COCHRANE REVIEW: ANTIBIOTIC THERAPY FOR SHIGELLA DYSENTERY

Monday, 29th of July 2013

ANTIBIOTIC THERAPY FOR SHIGELLA DYSENTERY

Christopher PRH, David KV, John SM, Sankarapandian V

Published Online:

August 8, 2010

Shigellosis is a bacterial infection of the colon that can cause diarrhoea, dysentery (diarrhoea with blood and/or mucus) and may lead to death. It occurs mainly in low- and middle-income countries where overcrowding and poor sanitation exist, and may lead to around 1.1 million deaths per year globally, mostly in children under five years.

The intention of giving antibiotics in shigellosis is to speed recovery, reduce the seriousness of the disease, and reduce the length of time patients are infective. However, some antibiotics can have serious side effects while others may not be effective against the Shigella bacteria.

The review examined both the effectiveness and the safety of antibiotics in treating Shigella dysentery. While antibiotics tested here appeared safe and effective, there was insufficient evidence to suggest which antibiotics were superior. More well designed trials will help inform decision making.

Background:

Shigella dysentery is a relatively common illness and occasionally causes death, worldwide. Mild symptoms are self-limiting but in more severe cases, antibiotics are recommended for cure and preventing relapse. The antibiotics recommended are diverse, have regional differences in sensitivity, and have side effects.

Objectives:

To evaluate the efficacy and safety of antibiotics for treating Shigella dysentery.

Search strategy:

In June 2009 we identified all relevant trials from the following databases: Cochrane Infectious Diseases Group Specialized Register; Cochrane Central Register of Controlled Trials (CENTRAL) (The Cochrane Library 2008, issue 4), MEDLINE, EMBASE, LILACS and the metaRegister of Controlled Trials (mRCT). We also checked conference proceedings for relevant abstracts, and contacted researchers, organizations, and pharmaceutical companies.

Selection criteria:

Randomized controlled trials of antibiotics for Shigella dysentery.

Data collection and analysis:

Four authors, working in pairs, independently assessed trial eligibility, methodological quality, and extracted data. We calculated risk ratios (RR) with 95% confidence intervals (CI) for dichotomous data, and used the random-effects model for significant heterogeneity. We explored possible sources of heterogeneity, when present, in subgroup analyses of participant age and percentage of participants with confirmed Shigella infection.

Main results:

Sixteen trials (1748 participants), spanning four decades and with differing sensitivity to Shigella isolates, met the inclusion criteria. Seven were judged to be at risk of bias due to inadequate allocation concealment or blinding, and 12 due to incomplete reporting of outcome data. Limited data from one three-armed trial of people with moderately severe illness suggest that antibiotics reduce the episodes of diarrhoea at follow-up (furazolidone versus no drug RR 0.21, 95% CI 0.09 to 0.48, 73 participants; cotrimoxazole versus no drug RR 0.30, 95% CI 0.15 to 0.59, 76 participants).

There was insufficient evidence to consider any class of antibiotic superior in efficacy in treating Shigella dysentery, but heterogeneity for some comparisons limits confidence in the results. All the antibiotics studied were safe. There was inadequate evidence regarding the role of antibiotics in preventing relapses.

Authors conclusions:

Antibiotics reduce the duration of Shigella dysentery.

Regularly updated local or regional antibiotic sensitivity patterns to different species and strains of Shigella are required to guide empiric therapy. More trials adhering to standard guidelines are required to evaluate the role of antibiotics in the treatment of severe forms of Shigella dysentery and in groups who are at high risk of complications.

This record should be cited as:

Christopher PRH, David KV, John SM, Sankarapandian V. Antibiotic therapy for Shigella dysentery. Cochrane Database of Systematic Reviews 2010, Issue 8. Art. No.: CD006784. DOI: 10.1002/14651858.CD006784.pub4

Assessed as up to date:

July 18, 2009

Clinical question:

How effective are antibiotics for treating Shigella dysentery?

Bottom line:

There was limited evidence that antibiotics reduce the duration of diarrhoea and the duration of fever compared to no antibiotic. There was inadequate evidence regarding the role of antibiotics in preventing relapses. There were no serious adverse events reported for any of the 13 antibiotics studied. The choice of antibiotic to use as first line against Shigella dysentery should be governed by periodically updated local antibiotic sensitivity patterns of Shigella isolates. Other supportive and preventive measures recommended by the WHO should also be instituted along with antibiotics (eg, health education and hand washing).

Caveat:

There was insufficient evidence to consider any class of antibiotic superior in efficacy in treating Shigella dysentery, but heterogeneity for some comparisons limits confidence in the results. Most of the trials had methodological limitations. These included inadequate reporting of the generation of allocation sequence, inadequate allocation concealment, and lack of blinding. The most common source of bias was failure to report outcome details for participants who were randomised but in whom Shigella could not be isolated from stool culture.

Context:

Shigellosis is a bacterial infection of the colon that can cause diarrhoea and dysentery and may lead to death. It occurs mainly in low and middle-income countries where overcrowding and poor sanitation exist, and may lead to around 1.1 million deaths per year globally, mostly in children under five years. Mild symptoms are self-limiting but in more severe cases, antibiotics are recommended for eradication and preventing relapse.

Cochrane Systematic Review:

Christopher PRH et al. Antibiotic therapy for Shigella dysentery. Cochrane Reviews 2009, Issue 4. Article No. CD006784. DOI: 10.1002/14651858.CD006784.pub2. This review contains 16 studies involving 1748 participants.

Authored by:

Brian R McAvoy