Urinary screening tests for early detection of renal diseases in asymptomatic school children and adolescents are important in the detection of silent renal diseases.
The purpose of the study was to determine the prevalence of occult renal diseases by dipstick test (reagent strips) in asymptomatic Nepalese children.
Patients and Methods
A total of 2,243 school children, aged 5–15 years, were screened for urinary abnormalities using dipstick test screening. The children who tested positive in the first screening were re-tested after 2–4 weeks.
In the first screening, 123 children (5.5%) tested positive for isolated hematuria and proteinuria and for combined hematuria and proteinuria. Of these children, 16 (0.71%) cases tested positive in a second screening. Subsequently, 1 child from the secondary screening group was lost to follow up, 5 tested normal and 10 revealed abnormalities. Glomerulonephritis was the most commonly detected disorder (50%).
Urinary screening was found to be useful in identifying occult renal diseases in asymptomatic children. Urinary screening would therefore not only help in early detection but also in the prevention of the deterioration of renal function later in life.
Urinary Screening; School Children; Renal Diseases
Recent studies on Vietnamese children have shown that kidney diseases are not detected early enough to prevent chronic renal failure. The dipstick test is a simple and useful tool for detecting urinary abnormalities, especially in isolated or remote areas of Vietnam, where children have limited access to health care.
This cross-sectional study was conducted in 2011 at seven kindergartens in Can Gio district, Ho Chi Minh City, Vietnam. Two thousand and twelve children, aged 3 to 5, were enrolled. Morning mid-stream urine samples were examined by dipstick. Children with abnormal findings were re-examined with a second dipstick and underwent further investigations.
Urinalysis was available for 1,032 boys and 980 girls. Mean age was 4.4 ± 0.8 years. Urinary abnormalities were detected in 108 (5.5%) of the subjects. Among them, nitrituria and leucocyturia accounted for more than 50%. Positive fractions of proteinuria, hematuria, nitrituria, leucocyturia, and combined nitrituria and leucocyturia after two dipsticks were 0.1%, 0.1%, 2%, 1% and 0.3%, respectively. Abnormal findings were more common in girls than boys (p < 0.001), and higher in communes with very low (< 50 persons/km2) population density (14.3% vs 4.1%, p < 0.001). A renal ultrasound detected four cases of hydronephrosis and one case of duplication of ureter.
The prevalence of urinary abnormalities in asymptomatic children in South Vietnam demonstrates the need for hygiene education among parents. Training for dipstick usage for all medical staff at health stations, especially in remote areas and in places with very low population density, is also clearly necessary. Routine urinalysis can be set up if a close control is conducted at locations.
Chronic kidney disease; Dipstick; Urinary screening; Can Gio; Vietnam
There is no evidence surrounding the benefits, effects or clinical outcomes treating asymptomatic urinary tract colonisation. A series of 558 patients undergoing elective admission for orthopaedic surgery were recruited prior to surgery and were screened for urinary tract infection (UTI). Patients had their urine dipstick tested and positive samples were sent for culture and microscopy. Patients with a positive urine culture were treated with antibiotics prior to surgery; 85% of dipsticks tested were positive, while only 7% of the urine samples were culture positive. Over 36% of patients with a pre-operative UTI show some form of post-operative delayed wound healing or confirmed infection versus 16% in the other subgroup giving a relative risk of wound complications of 2:1 (p < 0.02). We have established that patients who present to pre-admission with urinary tract colonisation are a high risk subgroup for wound infection post-operatively.
It is known that there is significant morbidity associated with urinary tract infection and with renal dysfunction in sickle cell disease (SCD). However, it is not known if there are potential adverse outcomes associated with asymptomatic bacteriuria (ASB) infections in sickle cell disease if left untreated. This study was undertaken to determine the prevalence of ASB, in a cohort of patients with SCD.
This is a cross-sectional study of patients in the Jamaican Sickle Cell Cohort. Aseptically collected mid-stream urine (MSU) samples were obtained from 266 patients for urinalysis, culture and sensitivity analysis. Proteinuria was measured by urine dipsticks. Individuals with abnormal urine culture results had repeat urine culture. Serum creatinine was measured and steady state haematology and uric acid concentrations were obtained from clinical records. This was completed at a primary care health clinic dedicated to sickle cell diseases in Kingston, Jamaica. There were 133 males and 133 females in the sample studied. The mean age (mean ± sd) of participants was 26.6 ± 2.5 years. The main outcome measures were the culture of ≥ 105 colony forming units of a urinary tract pathogen per milliliter of urine from a MSU specimen on a single occasion (probable ASB) or on consecutive occasions (confirmed ASB).
Of the 266 urines collected, 234 were sterile and 29 had significant bacteriuria yielding a prevalence of probable ASB of 10.9% (29/266). Fourteen patients had confirmed ASB (prevalence 5.3%) of which 13 had pyuria. Controlling for genotype, females were 14.7 times more likely to have confirmed ASB compared to males (95%CI 1.8 to 121.0). The number of recorded visits for symptomatic UTI was increased by a factor of 2.5 (95% CI 1.4 to 4.5, p < 0.005) but serum creatinine, uric acid and haematology values were not different in patients with confirmed ASB compared with those with sterile urine. There was no association with history of gram negative sepsis.
ASB is a significant problem in individuals with SCD and may be the source of pathogens in UTI. However, further research is needed to determine the clinical significance of ASB in SCD.
Haematuria is one of the clinical manifestations of sickle cell nephropathy. Although dipstick urinalysis detects haemoglobin and by extension haematuria; it does not confirm haematuria. Urine sediment microscopy confirms haematuria and constitutes a non-invasive “renal biopsy”. The need to correlate dipstick urinalysis and urine sediment microscopy findings becomes important because of the cheapness, quickness and simplicity of the former procedure.
Dipstick urinalysis and urine sediment microscopy were carried (both on first contact and a month after) among consecutive steady state sickle cell anaemia children attending sickle cell clinic at the University of Ilorin Teaching Hospital between October 2004 and July 2005.
A total of 75 sickle cell anemia children aged between 1-17 years met the inclusion criteria. Haematuria was found in 12 children (16.0%) and persistent haematuria in 10 children 13.3%. Age and gender did not have significant relationship with haematuria both at first contact (p values 0.087 and 0.654 respectively) and at follow-up (p values 0.075 and 0.630 respectively). Eumorphic haematuria was confirmed in all the children with persistent haematuria with Pearson correlation +0.623 and significant p value of 0.000.
The study has revealed a direct significant correlation for haematuria detected on dipstick urinalysis and at urine sediment microscopy. It may therefore be inferred that dipstick urinalysis is an easy and readily available tool for the screening of haematuria among children with sickle cell anaemia and should therefore be done routinely at the sickle cell clinics.
Sickle cell nephropathy; children; haematuria; dipstick urinalysis; urine sediment microscopy
OBJECTIVE--To investigate the prevalence and relevance of dipstick haematuria in a group of men in the community. DESIGN--Prospective study of elderly men invited to attend a health centre for urine screening as part of a health check. SETTING--An inner city health centre in Leeds. SUBJECTS--578 Of 855 men aged 60-85 responding to an invitation to participate. INTERVENTIONS--The subjects had their urine tested with a dipstick (Multistix) for the presence of blood and then tested their urine once a week for the next 10 weeks. Those with one or more positive test results were offered full urological investigation. MAIN OUTCOME MEASURE--The prevalence of urological disease in those subjects with dipstick haematuria. RESULTS--78 Men (13%) had dipstick haematuria on a single test and a further 54 (9%) had evidence of dipstick haematuria when testing their urine once a week during a subsequent 10 week period. Investigation of 87 men disclosed urological disease in 45, including four with a bladder tumour and seven with epithelial dysplasia. CONCLUSION--Dipstick haematuria is a common incidental finding in men over 60 and is associated with appreciable urological disease. The introduction of less invasive methods of investigation, particularly flexible cystoscopy and ultrasonography, has made investigation of these patients simple and safe and makes screening for bladder cancer in the community more feasible.
Dipsticks are one of the most commonly used near-patient tests in primary care, but few clinical or dipstick algorithms have been rigorously developed.
To confirm whether previously documented clinical and dipstick variables and algorithms predict laboratory diagnosis of urinary tract infection (UTI).
Design of study
A total of 434 adult females with suspected lower UTI had bacteriuria assessed using the European Urinalysis Guidelines.
Sixty-six per cent of patients had confirmed UTI. The predictive values of nitrite, leucocyte esterase (+ or greater), and blood (haemolysed trace or greater) were confirmed (independent multivariate odds ratios = 5.6, 3.5, and 2.1 respectively). The previously developed dipstick rule — based on presence of nitrite, or both leucocytes and blood — was moderately sensitive (75%) but less specific (66%; positive predictive value [PPV] 81%, negative predictive value [NPV] 57%). Predictive values were improved by varying the cut-off point: NPV was 76% for all three dipstick results being negative; the PPV was 92% for having nitrite and either blood or leucocyte esterase. Urine offensive smell was not found to be predictive in this sample; for a clinical score using the remaining three predictive clinical features (urine cloudiness, dysuria, and nocturia), NPV was 67% for none of the features, and PPV was 82% for three features.
A clinical score is of limited value in increasing diagnostic precision. Dipstick results can modestly improve diagnostic precision but poorly rule out infection. Clinicians need strategies to take account of poor NPVs.
algorithms, clinical scoring; diagnosis, urinary tract infection; primary care; urinalysis
Midstream urine samples were examined by phase-contrast microscopy before and immediately after 48 subjects participated in a long-distance run. Minor abnormalities were found in six samples before exercise. Eighteen subjects developed proteinuria and five haematuria on dipstick testing after exercise. Forty-four subjects had increased urinary red-cell counts after exercise; of these, 33 had counts above the normal range (800/ml). In all subjects urinary red cells were dysmorphic both before and after exercise, indicating a glomerular source. Ten subjects developed red-cell casts and 42 showed an increase in hyaline and hyaline-granular casts after exercise. There were modest increases in urinary white-cell counts in 35 subjects but little change in urine pH or osmolality with exercise. This study confirms that urinary red-cell counts commonly increase appreciably after exercise. The dysmorphic appearance of the red cells together with the presence of red-cell casts indicates a glomerular source for this common form of exercise haematuria.
Microalbuminuria has been reported to be a precursor of HIV related renal disease, which if detected early and coupled with appropriate intervention may slow or retard the progress of the disease. One hundred and seventy-eight HIV infected children aged 15 years and below were recruited from the Paediatric Infectious Disease Clinic of Aminu Kano Teaching Hospital (AKTH), Kano, to determine the prevalence of persistent microalbuminuria using the albumin creatinine ratio (ACR). Early morning urine samples and spot urine samples were analyzed using a dipstick specific for microalbumin. Those who tested positive had their samples reanalyzed in the laboratory using immunometric assay and Jaffe reaction method for albumin and creatinine, respectively. Patients that had ACR of 30–300 mg/g were said to have microalbuminuria and had their urine samples retested after 6 to 8 weeks. Twelve children (6.7%) had persistent microalbuminuria and had a mean age of 7.5 ± 3.3 years, with a male to female ratio of 1 : 1. There was no significant relationship between the finding of microalbuminuria and age, sex, duration of infection, and the use of highly active antiretroviral therapy. Periodic screening for microalbuminuria using albumin specific dipstick should be considered for children with HIV infection.
Few studies have evaluated dipstick urinalysis for elderly and practically none present confidence intervals. Furthermore, most previous studies combine all bacteria species in a "positive culture". Thus, their evaluation may be inappropriate due to Yule-Simpson's paradox. The aim of this study was to evaluate diagnostic accuracy of dipstick urinalysis for the elderly in nursing homes.
In this cross-sectional study voided urine specimens were collected from 651 elderly individuals in nursing homes. Dipstick urinalysis for nitrite, leukocyte esterase and urine culture were performed. Sensitivity, specificity, positive and negative predictive values with 95% confidence intervals were calculated. Visual readings were compared to readings with a urine chemistry analyzer.
207/651 (32%) of urine cultures showed growth of a potentially pathogenic bacterium. Combining the two dipsticks improved test characteristics slightly compared to using only one of the dipsticks. When both dipsticks are negative, presence of potentially pathogenic bacteria can be ruled out with a negative predictive value of 88 (84–92)%. Visual and analyzer readings had acceptable agreement.
When investigating for bacteriuria in elderly people at nursing homes we suggest nitrite and leukocyte esterase dipstick be combined. There are no clinically relevant differences between visual and analyzer dipstick readings. When dipstick urinalysis for nitrite and leukocyte esterase are both negative it is unlikely that the urine culture will show growth of potentially pathogenic bacteria and in a patient with an uncomplicated illness further testing is unnecessary.
AIM—To evaluate the reliability of
dipstick measurements of urine specific gravity (U-SG).
METHODS—Fresh urine specimens were
tested for urine pH and osmolality (U-pH, U-Osm) by a pH meter and an
osmometer, and for U-SG by three different methods (refractometry,
automatic readout of a dipstick (Clinitek-50), and (visual) change of
colour of the dipstick).
RESULTS—The correlations between
the visual U-SG dipstick measurements and U-SG determined by a
refractometer and the comparison of Clinitek®-50 dipstick
U-SG measurements with U-Osm were less than optimal, showing very wide
scatter of values. Only the U-SG refractometer values and U-Osm had a
good linear correlation. The tested dipstick was unreliable for the
bedside determination of U-SG, even after correction for U-pH, as
recommended by the manufacturer.
CONCLUSIONS—Among the bedside
determinations, only refractometry gives reliable U-SG results.
Dipstick U-SG measurements should be abandoned.
BACKGROUND AND OBJECTIVES--The leukocyte esterase (LE) strip is a useful tool for the screening of men with urethritis. In developing countries, where laboratory facilities are limited, and sexually transmitted diseases endemic, simple and inexpensive diagnostic tests which perform well, would be of great value. METHODS--Men presenting with urethritis to a referral clinic for sexually transmitted diseases in Nairobi, Kenya participated in this cohort analytical study. First-void urine was collected for LE dipstick testing as part of the diagnostic work-up. The results of the dipstick measurement were compared with the laboratory detection of Chlamydia trachomatis and Neisseria gonorrhoeae. RESULTS--Of 200 men with symptoms of urethritis, 33 (17%) had a pathogen detected from the urethra or the urine. Chlamydia was detected in urine by PCR in 22 (11%), and gonorrhoea was cultured from the urethra in 11 (6%). Esterase activity (trace or greater) had a sensitivity of 76%, a specificity of 80%, a positive predictive value of 42% and a negative predictive value of 94% for the presence of chlamydia or gonorrhoea. CONCLUSIONS--The use of the LE dipstick for the screening of men with symptomatic urethritis can improve diagnostic accuracy and reduce the amount of empiric antimicrobial therapy. The low detection rate of chlamydia in these men with a clinical diagnosis of nongonococcal urethritis needs further study.
The protein creatinine index in early morning and random urine specimens was compared with the 24 hour urinary excretion of protein in normal subjects and outpatients with abnormal proteinuria. A protein creatinine index (defined as (mg protein/1 divided by creatinine mmol/1) times 10) below 125 in a random specimen excluded abnormal proteinuria, whereas an index of more than 136 indicated the presence of pathological proteinuria. The index for random specimens provided a useful semiquantitative assessment of the 24 hour excretion of protein (mg protein/24 hours), but the index for early morning specimens was less reliable. Errors with Albustix were partly due to intra and inter observer variations in the interpretation of the colour formed when compared with the chart provided. It is proposed that the protein creatinine index on random urine samples should be used to supplement dipsticks in screening for proteinuria in cases where misclassification would be serious.
During the statutory medical examination on entrance to primary school 943 5-year-old girls were screened for asymptomatic bacteriuria. A prevalence of 2·1% was found. None of the 20 children with asymptomatic bacteriuria was recognized by the parents as having a urinary infection, though 14 of them had symptoms of lower urinary tract infection. In 16 of the children with bacteriuria either the intravenous pyelogram or the micturating cystogram was abnormal. In 12 the height and weight were below the 25th percentile, and in this group the most severe radiological changes were found.
Though the significance of asymptomatic bacteriuria is unknown, these results confirm that in this age group it is often associated with a urinary tract abnormality.
1000 children between the ages of 3 months and 5 years were screened for urinary tract infection using a dipslide technique. Significant or doubtful cultures were obtained in 13%, the rate being highest (47%) in children below the age of one year. Higher rates were obtained in girls (16%) than in boys (11%). After serial dipslide and urine examinations, 9 children were considered to have a urinary tract infection. 2 had radiological abnormalities.
In view of the uncertainty regarding the effect of treatment on the long-term prognosis of children with asymptomatic bacteriuria, it is suggested that the results of controlled studies should be awaited before any recommendation is made concerning the urinary screening of this age group.
In the emergency department, hyperglycemic patients are screened for diabetic ketoacidosis (DKA) via a urine dipstick. In this prospective study, we compared the test characteristics of point-of-care β-hydroxybutyrate (β-OHB) analysis with the urine dipstick.
RESEARCH DESIGN AND METHODS
Emergency-department patients with blood glucose ≥250 mg/dL had urine dipstick, chemistry panel, venous blood gas, and capillary β-OHB measurements. DKA was diagnosed according to American Diabetes Association criteria.
Of 516 hyperglycemic subjects, 54 had DKA. The urine dipstick had a sensitivity of 98.1% (95% CI 90.1–100), a specificity of 35.1% (30.7–39.6), a positive predictive value of 15% (11.5–19.2), and a negative predictive value of 99.4% (96.6–100) for DKA. Using the manufacturer-suggested cutoff of >1.5 mmol/L, β-OHB had a sensitivity of 98.1% (90.1–100), a specificity of 78.6% (74.5–82.2), a positive predictive value of 34.9% (27.3–43), and a negative predictive value of 99.7% (98.5–100) for DKA.
Point-of-care β-OHB and the urine dipstick are equally sensitive for detecting DKA (98.1%). However, β-OHB is more specific (78.6 vs. 35.1%), offering the potential to significantly reduce unnecessary DKA work-ups among hyperglycemic patients in the emergency department.
A dipstick assay, based on Leishmania infantum antigen, for the rapid detection of Leishmania-specific antibodies in canine serum samples was developed and evaluated. After determination of optimal dipstick test conditions, test performance was compared with two existing serological tests, i.e., the direct agglutination test (DAT) and the fast agglutination screening test (FAST). In the present study the dipstick test had a sensitivity of 99.2% and a specificity of 87.9%. The DAT had a sensitivity of 97.7% and a specificity of 95.2%, whereas the FAST had also a sensitivity of 97.7% and a specificity of 93.0%. High degrees of agreement were observed between the dipstick test and DAT (93.7%; κ value, 0.86), between the dipstick test and FAST (91.8%; κ value, 0.82), and between the DAT and FAST (95.2%; κ value, 0.90). The high sensitivity and ease of performance make the dipstick test very suitable for surveillance surveys.
Urinary tract infection (UTI) is one of the most common types of infection. Currently, diagnosis is primarily based on microbiologic culture, which is time- and labor-consuming. The aim of this study was to assess the diagnostic accuracy of urinalysis results from UriSed (77 Electronica, Budapest, Hungary), an automated microscopic image-based sediment analyzer, in predicting positive urine cultures.
Materials and methods:
We examined a total of 384 urine specimens from hospitalized patients and outpatients attending our hospital on the same day for urinalysis, dipstick tests and semi-quantitative urine culture. The urinalysis results were compared with those of conventional semi-quantitative urine culture.
Of 384 urinary specimens, 68 were positive for bacteriuria by culture, and were thus considered true positives. Comparison of these results with those obtained from the UriSed analyzer indicated that the analyzer had a specificity of 91.1%, a sensitivity of 47.0%, a positive predictive value (PPV) of 53.3% (95% confidence interval (CI) = 40.8–65.3), and a negative predictive value (NPV) of 88.8% (95% Cl = 85.0–91.8%). The accuracy was 83.3% when the urine leukocyte parameter was used, 76.8% when bacteriuria analysis of urinary sediment was used, and 85.1% when the bacteriuria and leukocyturia parameters were combined. The presence of nitrite was the best indicator of culture positivity (99.3% specificity) but had a negative likelihood ratio of 0.7, indicating that it was not a reliable clinical test.
Although the specificity of the UriSed analyzer was within acceptable limits, the sensitivity value was low. Thus, UriSed urinalysis results do not accurately predict the outcome of culture.
urinalysis; bacteriuria; sensitivity; specificity; urinary tract infection
Many serious and potentially treatable diseases of the urinary tract may have haematuria as their only manifestation. However, asymptomatic microscopic haematuria detected by dipstick testing may be seen in up to 16% of screening populations. The great majority of such cases will have no sinister underlying cause, particularly in those under 40 years of age, and so the schedule of further investigations, some of which may be invasive, time-consuming and expensive, needs to be rationalised. In addition, the increasing popularity of 'fast track' clinics for the investigation of haematuria enhances the need for a clear strategy of investigation. Analysis of the epidemiology of asymptomatic haematuria and its causes combined with a consideration of the risk-benefit profile of the available investigations, makes it possible to set out an algorithm for the initial management of this common finding. Careful clinical assessment and basic laboratory tests for renal function, analysis of the urinary sediment and cytological examination of the urine are followed by ultrasound and plain radiography of the urinary tract. Flexible cystoscopy under local anaesthetic is central to the algorithm in patients of all ages. The importance of a nephrological opinion and consideration of renal biopsy, especially in younger patients with other evidence of glomerular disease, is stressed. The role of intravenous urography in excluding pathology of the upper urinary tract, especially in patients over the age of 40, is also considered.
Little work has been done to assess the quality of health care and the use of evidence-based methods by occupational physicians in Belgium. Therefore, the main objective is to describe one aspect of occupational health assessments, namely the common use of dipstick urinalysis, and to compare the current practice with international guidelines.
A self-administered questionnaire was mailed to 211 members of the Scientific Association of Occupational Medicine in the Dutch speaking part of Belgium.
A total of 120 occupational physicians responded, giving a response rate of 57%. Dipstick urinalysis was a routine investigation for the vast majority of physicians (69%). All test strips screened for protein and in 90% also for blood. Occupational health services offered clinical tests to satisfy customer wants as international guidelines do not recommend screening for haematuria and proteinuria in asymptomatic adults. A lack of knowledge concerning positive testing and referral criteria was demonstrated in almost half of the study participants.
Belgian occupational physicians still routinely perform dipstick testing although there is no evidence to support this screening in healthy workers. To practice evidence-based medicine, occupational physicians need more instruction and training. Development and implementation of more guidelines is not only of use for the individual practitioner, it may also enhance professionalization and efficiency of occupational health care.
Evidence-based practice; Occupational health; Guidelines; Health surveillance
BACKGROUND. Microalbuminuria may predict proteinuria and increased mortality in non-insulin dependent diabetic patients. Early detection of microalbuminuria may therefore be essential. AIM. The primary objective of this study was to describe the association between the presence of albuminuria in diabetic patients as detected by general practitioners using conventional reagent strip dipstick tests for albumin, and the urinary albumin concentration as measured in a hospital laboratory. METHOD. A total of 675 newly diagnosed diabetic patients aged 40 years or over were included in the Danish study, diabetes care in general practice. Data for urinary albumin concentration from a morning urine sample and the results of three consecutive dipstick tests for albumin were collected for 417 patients. RESULTS. When defining elevated urinary albumin concentration as 200 mg l-1 or more (proteinuria) the finding of at least one positive test out of the three dipstick tests for albumin had a diagnostic sensitivity of 73% and a specificity of 89%. When the microalbuminuric range (15.0 to 199.9 mg l-1) was added to the definition of renal involvement, the sensitivity of the dipstick test became as low as 28% with a specificity of 96%. CONCLUSION. It is essential for general practitioners to be able to identify proteinuric patients. To achieve this by means of the conventional dipstick test, general practice procedures need to be improved. As it is becoming increasingly well-documented that microalbuminuric non-insulin dependent diabetic patients may benefit from pharmacological treatment of even slight arterial hypertension and heart failure, it seems reasonable to suggest that the use of dipsticks for albumin in general practice be replaced by laboratory quantitative determination of urinary albumin concentration in a morning urine sample.
A total of 128 previously frozen first-void urine (FVU) specimens from selected asymptomatic men were centrifuged and tested by three Chlamydia trachomatis rapid antigen detection tests and with a leukocyte esterase (LE) dipstick. When the results were compared to those of a reference standard of positivity determined by the Chlamydiazyme enzyme immunoassay as confirmed by a blocking assay, the sensitivities of the Testpack Chlamydia (Abbott), Clearview Chlamydia (Unipath), and Surecell Chlamydia (Kodak) tests and the LE dipstick test were 76.4, 76.4, 67.3, and 88.6%, respectively. Use of the ligase chain reaction (LCR), whose results were confirmed by direct fluorescent-antibody staining of elementary bodies, as the reference standard reduced the sensitivities to 70.9, 67.7, 62.9, and 87.5%, respectively. The specificities by use of LCR as the reference standard were 95.5, 95.5, 100, and 92.4%, respectively. These rapid chlamydial antigen tests performed reasonably well with FVU specimens, but the simple LE dipstick test, which had the highest sensitivity, would have enabled treatment of the greatest number of infected male patients.
Background: Preeclampsia is a serious complication of pregnancy, and it is vital to diagnosis the condition as early as possible. Proteinuria is an important symptom of preeclampsia, and repeated urine analysis to screen for the condition is part of the standard antenatal care. The purpose of this study was to determine the correlation between 4- and 24-hour urine total protein values to examine whether the 4-hour urine samples could be used for the diagnosis of proteinuria in hypertensive disorders of pregnancy.
Methods: A cross-sectional study was performed on 110 pregnant (after gestational week 20 of pregnancy) patients who were hypertensive (blood pressure ≥140/90 mmHg) and had proteinuria as defined by positive urinary protein of at least 1+ in dipstick. Patients' urine samples were collected over 24 hours; the first 4 hours were collected separately from the next 20-hours. Patients, who did not collect the 24-hour urine, were excluded from the study. One hundred patients met the criteria, and were included in the study. The urine volume, total protein and creatinine levels of 4- and 24-hours samples were measured. The correlation between 4-hour and 24-hour samples was examined using Pearson correlation test.
Results: Of the 100 patients, 42 had no proteinuria, 44 had mild proteinuria, and 14 had severe proteinuria. The urine protein values of 4-hour samples correlated with those of the 24-hours samples for patients with mild and severe forms of the disease (P<0.001, r=0.86).
Conclusion: This study showed there was a correlation between 4-hour and 24-hour urine proteins. The finding indicates that a random 4-hour sample might be used for the initial assessment of proteinuria.
Preeclampsia; proteinuria; hypertension in pregnancy
Many studies have evaluated the accuracy of dipstick tests as rapid detectors of bacteriuria and urinary tract infections (UTI). The lack of an adequate explanation for the heterogeneity of the dipstick accuracy stimulates an ongoing debate. The objective of the present meta-analysis was to summarise the available evidence on the diagnostic accuracy of the urine dipstick test, taking into account various pre-defined potential sources of heterogeneity.
Literature from 1990 through 1999 was searched in Medline and Embase, and by reference tracking. Selected publications should be concerned with the diagnosis of bacteriuria or urinary tract infections, investigate the use of dipstick tests for nitrites and/or leukocyte esterase, and present empirical data. A checklist was used to assess methodological quality.
70 publications were included. Accuracy of nitrites was high in pregnant women (Diagnostic Odds Ratio = 165) and elderly people (DOR = 108). Positive predictive values were ≥80% in elderly and in family medicine. Accuracy of leukocyte-esterase was high in studies in urology patients (DOR = 276). Sensitivities were highest in family medicine (86%). Negative predictive values were high in both tests in all patient groups and settings, except for in family medicine. The combination of both test results showed an important increase in sensitivity. Accuracy was high in studies in urology patients (DOR = 52), in children (DOR = 46), and if clinical information was present (DOR = 28). Sensitivity was highest in studies carried out in family medicine (90%). Predictive values of combinations of positive test results were low in all other situations.
Overall, this review demonstrates that the urine dipstick test alone seems to be useful in all populations to exclude the presence of infection if the results of both nitrites and leukocyte-esterase are negative. Sensitivities of the combination of both tests vary between 68 and 88% in different patient groups, but positive test results have to be confirmed. Although the combination of positive test results is very sensitive in family practice, the usefulness of the dipstick test alone to rule in infection remains doubtful, even with high pre-test probabilities.
OBJECTIVE--To evaluate the first void urine (FVU) specimen in screening for urethritis and its microbial aetiologies in a male African population in which urinary schistosomiasis is also prevalent. PATIENTS AND METHODS--Two hundred and forty eight males aged 15-54 years provided FVU specimens: 55 patients from a clinic for sexually transmitted diseases (STD), 151 patients from a medical outpatient clinic and 42 villagers from an area of high endemicity for S haematobium. Specimens were tested for leucocyte esterase (LE) using a dipstick (Nephur-Test+Leuco, Boehringer-Mannheim France SA). Ova of S haematobium were sought in terminal urine samples from all subjects. For all STD patients, and all medical outpatients with a positive LE test, urine and urethral swabs were tested for Chlamydia trachomatis antigen, and urethral swabs were tested for Neisseria gonorrhoeae by gram stain and isolation. RESULTS--The prevalence of LE positivity was 38/41 in STD patients with urethral signs or symptoms (93%), 5/14 among other STD patients (36%), 21/151 among medical outpatients (15%) and 13/42 among villagers (31%). As a screening test for urethral infection (detection of gonorrhoea or chlamydia and/or > or = 5 polymorphs per high power field on gram stain) the LE test had a sensitivity of 94% and a specificity of 53% among STD patients. Of 24 STD patients with gonococcal or chlamydial infection, 23 had a positive LE test (96%). Among general medical outpatients, 12 of 22 with a positive LE test had either conventionally defined urethritis or gonococcal or chlamydial infection, giving a positive predictive value of 55% for the LE test in this group. Of 18 subjects in all groups with urinary schistosomiasis nine had a positive LE test (50%), although three of these also had gonorrhoea. Chlamydial antigen was detected in the FVU specimen of all six subjects in whom it was detected in a urethral swab, and in an additional three subjects in the outpatient group. CONCLUSIONS--The FVU, which is an easily collected and non-invasive specimen, can provide valuable information on the prevalence of urethritis and on its microbial aetiology among the general male population in African countries.