Effectiveness of antiseptics in the bacterial load reduction after septic wound dressing at Bugando Medical Centre, Mwanza, Tanzania

TL;DR

This study shows that using povidone-iodine during wound dressing significantly reduces bacterial load, including drug-resistant strains, in septic wounds at a hospital in Tanzania.

Contribution

The study evaluates the effectiveness of antiseptics in reducing bacterial load in septic wounds, with a focus on multidrug-resistant bacteria.

Findings

Bacterial culture positivity decreased from 71.9% to 39.4% after wound dressing.

Povidone-iodine was independently associated with reduced odds of culture positivity after dressing.

The proportions of ESBL-producing Gram-negative bacteria and MRSA were significantly reduced after dressing.

Abstract

septic wounds due to multidrug-resistant bacteria (MDR) are costly and result in adverse patient outcomes. Despite the fact that various antiseptics are routinely used for wound dressing, their effectiveness on bacterial load reduction remains to be evaluated to ascertain the usefulness of this step prior to antimicrobial therapies.

a cross-sectional analytical study was conducted among 203 patients with septic wounds at Bugando Medical Centre (BMC). Wound swab samples before and after dressing were collected, and cultured to quantify the total bacteria, extended-spectrum beta-lactamase-producing (ESBL) Gram-negative bacteria, and Methicillin-resistant Staphylococcus aureus (MRSA) load reduction.

half of the wounds were due to road traffic accidents. A total of 146 (71.9%) patients had positive aerobic culture before wound dressing, which decreased to 39.4% (80/203) after dressing (p-value < 0.001). The median (IQR) of total bacterial load before and after dressing was 205.5 (112-330) and 128 (34.5-235) CFU/mL, respectively (p-value<0.001). The proportions of ESBL-producing Gram-negative bacteria and MRSA were 34.0% and 39.9%, respectively, before dressing (and significantly reduced to 20.2% and 11.3%, respectively, after dressing). Povidone-iodine was independently associated with decreased odds of culture positivity after wound dressing [OR: 95% CI = 0.09 (0.01-0.63), p-value =0.016].

bacterial culture positivity was halved after septic wound dressing. Povidone-iodine significantly reduced both the total bacteria and MDR bacterial load in these wounds. Routine monitoring of antiseptics´ effectiveness is reiterated as a pivotal pre-requisite step prior to antibiotic therapies in septic wound management.

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