Cytokine levels as biomarkers for leptospirosis patients.

Inflammatory mediators were suggested to be biomarkers for prediction of disease severity. In this study, we investigated the levels of IL-6, IL-8, IL-10 and TNF-α in leptospirosis patients with mild or severe illnesses. Sera samples were divided into two groups. The OI group and NOI groups included sera from patients with and without organ involvement, respectively. Each group consisted of 20 pairs of sera. Twenty-five sera from healthy individuals were included as controls. Cytokine levels were compared. Although IL-6, IL-8 and IL-10 levels in acute sera from the OI group were significantly higher than NOI group, only IL-8 level was significantly higher in the OI group when cytokine levels in convalescent sera were compared. TNF-α, an inflammatory cytokine widely studied in leptospirosis was not significantly different between two groups of patients. Our data suggested that IL-6, IL-8 and IL-10 were involved in disease severity. However, time of specimen collection could affect the significant levels of cytokines especially as biomarkers for monitoring disease severity.

The use of selective media for the isolation of Pseudomonas pseudomallei in clinical practice.

Ashdown's selective-differential agar medium, with or without preenrichment in selective broth, was evaluated for the isolation of Pseudomonas pseudomallei from 1972 clinical specimens obtained from 643 subjects in Northeast Thailand; 226 patients proved to have meliodosis. The use of Ashdown's medium significantly increased the frequency of recovery of P. pseudomallei from sites or specimens with an extensive normal flora (throat, rectum, wounds and sputum) as compared to the recovery on blood and MacConkey agars (p less than 0.01). The isolation frequency from throat, rectal and wound swabs was further increased by the use of the broth pre-enrichment. The colonial morphology of P. pseudomallei on Ashdown's medium was sufficiently characteristic to allow presumptive identification. With the use of these selective media it was possible to culture P. pseudomallei from throat swabs taken from 87% of the patients from whom the organism could also be isolated from corresponding tracheal aspirates or sputum specimens. P. pseudomallei was isolated from rectal swabs taken from 51 patients, the first time that faecal excretion of the organism has been demonstrated in man. The diagnosis of melioidosis would not have been confirmed bacteriologically in eight patients (3.5%) without the use of the selective media. It is suggested that, in areas endemic for melioidosis, all sputum specimens should be cultured on selective media, such as Ashdown's. For the investigation of clinically suspected cases of melioidosis, and for follow-up during treatment of the disease, the use of broth pre-enrichment is recommended for specimens obtained from sites with an extensive normal flora.