Jose Flores-Figueroa, Vianney Ortiz-Navarrete, Mercedes Paredes-Paredes, Fernando Rogelio Espinosa-Lopez, Luis Javier Castro-D'Franchis
(JM Research, Cuernavaca, Mexico)
Med Sci Tech 2017; 58:15-20
Urinary tract infection (UTI) is one of the most frequent nosocomial infections. Quantitative cultures (QC) are considered the most reliable diagnostic tool for diagnosis, but this method has a 48-h delay. There has been demonstrated an elevation of pro-inflammatory cytokines as an early response to UTI. We conducted a prospective study to determine the time of elevation of urinary IL-8 (UIL-8) compared to QC for diagnosing nosocomial UTI in urinary catheterized patients (UCP).
MATERIAL AND METHODS: Urinary QC were collected and measurement of UIL-8 was performed in hospitalized adult UCP. We took samples at the moment of catheterization and every 24 h thereafter until the development of UTI as determined by bacterial growth on QC. UIL-8 was measured using specific ELISA. The paired t test was used to compare the time differences between UIL-8 elevation and QC growth.
RESULTS: Sixteen patients were included. Median UIL-8 concentrations at the time of catheterization were 10 pg/mL (0–23) compared to 309±197 pg/mL at UTI diagnosis (p<0.0001). UIL-8 was significantly increased at least 24 h earlier than QC in 78% of patients. The higher achieved statistics were: Sensibility at 50 pg/mL (97.1%), specificity at 375 pg/mL (99.7%), positive predictive value at 375 pg/mL (95.0%), and negative predictive value at 50 pg/mL (96.7%).
CONCLUSIONS: UIL-8 concentration rise is well correlated to the presence of UTI and could be useful in the decision to start therapy without having the QC reports yet. These results confirm that UIL-8 can be used as an early diagnostic tool for nosocomial UTI.
Keywords: Cross Infection, Interleukin-8, Urinary Tract Infections