Neutrophil to lymphocyte ratio in diagnosing acute cholecystitis: a retrospective cohort study in a tertiary rural hospital

Background:Acute cholecystitis accounts for most of the hospital admissions related to gastrointestinal diseases. In approximately 90% of patients, inflammation develops due to obstruction of the cystic duct by one or more gall-tones. Delayed management can lead to increased morbidity, due to progression to severe cholecystitis, such as gangrenous change, abscess formation, and gallbladder perforation. The neutrophil to lymphocyte ratio is derived from the counts of circulating neutrophils and lymphocytes, both of which are major leukocyte subpopulations. The inflammation triggered release of arachidonic acid metabolites and platelet-activating factors results in neutrophilia, and cortisol induced stress results in relative lymphopenia, and thus, the neutrophil to lymphocyte ratio accurately represents the underlying inflammatory process. The objective of this study was to evaluate the utility of the neutrophil to lymphocyte ratio (NLR) as a prognostic indicator in patients with cholecystitis. And to identify a relevant NLR value that discriminates between simple and severe cholecystitis.Methods: A retrospective analysis of patient data compiled by assessment of operative findings documented and patient follow up recorded over the period encompassing three years (2015-2012) at RL Jalappa Hospital and Research Centre, Tamaka, Kolar, Karnataka, India.Results:Our study population comprised of 250 patients with simple cholecystitis (69.63%) and 109 patients with severe cholecystitis (30.36%). The NLR of 3.0 could predict severe cholecystitis with 70.5% sensitivity and 70.0% specificity. A higher NLR (≥3.0) was significantly associated with older age (p = 0.001), male gender (p = 0.001), admission via the emergency department (p <0.001), longer operation time (p <0.001), higher incidence of postoperative complications (p = 0.056), and prolonged length of hospital stay (LOS) (p <0.001).Conclusions:NLR ≥3.0 was significantly associated with severe cholecystitis and prolonged LOS in patients undergoing cholecystectomy. Therefore, preoperative NLR in patients undergoing cholecystits due to cholecystitis seemed to be a useful surrogate marker for severe cholecystitis.