Is Nitrite Negativity in Urine Analysis an Indicator of Antibiotic Resistance?

Introduction: Studies have reported a correlation between anegative nitrite on urine analysis and resistance tocephalosporin in urine cultured isolate in cases of UTI. Nitritenegativity has therefore been suggested as an aid forphysicians in choosing initial empiric specific antimicrobialtherapy in patients with UTI. Other studies however haveshown contrary results.Study Question: Does whether urinary nitrite test negativityidentify pediatric patients with a higher likelihood of antibioticresistance in bacterial isolates from urines sample cultures.Method: Retrospective chart review of all pediatric patientsfrom birth to 14 years old who received a diagnosis of UTIbased on urine analysis and cultures. We analyzed urineanalysis result, nitrite test result, urine culture and antibioticsensitivity pattern and statistically looked for any correlation ofnitrite negativity on urine analysis with antibiotic resistancepattern of bacterial isolates from urine cultures.Results: No significant statistical difference found betweenantibiotic sensitivity rates of isolates grown from cultures ofnitrite-positive & from nitrite-negative urinary specimens.Conclusions: Physicians should choose initial antimicrobialagent based on knowledge of locally prevalent patterns ofantibiotic resistance, and not on urinary nitrite test results.

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.

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.