The intra-abdominal infection such as PLA can lead to high mortality rate caused by sepsis if not recognized early and managed promptly. How to promptly provide a precise diagnosis and optimal therapy is crucial. With the routine clinical practice of using CT imaging for identifying intra-abdominal infection in China, this two-arm, retrospective study collected clinical data to evaluate the effects of early adoption of non-enhanced CT imaging (i.e., within 48 hours after admission) on the disease status and recovery in patients with PLA. For patients receiving an early or late CT scan, the disease severity of PLA (i.e., SIRS, qSOFA, and CRP) was comparable though the WBC level in the early CT group was significantly lower than the late CT group. This study revealed that the hospital stay of patients with PLA receiving an early CT scan was shorter than those receiving a late CT scan. Additionally, patients with an early CT scan received drainages earlier and had lower burden of antibiotic use during hospitalization. These findings imply that early CT scan within 48 hours after admission may enable early diagnosis of PLA for effective and prompt treatment.
Compared with other Western studies, outcomes of patients receiving CT scan within 48 hours after admission in the current study were also more favorable, as reflected by a shorter length of stay (15.0 days) than other Western real-world studies (Italy: 24 days; UK: 22 days)6,14 and a morality rate of 0% versus other studies (Italy: 11 patients [10.1%]; UK: 8 patients [12.3%])6,14. In the comparison with Asian studies, the length of hospital stay and in-hospital mortality in our study were also better than a Taiwanese study (19.6 days; 6.3%)15; and similar to another Chinese study (14.5 days; 1.5%)8. Although the differences in patients and disease characteristics (lesion size, pathogenesis, and comorbidity) between studies and races are inevitable, CT scanning conducted in early 48 hours may be a potential first-line diagnostic tool for identifying liver abscess. Early diagnosis allows physicians plan treatment strategy ahead, which may contribute to improve disease status and a faster recovery.
On the other hand, early adoption of CT scanning for patients with PLA also significantly shorten the time to initiating drainages after admission, and was associated with lower prescription rate of 2nd generation cephalosporin and fluoroquinolone and higher prescription rate of 3rd generation cephalosporin. Considering that Klebsiella pneumoniae, a gram-negative bacterium that is sensitive to 3rd generation cephalosporin, is the most common pathogen causing PLA in Asia, such treatment pattern was in line with the general practice that patients with PLA were usually treated with 3rd generation cephalosporin16–18. On the other hand, broad-spectrum antibiotics were preferred to treat patients in the late CT group, implying that the clinician might give broad-spectrum antibiotics to treat infections without a precise diagnosis for patients receiving a late CT scan. Taken together, these results suggested that early adoption of CT scanning may achieve early diagnosis and assist clinicians in treating patients with adequate antibiotics combined with drainages, resulting in the reduction of length of hospital stay and in-hospital mortality.
Furthermore, 51.7% of eligible patients (n = 29; data not shown) in the current study had the lesion located in segment 7/8 of liver. This study also presented that first-line CT scanning in the emergency department enabled to detect the lesion in the liver segment early where ultrasound examination may fail to detect the lesion thoroughly.
There are some limitations in this study. First, our findings were not generalizable because it was a single-center study conducted in China. Second, the number of enrolled patients per group was imbalanced, despite their baseline data were generally homogeneous. Third, we observed that the WBC level was significantly lower in the early CT group (lesion size: 5.9 cm) than the late CT group (lesion size: 6.5 cm), and such difference may bias the comparison of disease status and management between groups. Results should be interpreted with caution due to the imbalance in the patient pool, and a randomized-controlled study is required to validate our findings. Forth, 56.5% of patients (n = 43) were infected by Klebsiella pneumoniae, diverse pathogens causing PLA may influence the therapeutic decision and strategy; therefore, results need to be interpreted with care2,19. Final, to our knowledge, this study might be the first research to evaluate the impact of adopting early CT imaging on PLA patients in comparison with late CT imaging. The cutoff time duration of applying CT was defined by emergency clinicians’ experience. However, these data also reflected the routine management of PLA in China.