure 2 Computed tomography scan of abdomen showing cystic lesion (arrow) surrounded by a thickened lower abdominal wall beneath the rectus abdominis muscle.