Table 1 [11-12, 16-37] and Table 2 [8, 38-47] show the clinical characteristics and laboratory test results of patients with GFPLA-Kp (12 cases) and patients with GFPLA-Cp (24 cases). The mean ages of patients with GFPLA-Kp and patients with GFPLA-Cp were 67.08 ± 10.22 years and 66.70 ± 8.78 years, respectively. The proportions of patients with GFPLA-Kp and patients with GFPLA-Cp of male sex were 58.3% and 70.8%, respectively; however, there was no statistically significant difference between the 2 patient groups. It was also found that age >70 years was not a predictor of mortality in patients with GFPLA-Kp and patients with GFPLA-Cp.
Of the 12 patients with GFPLA-Kp, 11 (91.7%) were from Asia (4 from Japan, 3 from Taiwan, 2 from Korea, 1 from China, and 1 from Australia) and 1 (8.3%) was from the USA. In contrast, of the 24 patients with GFPLA-Cp, 11 (45.8%) were from Asia (6 from Japan, 1 from China, 2 from Hong Kong, and 2 from Australia), 9 (37.5%) were from Europe (2 from the UK, 2 from Spain, 2 from Germany, 2 from the Netherlands, and 1 from Belgium), and 4 (16.6%) were from the USA. With regard to the patients from Asia, the proportion of patients with GFPLA-Kp was greater than the proportion of patients with GFPLA-Cp (P=0.011).
Although Thng et al. reported that K. pneumoniae was the most common bacteria causing GFPLA, it is not clear what the most common bacteria causing GFPLA in patients with DM is [48]. Data showed that the most common underlying disease in patients with GFPLA-Kp was DM (83.3%). Of the 24 patients with GFPLA-Cp, 10 (41.6%) had DM, 6 (25%) had malignant tumors (1 patient with pancreatic cancer, 2 with gastric cancer, 2 with colon cancer, and 1 with HCC), 3 (12.5%) had cholangitis, 3 (12.5%) were previously in good health, 1 (4%) had undergone a hemi-hepatectomy for liver metastasis of a neuroendocrine tumor with an unknown primary site, and 1 (4.1%) had received a liver transplant for alcoholic cirrhosis. DM was more prevalent in patients with GFPLA-Kp than in patients with GFPLA-Cp (P=0.032). The results showed that DM is strongly associated with GFPLA-Kp. All but 3 patients (91.3%) presented with fever and 2 patients (8.3%) had no localizing signs.
Positive results of blood and pus cultures, blood culture, and pus culture were obtained in 6 patients (50%), 5 patients (41.6%), and 1 patient (8.3%) with GFPLA-Kp, respectively. Furthermore, positive results of blood culture, pus culture, and blood and pus cultures were obtained in 19 patients (79.1%), 3 patients (12.5%), and 2 patients (8.3%) with GFPLA-Cp, respectively. The proportion of positive blood culture results was higher in patients with GFPLA-Cp than in patients with GFPLA-Kp (P=0.03) compared to the proportion of positive blood and pus culture results. However, there were no statistically significant differences in the results of blood and pus cultures, blood cultures, or pus cultures between patients with GFPLA-Kp and patients with GFPLA-Cp.
With regard to laboratory investigations (Table 3 [11-12, 16-37] and Table 4 [8, 38-47]), patients with GFPLA-Cp had higher levels of aspartate aminotransferase (AST) (869.20 ± 583.02 IU/L versus 233.12 ± 98.19 IU/L, P=0.007) and alanine aminotransferase (ALT) (609.00 ± 516.26 IU/L versus 199.85 ± 74.93 IU/L, P=0.034) than patients with GFPLA-Kp at hospital admission. However, no statistically significant differences were found in alkaline phosphatase levels between the 2 patient groups. The hemoglobin, bilirubin, and lactate dehydrogenase (LDH) levels in patients with GFPLA-Cp were 6.88 ± 5.26 g/dL, 6.30 ± 7.08 mg/dL, and 1867.74 ± 2813.59 IU/L, respectively. These laboratory index indicated a high incidence of hemolysis.
Because ultrasonography cannot reliably depict the detailed internal structure of the gas-containing lesions, the X-Ray, CT and MRCP findings were assessed in GFPLA-Cp and GFPLA-Kp. With regard to radiological investigations, all patients (except 1 unmentioned case) with GFPLA-Cp and all patients with GFPLA-Kp were diagnosed using computed tomography (CT), as it is the most reliable technology for diagnosing GFPLA caused by these organisms. Similarly, Lee et al. reported a 100% detection rate with CT [2]. Abdominal palpation and ultrasonography were less reliable for diagnosis. The changes on CT between the patient groups were similar and include the presence of low attenuation areas and cavity formation with or without gas in the liver. In contrast, these same changes were not well defined on abdominal palpation and ultrasound in the patient groups.
All 12 patients with GFPLA-Kp had solitary abscesses. Of the 24 patients with GFPLA-Cp (with the exception of 2 patients that were not specified), 21 patients (95.4%) had solitary abscesses and 1 patient (4.5%) had multiple abscesses. The abscesses were larger in patients with GFPLA-Cp than in patients with GFPLA-Kp (15.98 ± 21.93 cm versus 8.16 ± 4.44 cm); however, the difference in abscess size between the patient groups was not statistically significant. Abscesses of diameter ˃5 cm were found in 83.3% of patients with GFPLA-Kp and in 62.5% of patients with GFPLA-Cp. The location of abscesses (right, left, and both lobes) was compared using the χ2 test and no statistically significant differences were observed.
The treatment of GFPLA-Kp and GFPLA-Cp include antibiotic therapy, surgical debridement and drainage. For GFPLA-Kp and GFPLA-Cp, it is important to treat antibiotics before drug sensitivity test. However, we found that surgical debridement or drainage was performed in all 12 patients (100%) with GFPLA-Kp and in 5 patients (20.8%; 3 DM and 2 non-DM) with GFPLA-Cp. In other words, more patients with GFPLA-Kp received surgical debridement or drainage than patients with GFPLA-Cp (P<0.001). The survival rate of patients with GFPLA-Kp who received surgical debridement or drainage was higher than that of patients with GFPLA-Cp who received the same treatment (P=0.002).
Considering the outcomes of GFPLA-Kp and GFPLA-Cp, twelve patients (50%) with GFPLA-Cp died as a result of different complications. This mortality rate is higher than that of patients with GFPLA-Kp (16.7%). However, no statistically significant differences in mortality rate between the patient groups were found using the χ2 test. There were also no statistically significant differences in the rates of death within 24 hours of hospital admission between DM and non-DM patients with GFPLA-Cp. Other cases have improved or even cured.