Presence Of Leukocyte Esterase Research Articles

Evaluation of the diagnostic accuracy of lower urinary tract symptoms (LUTS) in uncomplicated UTI in Pakistani women

Objective: To evaluate the diagnostic accuracy of lower urinary tract symptoms in uncomplicated urinary tract infection in women. Method: The cross-sectional study was conducted from September 2020 to December 2021 after approval from the ethics review board of Jinnah Postgraduate Medical Centre, Karachi, and comprised data of women aged at least 16 years from 8 institutions across Pakistan. Data included menstruation status, symptoms, urinalysis and organisms found in urine samples. The association of urinalysis variables with symptoms among culture-positive patients was measured to assess the certainty of positive diagnosis. Data was analysed using SPSS 23. Results: Of the 457 women with mean age 37.87±13.9 years, 182(39.8%) had a positive urine culture. Dysuria was the most significant symptom 120(65.9%), followed by daytime frequency 114(62.6%) amongst culture-positive patients. On urinalysis, 139(76.3%) had white blood cells, and 66(36.2%) had haematuria. Dysuria along with the presence of leucocyte esterase had the highest diagnostic utility (p=0.002). Urgency along with haematuria was strongly predictive of urinary tract infection (p=0.058). Conclusion: The diagnosis of uncomplicated urinary tract infection in women could be reliably made based on a combination of symptoms along with urine analysis without urine culture. Key Words: Urinary tract infection, Lower urinary tract symptoms, Urinalysis; Urine culture.

Uropathogens and their antibiotic susceptibility patterns among diabetic patients at st. john of god hospital, duayaw nkwanta, Ghana: a cross-sectional study.

Uropathogens are microorganisms that cause urinary tract infections (UTIs). Owing to higher blood glucose levels and compromised immune functions, treatment of uropathogens in diabetic patients is a challenge. This study aims to assess the prevalence of uropathogens and their antibiotic susceptibility among diabetic patients at St. John of God Hospital at Duayaw Nkwanta (SJGHDN) in the Ahafo region of Ghana. The cross-sectional study recruited 175 diabetic patients at SJGHDN between August and September 2023. Questionnaires were used to collect patients' background information. Fasting Blood Sugar (FBS) was assessed by using a glucometer. Urine samples were examined for the presence of uropathogens. A sterile inoculating loop with a calibrated volume of 2 µl was used for plating. Each colony equals 500 CFU/mL. Significant uropathogen was determined by multiplying the counted colonies by 500 to obtain CFU/mL. Positive uropathogen was defined as CFU ≥ 105/mL. Significant uropathogen was defined as ≥200 colonies per sample. The disc diffusion method was used to determine antibiotic susceptibility. Out of the 175 patients, 19.4% expressed various uropathogens with Escherichia coli being the predominant. Suboptimal glucose level was the most significant risk factor (p = 0.038). Glucosuria (p = 0.036), hazy urine (p = 0.028), positive leukocyte esterase (p = 0.001), and pus cells in urine sediment (p = 0.020) were significant indicators of uropathogen occurrence. Klebsiella pneumonia and Proteus mirabilis were resistant to ≥4 antibiotics. Amikacin, nitrofurantoin, levofloxacin, ciprofloxacin, and ceftriaxone demonstrated efficacy against the isolates. This study underscores the notable prevalence of uropathogens in diabetic patients and the alarming levels of antibiotic resistance observed. The results highlight the critical need for vigilant monitoring and customized treatment approaches, particularly for diabetic patients exhibiting risk factors such as elevated urine glucose levels, cloudy urine, and presence of leukocyte esterase and pus cells in urine sediment. The significant resistance to frequently used antibiotics like co-trimoxazole and tetracycline points to the necessity of routine susceptibility testing and the use of alternative antibiotics for effective treatment. These findings can assist healthcare providers in more effectively managing and preventing UTIs in diabetic populations.

147. Opportunities for Improving Urine Culturing Practices in U.S. Acute Care Hospitals, 2017-2020

Abstract Background Inappropriate urine cultures (UCs) lead to misdiagnosis and unnecessary antibiotic use and can impact surveillance. The absence of pyuria on a urinalysis (UA) has a high negative predictive value for urinary tract infections (UTIs) in certain settings and can reduce unnecessary UCs. UCs performed without UA or with a negative UA indicate opportunities for diagnostic stewardship. Understanding facility variability and patient characteristics associated with inappropriate UCs can inform improvements in acute care hospitals (ACHs). Methods Using clinical microbiology data from 279 ACHs reporting UC and UA data to the PINC AI Healthcare Database, we assessed appropriateness of the first UC collected during adult hospitalizations, excluding pregnant and urologic procedure patients identified using ICD-10-CM diagnosis codes. Each UC was categorized as follows: (1) UC with at least 1 positive UA (WBC ≥10/HPF, presence of leukocyte esterase or nitrite) 24 hours before/after UC (UA+ UC), (2) UC with negative UA in 24 hours (UA- UC), and (3) UC without UA in 24 hours (no-UA UC). Overall percentages of UC categories were described by year and patient characteristics. Monthly facility-specific percentages of UCs were calculated, and facility-level variability was described by medians, quartiles 1 and 3 (Q1:Q3). Results 1.2 million incident UCs were included. Of those, 65% were UA+, 21% UA-, and 14% no-UA UCs. From 2017 to 2020, UA+ UCs increased from 60.5% to 68.2%, no-UA UCs decreased from 19.3% to 10.5%, and UA- UCs stayed at 21%. UA- and no-UA UCs were more common among male, younger age, and Medicaid patients (Figure 1). No-UA UCs were more commonly obtained on day 4 or later. The median monthly facility-level percentages of UA+, UA-, no-UA UCs were 75 (Q1:Q3, 55.6-86.5), 15 (Q1:Q3, 6.5-28.6), and 5.3 (Q1:Q3, 2.1-10.5), respectively (Figure 2). Overall Percentages of Urine Cultures Variability in Hospital Monthly Percentages of Urine Cultures (UC) in Each Category, 2017-2020, N hospital-months = 9,863 Hospital-level Variability Conclusion During the study period, urine culturing practices improved; however, 35% of incident UCs had no UA or negative UA. The high proportion of these UCs and facility-level variability of the monthly proportions call for diagnostic stewardship to identify and address causes of the potentially suboptimal UC practices. This will support the efforts to decrease UTI overdiagnosis and antibiotic overuse. Disclosures All Authors: No reported disclosures

Diabetic strips as coulometric sensors for hydroquinone and leukocyte esterase

Abstract The activity of leukocyte esterase (LE) is a proxy for the presence of leukocytes in the diagnosis of infection, a common cause of patient morbidity and mortality. Here, the ability of commercial glucose test strips to detect hydroquinone (HQ) down to 1.0 μM was explored for the determination of LE in human synovial (joint) fluid and urine samples. To this end, the HQ-releasing substrate (HQS) for LE was synthesized and tested by chronocoulometry at a glucose strip linked to a laboratory potentiostat. The latter was used, rather than a glucometer, to improve the limit of detection. In the presence of LE in a sample, the HQS discharged HQ that was detected at a glucose strip covering a clinically relevant range from 20 μg L−1 (0.64 nM) to 750 μg L−1 LE (R2, 0.973, N = 8). Such a coulometric assay was selective with respect to human LE and required a 20-min sample incubation with HQS, which is much shorter than the current hours-long immunoassays for LE. The assay relied on a differential signal, which circumvented the interferences including those from endogenous glucose and provided a direct measure of infection regardless of the complexity of sample matrix. The scaled-up synthesis of HQS along with the wide availability of glucose strips provides a prospect for the commercialization of such an infection assay.

Determining the degree of accuracy of Combar-10 reagent strip in diagnosing bacterial meningitis

Background: The gold standard for diagnosis of meningitis depends on cerebrospinal fluid (CSF) examination by microscopy, biochemistry, and culture, which require experienced personnel and laboratory support. We conducted this study to determine if urinary reagent strip is useful to make a semi-quantitative assessment of protein, glucose, and presence of leukocyte esterase in CSF.Methods: All consecutive CSF samples were evaluated in a blinded fashion. CSF was tested using Combur-10 urinary reagent strip as an index test, and CSF microscopy and biochemistry as reference standards. Combur-10 (Boehringer Mannheim) is an urinary reagent strip used to estimate ten parameters including protein, glucose, and leukocytes. We estimated diagnostic accuracy of each index test using corresponding cut-off levels (glucose <1 + vs. CSF glucose <50 mg/dL; protein 2 + and 3 + vs. CSF protein >30 mg/dL and >100 mg/dL; leukocyte esterase positivity vs. >10 granulocytes in CSF sample). We constructed receiver operating curves (ROC) to evaluate overall performance of index tests and estimated area under the curve (AUC).Results: CSF samples of 150 patients were included in the study. Of the three tests, diagnostic accuracy of protein estimation (2+ or more on reagent strip) was best for detection of CSF proteins greater than 50 mg/dL [sensitivity 93.2% (95% CI 86.63-96.67); specificity 91.49% (95% CI 80.07, 96.64)], with AUC of 0.97. Leukocyte esterase positivity by test strip had a sensitivity of 90% (95% CI 82.08, 94.65) and specificity of 91.6% (95% CI 81.93, 96.39) for detection of CSF granulocytes of more than 10/mm3.Conclusions: The degree of accuracy of Combar-10 reagent strip in diagnosing bacterial meningitis is very high similar to CSF microscopy and biochemistry.

Diagnosis and Antibiotic Resistance Distribution in Children with Urinary Tract Infection: A Single Center Experience

Background: Urinary tract infection is a common disease in childhood. The aim of this study was to determine the diagnostic performance of urinary analysis, assess the role of urine culture in determining its necessity and evaluate etiologic agents and antimicrobial resistance patterns in children with urinary tract infection.Methods: Our study was made by evaluating the patients who applied to the Antalya Research and Training Hospital- Turkey, between 2015 and 2017. A total 237 urine analysis and urine culture were retrospectively analyzed. Culture results were taken a reference for microscopic and chemical examination of urine and diagnostic accuracy of the test parameters, and the performance of urine analysis were calculated. The culture and antibiogram results were examined and antibiotic resistance with infectious agents frequency was evaluated.Results: The 42.4% of culture negative samples showed leukocyte esterase, nitrite, bacterial and leukocyte counts, which are indicative of infection in urine analysis, were found in normal range. The highest sensitivity (90%) was in the presence of leucocyte esterase and bacteria, while the highest specificity (99.4%) was in the presence of nitrite alone or with other components (leucocyte or leucocyte esterase). The highest antibiotic resistance was found in beta lactam antibiotics. The lowest antibiotic resistance was detected in the carbapenem followed by fluoroquinolone group antibiotics.Conclusion: Microscopic and chemical examination of urine analysis can give us information about urine culture requirement. The observation of increasing overall resistance to antibiotics authorize further studies that lead to new recommendations to antibiotic use in children and adolescents.

Are Urinalyses Used Inappropriately in the Diagnosis of Urinary Tract Infections?

BackgroundOne of the most readily available and cost effective tests in the diagnosis of urinary tract infections (UTI) is the urinalysis. Problems arise when antibiotic treatment is initiated in a patient who does not display typical signs and symptoms of UTI and for whom a urinalysis was obtained for other reasons.MethodsThis was a retrospective observational study carried out on 1000 patients with positive urine nitrite. Medical records were identified with subsequent analysis of urine culture and symptomatology. Recorded and analyzed data included: age, sex, location (emergency room (ER) or hospital ward), findings on urinalysis (pH, presence of leukocyte esterase(LE), epithelial cells, bacteria, and white blood cells (WBCs)) and antibiotic treatment.ResultsOf these 1000 patients with positive nitrite, we excluded 815 patients (81 had missing data, 466 met exclusion criteria and 268 had symptomatic UTI). 185 were found to not have any symptoms of a UTI. Inappropriate antibiotic treatment occurred in 108/185 patients (58.4%) and was significantly associated with greater amounts of bacteria and WBCs in the urinalyses (P = 0.008 and P = 0.029, respectively). It was also significantly more likely to occur in the ER than the hospital wards (92/147 treated in the ER vs. 16/37 treated on the hospital wards, P = 0.033). There was no significant association between antibiotic treatment and age, sex, urine pH, urine LE, and urine epithelial cell amounts (P > 0.05). Urine cultures were not obtained in 69.7% of patients. A positive urine culture was significantly associated with inappropriate antibiotic treatment (P = 0.0006). The two most common presenting complaints were psychiatric complaints (21.6%) and vaginal bleeding (14.6%).ConclusionUrinalysis can be an invaluable diagnostic tool, but must be used and interpreted appropriately. There is a misperception that pyuria with bacteriuria defines UTI. However, positive results on a urinalysis alone in an asymptomatic patient is not enough to diagnose a UTI, and antibiotic treatment is only indicated in specific circumstances as outlined by IDSA guidelines for the treatment of asymptomatic bacteriuria. Further education targeting appropriate interpretation of urinalyses and IDSA guidelines is needed to decrease the unnecessary use of antibiotics.Disclosures All authors: No reported disclosures.

Urinalysis findings and urinary kidney injury biomarker concentrations

IntroductionUrinary biomarkers of kidney injury are presumed to reflect renal tubular damage. However, their concentrations may be influenced by other factors, such as hematuria or pyuria. We sought to examine what non-injury related urinalysis factors are associated with urinary biomarker levels.MethodsWe examined 714 adults who underwent cardiac surgery in the TRIBE-AKI cohort that did not experience post-operative clinical AKI (patients with serum creatinine change of ≥ 20% were excluded). We examined the association between urinalysis findings and the pre- and first post-operative urinary concentrations of 4 urinary biomarkers: neutrophil gelatinase-associated lipocalin (NGAL), interleukin-18 (IL-18), kidney injury molecule-1 (KIM-1), and liver fatty acid binding protein (L-FABP).ResultsThe presence of leukocyte esterase and nitrites on urinalysis was associated with increased urinary NGAL (R2 0.16, p < 0.001 and R2 0.07, p < 0.001, respectively) in pre-operative samples. Hematuria was associated with increased levels of all 4 biomarkers, with a much stronger association seen in post-operative samples (R2 between 0.02 and 0.21). Dipstick proteinuria concentrations correlated with levels of all 4 urinary biomarkers in pre-operative and post-operative samples (R2 between 0.113 and 0.194 in pre-operative and between 0.122 and 0.322 in post-operative samples). Adjusting the AUC of post-operative AKI for dipstick proteinuria lowered the AUC for all 4 biomarkers at the pre-operative time point and for 2 of the 4 biomarkers at the post-operative time point.ConclusionsSeveral factors available through urine dipstick testing are associated with increased urinary biomarker concentrations that are independent of clinical kidney injury. Future studies should explore the impact of these factors on the prognostic and diagnostic performance of these AKI biomarkers.

Electrochemical Substrate and Assay for Esterolytic Activity of Human White Blood Cells.

The ester 4-((tosyl-l-alanyl)oxy)phenyl tosyl-l-alaninate (TAPTA) was synthesized and tested as a substrate for leukocyte esterase (LE), an enzyme produced by leukocytes (white blood cells). In the presence of LE, TAPTA released a redox-active fragment whose oxidation at an electrode provided a direct numerical measure of LE activity. The assays showed that LE recognized TAPTA as its substrate with the Michaelis constant Km and Imax equal to 0.24 mM and 0.13 mA cm-1, respectively. The esterolytic activity of leukocyte suspensions was determined by using the internally calibrated electrochemical continuous enzyme assay (ICECEA). One activity unit (U) of LE catalyzed the hydrolysis of 1.0 μmol of TAPTA per minute in a pH 7.40 phosphate buffer saline solution containing 10% dimethyl sulfoxide (DMSO) at 21 °C. The measured units were directly proportional to the number of leukocytes in the range of 0.028-4.2 U L-1 (9-690 μg L-1 LE protein). One white blood cell displayed the average esterolytic activity of 0.86 and 1.4 nU when the ultrasonic and chemical cytolysis were used, respectively. The ICECEA is an electrochemical alternative to optical assays for the determination of LE activity as an inflammatory biomarker and proxy for the presence of leukocytes.

The Importance of Urine Concentration on the Diagnostic Performance of the Urinalysis for Pediatric Urinary Tract Infection

The presence of leukocyte esterase by urine dipstick and microscopic pyuria are both indicators of possible urinary tract infection. The effect of urine concentration on the diagnostic performance of the urinalysis for pediatric urinary tract infection has not been studied. Our objective is to determine whether the urinalysis performance for detecting urinary tract infection varies by urine concentration as measured by specific gravity. This was a retrospective cross-sectional study of the urine laboratory results of children younger than 13 years who presented to the emergency department during 68 months and had a paired urinalysis and urine culture obtained. Urinary tract infection was defined as pure growth of a uropathogen at standard culture thresholds. Test characteristics were calculated across 4 specific gravity groups (1.000 to 1.010, 1.011 to 1.020, 1.021 to 1.030, and>1.030). In total, 14,971 cases were studied. Median age was 1.5 years (interquartile range 0.4 to 5.5 years) and 60% were female patients. Prevalence of urinary tract infection was 7.7%. For the presence of leukocyte esterase and a range of pyuria cut points, the positive likelihood ratios decreased with increasing specific gravity. From most dilute to most concentrated urine, the positive likelihood ratio decreased from 12.1 (95% confidence interval [CI] 10.7 to 13.7) to 4.2 (95% CI 3.0 to 5.8) and 9.5 (95% CI 8.6 to 10.6) to 5.5 (95% CI 3.3 to 9.1) at a threshold of greater than or equal to 5 WBCs per high-power field and presence of leukocyte esterase, respectively. The negative likelihood ratios increased with increasing specific gravity for leukocyte esterase and microscopic pyuria. For the detection of pediatric urinary tract infection, the diagnostic performance of both dipstick leukocyte esterase and microscopic pyuria varies by urine concentration, and therefore the specific gravity should be considered when the urinalysis is interpreted.

Treatment for Positive Urine Cultures in Hospitalized Adults: A Survey of Prevalence and Risk Factors in 3 Medical Centers.

Antibiotic treatment for asymptomatic bacteriuria (ASB) is prevalent but often contrary to published guidelines. To evaluate risk factors for treatment of ASB. Retrospective observational study. A tertiary academic hospital, county hospital, and community hospital. Hospitalized adults with bacteriuria. Patients without documented symptoms of urinary tract infection per Infectious Diseases Society of America (IDSA) criteria were classified as ASB. We examined ASB treatment risk factors as well as broad-spectrum antibiotic usage and quantified diagnostic concordance between IDSA and National Healthcare Safety Network criteria. Among 300 patients with bacteriuria, ASB was present in 71% by IDSA criteria. By National Healthcare Safety Network criteria, 71% of patients had ASB; within-patient diagnostic concordance with IDSA was moderate (kappa, 0.52). After excluding those given antibiotics for nonurinary indications, antibiotics were given to 38% (62/164) with ASB. Factors significantly associated with ASB treatment were elevated urine white cell count (65 vs 24 white blood cells per high-powered field, P<.01), hospital identity (hospital C vs A, odds ratio, 0.34 [95% CI, 0.14-0.80], P =.01), presence of leukocyte esterase (5.48 [2.35-12.79], P<.01), presence of nitrites (2.45 [1.11-5.41], P=.03), and Escherichia coli on culture (2.4 [1.2-4.7], P=.01). Of patients treated for ASB, broad-spectrum antibiotics were used in 84%. ASB treatment was prevalent across settings and contributed to broad-spectrum antibiotic use. Associating abnormal urinalysis results with the need for antibiotic treatment regardless of symptoms may drive unnecessary antibiotic use.

Reliability of dipstick assay in predicting urinary tract infection.

Aims:Urine dipstick analysis is a quick, cheap and a useful test in predicting Urinary Tract Infection (UTI) in hospitalized patients. Our aim is to evaluate the reliability (sensitivity) of urine dipstick analysis against urine culture in the diagnosis of UTI.Materials and Methods:Patients admitted to our hospital suspected of having UTI, with positive urine cultures were included in this study from a 2-year period (January 2011 to December 2012). Dipstick urinalysis was done using multistix 10 SG (Siemens) and clinitek advantus analyzer. The sensitivity of dipstick nitrites, leukocyte esterase and blood in these culture-positive UTI patients was calculated retrospectively.Results:Urine dipstick analysis of 635 urine culture-positive patients was studied. The sensitivity of nitrite alone and leukocyte esterase alone were 23.31% and 48.5%, respectively. The sensitivity of blood alone in positive urine culture was 63.94%, which was the highest sensitivity for a single screening test. The presence of leukocyte esterase and/or blood increased the sensitivity to 72.28%. The sensitivity was found to be the highest when nitrite, leukocyte and blood were considered together.Conclusions:Nitrite test and leukocyte esterase test when used individually is not reliable to rule out UTI. Hence, symptomatic UTI patients with negative dipstick assay should be subjected to urine culture for a proper management.

Diagnostic accuracy of urinary reagent strip to determine cerebrospinal fluid chemistry and cellularity

Background:The gold standard for diagnosis of meningitis depends on cerebrospinal fluid (CSF) examination by microscopy, biochemistry, and culture, which require an experienced microscopist and laboratory support. We conducted this study to determine if urinary reagent strip is useful to make a semi-quantitative assessment of protein, glucose, and presence of leukocyte esterase in CSF.Materials and Methods:All consecutive CSF samples were evaluated in a blinded fashion. CSF was tested using Combur-10 urinary reagent strip as an index test, and CSF microscopy and biochemistry as reference standards. Combur-10 (Boehringer Mannheim) is a urinary reagent strip used to estimate ten parameters including protein, glucose, and leukocytes. We estimated diagnostic accuracy of each index test using corresponding cut-off levels (glucose 1 + vs. CSF glucose >50 mg/dL; protein 1 + and 2 + vs. CSF protein >30 mg/dL and >100 mg/dL; leukocyte esterase positivity vs. >10 granulocytes in CSF sample). We constructed receiver operating curves (ROC) to evaluate overall performance of index tests and estimated area under the curve (AUC).Results:CSF samples of 75 patients were included in the study. All the three indicator tests (CSF cells, protein, and glucose) were normal in 17 (22.6%) samples. Of the three tests, diagnostic accuracy of protein estimation (1 + or more on reagent strip) was best for detection of CSF proteins greater than 30 mg/dL [sensitivity 98.1% (95% CI 90.1-100%); specificity 57.1% (95% CI 34-78.2%)], with AUC of 0.97. Sensitivity and specificity for 2 + on reagent strip and CSF protein > 100 mg/dL were 92.6% (95% CI 75.1-99.1) and 87.5% (95% CI 74.8-95.3), respectively, with AUC of 0.96 (95% CI 0.92-1.01). Leukocyte esterase positivity by test strip had a sensitivity of 85.2 (95% CI 66.3-95.8%) and specificity of 89.6 (95% CI 77.3-96.5%) for detection of CSF granulocytes of more than 10/mm3.Conclusion:Existing urinary reagent strips can be used to diagnose meningitis in low-resource settings.

610 WHAT FACTORS CAN BETTER PREDICT THE INCIDENCE OF UROSEPSIS FOLLOWING AN ACUTE STONE EPISODE?

You have accessJournal of UrologyInfections/Inflammation of the Genitourinary Tract: Kidney & Bladder1 Apr 2010610 WHAT FACTORS CAN BETTER PREDICT THE INCIDENCE OF UROSEPSIS FOLLOWING AN ACUTE STONE EPISODE? John Mancini, Eliza Raymundo, Daniel Yong, Charles Scales, Michael Lipkin, Michael Ferrandino, Dorit Zilberman, Charles Gerardo, and Glenn Preminger John ManciniJohn Mancini More articles by this author , Eliza RaymundoEliza Raymundo More articles by this author , Daniel YongDaniel Yong More articles by this author , Charles ScalesCharles Scales More articles by this author , Michael LipkinMichael Lipkin More articles by this author , Michael FerrandinoMichael Ferrandino More articles by this author , Dorit ZilbermanDorit Zilberman More articles by this author , Charles GerardoCharles Gerardo More articles by this author , and Glenn PremingerGlenn Preminger More articles by this author View All Author Informationhttps://doi.org/10.1016/j.juro.2010.02.924AboutPDF ToolsAdd to favoritesDownload CitationsTrack CitationsPermissionsReprints ShareFacebookTwitterLinked InEmail INTRODUCTION AND OBJECTIVES Sepsis from an obstructing stone is a relatively rare, but potentially lethal consequence of ureteral stones. Little is known about specific factors which are associated with development of urosepsis in patients who are initially deemed candidates for conservative management. Our objective was to identify clinical factors associated with the development of urosepsis after an initial trial of conservative therapy. METHODS A chart review of the past 3 years identified 1,402 patients seen in the Emergency Department (ED) with urolithiasis, of which 76 were admitted to the hospital with acute symptoms. Of the remaining patients placed on conservative therapy, 9 returned to the ED with urosepsis within a two week period. Upon review of inpatient records over the past 10 years, an additional 14 patients were identified, who had been admitted with urosepsis after being discharged from the ED. For these 23 patients, a matched case-control design was used to compare the septic patients with two age, sex and race matched control subjects. Univariate analysis with logistic regression was used to determine the association of specific factors related to urosepsis: recent history of fever, temperature, white blood (WBC) count, and urinalysis variables (leukocyte esterase, and nitrite positivity). RESULTS 0.68% of patients initially treated with conservative therapy, returned to the ED in urosepsis. The median age was 47 years and the majority of patients were female (65%). The median time for return to the ED was 2 days (range 1-14). When compared to the matched control group, the median WBC count was 10.7 vs. 9.0 x 109 cells per liter (OR=1.02, CI=0.889-1.192, p=0.699). The presence of subjective fever was not significantly associated (OR=2.917, CI=0.701-12.139, p=0.141), however temperature was significantly higher in the urosepsis patients, median 37.0° vs. 36.35°C (OR=4.08, CI=1.767-9.401, p=0.001). A temperature > 37.5°C was associated with a 7-fold increase in the risk of developing urosepsis (OR=7.64, CI=1.791-32.630, p=0.006). Neither the presence of leukocyte esterase or nitrites was associated with urosepsis. CONCLUSIONS The development of urosepsis from ureteral calculi is rare. Our study suggests that several reported predictors of infection were not associated with urosepsis. However, elevated temperature, particularly greater than 37.5°C is associated with a greater risk of urosepsis: even when patients are considered afebrile. Further evaluation in a larger cohort, possibly through a multi-centered approach, is required to confirm these findings. Durham, NC© 2010 by American Urological Association Education and Research, Inc.FiguresReferencesRelatedDetails Volume 183Issue 4SApril 2010Page: e240 Advertisement Copyright & Permissions© 2010 by American Urological Association Education and Research, Inc.MetricsAuthor Information John Mancini More articles by this author Eliza Raymundo More articles by this author Daniel Yong More articles by this author Charles Scales More articles by this author Michael Lipkin More articles by this author Michael Ferrandino More articles by this author Dorit Zilberman More articles by this author Charles Gerardo More articles by this author Glenn Preminger More articles by this author Expand All Advertisement Advertisement PDF downloadLoading ...

Predicting urine culture results by dipstick testing and phase contrast microscopy

Urine is the most frequently received clinical specimen for bacterial culture. To determine whether dipstick or microscopy results reliably predicted the presence or absence of a reportable urinary pathogen we performed dipstick testing and phase contrast microscopy on unspun urine from 500 specimens. We also investigated the relationship between the presence of squamous epithelial cells (SECs) and mixed growth on culture. For each specimen, the presence of leukocyte esterase and urinary nitrite was recorded as well as the quantity of leukocytes (WBC), SECs, and erythrocytes. All cultures had the number and type of each organism recorded. Pyuria was defined as > or =10 WBC/mm(3). Specimens with <10 SEC/mm(3) had fewer isolates (0.9 isolate per culture) than specimens with > or =10 SEC/mm(3) (two isolates per culture); therefore, SEC contamination was defined as > or =10 SEC/mm(3). Of 500 specimens, 266 (53%) had no growth and 136 (27%) had mixed growth. A total of 288 (58%) specimens had negative dipstick results and completely normal microscopy. Of these, 11 (4%) had a pure growth of a urinary pathogen but the pathogen was present in only three (1%) at > or =10(5) CFU/mL. Of 413 urine specimens without SEC contamination, 323 (78%) had either no detectable growth or pure growth compared with only 41 of 87 (47%) with SEC contamination (P<0.001). Of the 413 urine specimens without SEC contamination, 90 (22%) had > or =2 organisms compared with 46 of 87 (53%) with contamination (P<0.01). Pyuria was present in only 21 of 266 (8%) urine specimens without growth but was present in 60 of 95 (64%) specimens containing a reportable pathogen (P<0.01). SEC contamination does not reliably predict cultures with mixed growth, urine specimens with negative dipstick results and microscopy rarely contain a reportable urinary pathogen, and screening algorithms are warranted and justified.

The Use of Dipsticks to Detect Chlamydia in Males

To the Editor.— Shafer et al1reported the usefulness of urine dipsticks for testing urine samples from males for microscopic pus, the presence of which correlates well with the presence of bothChlamydia trachomatis and Neisseria gonorrhoeae. These results are similar to our own published in 19882but not mentioned by Shafer et al. We found that the 95% confidence interval for the sensitivity of the presence of leukocyte esterase was 78% to 100%; for the specificity it was 73% to 91%; and for the positive predictive value it was 34% to 72%. The results from Shafer et al for a comparable population—68%, 91%, and 49%, respectively—are remarkably close to our estimates. Ninety-five percent confidence intervals seem to be empirically relevant and should be taken seriously in interpretation of results.

A control system for monitoring the performance of leukocyte strip tests.

The control system described here is used to monitor the performance of urinary reagent-strip tests for leukocytes. The presence of leukocyte esterase in the urine is used as a marker for leukocytes in urine. The control system is based on sonicated leukocytes, isolated from whole blood. The esterase activity of this sonicate is determined by spectrophotometry with the N-tosyl-L-alanine ester of 5-phenyl-3-hydroxypyrrole as substrate. The assay result is used to determine the amount of sonicate needed to prepare buffered esterase-containing solutions. Such control solutions mimic leukocytic urines and are stable for 6 h at room temperature. The variability of the control system was tested by preparing it five times in a day on five separate days. The overall CV for Leukostix Reagent Strips (Ames Division, Miles Laboratories, Inc.) when tested with these solutions and analyzed with a reflectance spectrophotometer was 8%; for visual readings it was 10%. The overall CV for Chemstrip LN Reagent Strips (Biodynamics, Indianapolis, IN) was 10%.