A positive nitrite test was an independent risk factor for invasive bacterial infections in infants under 90 days of age with fever without source.

AIM: This study analysed the association between a positive nitrite dipstick test and an invasive bacterial infection (IBI) in infants younger than 90 days of age with fever without source (FWS). METHODS: We performed a secondary analysis of data from a prospective multicentre study of infants up to 90 days of age with FWS undergoing care in 19 paediatric EDs between October 2011 and September 2013. Invasive bacterial infection was defined as a positive blood or cerebrospinal fluid culture. RESULTS: The dipstick urinalysis was positive for nitrite or leucocyte esterase in 766 (22.5%) of the 3401 infants we studied, and 270 (35.2%) had a dipstick test that was just positive for nitrite. Overall, 107 were diagnosed with an IBI (3.1%). The IBI prevalence was 2.2% among patients with a normal urine dipstick, 4.4% if they had positive leucocyte esterase test results, 8.3% where the nitrite test was positive and 10.6% when both tests were positive. After multivariate analysis, a positive nitrite test remained an independent risk factor for IBI (odds ratio 2.7, 95% confidence interval 1.4-4.9). CONCLUSION: In infants under 90 days of age with FWS, a positive nitrite urine dipstick test was an independent risk factor for IBI.

Useful Predictive Factors for Bacteremia among Outpatients with Pyelonephritis.

Objective The aim of this study was to identify predictive factors for bacteremia conveniently and quickly among outpatients diagnosed with pyelonephritis. Patients All patients who were diagnosed with pyelonephritis at the outpatient clinic in the Department of General Medicine of Juntendo University Hospital from April 1, 2008, to June 30, 2015, were enrolled. Patients from whom blood cultures had not been taken were excluded. Methods Clinical information was extracted from medical charts. Factors potentially predictive of bacteremia were analyzed using a t-test and Fisher's exact test, followed by a multivariable logistic regression model analysis. Results Blood cultures were drawn from 116 patients, and 25 (22%) presented with bacteremia. A multivariate analysis with the age, chills, platelet count and urine nitrite test results revealed that older age, positive urinary nitrite test results and chills tended to be associated with bacteremia, respectively. [older age: unit odds ratio (OR) 1.02, p=0.052, 95% confidence interval (CI) 1.00-1.05, positive urinary nitrite test findings: OR 2.5, p=0.092, 95% CI 0.86-7.7, chills: OR 2.5, p=0.096, 95% CI 0.84-7.65]. The area under the receiver operating characteristic (ROC) curve of this model was 0.77. Regardless of age, positive urinary nitrite test findings were significantly associated with bacteremia (OR 3.1, p=0.033, 95% CI 1.1-9.2), and chills tended to be associated with bacteremia (OR 2.7, p=0.07, 95% CI 0.93-7.9) The area under the ROC curve of this model was 0.75. Conclusion Bacteremia should be considered in pyelonephritis patients with rapidly assessable factors in outpatient clinic. In particular, a model including a urinary nitrite test has the potential to aid in the prediction of bacteremia.

Clinical value of urine heparin-binding protein in the diagnosis of urinary tract infection / 中华检验医学杂志

Objective To dectect urine level of heparin-binding protein(HBP)in screening urinary tract infection(UTI).Methods A case-control study was performed.From June 2016 to December 2016, urine levels of HBP were detected by enzyme linked immunosorbent assay in 119 patients with definite UTI, 18 patients with probable UTI,58 patients with no UTI and 52 normal controls who were enrolled at Fudan University Hua Shan Hospital North.Meanwhile,urine leukocyte esterase test(U-LE)and urine nitrite test (U-NIT)were performed by urine dipstick analyzer.And count of urine WBC(U-WBC)was performed by urine formed elements analyzer.The overall level of each group was compared using Kruskal-Wallis H test. Two independent samples were compared by Mann-Whitney U test.The correlation between U-HBP, U-LE and U-WBC were assessed using Spearman′s rank coefficient.Receiver operating characteristic curves were constructed to illustrate the diagnostic power of U-HBP, U-LE, U-NIT and U-WBC for UTI.Results In definite UTI group,probable UTI group,no UTI group and normal control group,the levels of U-HBP, U-LE,U-NIT and U-WBC were significantly different(H values were 166.73,126.88,47.92 and 144.05, respectively,P<0.05).Areas under the receiver-operating characteristics curves(AUC)of U-HBP, U-LE,U-NIT and U-WBC were 0.948,0.836,0.671 and 0.897 respectively for the diagnosis of UTI.When a cut-off value of 69.20 ng/ml was used in U-HBP, the sensitivity and specificity for detection of definite UTI were 89.9%(107/119)and 89.1%(114/128),respectively.When U-LE at a cut-off value of 4+, the sensitivity was 76.5%(91/119)and specificity was 81.3%(104/128).When U-NIT at a cut-off value of 1+,the sensitivity was 36.1%(43/119)and specificity was 97.7%(125/128).When U-WBC at a cut-off value of 233.6/μl,the sensitivity was 82.4%(98/119)and specificity was 82.8%(106/128). A strong correlation was detected between U-HBP and U-WBC(r=0.896, P<0.05).The correlation between U-HBP and U-LE was also strong(r=0.798, P<0.05).Conclusions Heparin-binding protein in the urine was significantly better in diagnosis of UTI,compared with the other markers.It could probably be acted as an important new biomarker for diagnosis of UTI.

Can the Griess Nitrite Test and a Urinary Pus Cell Count of ≥5 Cells Per Micro Litre of Urine in Pregnant Women be Used for the Screening or the Early Detection of Urinary Tract Infections in Rural India?

OBJECTIVES: Urinary Tract Infection (UTI) is a common problem in pregnancy due to the morphological and the physiological changes that take place in the genitourinary tract during pregnancy. Screening methods may be useful, because a full bacteriological analysis could be reserved for those patients who are symptomatic or those who have positive screening test results. The exact prevalence of UTI in rural, pregnant women is unknown. The present study was undertaken to estimate the prevalence of UTI in pregnant women and for ascertaining the utility of the Griess Nitrite test and the Urinary Pus Cell Count of ≥5 cells per micro litre test for the screening or the early detection of UTI in them at primary health care clinics. Occurrence of urinary complaints was compared in UTI and non UTI women. METHOD: We conducted a study on 300 randomly selected, pregnant women from rural areas. Urine cultures, pus-cell counts and the Griess nitrite test were used for diagnosis of UTI. The screening tests for UTI were evaluated in terms of their sensitivity, specificity, Positive Predictive Value (PPV), Negative Predictive Value (NPV) and the percentage of correctly classified. RESULTS: In the present study, the prevalence of UTI was found to be 29/300 (9.6%, 95% confidence interval 9.57-9.63). The specificities of the two screening tests were comparable (97.05% and 94.47%). Also, the negative predictive values of the two tests were almost similar (97.77% and 96.96%). The percentage of correctly classified by the Griess nitrite test and the urine pus cell count were found to be 95.33% and 92.33% respectively. The proportion of the women with various urinary complaints was significantly higher (P<0.00) in the UTI subjects as compared to that in the non-UTI subjects. CONCLUSION: Urine culture remains the gold standard for the detection of asymptomatic bacteriuria. The Nitrite test of uncentrifuged urine was observed to be the best among the screening tests which were evaluated in terms of their efficiency and validity.

A study on the bacteriuria in the elderly who reside in a nursing home

BACKGROUND: Urinary tract infection(UTI) is one of the most common diseases dealt with by primary physicians. UTI is common in the elderly and has a great influence on the quality of the elderly's life. Thus, we conducted a study in one nursing home to find out the prevalence of bacteriuria and epidemiologic characteristics of the elderly. METHODS: The study was performed twice on April 12 and on May 4, 1999 among 108 subjects residing in a nursing home of Hanam City. The authors inquired the subjects pertaining to the history of UTI symptoms, collected urine samples by midstream clean-catch technique and catheterization and performed routine and microscopic urine analysis and urine culture. RESULTS: The overall prevalence of bacteriuria in subjects was 23.1%(25/108) ; 20% (3/15) in males and 23.7%(22/93) in females. The prevalence of the bedrriden subjects was 40.9%(9/22). Among the urine samples of 25 cases which were positive in the urine culture, E. Coli was found in 15 cases(60%). The sensitivity, specificity, positive and negative predictive value of pyuria for bacteriuria were 44.0%(11/25), 87.9%(73/83), 52.3%(11/21) and 83.9%(73/87), respectively, while those of nitrite test for bacteriuria were 64.0%(16/25), 97.5%(81/83), 88.8%(16/18) and 90.0%(81/90), respectively. The prevalence of bacteriuria increased by 16.23% as age increased by ten years using the Cochran-Armitage's linear trend test. CONCLUSIONS: The prevalence of bacteriuria in the elderly residing in a nursing home was higher than that of the elderly residing in a community. In the elderly over 60 years old, the prevalence of bacteriuria increased as the age increased. Immobility is considered as a risk factor of bacteriuria. Bacteriuria may be treated by antibiotics focused on E. Coli. Thus, we can expect improvement in the quality of life as well as extension of life span.