关键词: 肾绞痛, 泌尿道感染, 年龄, C反应蛋白质, 预测, 影响因素分析

Abstract: Background　Acute renal colic（ARC） is an emergency that can be treated conservatively，but its combination with urinary tract infection（UTI） can be life-threatening.Infection evaluation parameters include white blood cell count（WBC） and C-reactive protein（CRP） levels，but they may not significant increase.Objective　To evaluate the prevalence of UTI in ARC patients diagnosed based on urine culture，and the predictive value of emergency routine blood and urine tests in ARC with UTI.Methods　200 consecutive patients with ARC due to ureteral calculi were recruited from Emergency Department，Hainan General Hospital from December 2017 to December 2018，196 ARC patients met the inclusion and exclusion criteria，including 26 with UTI（infected group） and 170 without（non-infected group） diagnosed by 3 times of urine culture.General information，including gender，age，time from onset of symptoms to emergency visit，average temperature，history of diabetes and immunodeficiency was collected.White blood cell count，and serum CRP were measured，and nitrite urine test and midstream urine culture were performed.Multivariate logistic regression analysis was used to explore the influencing factors of emergency ARC with UTI.ROC curve analysis was used to evaluate the clinical value of predictive parameters in emergency ARC with UTI.Results　The infected group had higher age，higher prevalence of positive result of nitrite in urine and higher average serum CRP than non-infected group（P<0.05）.Multivariate Logistic regression analysis showed that age，nitrite in urine，and CRP were the influencing factors of UTI in ARC patients（P<0.05）.For the prediction of UTI in ARC，the AUC of age was 0.754〔95%CI（0.688，0.813）〕 with 65.4% sensitivity，76.5% specificity，93.5% negative predictive value（NPV） and 29.8% positive predictive value（PPV） when the optimal cut-off point was determined as 56 years old，the AUC of serum CRP was 0.682〔95%CI（0.612，0.747）〕 with 53.9% sensitivity，80.6% specificity，91.9% NPV and 29.8% PPV when the optimal cut-off point was determined as 8.3 mg/L，and the AUC of positive result of nitrite in urine was 0.698〔95%CI（0.597，0.905）〕 with 69.2% sensitivity，93.0% specificity，94.2% NPV，and 30.3% PPV.Conclusion　Age，nitrite in urine，and serum CRP are associated with UTI in ARC.≥56 years old，serum CRP≥8.3 mg/L，and positive nitrite result in urine may have higher predictive value for UTI in ARC.

Key words: Renal colic, Urinary tract infections, Age, C-reactive protein, Forecasting, Root cause analysis