Leukocyte Esterase Reagent Strips Research Articles

Determining the accuracy of the leukocyte esterase reagent strip test in the rapid diagnosis of adult septic arthritis

BackgroundsSeptic arthritis is a dangerous disease that occurs when microorganisms enter synovial fluid. It needs fast and accurate management; otherwise, it can harm the patient’s life. Currently, the tests measure WBC and PMN in SF, so we hypothesized to use a proxy that is easier and faster to measure. Leukocyte esterase is an enzyme secreted by neutrophils that can be found in the synovial fluid of SA patients. In this study, we tried to investigate the sensitivity and specificity of leukocyte esterase in diagnosing septic arthritis.MethodsWe obtained synovial fluid samples from forty-six patients suspected of having septic arthritis and fifty-eight healthy individuals and measured the WBCs, ESR, CRP, PMN, glucose, and protein of SF in 2021. We also used the leukocyte esterase dipstick test to investigate the level of LE in synovial fluid for one minute.ResultsBased on clinical and paraclinical criteria, sixteen out of the forty-six patients were diagnosed with SA. When (++) was considered positive, the sensitivity and specificity of the LE dipstick test for the diagnosis of SA were 93.7% (95% CI: 81.8–100%) and 60% (95% CI: 42.4–77.5%, P = 0.000), respectively. When both (+) and (++) were considered positive, they were 100% and 43.3% (95% CI: 25.6–61.0% P = 0.000), respectively. All the patients in the control group had negative cultures and LE test readings (specificity = 100%).ConclusionThe LE dipstick test can be a valuable diagnostic tool in the initial diagnosis of SA since it is affordable, fast, and reliable.

Diagnostic evaluation of leukocyte esterase reagent strip in bedside rapid diagnosis of spontaneous bacterial peritonitis in cirrhotic patients

Background: Spontaneous bacterial peritonitis (SBP) is the most common and serious infection of liver cirrhosis patients with ascites. If not intervened with early antibiotic treatment leads to high morbidity and mortality. Thus, early diagnosis and treatment of SBP are needed for survival. Leukocyte esterase reagent can aid in early diagnosis. Aims and Objectives: This study aimed to assess the diagnostic accuracy of the leukocyte esterase dipstick test for the diagnosis of SBP in resource poor settings. Materials and Methods: This cross-sectional study was conducted during August 2018–January 2019 on patients with cirrhotic liver disease and ascites in a tertiary care medical college hospital, Puducherry. All patients underwent abdominal paracentesis, and ascitic fluid was subjected to cell counts, biochemistry tests, culture, and leukocyte esterase test (Multistrix SG8- Seimens) at 120 s and graded with five levels. Grade 3 was positive (125 polymorphonuclear leukocytes [PMNL]/mL) and grade 4 (<500/mL), which exceeds the threshold for SBP (<250 PMNL/mL). Sensitivity, specificity, positive, and negative predictive value (PPV and NPV) was calculated. Results: A total of 50 ascitic fluids were analyzed. Nine out of 50 (18%), 16 (32%), and 4 (8%) were positive for cell count method, Leucocyte esterase reagent (LER) test and culture, respectively. The sensitivity, specificity, PPV, NPV, and diagnostic accuracy for LER test were 6.25%, 91.18%, 25%, 67.39%, and 64%, respectively. Conclusion: The LER strip test is useful for SBP diagnosis in an emergency and resource poor setting. It provides good diagnostic accuracy and high NPV and it is cost effective and better bedside tool for SBP diagnosis.

Accuracy of leukocyte esterase reagent strip test and platelet indices for early diagnosis of ascitic fluid infection in liver cirrhosis

Background: Spontaneous bacterial peritonitis (SBP) is one of the serious complexities in patients with cirrhosis and ascites. 30-50% of death may occur if it not treated properly. The leucocyte esterase reagent (LER) strip test is a special apparatus for prior detection of neutrophils in the ascetic fluid. The aim of the study was to investigate the diagnostic accuracy of the LER strip test and platelet indices in the early detection of SBP in cirrhotic patients. Methods: This cross-sectional study was carried out in the department of gastrointestinal hepatobiliary and pancreatic disorders (GHPD), BIRDEM, Dhaka, Bangladesh, from January 2018 to October 2019. A total of 110 indoor patients of liver cirrhosis with ascites were enrolled after fulfilment of the inclusion and exclusion criteria with adequate history taking and clinical examination. Results: Out of 110 cases, 68 were male and 42 were female, and among them 23 (20.9%) patients had SBP. LER strip test at grade 4 set as a cut-off value which showed sensitivity, specificity, positive predictive value (PPV), negative predictive value (NPV), accuracy was 91.3%, 90.8%, 70%, 97.5%, and 90% respectively. Mean platelet volume (MPV) and platelet distribution width (PDW) were done by complete blood count, where the MPV cut-off value set as 12.5 fl showed sensitivity, specificity, PPV, NPV, and accuracy were 82.6%, 90.8%, 66%, 96.25%, and 88.18% respectively. PDW cut-off value set on 18.10% revealed sensitivity, specificity, PPV, NPV, accuracy was 82.6%, 83.9%, 50%, 95.71% and 79% respectively. ROC curve was plotted to set the cut-off value by examining sensitivity and specificity. Results were considered statistically significant at p<0.05. Conclusions: This study was undertaken to detect LER strip tests that showed significant results in bedside diagnosis of SBP. Apart from this, a significant increase in MPV and PDW was observed in SBP. So, LER strip tests and platelet indices measurement can be economical and reliable appliances for early diagnosis of SBP.

Evaluation of leukocyte esterase reagent strip test for rapid bedside diagnosis of spontaneous bacterial peritonitis

Spontaneous bacterial peritonitis (SBP) is a common complication of cirrhosis with high morbidity and mortality. Early diagnosis and treatment improve survival. Diagnosis is made by ascitic fluid Polymorphoneuclear leukocytes (PMNL) count of >250/mm3 which takes hours and may not be available in rural settings. Leukocyte esterase reagent strips (LERS) test have shown high sensitivity, specificity, and negative predictive value in the diagnosis of SBP. This study was conducted to find the utility of the LERS test for the diagnosis of SBP. This was a prospective hospital-based study conducted at the National Academy of Medical Sciences, Bir Hospital, Nepal. LERS test was performed on ascitic fluid from 140 cirrhotic patients. Colorimetric grading was compared with PMNL count for diagnosing SBP. Sensitivity, specificity, positive predictive value (PPV), negative predictive value (NPV), and accuracy for diagnosing SBP calculated for grade 3 and grade 4 as cut-offs. Among 140 patients, SBP was diagnosed in 27. Grade 3 as cut-off, sensitivity, specificity, PPV, and NPV for the LERS test were 96.3, 90.2, 70.3, and 99 percent respectively. For grade 4 as cut-off, sensitivity, specificity, PPV, and NPV were 81.5, 99.1, 95.6, and 95.7 percent respectively. Accuracy were 91.4 and 95.2 percent for grade 3 and 4 as cut-off respectively. LERS test has shown high sensitivity, specificity, and negative predictive value for the diagnosis of SBP in cirrhotic ascitis. Being simple, rapid, and cost-effective, it can be useful at bedside to start early antibiotic therapy before availability of the PMNL count report.

Diagnosis of spontaneous bacterial peritonitis in patients with chronic liver disease: Role of leukocyte esterase dipstick test.

Objective: To find out the efficiency of leukocyte esterase reagent strip (LERS) testing for the diagnosis of spontaneous bacterial peritonitis (SBP). Study Design: Cross Sectional, Validation study. Setting: Department of Medicine, Unit-III, Bahawal Victoria Hospital, Bahawalpur. Period: January-December 2019. Material & Methods: A total of 235 patients of both gender, aged 18-60 years, having CLD with ascites, with any child pugh class and duration of CLD between 6-12 months were enrolled. Ascitic fluid was obtained at bedside and immediately dispatched for testing in a clean and dry test tube with reagent strip Multistix® 10 SG. Screening tests were calculated for accuracy of LERS test with respect to confirmed cytology testing. Results: Majority, 152 (64.7%) were male, 94 (40.0%) between 51-60 years age group and 146 (62.1%) had child pugh class C. Overall, mean age was noted to be 46.82+9.45 years. LERS testing turned out to be positive among 138 (5837%) cases. Confirmation of SBP through cytology was noted among 141 (60.0%). Sensitivity (SE), specificity (SP), positive predictive value (PPV), negative predictive value (NPV) and diagnostic accuracy of LERS for the diagnosis of SBP with respect to cytology confirmation was calculated to be 90.8%, 89.4%, 92.8%, 86.6% and 90.2% respectively. Conclusion: The LERS testing was found to have high SE, SP, PPV, NPV and diagnostic accuracy in diagnosing SBP among patients of CLD with ascites. LERS can be used at bedside while it very simple and easy to perform.

Role of Dipstick (Leucocyte Esterase Reagent Strips) in the Rapid Bedside Diagnosis of Spontaneous Bacterial Peritonitis

Objectives: To evaluate the dipstick in the rapid bedside diagnosis of spontaneous bacterial peritonitis (SBP) and avoid delay in initiation of antibiotic therapy and evaluate the prevalence of SBP by a conventional method. Methods: A prospective analysis was done on inpatients and OPD patients with cirrhotic ascites at Jaipur Golden Hospital Delhi, India. The study included 110 consecutive patients with cirrhotic ascites. The patients were divided into 2 groups those with the polymorph nuclear leucocytes (PMNs) >250/mm3 on cell count (positive result) and those with PMNs <250/mm3 (Negative results) and were then compared to the dipstick results. The results were used to find the sensitivity, specificity, positive predictive value, negative predictive value, and accuracy of the rapid dipstick method for the diagnosis of SBP. In addition, the data was used to calculate the prevalence of SBP in our hospital. Results: A total number of 110 patients with cirrhotic ascites were studied who were presented to the Jaipur Golden Hospital, New Delhi, India with the complaint of abdominal distension. A total of 20 patients were diagnosed with SBP by the manual cell count method which is considered a gold standard for the diagnosis of SBP, and 90 patients were diagnosed as non-SBP. We re-diagnosed these 20 patients with SBP with a dipstick method, the dipstick method showed a positive result for 18 patients (90%) and a negative result for 2 patients (10%). Conclusion: In the SBP group, the dipstick showed 18 true positives and 2 false negatives. In the non-SBP group of 90 patients, the dipstick method showed negative results in all the patients with no positive results. Thus, the dipstick showed 100% true negatives with 0% false positives. The prevalence of SBP in patients with cirrhotic ascites in a hospital was found at 18.2%.

Leukocyte esterase reagent strips: rapid, economical and reliable cow side test for subclinical endometritis

Leukocyte esterase reagent strips: rapid, economical and reliable cow side test for subclinical endometritis

Performance of Leukocyte Esterase Reagent Strips in the Detection of Spontaneous Bacterial Peritonitis in Cirrhotic Patients: A Systematic Review and Meta-analysis

Spontaneous bacterial peritonitis (SBP) is a bacterial infection associated with a high mortality rate in cirrhotic patients. The gold standard for the detection of SBP is a manual cell count from ascitic fluid; however, alternative screening methods are under investigation. In particular, leukocyte esterase reagent strips (LERS) has been studied as an alternative method to detect SBP with a low cost and instant turnaround time. Therefore, this study aims to evaluate the performance of LERS in the detection of SBP. A literature search was performed for studies evaluating LERS for the detection of SBP on PubMed, Embase, Scopus, Cochrane, and clinical trial registries. Summary sensitivity, specificity, log diagnostic odds ratio (LDOR), and the area under the summary receiver operating curve (AUC) were calculated according to the respective manufacturer. In total, 31 studies were evaluated. The summary sensitivity of Aution Sticks, Combur, Multistix, Periscreen reagent strips was 0.962 (95% confidence interval [CI] 0.926, 0.998), 0.892 (95% CI 0.846, 0.938), 0.806 (95% CI 0.738, 0.874), and 0.939 (95% CI 0.900, 0.979), respectively. The summary specificity of Aution Sticks, Combur, Multistix, and Periscreen reagent strips was 0.940 (95% CI 0.904, 0.976), 0.922 (95% CI 0.874, 0.970), 0.974 (95% CI 0.962, 0.985), and 0.672 (95% CI 0.381, 0.963), respectively. LERS appears to have a notable overall performance for the detection of SBP. LERS appeared to be an acceptable alternative to diagnose SBP in facilities without ability to perform cell count. However, there were significant differences in performance between each manufacturer.

Synovial fluid analysis with leukocyte esterase reagent strip test.

To determine whether leukocyte esterase reagent strip test (LERST) analysis could help distinguish inflammatory arthritis from mechanical joint effusion. We analyzed synovial fluid (SF) from consecutive patients with a non-traumatic joint effusion during a 6-month period. Inflammatory SF was defined by white blood cell (WBC) count ≥ 2000/mm3. The LERST was performed with both semi-quantitative visual analysis (VA) and automated colorimetric reader (ACR) analysis. Leukocytes ≥ 1+ was considered a positive LERST result and WBC count was the reference. We obtained 100 SF samples (87 knees, 7 ankles, 5 hips, and 1 elbow) from 100 patients (mean ± SD age 61 ± 17 years, 59% men). The laboratory analyzed 88 SF samples (37 mechanical and 51 inflammatory). The remaining 12 SF samples were 10 hemarthrosis not allowing LERST analysis and 2 samples with coagulum not allowing WBC count. As compared with the laboratory analysis, the LERST had sensitivity and specificity 55% and 89% with VA and 47% and 92% with ACR analysis. The positive and negative predictive values were 87.5% and 59% with VA and 89% and 55% with ACR analysis. We found almost perfect agreement between VA and ACR results (kappa 0.70 [95% CI 0.50-0.90]). The WBC count increased with number of + observed after VA. Our results confirm that the LERST is able to detect inflammation in SF of native joints, thereby representing a useful and cheap tool in primary care. Its low sensitivity limits its use for ruling out inflammatory disorders. Key Points • Reagent strip tests can detect inflammation in synovial fluid. • In primary care practice, this method is cheap and easy to do.

The periscreen strip is an accurate and rapid method to diagnose spontaneous bacterial peritonitis among patients with acute-on-chronic liver failure

Leukocyte esterase reagent strips may help diagnose spontaneous bacterial peritonitis (SBP), but their effective application among patients with acute-on-chronic liver failure (ACLF) remains unknown. This study aimed to assess the performance of periscreen strips in the rapid diagnosis of SBP among patients with ACLF. Periscreen strips were used to test 261 ascites samples taken from 251 inpatients with ACLF between January 2014 and June 2019. The colors of the reagent strip were divided into four colorimetric graduations ('negative', 'trace', 'small', and 'large'), among which 'trace' is used as the SBP detection threshold. The polymorphonuclear neutrophils (PMN) of ascites ≥250/mm3 was used as the gold standard for SBP diagnosis. SBP was detected in 92 (35.2%) ascite samples. The ascites PMN count of 'negative' (32.5/mm3) was lower than those of 'trace' (248.2/mm3), 'small' (379.0/mm3), and 'large' (7426.0/mm3) (P < 0.001). The colorimetric graduations of the strips were positively correlated with ascites PMN count (r = 0.867, P < 0.001). Periscreen strips had 100% sensitivity, 91.1% specificity, 86.0% positive predictive value, 100% negative predictive value, 11.3 positive likelihood ratios, and 0 negative likelihood ratios. For patients with negative results judged by the gold standard, ascites white blood cells count [odds ratio (OR) = 1.007) and ascites PMN count (OR = 1.028) were independent predictors of false-positive cases. Liver failure did not affect the diagnostic performance of periscreen strips. Therefore, these strips can efficiently and rapidly diagnose SBP among patients with ACLF.

Accuracy of Leukocyte Esterase Reagent Strip (LERS) test for rapid bedside screening of spontaneous bacterial peritonitis: An observational study.

Introduction:Spontaneous bacterial peritonitis (SBP) is a frequent and severe complication in cirrhotic patients with ascites. SBP is generally diagnosed based on an increased number of polymorphonuclear neutrophils in the ascitic fluid (>250/mm3) and positive culture. Usually fluid analysis and culture take time and precious hours are lost in starting therapy. Leukocyte Esterase Reagent Strips (LERS) have consistently given a high negative predictive value (>95% in the majority of the studies).Aims and Objectives:Aim was to evaluate the diagnostic utility of leukocyte esterase reagent strip for rapid diagnosis of SBP in patients who underwent abdominal paracentesis and to calculate the sensitivity, specificity, positive, and negative predictive values.Methodology:The study was carried out on 64 patients with ascites. Cell count of AF as determined by colorimetric scale of Multistix 10 SG reagent strip was compared with counting chamber method (PMNL count ≥250 cells/mm3 was considered positive).Results:Of the 64 patients SBP was diagnosed in 17 patients, 47 patients were negative for SBP by manual cell count. At cut off of 2+; sensitivity to diagnose SBP was 100%; specificity of 94%; PPV being 57% and NPV of 94%. at the cut off level of 3+; sensitivity decreased down to 76%; specificity increased to 100%; PPV of 100% and NPV of 93.75%. Overall accuracy at 2 + and 3 + was respectively 94.5% and 93.75%.Conclusion:In this study we have found good sensitivity and specificity for the prompt detection of elevated polymorphonuclear neutrophil count. A negative test result excludes SBP with a high degree of certainty. Thus, it represents a convenient, inexpensive, simple bedside screening tool for SBP diagnosis.

STUDY OF MEAN PLATELET VOLUME VERSUS LEUCOCYTE ESTERASE AS A MARKER IN DIAGNOSIS OF SPONTANEOUS BACTERIAL PERITONITIS

Background: Spontaneous bacterial peritonitis (SBP) is a severe and frequent complication of cirrhosis with a high mortality rate. Early diagnosis and treatment of SBP is necessary for survival. Objective: To study the mean platelet volume (MPV) versus leucocyte esterase as a marker in diagnosis of decompensated cirrhotic patients with spontaneous bacterial peritonitis. Patients and methods: A total of 200 patients with decompensated liver cirrhosis and ascites, were admitted to the Department of Gastroenterology and Hepatology in Nasser Institute, and were enrolled in this study between January 2016 and October 2017. Patients were divided into two equal groups; group (I) was diagnosed non SBP and group (II) was diagnosed SBP. All patients underwent abdominal paracentesis, and the ascitic fluid was processed for cell count, leukocyte esterase reagent strip test (LERS) (URIT 10V) and culture. All patients underwent assessment of MPV in CBC. Results: Diagnostic performance of mean platelet volume showed that we can use MPV as a good diagnostic marker for SBP with sensitivity 75 %, specificity 99% and accuracy 93.2 %. The best cut off value for discriminating patients with SBP from patients without SBP was 9.2 fl. The test of ascetic fluid by leukocyte esterase reagent strips showed that specificity = 93% , sensitivity = 80%, positive predictive value (PPV) = 92%, negative predictive value (NPV) =82.3% and accuracy = 86.5%. Conclusion: MPV and LERS can be used as a good marker in diagnosis of SBP in cirrhotic patients with ascites.

STUDY OF MEAN PLATELET VOLUME VERSUS LEUCOCYTE ESTERASE AS A MARKER IN DIAGNOSIS OF SPONTANEOUS BACTERIAL PERITONITIS

Background: Spontaneous bacterial peritonitis (SBP) is a severe and frequent complication of cirrhosis with a high mortality rate. Early diagnosis and treatment of SBP is necessary for survival. Objective: To study the mean platelet volume (MPV) versus leucocyte esterase as a marker in diagnosis of decompensated cirrhotic patients with spontaneous bacterial peritonitis. Patients and methods: A total of 200 patients with decompensated liver cirrhosis and ascites, were admitted to the Department of Gastroenterology and Hepatology in Nasser Institute, and were enrolled in this study between January 2016 and October 2017. Patients were divided into two equal groups; group (I) was diagnosed non SBP and group (II) was diagnosed SBP. All patients underwent abdominal paracentesis, and the ascitic fluid was processed for cell count, leukocyte esterase reagent strip test (LERS) (URIT 10V) and culture. All patients underwent assessment of MPV in CBC. Results: Diagnostic performance of mean platelet volume showed that we can use MPV as a good diagnostic marker for SBP with sensitivity 75 %, specificity 99% and accuracy 93.2 %. The best cut off value for discriminating patients with SBP from patients without SBP was 9.2 fl. The test of ascetic fluid by leukocyte esterase reagent strips showed that specificity = 93% , sensitivity = 80%, positive predictive value (PPV) = 92%, negative predictive value (NPV) =82.3% and accuracy = 86.5%. Conclusion: MPV and LERS can be used as a good marker in diagnosis of SBP in cirrhotic patients with ascites.

Diagnostic Accuracy of Serum, Synovial, and Tissue Testing for Chronic Periprosthetic Joint Infection After Hip and Knee Replacements: A Systematic Review.

Chronic periprosthetic joint infection (PJI) is a devastating complication that can occur following total joint replacement. Patients with chronic PJI report a substantially lower quality of life and face a higher risk of short-term mortality. Establishing a diagnosis of chronic PJI is challenging because of conflicting guidelines, numerous tests, and limited evidence. Delays in diagnosing PJI are associated with poorer outcomes and morbid revision surgery. The purpose of this systematic review was to compare the diagnostic accuracy of serum, synovial, and tissue-based tests for chronic PJI. This review adheres to the Cochrane Collaboration's diagnostic test accuracy methods for evidence searching and syntheses. A detailed search of MEDLINE, Embase, the Cochrane Library, and the grey literature was performed to identify studies involving the diagnosis of chronic PJI in patients with hip or knee replacement. Eligible studies were assessed for quality and bias using the Quality Assessment of Diagnostic Accuracy Studies-2 (QUADAS-2) tool. Meta-analyses were performed on tests with sufficient data points. Summary estimates and hierarchical summary receiver operating characteristic (HSROC) curves were obtained using a bivariate model. A total of 12,616 citations were identified, and 203 studies met the inclusion criteria. Of these 203 studies, 170 had a high risk of bias. Eighty-three unique PJI diagnostic tests were identified, and 17 underwent meta-analyses. Laboratory-based synovial alpha-defensin tests and leukocyte esterase reagent (LER) strips (2+) had the best performance, followed by white blood-cell (WBC) count, measurement of synovial C-reactive protein (CRP) level, measurement of the polymorphonuclear neutrophil percentage (PMN%), and the alpha-defensin lateral flow test kit (Youden index ranging from 0.78 to 0.94). Tissue-based tests and 3 serum tests (measurement of interleukin-6 [IL-6] level, CRP level, and erythrocyte sedimentation rate [ESR]) had a Youden index between 0.61 to 0.75 but exhibited poorer performance compared with the synovial tests mentioned above. The quality of the literature pertaining to chronic PJI diagnostic tests is heterogeneous, and the studies are at a high risk for bias. We believe that greater transparency and more complete reporting in studies of diagnostic test results should be mandated by peer-reviewed journals. The available literature suggests that several synovial fluid-based tests perform well for diagnosing chronic PJI and their use is recommended in the work-up of any suspected case of chronic PJI. Diagnostic Level III. See Instructions for Authors for a complete description of levels of evidence.

Sensitivity of a bedside reagent strip for the detection of spontaneous bacterial peritonitis in ED patients with ascites

Study objectiveTo determine the sensitivity of a highly sensitive bedside leukocyte esterase reagent strip (RS) for detection of spontaneous bacterial peritonitis (SBP) in emergency department (ED) ascites patients undergoing paracentesis. MethodsWe conducted a prospective, observational cohort study of ED ascites patients undergoing paracentesis at two academic facilities. Two practitioners, blinded to each other's results, did a bedside RS analysis of the peritoneal fluid in each patient and documented the RS reading at 3-min according to manufacturer-specified colorimetric strip reading as either “negative”, “trace”, “small”, or “large”. The primary outcome measure was sensitivity of the RS strip for SBP (absolute neutrophil count ≥ 250 cells/mm3) at the “trace” threshold (positive equals trace or greater). ResultsThere were 330 cases enrolled, with 635 fluid analyses performed. Of these, 40 fluid samples had SBP (6%). Bedside RS had a sensitivity, specificity, positive predictive value, and negative predictive value of 95% (95% CI 82%–99%), 48% (95% CI 44%–52%), 11% (95% CI 10%–11%), and 99% (95% CI 97%–99%) respectively at the “trace” threshold for the detection of SBP. ConclusionBedside use of the RS in ED ascites patients demonstrated high sensitivity for SBP. Given the wide confidence intervals, we cannot currently recommend it as a stand-alone test. We recommend further study with a larger number of SBP patients, potentially combining a negative RS result with low clinical suspicion to effectively rule out SBP without formal laboratory analysis.

Validity of leukocyte esterase reagent (LER) strip in diagnosing infectious pleural effusion

Background: Pleural fluid sampling and analysis are essential to confirm an infection. In a resource-limited health care setting or if biochemistries of the aspirated fluid are not available on an emergency basis, urine reagent strips applied to pleural fluid may expedite diagnostic information. Present study was aimed to evaluate the effectiveness of leukocyte esterase reagent (LER) strip in diagnosing infectious pleural effusion and to correlate the reaction of LER strip with various stages of infectious effusions.Methods: A prospective longitudinal study was conducted in the medical ward of Government Mohan Kumaramangalam Medical College Hospital for a period of one year. Pleural effusion patients with associated immuno-compromised conditions like diabetes mellitus, patients on steroids, HIV reactive patients, chronic obstructive lung disease were included for the study. A totalof 84 patients were included for the study. Exploratory thoracocentesis was done with an 8 mm needle and pleural fluid was obtained and sent for cell count and biochemical testing. The pleural fluid was also tested using the leukocyte esterase reagent strip. The results were recorded as 0, 1+, 2+, 3+ based on the density of violet colour.Results: The leukocyte esterase reagent strip test showed totally negative results in all patients with transudative pleural effusion and also in patients with tuberculous pleural effusion, whereas among patients with infectious pleural effusion other than tuberculosis LER strip test showed negative to only 15% of the patients and for remaining it ranged from 1+ to 3+. The validity of leukocyte esterase strip test was tested in comparison with the gold standard culture test. The accuracy of LER strip test was found to be 88.6%, and the sensitivity and specificity was 90.2% and 66.2% respectively.Conclusions: Reagent strips may speed up the bedside diagnosis of infectious effusions. However, where access to standard biochemical pleural fluid analysis is not available this dipstick tests would add value to the management of the patients.

Diagnosis of spontaneous bacterial peritonitis in children using leukocyte esterase reagent strips and granulocyte elastase immunoassay.

Aim of the studyWe aimed to assess the utility and rapidity of granulocyte elastase (GE) latex immunoassay and leukocyte esterase (LE) reagent strips for the diagnosis of spontaneous bacterial peritonitis (SBP) in hepatic children with ascites.Material and methodsThis study included 80 ascitic fluid (AF) samples from 45 patients with chronic liver diseases. They were divided into 2 groups (SBP and non-SBP groups). White blood cells > 500 cell/mm3 or polymorphonuclear leukocytes > 250 cell/mm3 were considered as a positive result for the diagnosis of SBP. The AF obtained at bedside was immediately tested with an LE enzyme reagent strip, and another sample was aliquoted for measurement of serum GE.ResultsOn doing LE dipstick strips, all the non-SBP group gave no coloration with LE strips while 62% of the SBP group gave coloration. LE strips had accuracy of 86.25% in differentiating SBP and non-SBP at a cut-off value of 1 (color grade 1). The diagnostic performance of GE in differentiating SBP and non-SBP was assessed and showed accuracy of 70% for a cutoff value of 123.5 ng/ml.ConclusionsApplication of LE reagent strips is a bedside, rapid, easy-to-use, and inexpensive method for diagnosis of SBP. It has an accuracy of 86.25% in differentiating SBP and non-SBP, which is higher than more complicated and delayed methods such as GE latex immunoassay, which has an accuracy of 70%.

Determining False Positive Rates of Leukocyte Esterase Reagent Strip When Used as a Detection Tool for Joint Infection

BackgroundUse of leukocyte esterase (LE) testing of synovial fluid as an adjunct to the infection workup in total joint arthroplasty patients has been advocated. The purpose of this study was to determine the false positive rate of this test. MethodsTwo hundred patients with the diagnosis of degenerative osteoarthritis undergoing a total knee arthroplasty were identified for this study. The knee joint was aspirated under sterile conditions before performing the total knee arthroplasty. The fluid was analyzed with an LE reagent strip. ResultsThere were 27 bloody and 17 dry aspirations. One hundred forty-nine patients produced an aspiration that allowed for LE testing. There was 1 positive LE result. The specificity of the LE test was found to be 99.3%. ConclusionThese data suggest the LE strip as a part of the workup for infection in a native knee should yield few false positive results.

Diagnostic Laboratory Markers for Spontaneous Bacterial Peritonitis

Spontaneous bacterial peritonitis (SBP) is an often-lifethreatening bacterial infection in patients with liver cirrhosis with ascites. Useful laboratory methods for early diagnosis are essential. The gold standard method for the diagnosis of SBP is a polymorphonuclear leukocyte (PMN) count of ≥250 cells/mm3 in the ascitic fluid. Some studies have investigated the usefulness of other novel laboratory methods for the diagnosis of SBP. This paper reviews studies of diagnostic markers for SBP, such as procalcitonin, calprotectin, and leukocyte esterase reagent strips in ascitic fluid. At present, serum procalcitonin is a relatively sensitive and specific marker for the diagnosis of SBP. The usefulness of ascitic levels of procalcitonin and calprotectin for differentiating between SBP and sterile ascites is still uncertain because of the small number of studies. Although the sensitivity of leukocyte esterase reagent strips for diagnosing SBP is variable, a negative test result may predict absence of SBP.

EVALUATION OF LEUKOCYTE ESTERASE REAGENT STRIPS TEST IN THE DIAGNOSIS OF SPONTANEOUS BACTERIAL PERITONITIS IN CHILDREN WITH CIRRHOSIS.

Spontaneous bacterial peritonitis is defined as an ascetic fluid infection without an evident intra-abdominal surgically treatable source. Spontaneous bacterial peritonitis is one of the severe complications in patients with cirrhosis and ascites. Without early antibiotic treatment, this complication is associated with high mortality rate; therefore, early diagnosis and treatment of spontaneous bacterial peritonitis is necessary for survival. Leukocyte esterase reagent can rapidly diagnose the spontaneous bacterial peritonitis. This study aimed to find out the diagnostic accuracy of leukocyte esterase dipstick test for the diagnosis of spontaneous bacterial peritonitis. A single centered hospital-based cross-sectional study was conducted during July 2013 to August 2014 on children with cirrhotic liver disease and ascites who were admitted in the Department of Pediatric Gastroenterology in Nemazee Hospital affiliated to Shiraz University of Medical Sciences (Iran). All patients underwent abdominal paracentesis, and the ascitic fluid was processed for cell count, leukocyte esterase reagent strip test (Combiscreen SL10) and culture. Spontaneous bacterial peritonitis was defined as having a polymorphonuclear count (PMN ≥250/m3) in ascitic fluid. Sensitivity, specificity, positive predictive value and negative predictive value of leukocyte esterase test were calculated according to the formula. Totally, 150 ascitic fluid sample of cirrhotic male patients (53.2%) and their mean age (4.33±1.88 years) were analyzed. Biliary atresia (n=44, 29.4%) and idiopathic neonatal hepatitis (n=29, 19.3%) were the most frequent etiology of cirrhosis. Also, abdominal pain (68.6%) and distension (64%) were the most common presenting complaint. Of all cases, 41 patients (27.35%) were diagnosed to have spontaneous bacterial peritonitis (PMN ≥250/mm3). Sensitivity and specificity of leukocyte esterase reagent test according to PMNs ≥250 mm3 were 87.80% and 91.74%, also on ascitic fluid culture results were 88.23% and 77.44%. Positive predictive value and negative predictive value of this test in PMNs ≥250 mm3 were 80% and 95.23% and in cases with positive culture 33.33% and 98.09% were obtained, respectively. Efficiency of leukocyte esterase reagent test in diagnosing spontaneous bacterial peritonitis, according to PMNs ≥250 mm3 and culture results were 90.66% and 78.66%. The leukocyte esterase strip test may be used as rapid test for diagnosis of spontaneous bacterial peritonitis due to its high diagnostic validity.