Evaluation the intestinal level of LCN2/NGAL in patients with Clostridium difficile infection in the south of Iran

Abstract
Clostridium difficile is a Gram-positive obligate anaerobic bacterium that recognized an important pathogen of humans. The present study aimed to evaluate the intestinal level of neutrophil gelatinase-associated lipocalin (NGAL) in patients with C. difficile infection (CDI) as a disease activity marker in the south of Iran. This cross-sectional study conducted from October 2017 to June 2018 on patients referred to Nemazee and Amir Hospital in Shiraz, South of Iran. Patients less than two years old were excluded from the study. The study population was consist of 46 cases (Symptomatic patients that confirmed as a CDI), and 21 control individuals (Asymptomatic patients colonized by C. difficile). C. difficile isolates were identified by conventional microbiological producers and amplification of housekeeping gene by PCR method. The level of NGAL was determined by enzyme-linked immunosorbent assay (ELISA) according to the instructions of the kit manufacturer. The results showed that the level of NGAL in symptomatic patients' (case group) was higher than asymptomatic carriers (control group), 5.9 ng/mL vs. 4.1 ng/mL; however the observed difference was not statistically significant. Also, in both groups, the mean level of NGAL was significantly higher in patients with gastrointestinal diseases than others. In summary, despite all the limitations, the results of the present study indicate that the intestinal level of NGAL is a biological indicator of intestinal inflammation, regardless of CDI. However, further study needs to elucidate the role of NGAL in inflammation caused by bacterial infections.