Risk Factors of Sepsis in Obstructive Acute Pyelonephritis Associated with Urinary Tract Calculi

Purpose: The aim of this study is to identify the risk factors for development of sepsis in patients with obstructive acute pyelonephritis (APN) associated with urinary tract calculi. Materials and Methods: Between January 2004 and December 2013, 73 patients with obstructive APN associated with upper urinary tract calculi were admitted to our institution. Medical records of 73 patients (14 men and 59 women, mean age of 57 years) were reviewed retrospectively. The risk factors for sepsis were analyzed using multivariate logistic regression analysis. Results: Of 73 patients, 37 (50.7%) developed sepsis. Old age and history of hypertension were more common in the sepsis group than in the non-sepsis group (p<0.001 and p=0.018). The white blood cell count, neutrophil count, plateletto-lymphocyte ratio, neutrophil-to-lymphocyte ratio (NLR), and C-reactive protein level were significantly higher in the sepsis group (p=0.011, p=0.001, p=0.042, p<0.001 and p=0.006, respectively). Lymphocyte count, platelet count, and albumin level were significantly lower in the sepsis group (p<0.001, p=0.008 and p<0.001, respectively). Multivariate logistic regression analysis indicated that old age (odds ratio [OR], 2.13; p=0.023), decrease in serum albumin level (OR, 4.27; p=0.041), and high NLR (OR, 3.83; p=0.037) were independent risk factors for development of sepsis. Conclusions: Elderly patients with obstructive APN associated with urinary tract calculi who have low serum albumin levels and high NLR should be treated carefully against development of sepsis.