Analysis of clinical and CT characteristics of patients with Klebsiella pneumoniae liver abscesses: an insight into risk factors of metastatic infection

• Unilocular liver abscess is associated with septic pulmonary embolism.
• Septic pulmonary embolism is associated with extra-pulmonary infection.
• Diameter of abscess is a predictor of extra-pulmonary metastatic infection.

PurposeTo compare the clinical and CT characteristics of patients with Klebsiella pneumoniae liver abscess (KPLA), with or without metastatic infection.Materials and MethodsClinical information (age, sex, clinical symptoms, underlying disease, hematological parameters, abscess-related mortality) and CT characteristics of abscesses were analyzed to investigate associations with metastatic infection. Metastatic infections were divided into septic pulmonary embolism (SPE) and extra-pulmonary metastatic infection (EMI).ResultsWe identified 66 consecutive patients with KPLA. Metastatic infection occurred in 22/66 patients (33.3%); 8/66 (12.1%) patients had SPE, 6/66 (9.09%) patients had EMI; and 8/66 (12.1%) patients had both SPE and EMI. Patients with SPE were younger than patients without SPE (47.7 ± 13.7 y vs.55.6 ± 12.0 y; p = 0.03). Unilocular abscess was significantly more common in patients with SPE than the non-SPE group (43.75% vs 18.0%, p = 0.036). The mean maximal diameter of EMI was 56.5 ± 21.3 mm and was significantly smaller than that of the non-EMI which was 79.9 ± 31.4 (p = 0.011). SPE was significantly associated with development of EMI (50% vs17.3%, p = 0.011).ConclusionUnilocular liver abscess is associated with SPE, and SPE is strongly associated with EMI among patients with KPLA. A maximal diameter of KPLA<55 mm can be used as a predictor of EMI.