A mass in the left groin: an infected pseudoaneurysm

A young woman presented to the surgical assessment unit for pain and swelling of the left groin. She reported a two month history of a lump in the left groin that had gradually been increasing in size. She had no other symptoms apart from an intermittent fever ranging between 38.0°C and 39.0°C. She had no medical history or family history of note. On direct questioning she admitted to a previous history of intravenous drug use but denied injecting for many years. No needle marks were noted in the groin. On examination she had pyrexia, at 38.1°C. She had a 3 × 5 cm expansile, pulsatile mass, palpable in the left inguinal region. Blood examination found a raised white cell count at 14 × 10⁹ cells/litre and C reactive protein of 142 mg/l. A colour duplex scan showed an abnormal waveform pattern; subsequent computed tomography was arranged immediately (fig 1⇓).