Review of Shigella Bacterial Infections in Children
Overview of Shigella Infections
A comprehensive review study examined Shigella bacterial infections, which are a significant cause of childhood diarrhea in developing countries. These infections can be severe, with fatality rates reaching as high as 28% among critically ill children. Common symptoms include stomach cramps, fever, diarrhea, and in severe cases, dysentery. Dysentery is characterized by inflammation of the colon, leading to diarrhea that may contain blood, pus, and mucus. While Shigella is a prevalent cause of dysentery, other pathogens can also contribute to this condition.
Current WHO Guidelines
The World Health Organization (WHO) has established guidelines for managing diarrhea caused by Shigella infections, emphasizing patient rehydration and recommending antibiotic treatments primarily for children with dysentery. In many developing nations, access to laboratory tests for accurate diagnosis is limited, making dysentery a practical marker for Shigella infections. However, it is crucial to note that not all severe Shigella cases result in dysentery. Relying solely on this symptom might overlook children who could benefit from antibiotics. Researchers from the University of Washington in Seattle reviewed existing evidence to determine if these guidelines require updates, with their findings published in Lancet Global Health.
Research Findings
Study Methodology
The researchers conducted three extensive reviews of published studies that addressed the following areas: mortality rates associated with Shigella, the effectiveness of dysentery as a diagnostic tool for Shigella infections, and the efficacy of antibiotic treatments in children with Shigella or dysentery. A total of sixty studies were included, comprising 13 focused on mortality, 27 on the diagnostic reliability of dysentery, and 20 on antibiotic treatment efficacy.
Dysentery as a Diagnostic Indicator
The analysis revealed that Shigella infections were linked to mortality among children suffering from diarrhea. By synthesizing data from various studies, it was determined that Shigella infection—regardless of the presence of dysentery—was more strongly associated with mortality than dysentery itself. In fact, while Shigella is frequently found in children with dysentery, the majority of Shigella-infected children do not exhibit dysentery symptoms. Furthermore, the diagnostic sensitivity of dysentery for identifying Shigella infections appears to have diminished over time, potentially due to the evolving prevalence of various Shigella strains.
Antibiotic Efficacy
Most antibiotic trials evaluating treatments for confirmed Shigella infections were conducted on children with dysentery, showing minimal differences in effectiveness across various antibiotics. Given the diverse settings of these studies, drawing definitive conclusions about treatment efficacy was challenging.
Recommendations and Conclusions
Need for Guideline Reevaluation
The researchers concluded that while the existing WHO guidelines effectively address dysentery management, they may fail to identify children with Shigella infections who do not present with dysentery. Healthcare providers should remain vigilant, recognizing that the absence of dysentery does not rule out Shigella as a potential cause of diarrhea, nor does it imply a lower risk of mortality. Special attention should be given to particularly vulnerable populations, including children under two years of age and those suffering from malnutrition.
Call for Clinical Trials
There is an urgent need for clinical trials aimed at developing targeted treatment strategies for non-dysenteric Shigella infections to enhance care for affected children.
Written by Julie McShane, Medical Writer
Reference: Tickell K, Brander R, Atlas H, et al. Identification and management of Shigella infection in children with diarrhea: a systematic review and meta-analysis. Lancet Global Health 2017;5:e1235-48.