First Case of Liver Abscess in Scandinavia Due to the International Hypervirulent Klebsiella Pneumoniae Clone ST23
An 85-year old Caucasian man was admitted to the hospital with a history of 2-3 weeks of anorexia, fatigue, headache and dyspnoea. The patient had prior to hospitalization taken penicillin per os (p.o.) for seven days for pneumonia without effect. His only medical history was a pacemaker implementation one year previously, due to III degree AV-block. After admission the patient was treated with intravenous (i.v.) G-penicillin and gentamicin on suspicion of pneumonia and endocarditis. Chest X-ray and echocardiography were normal. Unfortunately, blood and urine cultures were taken after institution of antibiotics and showed no growth. Due to poor clinical response antibiotics were changed first to i.v. mecillinam on day 7, and later to i.v. cefuroxime on day 9.\nDue to elevated alkaline phosphatase an abdominal ultrasound and CT were performed on day 14 showing an abscess measuring 10.5 x 7.2 x 8.7cm in the right liver lobe. By ultrasonic guided abscess drainage, 20 cubic cm of pus giving growth to K. pneumoniae was removed. Antibiotics were stopped after two days and the patient was discharged without any further treatment or follow up.\nThe patient was re-admitted to the hospital 109 days later due to collapse at home. On suspicion of urosepsis he was treated with i.v. cefuroxime and later supplemented with gentamicin. Liver ultrasound showed no abscess, but as blood culture showed growth of K. pneumoniae a new CT scanning was performed. The CT scan showed a new liver abscess about 2 cm in diameter, in close relation to the original liver abscess. The original liver abscess area was reduced to about 3 cm in diameter, and was hypodense with possible signs of infections/edema. Ten days after admission antibiotics was changed to ciprofloxacin p.o. for 41 days. After discontinuation of antibiotics, the patient was followed weekly with blood samples, and was after one month declared free from infection, as both CRP and leukocytes had remained normal.\nThe patient had no history of foreign travel and also no contact with people from Southeast Asia. Eighteen months after the last follow up the patient was doing well and had no sign of relapse.\nThe K. pneumoniae blood isolate was hypermucoviscous as shown by the formation of a mucoviscous strings when a loop was passed through a colony. Capsular serotype was K1 and it belonged to ST23 as determined by the K. pneumoniae MLST scheme described by Diancourt et al. []. The isolate was positive for the following virulence factors: aerobactin, allS, kfu and rmpA as revealed by polymerase chain reaction using specific primers [].