Metastatic abscess formation in a preexisting chest wall tumor: a rare initial presentation of Klebsiella pneumoniae liver abscess.

The common infectious agents in the chest wall include Mycobacterium tuberculosis, Actinomyces, fungi, Nocardia, Entamoeba histolytica, and other aerobes and anaerobes. Klebsiella pneumoniae is an uncommon etiological agent. We describe a case of ankylosing spondylitis in a 45-year-old man, who had exhibited a painless lump in the left posterior chest wall for 3 months and who presented with acute-onset pain, erythematous change, and fever in the 2 weeks before admission. Cultures of the blood and chest wall abscess both showed Gram-negative bacilli, which were classified as K. pneumoniae. A contrast-enhanced computed tomography scan of the abdomen revealed a nonenhancing cystic abscess measuring 4.9 × 6.5 × 6.4 cm in segment 6 of the liver and communicating with the chest wall. Drainage of the liver abscess under ultrasound guidance and open surgical drainage of the chest wall abscess combined with adequate antibiotic treatment resolved the abscess.