Accuracy of NGAL as a Biomarker for Urinary Tract Infection in Young Febrile Children: An Individual Patient Data Meta-Analysis.

OBJECTIVE: To compare the accuracy of urine neutrophil gelatinase-associated lipocalin (NGAL) and leukocyte esterase (LE) for the diagnosis of urinary tract infection (UTI) in children. STUDY DESIGN: We performed a systematic review and individual patient data meta-analysis of studies that examined urine NGAL as a marker of UTI in children <18 years of age. We created a standardized definition of UTI and applied it to all included children. We compared sensitivity, specificity, and the area under the receiver operating characteristic curve (AUC) of NGAL with LE. RESULTS: We included individual patient data from 3 studies for a total of 845 children. Included children had a mean age of 0.9 years (SD, 0.6 years). Using a cutoff of 32.7 ng/mL, NGAL had a sensitivity of 90.3% (95% CI: 83.2%-95.0%) and specificity of 93.7% (95% CI: 91.7%-95.4%) for the diagnosis of UTI. LE, using a cutoff of ≧ trace had a sensitivity of 81.1% (95% CI: 72.5%-87.9%) and specificity of 97.0% (95% CI: 95.4%-98.1%). The AUC for NGAL was 0.95 (95% CI: 0.92-0.98). The AUC for LE was 0.90 (95% CI: 0.86-0.93). CONCLUSION: In young, febrile children, urinary NGAL is more sensitive for the diagnosis of UTI than LE but is slightly less specific.

Performance of the dipstick screening test as a predictor of negative urine culture.

OBJECTIVE: To investigate whether the urine dipstick screening test can be used to predict urine culture results. METHODS: A retrospective study conducted between January and December 2014 based on data from 8,587 patients with a medical order for urine dipstick test, urine sediment analysis and urine culture. Sensitivity, specificity, positive and negative predictive values were determined and ROC curve analysis was performed. RESULTS: The percentage of positive cultures was 17.5%. Nitrite had 28% sensitivity and 99% specificity, with positive and negative predictive values of 89% and 87%, respectively. Leukocyte esterase had 79% sensitivity and 84% specificity, with positive and negative predictive values of 51% and 95%, respectively. The combination of positive nitrite or positive leukocyte esterase tests had 85% sensitivity and 84% specificity, with positive and negative predictive values of 53% and 96%, respectively. Positive urinary sediment (more than ten leukocytes per microliter) had 92% sensitivity and 71% specificity, with positive and negative predictive values of 40% and 98%, respectively. The combination of nitrite positive test and positive urinary sediment had 82% sensitivity and 99% specificity, with positive and negative predictive values of 91% and 98%, respectively. The combination of nitrite or leukocyte esterase positive tests and positive urinary sediment had the highest sensitivity (94%) and specificity (84%), with positive and negative predictive values of 58% and 99%, respectively. Based on ROC curve analysis, the best indicator of positive urine culture was the combination of positives leukocyte esterase or nitrite tests and positive urinary sediment, followed by positives leukocyte and nitrite tests, positive urinary sediment alone, positive leukocyte esterase test alone, positive nitrite test alone and finally association of positives nitrite and urinary sediment (AUC: 0.845, 0.844, 0.817, 0.814, 0.635 and 0.626, respectively). CONCLUSION: A negative urine culture can be predicted by negative dipstick test results. Therefore, this test may be a reliable predictor of negative urine culture. OBJETIVO: Verificar se a triagem de urina por fitas reativas é capaz de predizer a cultura de urina. Métodos Estudo retrospectivo realizado entre janeiro e dezembro de 2014 com 8.587 pacientes, com solicitação médica de triagem de urina (fita), sedimento urinário e cultura de urina. FORAM ANALISADOS: sensibilidade, especificidade, valor preditivo positivo, valor preditivo negativo e curva ROC. RESULTADOS: Foram positivas 17,5% das culturas. O nitrito apresentou sensibilidade de 28% e especificidade de 99%. O valor preditivo positivo foi de 89% e o valor preditivo negativo de 87%. Esterase apresentou sensibilidade de 79% e especificidade de 84%. Valor preditivo positivo e valor preditivo negativo foram de 51% e 95%, respectivamente. A combinação de nitrito ou esterase positivos apresentou sensibilidade de 85% e especificidade de 84%. Valor preditivo positivo e valor preditivo negativo foram, respectivamente, 53% e 96%. O sedimento positivo (mais de dez leucócitos por microlitro) apresentou sensibilidade de 92% e especificidade de 71%. O valor preditivo positivo foi 40% e o negativo, 98%. A combinação de nitrito e sedimento urinário positivos apresentou sensibilidade de 82% e especificidade de 99%. Os valores preditivos positivo e negativo foram 91% e 98%, respectivamente. Para o nitrito ou esterase positivos mais os leucócitos positivos, a sensibilidade foi de 94% e a especificidade de 84%. O valor preditivo positivo foi de 58% e o negativo foi de 99%. Com base na curva ROC, o melhor indicador de urocultura positiva foi a associação entre a esterase ou nitrito positivos na fita mais os leucócitos positivos no sedimento, seguido por nitrito e esterase positivos, sedimento urinário positivo isolado, esterase positiva isolada, nitrito positivo isolado e, finalmente, pela associação entre nitrito e sedimento urinário positivos (AUC: 0,845, 0,844, 0,817, 0,814, 0,635 e 0,626, respectivamente). CONCLUSÃO: Uma urocultura negativa pode ser prevista com resultados negativos na fita. Portanto, este teste pode ser um preditor confiável de urocultura negativa.

Performance of the dipstick screening test as a predictor of negative urine culture / Desempenho da fita de urina como resultado presuntivo para cultura de urina negativa

ABSTRACT Objective To investigate whether the urine dipstick screening test can be used to predict urine culture results. Methods A retrospective study conducted between January and December 2014 based on data from 8,587 patients with a medical order for urine dipstick test, urine sediment analysis and urine culture. Sensitivity, specificity, positive and negative predictive values were determined and ROC curve analysis was performed. Results The percentage of positive cultures was 17.5%. Nitrite had 28% sensitivity and 99% specificity, with positive and negative predictive values of 89% and 87%, respectively. Leukocyte esterase had 79% sensitivity and 84% specificity, with positive and negative predictive values of 51% and 95%, respectively. The combination of positive nitrite or positive leukocyte esterase tests had 85% sensitivity and 84% specificity, with positive and negative predictive values of 53% and 96%, respectively. Positive urinary sediment (more than ten leukocytes per microliter) had 92% sensitivity and 71% specificity, with positive and negative predictive values of 40% and 98%, respectively. The combination of nitrite positive test and positive urinary sediment had 82% sensitivity and 99% specificity, with positive and negative predictive values of 91% and 98%, respectively. The combination of nitrite or leukocyte esterase positive tests and positive urinary sediment had the highest sensitivity (94%) and specificity (84%), with positive and negative predictive values of 58% and 99%, respectively. Based on ROC curve analysis, the best indicator of positive urine culture was the combination of positives leukocyte esterase or nitrite tests and positive urinary sediment, followed by positives leukocyte and nitrite tests, positive urinary sediment alone, positive leukocyte esterase test alone, positive nitrite test alone and finally association of positives nitrite and urinary sediment (AUC: 0.845, 0.844, 0.817, 0.814, 0.635 and 0.626, respectively). Conclusion A negative urine culture can be predicted by negative dipstick test results. Therefore, this test may be a reliable predictor of negative urine culture.

RESUMO Objetivo Verificar se a triagem de urina por fitas reativas é capaz de predizer a cultura de urina. Métodos Estudo retrospectivo realizado entre janeiro e dezembro de 2014 com 8.587 pacientes, com solicitação médica de triagem de urina (fita), sedimento urinário e cultura de urina. Foram analisados sensibilidade, especificidade, valor preditivo positivo, valor preditivo negativo e curva ROC. Resultados Foram positivas 17,5% das culturas. O nitrito apresentou sensibilidade de 28% e especificidade de 99%. O valor preditivo positivo foi de 89% e o valor preditivo negativo de 87%. Esterase apresentou sensibilidade de 79% e especificidade de 84%. Valor preditivo positivo e valor preditivo negativo foram de 51% e 95%, respectivamente. A combinação de nitrito ou esterase positivos apresentou sensibilidade de 85% e especificidade de 84%. Valor preditivo positivo e valor preditivo negativo foram, respectivamente, 53% e 96%. O sedimento positivo (mais de dez leucócitos por microlitro) apresentou sensibilidade de 92% e especificidade de 71%. O valor preditivo positivo foi 40% e o negativo, 98%. A combinação de nitrito e sedimento urinário positivos apresentou sensibilidade de 82% e especificidade de 99%. Os valores preditivos positivo e negativo foram 91% e 98%, respectivamente. Para o nitrito ou esterase positivos mais os leucócitos positivos, a sensibilidade foi de 94% e a especificidade de 84%. O valor preditivo positivo foi de 58% e o negativo foi de 99%. Com base na curva ROC, o melhor indicador de urocultura positiva foi a associação entre a esterase ou nitrito positivos na fita mais os leucócitos positivos no sedimento, seguido por nitrito e esterase positivos, sedimento urinário positivo isolado, esterase positiva isolada, nitrito positivo isolado e, finalmente, pela associação entre nitrito e sedimento urinário positivos (AUC: 0,845, 0,844, 0,817, 0,814, 0,635 e 0,626, respectivamente). Conclusão Uma urocultura negativa pode ser prevista com resultados negativos na fita. Portanto, este teste pode ser um preditor confiável de urocultura negativa.

A head-to-head comparison: "clean-void" bag versus catheter urinalysis in the diagnosis of urinary tract infection in young children.

OBJECTIVE: To compare the validity of the urinalysis on clean-voided bag versus catheter urine specimens using the catheter culture as the "gold" standard. STUDY DESIGN: This is a cross-sectional study of 303 nontoilet-trained children under age 3 years at risk for urinary tract infection (UTI) who presented to a children's hospital emergency department. Paired bag and catheter specimens were obtained from each child and sent for dipstick and microscopic urinalysis. Sensitivity and specificity were compared using McNemar's chi2 test for paired specimens and the ordinary chi2 test for unpaired comparisons. RESULTS: The bag dipstick was more sensitive than the catheter dipstick for the entire study sample: 0.85 (95% confidence interval [CI]=0.78 to 0.93) versus 0.71 (95% CI=0.61 to 0.81), respectively. Both bag and catheter dipstick sensitivities were lower in infants < or =90 days old (0.69 [95% CI=0.44 to 0.94] and 0.46 [95% CI=0.19 to 0.73], respectively) than in infants >90 days old (0.88 [95% CI=0.81 to 0.96] and 0.75 [95% CI=0.65 to 0.86], respectively). Specificity was consistently lower for the bag specimens than for the catheter specimens: 0.62 (95% CI=0.56 to 0.69) versus 0.97 (95% CI=0.95 to 0.99), respectively. CONCLUSIONS: Urine collection methods alter the diagnostic validity of urinalysis. These differences have important implications for the diagnostic and therapeutic management of children with suspected UTI.

Descriptive urological record of chimpanzees (Pan troglodytes) in the wild and limitations associated with using multi-reagent dipstick test strips.

Ten urine chemistry parameters were measured on 74 voided urine samples from 34 wild chimpanzees (Pan troglodytes). Multi-reagent urine dipstick tests were performed and results determined using colorimetric scales. Urine pH measured between 8 and 9 units in 91% of the chimpanzees. Test pads detected protein, erythrocytes, leukocyte esterase activity, and nitrites, ketones and bilirubin in 47, 32, 29, and <10% of the chimpanzees, respectively. No apparent association between positive test results for blood in adult females and reproductive status was found. Overall, 17 of the 34 chimpanzees had positive urine test results for protein, hemoglobin, erythrocytes, leukocytes, nitrites, ketones, and/or bilirubin. Dipstick urinalysis alone is an unreliable method for assessing health and physiological status of wild chimpanzees. However, if combined with other diagnostics it could prove to be a valuable health-monitoring tool. Limitations associated with this methodology need to be considered when interpreting urinary dipstick test results.

Pattern of sexually transmitted diseases among pregnant women in Burkina Faso, west Africa: potential for a clinical management based on simple approaches.

OBJECTIVES: (1) To determine the prevalence of sexually transmitted diseases (STDs) in pregnant women in Burkina Faso. (2) To evaluate the potential of clinical management of STDs based on screening with clinical data and urine leucocyte esterase test (LET). METHODS: Cross sectional study among antenatal clinic attendees was conducted in 1994 in Ouagadougou and Bobo-Dioulasso, the two largest urban centres in Burkina Faso, where more than 94% of the pregnant women benefit from antenatal care at least twice during their pregnancy. Each woman selected underwent an interview, general and gynaecological examination. Genital samples were collected to confirm the presence of STD pathogens. Logistic regression analysis was done to identify models that predict (a) gonorrhoea and/or chlamydia, (b) trichomoniasis and/or bacterial vaginosis, (c) candidiasis. Sensitivity, specificity and positive and negative predictive values of these models were assessed using standard methods. RESULTS: All 645 consecutive pregnant women were enrolled in the two sites. Among these women 32.4% presented at least one STD. The major STDs were: trichomoniasis (14%), bacterial vaginosis (13%), recent syphilis (3.6%), chlamydial infection (3.1%), genital warts (3%), gonococcal infection (1.6%) and genital ulcer (0.8%). Prevalence of vaginal candidiasis was 14%. The use of a risk marker (length of relationship with regular sexual partner < 3 years), and the positivity +3 of the urine LET provided a sensitivity of 80% and a positive predictive value of 7% for the screening of gonococcal and/or chlamydial infection. If clinical signs and positivity of the urine LET were taken into account sensitivity and positive predictive value of trichomoniasis and/or bacterial vaginosis screening were 77% and 37%, respectively. Clinical signs and positivity of the urine LET showed a low sensitivity (23%) for screening vaginal candidiasis. CONCLUSIONS: The prevalence of STDs in pregnant women is high in urban Burkina Faso. Systematic screening combined with effective treatment should be included in antenatal care in the future. Urine LET, if associated with interview and clinical examination offers a simple, rapid and affordable tool for systematic screening of STDs in pregnant women. However, the proportion of overtreatments with proposed strategies will be high. Further studies are needed to develop and validate better algorithms with probably cheap laboratory tests.

Pyuria among chronically incontinent but otherwise asymptomatic nursing home residents.

OBJECTIVE: To determine the prevalence of pyuria and its relationship to bacteriuria in a representative sample of chronically incontinent nursing home residents. DESIGN: Prospective, descriptive case series. SETTING: Six nursing homes. PARTICIPANTS: Two hundred fourteen chronically incontinent, but otherwise asymptomatic, nursing home residents who were enrolled in a clinical intervention trial for urinary incontinence. MEASURES: Two hundred fourteen urine specimens were collected by a validated clean catch technique. Each specimen underwent dipstick testing for leukocyte esterase, microscopic urinalysis to determine the number of white blood cells per high power field of centrifuged urine, and quantitative urine culture using standard laboratory techniques. RESULTS: The overall prevalence of pyuria was 45%, as defined by > 10 white blood cells per high field of spun urine, and the overall prevalence of bacteriuria was 43%, as defined by the growth of > 100,000 colony forming units of a urinary pathogen. Fifty-nine percent of the specimens with bacteriuria and 34% of the specimens without bacteriuria had pyuria. Of specimens with pyuria, 56% had bacteriuria, and of specimens without pyuria, 31% had bacteriuria. When any colon change on the leukocyte esterase pad was considered positive, this finding had a sensitivity of 83% and a specificity of 52% for pyuria on microscopic urinalysis. CONCLUSIONS: Pyuria is common among chronically incontinent nursing home residents, both in the presence and absence of bacteriuria. Clinicians must therefore be cautious in interpreting the presence of pyuria to indicate symptomatic infection in this population. Using pyuria to determine the need for antimicrobial treatment could result in unnecessary expense and morbidity as well as contribute to the development of resistant organisms in nursing homes. Research is needed to define pyuria better, to determine its prevalence and relationship to bacteriuria among nursing home residents with symptoms of acute urinary tract infection, and to elucidate the etiology and significance of sterile pyuria in this population.

Is urine leukocyte esterase test a useful screening method to predict Chlamydia trachomatis infection in women?

We evaluated the use of the leukocyte esterase test (LET) on first-catch urine specimens from women as a screening test to predict infection with Chlamydia trachomatis. For diagnosis, we used Abbott's ligase chain reaction (LCR) on urine specimens and isolation by tissue culture (TC) on cervical brushes. Of 4,053 women attending sexually transmitted disease and family planning clinics, 4.3% (n = 174) were positive by TC and 5.9% (n = 239) were positive by LCR. When LET was compared to TC, the sensitivity, specificity, positive predictive value, and negative predictive value were 54.0, 67.0, 6.8, and 97.0%, respectively. The corresponding performance of LET versus LCR was 53.1, 67.3, 10.1, and 95.8%. Almost half of the laboratory-confirmed chlamydial infections were negative by LET. The low specificity probably reflects multiple causes of pyuria in women and results in a low positive predictive value. LET is neither sensitive nor specific as a predictor of chlamydial infection and cannot be recommended for use as a screening test for C. trachomatis with first-catch urine samples from females from low- or moderate-prevalence populations.

Rapid dipstick test for diagnosis of urinary tract infection.

The rapid dipstick test of urine leukocyte esterase (LE) activity and nitrite has not been studied fully in pediatric clinical situations. We investigated the usefulness of the dipstick LE and nitrite test in the screening of urinary tract infection (UTI) in pediatric patients. Ninety-two fresh urine samples were obtained from children suspected of having UTI. Leukocyte esterase activity and nitrite were measured in the urine specimens read by a photometer. Leukocytes were also counted on a disposable slide. Urine samples were examined for bacteriuria by the standard culture method. The results of the urine dipstick test of LE showed a close relationship with leukocyte counts on a counting chamber. Leukocyte esterase (-) indicated leukocyte counts of less than 10/uL with a probability of 97% (58/60). Of the 22 urine samples with significant bacteriuria diagnosed by standard urine culture, the nitrite test did not detect bacteriuria in 10. While the sensitivities of the dipstick tests of nitrite (+) and LE +/- or more for the diagnosis of significant bacteriuria were 55% (12/22) and 86% (19/22), respectively, the sensitivity and negative predictive value of the combined test were 100%. These results suggest that use of the dipstick test of LE and nitrite can avoid a large part of the cost incurred by urine culture and is useful for screening UTI in children.

A reassessment of the importance of "low-count" bacteriuria in young women with acute urinary symptoms.

OBJECTIVE: To determine whether a statistical association exists between "low-count" bacteriuria (> 10(2) to 10(4) colony-forming units/mL) and acute urinary symptoms in young women. DESIGN: Prospective, case-control study. SETTING: Gynecology clinic at a student health center. PATIENTS: Women with or without urinary or vaginal symptoms. MEASUREMENTS: History of urinary infections and sexual activity. Quantitative determination of bacteriuria and pyuria and bacterial species; urine leukocyte esterase test; specific gravity; creatinine levels; vaginal leukocytes; and in-vitro culture of urine. RESULTS: The frequency of recent sexual activity, pregnancies, and contraceptive practices was not statistically different between women with acute urinary symptoms and asymptomatic controls. Escherichia coli and Staphylococcus saprophyticus were the only microorganisms statistically associated with urinary symptoms and pyuria (P < 0.001). Low counts of these organisms were found in 10.2% of asymptomatic women. As the bacterial count increased, the association between these organisms and symptoms increased, and a step-wise increase occurred in the frequency and magnitude of pyuria, but the specific gravity and urine creatinine levels remained unchanged. Escherichia coli, even at low counts, grew well in the patients' own urine. Pyuria (> 20 leukocytes/mm3) was present in 19.6% of asymptomatic women and was associated with vaginal leukorrhea. CONCLUSIONS: "Low-count" bacteriuria was statistically more frequent among young women with urinary symptoms than among asymptomatic controls. The low counts could not be explained by dilution of the urine or failure of the bacteria to grow well in the patients' urine. These findings suggest that the infection was not established in the bladder urine and that "low-count" bacteriuria might be an early phase of urinary tract infection.

[The validation of a rapid diagnostic method for urinary infection in the school-age population]. / Validación de un método de diagnóstico rápido de infección urinaria en población escolar.

Validity of visual reading of a reactive strip is measured, in comparison with automatized reading and the exam of the urinary sediment, in 562 school pupils with ages between 6 and 16 years. Using urine culture as standard reference, sensibility of the leukocyte-esterase (L-E) test, nitrites and red cells was 66.7%, 33.3% and 66.7% respectively, for the visual reading; 66.7%, 33.3% and 33.3% for automatized reading, respectively; and 66.7% for leukocyturia, and 33.3% for hematuria in the urine sediment. Specificity of tests was 84.9%, 99% and 42.7% for L-E, nitrites and red cells, in visual reading; 92.5%, 100% and 80.8% for the same tests in automatized reading, and 94.5% (leukocyturia) and 86.3% (red cells) in the urinary sediment. Validity of these diagnostic methods results different depending on the population they are applied to. Even though the multi-urine test is still the most effective test in a symptomatic population and the less expensive, it would be not recommendable its use as a screening test in a school population with hidden urinary infection.

Two rapid urine screens for detection of bacteriuria: an evaluation.

Five hundred twenty-five random clean catch urine specimens, collected from 339 adult females, 137 adult males, and 49 pediatric patients, were screened for the presence of bacteriuria with the Uriscreen catalase test and with the Chemstrip 2 LN dipstick. Quantitative cultures were performed on all specimens. The sensitivity, specificity, positive predictive value, and negative predictive value for the catalase test, with 10(5) CFU/ml as the threshold for significant bacteriuria, were 91.3%, 72.3%, 33.7%, and 98.0%, respectively. Values for the dipstick were 83.9%, 77.9%, 43.7%, and 96.0%. When 10(4) CFU/ml was used as the threshold, the catalase test had a sensitivity of 89.2%, specificity of 70.4%, positive predictive value of 37.3%, and a negative predictive value of 97.0%. Values for the dipstick at that level were 82.3%, 77.5%, 48.6%, and 94.8%. While the catalase test was more sensitive than the dipstick, it was our opinion that high rates of false-negatives associated with these methods negated the convenience of these fast and simple urine screens.

[Information value of clinical signs and stat tests as indicators of female outpatient urinary tract infection].

This study was designed to evaluate signs and stat tests as an indicator of lower urinary tract infection in female subjects with urogenital complaints at an out-patient clinic. Of various symptoms including hematuria, pollakiuria, dysuria, urinary retention, and micturition pain, pain during micturition was present in 48% of 25 patients with urinary tract infections and in 4% of 27 patients without urinary tract infections, and was the sign with the highest positive predictive value. Comparison and discrimination of the infection and non-infection groups using a single laboratory valuable yielded significant F-statistics for urinary leukocyte esterase (14.5) and leukocyte count in urinary sediment (31.1), and revealed large Mahalanobis' distances for the same variables. Multivariate analysis using a discriminant function of categorical data (Hayashi's Suryoka type 2) revealed that combining occult blood with leukocyte esterase in the urine or combining red cell count with leukocyte count in sediment did not yield substantially smaller misclassification error than did leukocyte esterase alone or leukocyte count alone. It was concluded that neither urinary occult blood nor red cell count in sediment contribute substantially to the prediction of urinary tract infection. For the purpose of detecting urinary tract infection among outpatients, a receiver-operating characteristic analysis demonstrated that the optimal cut-off point in sediment was 3 or more leukocytes per microscopic high power field (x 400). Urinary leukocyte esterase was found to have limitations for use in screening, because its optimal decision level is equivalent to trace esterase reading on the dipstick test.

[Usefulness of dipstick test for determining leukocytes and bacteria in urine].

The value of a simple dipstick test (BMtestLN, Boehringer Mannheim-Shionogi) for determination of leukocytes and bacteria in urine was examined. This test consisted of detection of esterase, an enzyme present in leukocytes and the nitrate reduced by bacteria. A total of 666 clinical urine specimens were tested with both tests. The evaluation of leukocytes in urine was compared with microscopic examination, and the identification and measurement of strains was performed using a semiquantitative plate culture method as a reference. The leukocyte esterase test had a sensitivity of 85.3%, a specificity of 67.3%, positive predictive value of 54.7% and negative predictive value of 90.8%. The range of the sensitivity value of nitrate test was 25.7% for the detection of bacteriuria (bacteria greater than or equal to 10(4) CFU/ml). This test had a specificity of 99.6%, positive predictive value of 94.8% and negative value of 82.9%. We concluded that this dipstick test is not useful for determination of the slight change of pyuria, but sensitive for the determination of acute and untreated urinary tract infections.

Renal alteration and development of hypertension in diabetic rats.

UNLABELLED: There is a close association between diabetes and hypertension. Many studies have demonstrated an increased incidence of hypertension in the presence of diabetic nephropathy. The aim of the present work was to study the kallikrein-kinin system during the diabetic states with hypertension. In this study neonatal rats were injected with streptozotocin at two days of age. Plasma glucose, proteinuria, urinary kallikrein, blood pressure, creatinine clearance, diuresis and body weight were measured. RESULTS: control rats vs diabetic rats. Plasma glucose (mg/dl): 0 minutes 80.2 +/- 2.5 vs 105.5 +/- 4.5; 60 minutes 120.4 +/- 2.3 vs 220.0 +/- 4.6; 120 minutes 105.0 +/- 1.5 vs 140.0 +/- 3.6; p < 0.05. Proteinuria at 8 months of age (mg/24 hs): 12.5 +/- 1.6 vs 20.6 +/- 2.4; p < 0.05. Urinary kallikrein at 8 months of age (umol/min/24 hs)/(ml/min) x 10(3): 46.9 +/- 3.0 vs 28.5 +/- 2.5; p 0.005. Blood pressure at 8 months of age (mm Hg): 110.0 +/- 2.0 vs 132.0 +/- 4.0; p < 0.001. Creatinine clearance at 10 months of age (ml/min): 0.46 +/- 0.03 vs 0.70 +/- 0.14; p < 0.05. Diuresis at 8 months of age (ml/24 hs): 1.55 +/- 0.65 vs 10.30 +/- 1.44, p < 0.001. The early modifications of kallikrein-kinin system in the diabetes states may contribute to development hypertension with modifications in the hemodynamics renal function.

Use of a urine enzyme immunoassay as a diagnostic tool for Chlamydia trachomatis urethritis in men.

We collected first-voided urine specimens from 659 males attending a sexually transmitted disease clinic and performed both enzyme immunoassay (EIA) for detection of chlamydial antigen and leukocyte esterase testing on these urine samples. The overall prevalence of chlamydial urethritis in the study population as determined by culture of urethral swabs was 11%. However, 46% of all men in the study had no symptoms of urethritis. Compared with urethral cultures for chlamydiae, the urine EIA had a sensitivity of 42% and a specificity of 99%. The sensitivity of the EIA strongly correlated with the amount of antigen present in culture as assessed by numbers of inclusion-forming units. The sensitivity of the leukocyte esterase test compared with that of chlamydia culture was 88%. We conclude that in this population of men, which included many patients without symptoms of urethritis, the urine EIA was a relatively insensitive means of screening for chlamydial infection.

Screening for Chlamydia trachomatis in adolescent males: a cost-based decision analysis.

To evaluate the cost and benefits of screening tests for Chlamydia trachomatis in adolescent males, we developed a decision analysis model and compared the leukocyte esterase urine dipstick test with culture, with direct-smear fluorescent antibody (DFA), and with the option of no screening (no treatment). The leukocyte esterase test has the lowest average cost-per-cure ($51) compared with direct-smear fluorescent antibody ($192) and culture ($414). Compared with the DFA, we estimate that the leukocyte esterase test saves over $9,727 per cohort of 1,000 sexually active adolescent males screened. Sensitivity analyses show the leukocyte esterase test results in a lower cost-per-cure and lower overall costs (per cohort) than culture and direct-smear fluorescent antibody at any prevalence of C. trachomatis infection, and lower overall costs (per cohort) than no screening at prevalences above 21 percent.