KLEBSIELLA PNEUMONIAE URINARY TRACT INFECTION CAUSING A PYOGENIC LIVER ABSCESS: A CASE REPORT

Pyogenic liver abscess is a common abdominal infection, with an incidence of 2.3 to 17.59 cases per 100,000 person-years. While Escherichia coli was previously the main causative agent, Klebsiella pneumoniae has become more prevalent in recent decades, especially in Asia. This shift is significant because K. pneumoniae liver abscesses often spread to distant organs such as the lungs, brain, and eyes. We present a case that highlights a liver abscess resulting from a metastasis from a urinary tract infection caused by K. pneumoniae.

 A 62-year-old female presented to the emergency department with complaints of epigastric pain, nausea, and vomiting. She reported a recent history of fever, chills, and malaise, which had been temporarily alleviated by paracetamol. Her medical history was significant for chronic hypertension, controlled with Amlodipine 5 mg daily, and prior episodes of uncomplicated urinary tract infections. Previous abdominal ultrasonography indicated no anatomical abnormalities of the urinary and hepatobiliary tract.  On initial examination, the patient was febrile; other vital signs were within normal limits. Physical examination revealed mild scleral icterus and tenderness in the right upper quadrant of the abdomen. Laboratory investigations showed leukocytosis with a white blood cell count of 14,840 cells/uL (reference range [R]: 4,109–10,900 cells/uL), elevated SGPT at 143 U/L (R: 12–78 U/L), total bilirubin of 3.15 mg/dL (R: 0–0.1 mg/dL) and creatinine of 1.18 mg/dl (R: 0.55 – 1.02 mg/dl, eGFR 52 ml/min). Both urine and blood cultures yielded growth of K. pneumoniae.  Empiric antibiotic therapy with intravenous Piperacillin-Tazobactam (4.5 grams every 8 hours) was initiated. Abdominal ultrasound revealed a complex mass in the left hepatic lobe. Contrast-enhanced CT confirmed the presence of a lobulated, hypoattenuating, and heterogeneously enhancing mass lesion measuring 5.7 × 6.2 × 6.2 cm (approximately 109 mL in volume), with peripheral enhancement and enhancing septations, consistent with a liver abscess.  Metronidazole (500 mg IV every 8 hours) was added to the antibiotic regimen, and the patient underwent interventional radiology-guided drainage of the abscess. Gram stain of the aspirate demonstrated gram-negative bacilli, and culture confirmed the presence of K. pneumoniae. Antibiotic therapy was subsequently adjusted to Cefepime (2 grams IV every 12 hours), and later to Ciprofloxacin (400 mg IV every 12 hours) based on susceptibility testing.  Despite appropriate medical therapy, the patient remained febrile, and repeat ultrasound showed no significant reduction in abscess size or volume. Surgical consultation was sought, and the patient underwent surgical drainage and deloculation of the abscess. Following the procedure, the patient became afebrile and demonstrated progressive clinical improvement.  She was discharged with a plan to complete an additional three weeks of oral antibiotic therapy. On outpatient follow-up, the patient reported no recurrence of symptoms, and repeat cultures were negative.

Klebsiella pneumoniae is a major cause of liver abscess in Asia, commonly originating from the gastrointestinal tract. However, our case report identified the urinary tract as an unusual source, suggesting that certain K. pneumoniae strains may colonize the urinary tract and spread hematogenously to the liver via the portal vein.  This unique blood supply make lymphatic dissemination also possible.