Meta-Analysis
Copyright ©The Author(s) 2022. Published by Baishideng Publishing Group Inc. All rights reserved.
World J Hepatol. Jun 27, 2022; 14(6): 1258-1268
Published online Jun 27, 2022. doi: 10.4254/wjh.v14.i6.1258
Spontaneous bacterial empyema in cirrhosis: A systematic review and meta-analysis
William Reiche, Smit Deliwala, Saurabh Chandan, Babu P Mohan, Banreet Dhindsa, Daryl Ramai, Abhilash Perisetti, Rajani Rangray, Sandeep Mukherjee
William Reiche, Department of Internal Medicine, CHI Creighton University Medical Center, Omaha, NE 68124, United States
Smit Deliwala, Department of Internal Medicine, Michigan State University at Hurley Medical Center, Flint, MI 48503, United States
Saurabh Chandan, Rajani Rangray, Sandeep Mukherjee, Division of Gastroenterology and Hepatology, CHI Creighton University Medical Center, Omaha, NE 68124, United States
Babu P Mohan, Daryl Ramai, Department of Gastroenterology, University of Utah, Salt Lake City, UT 84132, United States
Banreet Dhindsa, Division of Gastroenterology and Hepatology, University of Nebraska Medical Center, Omaha, NE 68198, United States
Abhilash Perisetti, Division of Gastroenterology, Parkview Health, Fort Wayne, IN 46845, United States
Author contributions: Reiche W acquisition of data, drafting the article, final approval; Deliwala S acquisition of data, analysis, interpretation of data, drafting the article; Chandan S conceptualization, study search, critical revision, final approval; Mohan B statistical analysis; Dhindsa B, Ramai D, Perisetti A data collection and study search; Rangray R and Mukherjee S critical revision, final approval
Conflict-of-interest statement: The authors deny any conflict of interest.
PRISMA 2009 Checklist statement: The PRISMA 2009 Checklist statement was utilized and is located in the supplementary material uploaded content.
Open-Access: This article is an open-access article that was selected by an in-house editor and fully peer-reviewed by external reviewers. It is distributed in accordance with the Creative Commons Attribution NonCommercial (CC BY-NC 4.0) license, which permits others to distribute, remix, adapt, build upon this work non-commercially, and license their derivative works on different terms, provided the original work is properly cited and the use is non-commercial. See: https://creativecommons.org/Licenses/by-nc/4.0/
Corresponding author: William Reiche, DO, Doctor, Department of Internal Medicine, CHI Creighton University Medical Center, 7500 Mercy Road, Omaha, NE 68124, United States. reichewilliam@gmail.com
Received: January 21, 2022
Peer-review started: January 22, 2022
First decision: March 16, 2022
Revised: April 6, 2022
Accepted: May 12, 2022
Article in press: May 12, 2022
Published online: June 27, 2022
ARTICLE HIGHLIGHTS
Research background

Spontaneous bacterial empyema (SBE) is analogous to spontaneous bacterial peritonitis (SBP); however, much less is understood regarding its incidence rate, treatment strategies, and management.

Research motivation

The current understanding of SBE is limited by small sample size and results regarding its association with ascites are conflicting. Previous studies have noted patients who have cirrhosis and SBE may have poorer outcomes therefore more information regarding its association with ascites/SBP, incidence, treatment, and effect on outcomes are needed.

Research objectives

To identify the incidence of SBE in patients with cirrhosis, the incidence of SBP in patients with cirrhosis, and the incidence of SBE in patients without concomitant ascites. Additionally, we performed a systematic review of the treatment and outcomes of SBE.

Research methods

We performed a meta-analysis using a random-effects model with pooled proportions and 95% confidence intervals (CI). We assessed heterogeneity using I2 and classic fail-safe to determine bias.

Research results

A total of 1334 patients had pleural effusions and the pooled incidence of SBE was 15.6% (CI 12.6-19; I2 50). Amongst patients diagnosed with SBE, the most common locations included right (202), left (64), and bilateral (8). Amongst our cohort, a total of 2636 patients had ascites with a pooled incidence of SBP of 22.2% (CI 9.9-42.7; I2 97.8). The pooled incidence of SBE in patients with cirrhosis but without concomitant ascites was 9.5% (CI 3.6-22.8; I2 82.5).

Research conclusions

SBE frequently occurs with concurrent ascites/SBP; our results suggest high incidence rates of SBE even in the absence of ascites. The pleura can be an unrecognized nidus and our findings support the use of diagnostic thoracentesis in patients with decompensated cirrhosis after exclusion of other causes of pleural effusion. Thoracentesis should be considered particularly in patients without ascites and when there is a high suspicion of infection. The need for diagnostic thoracentesis will continue to be important as rates of multi-drug resistant bacterial infections increase and antibiotic susceptibility information is required for adequate treatment.

Research perspectives

This study suggests the baseline incidence of SBE is high in patients with cirrhosis and diagnostic thoracentesis should be considered after underlying pulmonary and cardiac causes have been ruled out, especially when there is high concern for infection. High index of suspicion for SBE must be maintained especially in cirrhosis patients with pleural effusions and without underlying ascites. Timely treatment is warranted given high associated mortality of SBE. Future prospective studies are needed, as it remains unclear if long term prophylaxis against SBE is warranted in patients with decompensated cirrhosis.