Clinical and microbiologic evaluation of chronic leg ulcers: a cross-sectional study.

OBJECTIVE

This study aimed at evaluating the flora and bacterial load of chronic leg ulcers (CLUs) according to the clinical judgment of colonization or infection.

DESIGN

This was an analytical and cross-sectional study.

SETTING

This study was conducted in an outpatient wound care unit in the Dermatology Department of the Botucatu School of Medicine-UNESP, Brazil.

PARTICIPANTS

The participants were patients with CLUs who did not use systemic antibiotics.

METHODS

The ulcers were clinically divided into 3 groups: ulcers with good granulation tissue (GGT), critical colonization (CC), and infection. Secretion was collected from a 1-cm area using a swab and seeded by the semiquantitative method.

OUTCOME MEASURES: The main outcome measures were genus and species of the bacteria found in the cultures and result of the semiquantitative culture correlating with the clinical diagnosis of GGT, CC, and infection.

MAIN

RESULTS

Seventy-seven ulcers were evaluated: 27 with GGT, 29 with CC, and 21 with infection. Gram-negative bacteria were most often found in all groups (81%): Pseudomonas aeruginosa, in granulation and colonized ulcers, and Proteus mirabilis, in infected ulcers. Ulcers from the infected group showed higher bacterial load.

CONCLUSIONS

The flora of CLUs was predominantly constituted by gram-negative bacteria, and P aeruginosa was the most prevalent. The bacterial load of infected ulcers was higher as compared with the others, although some ulcers with GGT also presented a high load. The interpretation of microbiologic tests based on the swab techniques and even on semiquantitative analysis requires close clinical correlation.