Does antibiotics prophylaxis compared to no antibiotics prophylaxis prevent recurrent cellulitis?

ELECTRONIC SEARCHES:

-Cochrane (Cochrance Central Register of Controlled Trials (CENTRAL), CDSR, HTA, DARE, NHS EED)

- MEDLINE via OVID SP

- EMBASE

- CINAHL via EBSCOhost

- Guidelines (UK NICE, US Guidelines Clearinghouse, Scotland SIGN)

- TRIP Database

ONGOING TRIALS:

- Clinical Trials.gov

- World Health Organization ICTRP

SEARCHING OTHER SOURCES:

- Contacting authors of the Patch I Trial

We will not impose a language restriction to our searches

We will include randomised controlled trials, systematic reviews as well as evidence based clinical practice guidelines in our review.

Cellulitis is an acute, subacute or chronic inflammation of the dermis and sub dermal tissues in which an infective, generally bacterial cause is assumed or proven.

Inclusion: we will include patients aged 16yrs and above, and after 1 or more episodes of cellulitis.

Exclusion: we will exclude participants with cellulitis secondary to filarial lymphoedema.

The target intervention will be any antibiotics against recurrent cellulitis.

(any form of delivery/dose/duration of antibiotics will be considered)

Inclusion:

Any RCT, systematic review or guidelines that compare antibiotics prophylaxis versus no antibiotics prophylaxis for prevention of recurrent cellulitis in any setting.

The control group will be patients without prophylactic antibiotics (Other forms of standard care e.g. local skin care, are allowed ).

Recurrent cellulitis is common, resulting in readmissions in a proportion of these patients. This systematic review looks at trials and guidelines that address the role of prophylatic antibiotics in patients with past episode(s) of cellulitis.

Primary outcomes

We will look at the recurrence of cellulitis (number of patients as well as number of episodes per patient).

We will also look at the total number of recurrences within a time period.

Recurrence must be diagnosed by a physician (the type of physician will be noted eg dermatologist versus non-dermatologist ).

There is no limit to the follow up period after completion of antibiotics.

Secondary outcomes

We will look at the time to next episode of recurrence (e.g. mean time, median time, SD).

We will look out for any adverse events (e.g. allergic reaction, nausea).

There is no limit to the follow up period after completion of antibiotics.

Two authors will independently review the articles, and decide on the inclusion of studies, having read the methods section of each study and applied the stated criteria. We will resolve differences by consensus and with consultation with a third author.

Two investigators will independently assess and rate the methodological quality of each trial using the Cochrane Collaboration tool for assessing risk of bias. We will judge the quality of the studies by evaluating the studies for the following six domains:

1. Random sequence generation

2. Allocation concealment

3. Blinding of participants and personnel

4. Incomplete outcome data

5. Selective outcome reporting

6. Other sources of bias

We will evaluate each study and assess separately for these domains. We will judge each explicitly as follows.

1. Low risk of bias

2. High risk of bias

3. Unclear risk (lack of information or uncertainty over the potential for bias)

A short narrative (descriptive) synthesis will be done summarizing the risk of bias and study quality for each study, as well as across studies. A narrative synthesis of the findings from the included studies will be done, discussing the type of interventions and controls used, target population characteristics, type of outcomes measured. We will provide summaries of intervention effects for each study by calculating risk ratios (for dichotomous outcomes) or standardised mean differences (for continuous outcomes).

We will consider the appropriateness of meta-analysis in the presence of significant clinical or methodological/statistical heterogeneity. We will perform meta-analyses using the Cochrane Collaboration Review Manager software (RevMan).

Initially we will pool the results using a Mantel-Haenszel fixed-effects meta-analysis (for binary outcomes) or the Generic Inverse Variance meta-analysis (for continuous variable), and estimating standardised mean differences for continuous outcomes and risk ratios for binary outcomes. These will use 95% confidence intervals and two sided P values for each outcome.

We may use a random effects meta-analysis for estimates with high heterogeneity to produce a more conservative effect estimate. Random effects may be used for pooling of clinically heterogeneous populations, interventions, or outcomes, as well as methodologically heterogeneous studies. Statistical indications of heterogeneity between the studies in effect measures will be assessed using both the Chi-squared test and the I-squared statistic. We will consider an I-squared value greater than 50% indicative of moderate heterogeneity and >75% indicative of substantial heterogeneity.

We will conduct sensitivity analyses based on study quality. We will use stratified meta-analyses to explore heterogeneity in effect estimates according to: study quality; study populations (1st occurence vs 2nd or more recurrence); intervention content (i.e. type of antibiotic used), and the effect of small and large studies on the effect estimate. We will also assess evidence of publication bias if there are an adequate number of studies obtained for this analysis to be useful.

1. We will compare 2 populations (one population with 1 or more previous episodes of cellulitis before enrollment, and the other population with 2 or more previous episodes of cellulitis before enrollment).

2. We will analyse PO penicillin versus IM penicillin.

3. Penicillin versus other types of antibiotics.

Choon Chiat Oh

Singapore General Hospital

Dermatology Unit

Outram Road

Singapore 169608

Singapore

oh.choon.chiat@sgh.com.sg

Singhealth

www.singhealth.com.sg

Dr Choon Chiat Oh, Dermatology Unit, SIngapore General Hospital, Singhealth, SIngapore
Dr Henry Ko, Centre for Health Services Research, Singhealth, Singapore
Dr Piotr Chlebicki, Department of Infectious Diseases, Singapore General Hospital, Singhealth
Dr Haur Yueh Lee, Dermatology Unit, Singapore General Hospital, Singhealth
Dr Nsair Safdar, Section of Infectious Diseases, Department of Medicine, University of Wisconsin Medical School, Madison, WI
Dr Dennis G Maki , Section of Infectious Diseases, Department of Medicine, University of Wisconsin Medical School, Madison, WI

25 June 2012

25 June 2013

Not applicable

None known

English

Singapore, United States of America

Subject indexing assigned by CRD

Anti-Bacterial Agents; Cellulitis; Drug Administration Schedule; Humans; Recurrence; Streptococcal Infections

11 September 2012

11 September 2012