Dipstick Urinalysis Research Articles

The Diagnosis of Urinary Tract infection in Young children (DUTY): a diagnostic prospective observational study to derive and validate a clinical algorithm for the diagnosis of urinary tract infection in children presenting to primary care with an acute illness.

It is not clear which young children presenting acutely unwell to primary care should be investigated for urinary tract infection (UTI) and whether or not dipstick testing should be used to inform antibiotic treatment. To develop algorithms to accurately identify pre-school children in whom urine should be obtained; assess whether or not dipstick urinalysis provides additional diagnostic information; and model algorithm cost-effectiveness. Multicentre, prospective diagnostic cohort study. Children < 5 years old presenting to primary care with an acute illness and/or new urinary symptoms. One hundred and seven clinical characteristics (index tests) were recorded from the child's past medical history, symptoms, physical examination signs and urine dipstick test. Prior to dipstick results clinician opinion of UTI likelihood ('clinical diagnosis') and urine sampling and treatment intentions ('clinical judgement') were recorded. All index tests were measured blind to the reference standard, defined as a pure or predominant uropathogen cultured at ≥ 10(5) colony-forming units (CFU)/ml in a single research laboratory. Urine was collected by clean catch (preferred) or nappy pad. Index tests were sequentially evaluated in two groups, stratified by urine collection method: parent-reported symptoms with clinician-reported signs, and urine dipstick results. Diagnostic accuracy was quantified using area under receiver operating characteristic curve (AUROC) with 95% confidence interval (CI) and bootstrap-validated AUROC, and compared with the 'clinician diagnosis' AUROC. Decision-analytic models were used to identify optimal urine sampling strategy compared with 'clinical judgement'. A total of 7163 children were recruited, of whom 50% were female and 49% were < 2 years old. Culture results were available for 5017 (70%); 2740 children provided clean-catch samples, 94% of whom were ≥ 2 years old, with 2.2% meeting the UTI definition. Among these, 'clinical diagnosis' correctly identified 46.6% of positive cultures, with 94.7% specificity and an AUROC of 0.77 (95% CI 0.71 to 0.83). Four symptoms, three signs and three dipstick results were independently associated with UTI with an AUROC (95% CI; bootstrap-validated AUROC) of 0.89 (0.85 to 0.95; validated 0.88) for symptoms and signs, increasing to 0.93 (0.90 to 0.97; validated 0.90) with dipstick results. Nappy pad samples were provided from the other 2277 children, of whom 82% were < 2 years old and 1.3% met the UTI definition. 'Clinical diagnosis' correctly identified 13.3% positive cultures, with 98.5% specificity and an AUROC of 0.63 (95% CI 0.53 to 0.72). Four symptoms and two dipstick results were independently associated with UTI, with an AUROC of 0.81 (0.72 to 0.90; validated 0.78) for symptoms, increasing to 0.87 (0.80 to 0.94; validated 0.82) with the dipstick findings. A high specificity threshold for the clean-catch model was more accurate and less costly than, and as effective as, clinical judgement. The additional diagnostic utility of dipstick testing was offset by its costs. The cost-effectiveness of the nappy pad model was not clear-cut. Clinicians should prioritise the use of clean-catch sampling as symptoms and signs can cost-effectively improve the identification of UTI in young children where clean catch is possible. Dipstick testing can improve targeting of antibiotic treatment, but at a higher cost than waiting for a laboratory result. Future research is needed to distinguish pathogens from contaminants, assess the impact of the clean-catch algorithm on patient outcomes, and the cost-effectiveness of presumptive versus dipstick versus laboratory-guided antibiotic treatment. The National Institute for Health Research Health Technology Assessment programme.

Incidence, care quality and outcomes of patients with acute kidney injury in admitted hospital care.

Acute kidney injury (AKI) is common in acute hospital admission and associated with worse patient outcomes. To measure incidence, care quality and outcome of AKI in admitted hospital care. Forty-six of 168 acute NHS healthcare trusts in UK caring for 2 million acute hospital admissions per annum collected information on adults identified with AKI stage 3 (3-fold rise in serum creatinine or creatinine >354 µmol/l) through routine biochemical testing over a 5-month period in 2012. Information was collected on patient and care characteristics. Primary outcomes were survival and recovery of kidney function at 1 month. A total of 15 647 patients were identified with biochemical AKI stage 3. Case note reviews were available for 7726 patients. In 80%, biochemical AKI stage 3 was confirmed clinically. Among this group, median age was 75 years, median length of stay was 12 days and the overall mortality within 1 month was 38%. Significant factors in a multivariable model predicting survival included age and some causes of AKI. Dipstick urinalysis, medication review, discussion with a nephrologist and acceptance for transfer to a renal unit were also associated with higher survival, but not early review by a senior doctor, acceptance for transfer to critical care or requirement for renal replacement therapy. Eighteen percent of people did not have their kidney function checked 1 month after the episode had resolved. This large study of in-hospital AKI supports the efficacy of biochemical detection of AKI in common usage. AKI mortality remains substantial, length of stay comparable with single-centre studies, and much of the variation is poorly explained (model Cox and Snell R2 = 0.131) from current predictors.

Childhood urinary tract infections: an evidence-based approach

Abstract Urinary tract infections (UTIs) are a common childhood problem and a frequent reason for presentation in both primary care and hospital settings. Severity ranges from simple cystitis to pyelonephritis; symptoms may be typical of urinary tract infection or may be non-specific. Decision-making can be challenging in the acute setting and when planning follow-up. Clinicians need evidence to correctly answer questions such as: What method of sampling is most reliable? Can I rely on dipstick urinalysis to diagnose a UTI? Are infants particularly at risk of meningitis during UTI and should I obtain cerebro-spinal fluid and what imaging will aid my management of this child? Even experienced clinicians vary in their answers to these clinical questions. Through a case-based approach, this article aims to help clinicians make these decisions, highlighting well-established guidance, in addition to newly published evidence.

English

Sickle cell disease (SCD), the commonest single gene disorder amongst Nigerian children, may present as sickle cell nephropathy (SCN). SCN is detectable by persistent proteinuria, a “nephrotoxin” that contributes to progression of SCN to end stage renal disease. Unfortunately, screening for persistent proteinuria is an uncommon practice among Nigerian children with SCD, even when reduction of proteinuria is a proven renoprotective therapy. Dipstick urinalysis was done to detect persistent proteinuria (proteinuria of trace and above, on first contact and a month on follow-up in the same subject) among consecutive steady state sickle cell anaemia (haemoglobin SS confirmed using cellulose acetate paper electrophoresis) children attending sickle cell clinic at the University of Ilorin Teaching Hospital between October, 2004 and July, 2005. Subjects with persistent proteinuria were also assessed for estimated glomerular filtration rate (eGFR) using the method described by Schwartz et al. A total of 75 children aged between 1 to 17 years, comprising 35 males and 40 females, were studie. Proteinuria was found in 6 (8%) subjects (5 males, 1 female) and in 5 (6.7%) subjects (3 males, 2 females) on first contact and one month on follow-up, respectively. Persistent proteinuria was only seen in 3 (4%) male subjects (older than 10 years age) whose eGFR was not impaired. Although proteinuria occurred more commonly among male subjects than females on first contact and at follow-up, this observation was not statistically significant (p = 0.175 at first contact, p = 0.224 at follow-up). Proteinuria also occurred more among subjects older than 10 years of age at both contacts, this association was also not significant (p = 0. 071 on first contact, p value = 0.10 at follow-up). Although, a low prevalence of persistent proteinuria was found among the sickle cell anaemia children studied, its screening should become a routine to identify children who will benefit from antiproteinuric treatment. Key words: Persistent proteinuria, steady state sickle cell anaemia, children, Ilorin, Nigeria.

La bandelette urinaire peut-elle être utilisée pour le diagnostic des colonisations bactériennes urinaires dans le bilan préopératoire urologique?

The use of the dipstick urinalysis has been validated for the diagnosis of symptomatic urinary infections, cystitis and pyelonephritis thanks to an excellent negative predictive value. For prostatitis, it is rather its positive predictive value that is interesting. The aim of this study is to validate its use in the screening of urinary colonizations in the preoperative assessment in urology. A monocentric prospective study was carried out for one year in 2011 comparing the data from the urine dipstick test with a fresh-voided midstream urinary examination and culture performed on the day of admission with the same urine sample in 598 asymptomatic patients programmed for a urological procedure. The gold standard to diagnose a microbiological-confirmed urinary tract infection or colonization was uropathogen growth of ≥10(3) colony-forming units per ml (cfu/mL) with or without leucocyturia. The study disclosed 5% of colonized patients. The urine dipstick test had a 65% sensitivity and a 97% negative predictive value. However, the low sensitivity of the urine dipstick test entailed 34% of false negatives. In spite of a good negative predictive value linked to a low prevalence of colonized patients (5%), the low sensitivity of the urine dipstick test entails a non-negligible number of false negatives. Its use as a single test of preoperative screening would expose colonized patients to the prospect of an operation, which seems to be unacceptable for some of them, notably endoscopic ones. 4.

Confronting the Need for Evidence Regarding Prevention.

* Abbreviations: AAP — : American Academy of Pediatrics USPSTF — : US Preventive Services Task Force When both of us entered pediatrics, we learned that screening dipstick urinalyses was a standard part of well-child care, even though data from at least the 1970s questioned its rationale based on the high false-positive rate and the identification of self-limited disease.1 Screening seemed sensible and innocuous, and neither of us questioned it at the time. Although we were both aware of the debate about benefit, we do not recall hearing about the potential harms of dipstick screening. Over time, the evidence regarding the lack of benefit grew and the recommendation for screening urinalysis was limited to the 5-year-olds2 and then eventually dropped.3 Here is the question: Should a screening test that seems effective be adopted into routine practice with the expectation that evidence would eventually affirm its use or remove it from clinical care? Do we “do first, ask later?” We all know practices in our communities that still routinely use screening urinalyses out of concern about missing a “case” regardless of the potential harm and questionable benefit. How much do we need to know about a preventive screening test before it is recommended as “standard of care?” When do we know enough to either start or stop a service provided to all? How well do we stop a preventive service after it is shown to be ineffective? Preventive care services delivery is the cornerstone of pediatrics. From the newborn visit through adolescence, the American Academy of Pediatrics (AAP) and Bright Futures recommend 31 well-child care visits, each with specific discrete preventive services.4 We are often asked by our trainees in clinic how we decide what services to provide within the limited available time. We were taught by skilled and talented clinicians based on their personal knowledge, experience, and expert opinion about what … Address correspondence to David C. Grossman, MD, MPH, Group Health Cooperative, Group Health Research Institute, 1730 Minor Ave, Ste 1600, Seattle, WA 98101. E-mail: grossman.d{at}ghc.org

The febrile child: how frequent should we investigate for urinary tract infection

Background: Febrile illness in children remains the most common cause of emergency room visit. In many tropical countries where malaria is endemic, children presenting with fever are treated for malaria presumptuously. Current evidence suggests however that malarial parasitaemia in febrile children is declining and the prevalence of other causes of fever apparently on the increase. Therefore, highlighting such causes of fever as urinary tract infection (UTI) is indispensable. This is much so as UTI not only is common in younger children and often neglected but also associated with long term complications. Methods: Children aged 6- 59months with fever of less than 2weeks were consecutively recruited. Each child had both clinical evaluation and preliminary laboratory assessment such as dipstick urinalysis. Further microbiological and radiological evaluations were performed where necessary: blood film for malarial parasite identification and count, cerebrospinal fluid (CSF) analysis and chest X-ray. Results: Of the 303 children 180 (59.4%) were males and 123 were females (40.6%). The mean age was 21.7±14.0months, 54.5% were less than 24months. ARI accounted for 44.6% (mainly tonsillitis, 61%, pneumonia, 27% and otitis media, 12%), while malaria and UTI were observed in 38.3% and 4.6% respectively. Five (35.7%) patients with UTI were males while 9 (64.3%) were females. Their combined mean age was 25.4±18.6months, 57% of these children were less than 24 months old. In 3(21.4%), UTI coexisted with malaria. Conclusions: Acute respiratory infection, malaria and UTI are the three leading causes of fever in children under 5 years. Keywords: Fever, Children, Acute respiratory infection, Malaria, UTI

Comparison of various screening methods for presumptive diagnosis of significant bacteriuria

Background: Urinary tract infection is a common source of bacterial infection among people of any age. Urinalysis is one of the important and useful urological tests for diagnosis of the infection. Microscopic examination of urine, catalase test, and the dipstick urinalyses (leukocyte esterase test and nitrite test) are common tests used for detecting bacteriuria and pyuria. Although culture is the gold standard method for diagnosis of urinary tract infection, the culture is an expensive and time-consuming method. Objective: (1) To compare dipstick urinalysis with microscopic urinalysis, (2) to compare dipstick and microscopic urinalyses results with urine culture results, by calculating performance characteristics of dipstick tests, and (3) to compare catalase test with urine culture results. Materials and Methods: The 1,000 urine specimens were processed by using dipstick and microscopic urinalyses and cultured. Reagent strips reading and microscopic examination were included in laboratory urinalysis in this study. Result: Of 1,000 urine samples of patients, 186 (18.6%) patients revealed urine cultures with significant bacteriuria (105 colonies/mL or greater). Sensitivity and specificity of microscopic urinalysis bacteriuria were 96.77% and 98.52%, respectively. Whereas, in dipstick urinalysis, sensitivity and specificity of nitrite test were 90% and 97% and, in leukocyte esterase test, they were 87% and 95%, respectively. Sensitivity and specificity of catalase test for bacteriuria were 88.63% and 75.86%, respectively. Conclusion: Dipstick test could be used more effectively as office procedure in rural areas where laboratory facility for microscopy and culture is not available for diagnosis of urinary tract infection.

How Sensitive Is Urine Dipstick Analysis in Predicting Urinary Tract Infections in Symptomatic Adults in a Primary Care Setting ?

Background: Urinary tract infection (UTI) is a common clinical problem in the primary care setting. Urine dipstick analysis is a quick, cheap and widely used test to predict UTI in clinically suspected patients. Objective: To evaluate the sensitivity of urine dipstick analysis as a screening test in predicting UTI in symptomatic adults in the primary care setting. Methods: A total of 420 culture-positive urine samples from patients with symptomatic UTI, who had dipstick urinalysis in a primary care center were the materials of this study from March to October 2015. The sensitivity of urine dipstick nitrites (NT), leukocyte esterase (LE) and blood was calculated and compared with positive culture samples either individually or in combination. Results: The sensitivity of dipstick NT alone was the lowest of all tests (20.7%), while LE alone was marginally higher than NT (31.42%), whereas dipstick blood test when considered alone was the highest sensitive (61.9%). In combination, NT and/ or LE were marginally higher than either test alone (41.2%), while NT and/or blood were (64.5%). The highest sensitivity of dipstick is obtained when all the three parameters were considered together (NT and/or LE and/or Blood, sensitivity 81.4%). Conclusion: Dipstick NT, LE, and blood are poor screening tests when used individually. Dipstick sensitivity significantly increases, and it could be considered a good screening test to predict UTI in symptomatic adults in the primary care setting when its three components are considered together. However, negative dipstick analysis should not rule out UTI in symptomatic adults, and urine culture is necessary for accurate diagnosis.

Effect of consuming a purple-fleshed sweet potato beverage on health-related biomarkers and safety parameters in Caucasian subjects with elevated levels of blood pressure and liver function biomarkers: a 4-week, open-label, non-comparative trial.

An open-label study with one treatment arm was conducted to investigate changes in health-related biomarkers (blood pressure and liver enzyme activity) and the safety of 4 weeks of consuming a purple-fleshed sweet potato beverage in Caucasian subjects. Twenty healthy adults, 18–70 years of age, with a body mass index >25 kg/m2, elevated blood pressure and elevated levels of liver function biomarkers consumed two cartons of purple-fleshed sweet potato beverage (125 ml, including 117 mg anthocyanin per carton) daily for 4 weeks. Hematology, serum clinical profile, dipstick urinalysis and blood pressure were determined before consumption, at 2 and 4 weeks of consumption and after a 2-week washout period. A trend was found toward lowering systolic blood pressure during the treatment period (p=0.0590). No significant changes were found in diastolic blood pressure throughout the study period. Systolic blood pressure was significantly lower after 4 weeks of consumption compared with before consumption (p=0.0125) and was significantly higher after the 2-week washout period compared with after consumption (p=0.0496). The serum alanine aminotransferase level significantly increased over time, but aspartate aminotransferase and γ-glutamyltransferase levels stayed within the normal range of reference values. Safety parameters of the blood and urine showed no clinically relevant changes. The consumption of a purple-fleshed sweet potato beverage for 4 weeks resulted in no clinically relevant changes in safety parameters of the blood and urine and showed a trend toward lowering systolic blood pressure.

Robust dipstick urinalysis using a low-cost, micro-volume slipping manifold and mobile phone platform.

We introduce a novel manifold and companion software for dipstick urinalysis that eliminate many of the aspects that are traditionally plagued by user error: precise sample delivery, accurate readout timing, and controlled lighting conditions. The proposed all-acrylic slipping manifold is reusable, reliable, and low in cost. A simple timing mechanism ensures results are read out at the appropriate time. Results are obtained by capturing videos using a mobile phone and by analyzing them using custom-designed software. We show that the results obtained with the proposed device are as accurate and consistent as a properly executed dip-and-wipe method, the industry gold-standard, suggesting the potential for this strategy to enable confident urinalysis testing in home environments.

Screening for kidney disease in an oil producing community in Nigeria: A pilot study.

Petroleum products have been associated with acute and chronic kidney disease. Nigeria is a major oil producing and exporting country. The aim of this study was to screen for kidney disease in an oil producing community in Nigeria. This was a cross-sectional study carried out in Ido, Asari-Toru Local Government Area of Rivers State. All subjects were resident in the town and those aged 18 years and above were eligible. Spot urine samples were collected for dipstick urinalysis, and venous blood was collected for estimation of serum electrolyte, urea, creatinine, and lipid profile. The estimated glomerular filtration rate (eGFR) was calculated using the Cockcroft and Gault formula. A total of 99 participants were screened: 75% were females, over 50% aged above 50 years, and the majority had low socioeconomic status. The mean eGFR of the participants was 80.2 ± 33.3 mL/min/1.73 m 2 , 32.6% of the participants had eGFR <60 mL/min, and 2% had eGFR <30 mL/min. Furthermore, 36.5% of the participants had proteinuria and 29.8% had 1 + proteinuria. There was a significant negative correlation of eGFR with a family history of diabetes mellitus (-0.35, P = 0.016), elevated systolic hypertension (-0.29, P = 0.035), and elevated total cholesterol (-0.23, P = 0.045), but there was a positive correlation with body mass index (0.24, P = 0.018). We conclude that the prevalence of kidney disease was high in the screened population in a Nigerian oil producing community.

Proteinuria Is an Independent Risk Factor for First Incident Stroke in Adults Under Treatment for Hypertension in China.

BackgroundConflicting evidence exists regarding whether reduced estimated glomerular filtration rate (eGFR) and proteinuria are independent risk factors for stroke and its subtypes in hypertensive patients. This study investigated the association of these renal measures with first incident stroke in adults under treatment for hypertension in China.Methods and ResultsThe study included 19 599 adults aged 45 to 75 years who participated in the China Stroke Primary Prevention Trial. Baseline eGFR was calculated using the Chronic Kidney Disease Epidemiology Collaboration creatinine equation. Proteinuria was assessed by qualitative dipstick urinalysis and in a subset by the quantitative albumin–creatinine ratio method. Cox regression analysis was used to examine the effects of eGFR and proteinuria on the risk of first incident stroke. During a median of 4.5 years of follow‐up, a total of 585 first strokes (472 ischemic strokes) were identified. Compared to participants without proteinuria, participants with proteinuria (trace or more by dipstick) had a 35% increased risk of first stroke: the adjusted hazard ratio (HR) (95% CI) was 1.35 (1.09–1.66, P=0.005). The results were robust in subgroup analyses. In a subset with data on proteinuria measured by quantitative albumin–creatinine ratio, a similar association was found. In both independent and combined analyses with proteinuria, eGFR was not significantly associated with stroke.ConclusionsIn adults under treatment for hypertension in China, baseline proteinuria measured by dipstick or quantitative albumin–creatinine ratio, but not reduced eGFR, was found to be an independent risk factor for first incident stroke and ischemic stroke.

The Development and Initial Assessment of a Novel Heart Rate Training Formula

The Development and Initial Assessment of a Novel Heart Rate Training Formula

Proteinuria and Reduced Estimated Glomerular Filtration Rate Independently Predict Risk for Acute Myocardial Infarction: Findings from a Population-Based Study in Keelung, Taiwan.

The aim of this study was to evaluate the independent roles of proteinuria and reduced estimated glomerular filtration rate (GFR) in the development of acute myocardial infarction in a northern Taiwanese population. We conducted a community-based prospective cohort study in Keelung, the northernmost county of Taiwan. A total of 63,129 subjects (63% women) ≥ 20 years of age who had no history of coronary heart disease were recruited and followed-up. Univariate and multivariate proportional hazards regression analysis was performed to assess the association between proteinuria and estimated GFR and the risk of acute myocardial infarction. There were 305 new cases of acute myocardial infarction (114 women and 191 men) documented during a four-year follow-up period. After adjustment of potential confounding covariates, heavier proteinuria (dipstick urinalysis reading 3+) and estimated GFR of less than 60 ml/min/1.73 m(2) independently predicted increased risk of developing acute myocardial infarction. The adjusted hazard ratio (aHR) of heavier proteinuria for occurrence of acute myocardial infarction was 1.85 [95% confidence intervals (CI), 1.17-2.91, p < 0.01] (vs. the reference group: negative dipstick proteinuria). The aHR of estimated GFR of 30-59 ml/min/1.73 m(2) for occurrence of acute myocardial infarction was 2.4 (95% CI, 1.31-4.38, p < 0.01) (vs. the reference group: estimated GFR ≥ 90 ml/ min/1.73 m(2)), and that of estimated GFR of 15-29 ml/min/1.73 m(2) was 5.26 (95% CI, 2.26-12.26, p < 0.01). We demonstrated that both heavier proteinuria and lower estimated GFR are significant independent predictors of developing future acute myocardial infarction in a northern Taiwanese population. Acute myocardial infarction; Estimated glomerular filtration rate; Proteinuria.

Asymptomatic bacteriuria screened by catheterized samples at pregnancy term in women undergoing cesarean delivery

Objective: The objective of this study was to assess the frequency of urinary tract infection (UTI) with urine samples obtained via catheterization among women undergoing cesarean delivery at term pregnancy. Materials and Methods: A cross-sectional study involving 159 women in whom cesarean delivery was conducted at term pregnancy after a regular follow-up from first to third trimester. For screening and diagnosis of UTI during antenatal period, the authors used dipstick test and microscopic urinalysis, and urine culture was used in the presence of symptomatic UTI unresponsive to initial antibiotic therapy. A urine sample was obtained immediately after insertion of Foley catheter for urine dipstick test, microscopic urinalysis, and culture during cesarean delivery. Obstetric and UTI data were recorded. Results: Of 159 pregnant women, 95 (59.8%) did not develop UTI during antenatal care. There was no patient with symptomatic UTI at the admission for cesarean delivery. The authors found UTI with urine dipstick and microscopic urinalysis in 12 patients and of them, four patients had no history of UTI, and all the remaining eight patients had asymptomatic UTI during antenatal followup. UTI according to urine culture was encountered in three patients, two of them had one episode of UTI, and one had two episodes of UTI during antenatal follow-up. Conclusions: After regular antenatal follow-up screening with urine dipstick, microscopic urinalysis, and counseling of pregnant women regarding UTIs, the frequency of bacteriuria decreases considerably during cesarean delivery.

Renal related disorders in concomitant Schistosoma haematobium-Plasmodium falciparum infection among children in a rural community of Nigeria.

Schistosomiasis and malaria are two common parasitic diseases that are co-endemic in resource-poor communities of sub-Saharan Africa. This study aims to assess the effects of single and concomitant Plasmodium falciparum and Schistosoma haematobium infections on two indicators of renal injury in school children in a rural community of Nigeria. A cross-sectional epidemiological survey was carried out on a total of 173 schoolchildren between ages 6 and 18 years (mean age 11.4±2.6 years). Urine and blood samples were collected by standard methods for concurrent microscopic diagnosis of S. haematobium and P. falciparum infections. Urinary blood (hematuria) and protein were determined using a urinalysis dipstick. The prevalence of single infections was 75.1% and 78.2% for S. haematobium and P. falciparum, respectively. A total of 57.1% individuals were infected with the two parasites. The prevalence of hematuria was significantly higher in the co-infection status (63.8%) than in single S. haematobium (52.2%) and P. falciparum (43.7%) infection statuses (p=0.04), while no significant variation was recorded in proteinuria in the three infection statuses (p=0.53). The proportion of children with renal injury associated with the co-infection of these parasites is very high, particularly in young children, who seem to have a higher prevalence of hematuria.

Dipstick Urinalysis in apparently healthy Neonates in Port Harcourt

Dipstick Urinalysis in apparently healthy Neonates in Port Harcourt

Nonalbumin proteinuria predominates in biopsy-proven tenofovir nephrotoxicity

Tenofovir disoproxil fumarate (TDF) nephrotoxicity is characterized by proximal renal tubular injury and dysmorphic mitochondria resulting in proteinuria, orthoglycemic glycosuria, and other markers of proximal tubular dysfunction. The objective of this study was to determine the pattern of proteinuria in patients with biopsy-proven TDF nephrotoxicity. Retrospective chart review. Patients with biopsy-proven TDF nephrotoxicity were identified and their medical charts and biopsy reports were reviewed. Comparison was made with HIV-infected patients not on TDF who underwent kidney biopsy. We identified 43 biopsy-proven cases of TDF nephrotoxicity; mean age 54.7 ± 0.4 years, 53% men, 42% whites. Thirty-seven cases reported proteinuria by dipstick of which only 60% had at least 2+ proteinuria. Twenty-seven patients had urine protein quantified by either 24-h collection or spot urine protein-to-creatinine ratio; median proteinuria was 1742 mg/day [interquartile range (IQR) 1200-2000 mg] and 1667 mg/g creatinine (IQR 851-1967 mg/g), respectively. Ten patients had concurrent urinary albumin measured, with a median 236 mg/g creatinine (IQR 137-343 mg/g). The mean urine albumin-to-urine protein ratio (uAPR) was 0.17 (IQR 0.14-0.19), confirming that TDF nephrotoxicity is primarily associated with nonalbumin proteinuria. Control cases had a uAPR of 0.65 (IQR 0.55-0.79) P < 0.001. Histopathology showed the predominance of proximal tubular injury with characteristic mitochondrial abnormalities. In the largest published cohort of patients with biopsy-proven TDF nephrotoxicity, we show that low uAPR is a reliable feature of this disease. Because of the predominance of nonalbumin proteinuria, dipstick urinalysis may be unreliable in TDF nephrotoxicity.

Cardboard versus sterile containers: more nitrite-positive urinalysis results?

Urinalysis is a frequently performed test that provides valuable information as to the health of individuals. The presence of nitrites in the urine may indicate infection. Antibiotic therapy is commonly started following the results of dipstick urine taken from non-sterile urine samples. This is especially prevalent in men who are immobile, because sterile containers large enough to hold a full bladder of urine are not available (at the author's trust). Urine samples were taken from 25 male A&E patients in a sterile container. Half of each sample was decanted into an ordinary cardboard urine bottle and both samples were then tested using dipstick urinalysis after 1 minute and after 10 minutes to see if there was a difference in the presence of nitrites between the two container types. After 10 minutes, 21 of the 25 samples showed a positive nitrite dipstick in the cardboard container while it remained negative when the urine remained in the sterile container. These results demonstrate that care needs to be taken when collecting urine samples, and the results of dipstick urinalysis should be used with caution depending on the collection method.