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PubMed1990

Significance of a positive urine group B streptococcal latex agglutination test in neonates.

We assessed the clinical significance of a reactive urine latex agglutination (LA) test in neonates without bacteriologically confirmed group B streptococcal (GBS) infection. In a retrospective review of a 3 1/2-month period, during which 367 urine specimens from newborn infants evaluated for suspected sepsis were tested by LA, 25 infants (6.9%) with sterile blood cultures but positive urine LA test results were compared with a control group of 112 infants with both blood cultures and urine LA test results negative for GBS. When the data were studied with stepwise discriminant analysis, the only variables significantly associated with a positive urine LA test result were immature to total neutrophil ratios greater than or equal to 0.16 at 0 and 12 hours. The influence of mucosal GBS colonization on urine LA test results was then investigated prospectively in 98 healthy infants (83 born to mothers colonized with GBS and 15 born to mothers with negative GBS cultures). Eight (8.2%) of the infants studied, or 8 of 52 (15.4%) infants colonized with GBS, had a positive urine LA test result. GBS was isolated from urine cultures of all infants with a positive urine LA test result. A positive urine LA test result was associated with positive GBS rectal and vaginal cultures and with increased density of colonization at those sites. We conclude that contamination of bag specimens of urine with GBS from perineal and rectal colonization may produce a positive urine LA test result in an infant with no systemic sign of infection.

Antigens, Bacterial↗
PubMed1997

Concentrations of specific epithelial growth factors in the urine of interstitial cystitis patients and controls.

PURPOSE: Interstitial cystitis (IC) is a chronic bladder disease for which the etiology is unknown. Because the bladder epithelium is often abnormal in IC, we determined whether the levels of specific urine growth factors postulated to be important for bladder epithelial proliferation are altered in IC. MATERIALS AND METHODS: ELISAs were used to determine levels of epidermal growth factor (EGF), insulin-like growth factor 1 (IGF1), insulin-like growth factor binding protein 3 (IGFBP3), and heparin binding epidermal growth factor-like growth factor (HB-EGF) in urine specimens from women with IC, asymptomatic women without bladder disease, and women with bacterial cystitis. RESULTS: Urine HB-EGF levels were specifically and significantly decreased in IC patients as compared to asymptomatic controls or patients with bacterial cystitis, whether expressed as concentration (amount per volume of urine) or the amount relative to urine creatinine in each specimen. In contrast, urine EGF, IGF1, and IGFBP3 levels were all significantly elevated in IC patients compared to asymptomatic controls. Further, the amounts of urine EGF and IGF1 were also elevated in IC patients as compared to patients with bacterial cystitis, and urine IGFBP3 levels were significantly elevated when expressed per milligram of urine creatinine. CONCLUSIONS: These findings indicate that complex changes in the levels of urine epithelial cell growth factors (EGF, IGF1, and HB-EGF) and a growth factor binding protein (IGFBP3) are associated with IC. While EGF, IGF1, and IGFBP3 levels are either the same or increased in the urine of IC patients as compared to patients with bacterial cystitis or asymptomatic controls, HB-EGF levels are significantly decreased in the urine of IC patients. Understanding the reasons for these changes may lead to understanding the pathogenesis of this disorder.

Adult↗
PubMed2002

Erythropoietin concentrations and isoforms in urine of anonymous Olympic athletes during the Nagano Olympic Games.

The ordinary doping control urine samples of 36 anonymous participants (cross-country skiers, biathlon athletes, and curling athletes) of the 1998 Nagano Olympic Games were analyzed for erythropoietin and erythropoietin isoforms. The urine erythropoietin concentration (IU/l) was determined with a competitive radioimmunoassay method and the isoforms were studied by electrophoresis and given as milli albumin mobility units (mAMU). Erythropoietin was detectable in 23 out of 36 specimens (64%). The biathlon and curling athletes had similar urine concentration of erythropoietin. The group of 16 cross-country skiers had significantly (P < 0.05) increased urine concentration of erythropoietin as compared to curling athletes and four of them had urine erythropoietin concentrations between 3.6 and 5.1 IU/l. The electrophoretic mobility of erythropoietin was determined in all eight samples with urine concentration of erythropoietin of more than 2 (range 2.1-5.1) IU/l. No single urine specimen with a median erythropoietin electrophoretic mobility below the cut-off level of 670 mAMU (indicative of doping with recombinant erythropoietin) was registered. Erythropoietin in urine was detected in 71% and the isoforms of Epo characterized in 29% of the anonymous Olympic endurance athletes. The urine concentration of erythropoietin in the biathlon and curling athletes were similar to those of non-athletes. The group of cross-country skiers had higher levels of erythropoietin in urine. These higher levels of urine erythropoietin in cross-country skiers are partly due to more concentrated urine specimens.

Biomarkers↗
PubMed2002

Plasma and urine levels of urinary trypsin inhibitor in patients with acute and fulminant hepatitis.

BACKGROUND AND AIM: Urinary trypsin inhibitor (UTI) is synthesized by hepatocytes and excreted into urine. Plasma and urine UTI levels have been measured to evaluate whether these levels may be useful markers in various pathological conditions. However, there has been no study on plasma and urine UTI levels in patients with acute liver diseases. The aim of the present study was to evaluate plasma and urine UTI levels and their relationship with the severity of hepatic damage in patients with acute liver diseases. METHODS: Plasma and urine UTI levels were measured by newly developed enzyme-linked immunosorbent assay in 15 patients with acute hepatitis (AH), 12 patients with acute severe hepatitis (ASH) and 10 patients with fulminant hepatitis (FH), as assessed on admission. The serial changes in plasma and urine UTI were also observed in some patients with AH and ASH. RESULTS: Plasma UTI levels (U/mL, median [25-75th percentile]) were: 11.0, (9.5-16.1) in patients with AH; 7.8 (5.6-11.5) in those with ASH; 6.5 (4.0-9.5) in patients with FH; and 9.7 (7.3-11.0) in normal controls. Plasma UTI levels in patients with FH were significantly lower than in those with AH. Plasma UTI levels showed significant positive correlations with the levels of prothrombin time (PT), hepaplastin test, antithrombin III, alpha2-plasmin inhibitor, plasminogen (Plg) and fibrinogen. After the recovery of liver dysfunction, increased plasma UTI levels in patients with AH were decreased, whereas previously decreased plasma UTI levels in patients with ASH were increased. Urine UTI levels were significantly increased in patients with AH compared with those of normal controls. In patients with ASH and FH, urine UTI levels were increased but not significantly. Urine UTI levels significantly positively correlated with PT and Plg. After the recovery of liver dysfunction, previously increased urine UTI levels in patients with AH were decreased. The correlation between plasma UTI and urine UTI levels was not significant. CONCLUSIONS: The findings of the present study suggested that the levels of plasma and urine UTI changed in patients with AH and were closely related to the abnormalities of coagulo-fibrinolysis, including PT. Further studies are needed to clarify whether these levels may be useful markers to predict the prognosis of acute hepatitis.

Acute Disease↗
PubMed1998

Inter-alpha-inhibitor in urine and calcium oxalate urinary crystals.

OBJECTIVE: To determine which chains of inter-alpha-inhibitor (I alpha I) are present in urine and whether they are also found in calcium oxalate (CaOx) crystals generated in human urine. MATERIALS AND METHODS: Fresh urine specimens were collected from five women and five men with no previous history of stone disease. An aliquot of each urine was retained for analysis, the remainder treated with a standard load of oxalate and the CaOx crystals precipitated from each specimen demineralized with ethylenediamine tetracetic acid. The resulting organic extracts from crystals and their corresponding urine samples were subjected to sodium dodecyl sulphate gel electrophoresis analysis and Western blotting using a commercial polyclonal antibody to I alpha I. RESULTS: Heavy chain 1 (H1) and 2 (H2) of I alpha I were commonly found in every urine sample, and in the CaOx crystals precipitated from those urine samples. Several protein bands were visible in urine samples from both sexes in the molecular mass range 25-70 kDa, which may be bikunin or its fragments. As well as H1 and H2, the crystals from both sexes contained a protein band at approximately 33 kDa. In many cases there appeared to be no direct relationship between the proteins detected in the crystals and the urine samples from which they were derived, which probably reflects the well known instability of I alpha I and the occurrence of a range of bikunin fragments in urine. CONCLUSION: These results show for the first time that H1 and H2 are present in human urine and urinary CaOx crystals, that the bikunin chain of I alpha I is not the only part of the molecule capable of participating in CaOx crystallization in urine, and in theory at least, in the regulation of crystallization events in stone formation. It is also apparent that significant fragmentation of I alpha I occurs both in vivo and in vitro, and this must be considered in any study attempting to elucidate the influence of this protein in the formation of CaOx stones.

Adult↗
PubMedDate not supplied

Enhanced solubility of 2,8 dihydroxyadenine (DOA) in human urine.

Water solubility of the adenine catabolite 2,8 dihydroxyadenine (DOA) frequently forms the basis for predicting potential DOA crystal formation in human urine following infusion of adenine-fortified blood. Measurements relevant to solubility, ionic dissociation, and supersaturability of DOA in aqueous buffers and human urine at 37 C establish striking quantitative differences in the physico-chemical behavior of DOA in the two media. The basal solubility of DOA is 1.53 +/- 0.04 mg/1 (approximately 9 X 10(-6) M) in water (pH 6.5). DOA is an ampholyte characterized by aqueous thermodynamic macrodissociation constants of pKa1 = 2.6, pKa2 = 8.1, and pKa3 = 11.52. This compound displays pH-dependent solubility, although significant solubility increases beyond basal values do not occur within the physiologic pH range for human urine. Supersaturated aqueous solutions (three to sixteen times basal solubility) can be achieved but are unstable. In contrast, human urine at 37 C exhibits enhanced capacity for solubilizing DOA. In vitro basal solubility is 2.68 +/- 0.84 mg/1 at pH 5.0 and 4.97 +/- 1.49 mg/1 at pH 7.8. The apparent pK 2for DOA in urine of 7.9 to 8.1 is dependent upon urine osmolality. Urine can be supersaturated with Doa in vitro to approximately ten times its basal solubility by adding DOA solubilized in weak base, or by evaporation of a urine-DOA mixture. DOA remains supersaturated in urine for at least 16 hours despite gentle agitation. Little variation in in vitro DOA apparent supersaturation was found among urine samples from four normal individuals (40.38 +/- 3.33 mg/1). A patient receiving oral adenine exhibited urinary DOA solubility in considerable excess (96.0 mg/1) of that predicted from water and from in vitro urine solubility studies. Thus, water solubility of DOA is poorly predictive of in vitro and in vivo DOA solubility in human urine. On the basis of these data, estimates of the load of adenine-fortified blood expected to result in urinary DOA crystal formation may be revised upward.

Adenine↗
PubMed1984

Urine glucose testing in the critically ill: a comparison of two enzymatic test strips.

The urine glucose concentration is commonly used to monitor indirectly the degree of hyperglycemia in critically ill patients and to adjust insulin dosage. Most commercially available urine glucose reagent test strips measure the urine glucose concentration from 0% to 2%. When the urine glucose is at the 2% level, the blood glucose concentration may vary over a wide range. We compared a new urine glucose test strip which measures the urine glucose concentration from 0% to 5% versus a conventional strip (0% to 2%) in the analysis of double-voided urine specimens from 285 patients with diabetes mellitus. Both types of test strips were insensitive in detecting hyperglycemia and showed a wide range of blood glucose values for each estimated urine glucose concentration. However, the new test strips which gave measurements at the 3% and 5% urine glucose concentrations allowed for more specificity (99%) in detecting blood glucose levels above 250 mg/dl. We conclude that: (a) test strips measuring from 0% to 5% are superior to conventional 0% to 2% test strips because the 3% and 5% urine glucose readings allow for a high level of specificity in detecting severe hyperglycemia (greater than 250 mg/dl); (b) urine glucose testing is insensitive and nonspecific in detecting hyperglycemia when urine glucose values are 2% or less.

Blood Glucose↗
PubMed2003

Analysis of topiramate and its metabolites in plasma and urine of healthy subjects and patients with epilepsy by use of a novel liquid chromatography-mass spectrometry assay.

A novel liquid chromatography-mass spectrometry (LC-MS) method was developed and validated for quantification of topiramate (TPM) and its metabolites 10-hydroxy topiramate (10-OH-TPM), 9-hydroxy topiramate (9-OH-TPM), and 4,5-O-desisopropylidene topiramate (4,5-diol-TPM) in plasma and urine. The method uses 0.5 mL of plasma or 1 mL of urine that is extracted with diethyl ether and analyzed by LC-MS. Positive ion mode detection enables tandem mass spectrometric (MS/MS) identification of the aforementioned four compounds. Calibration curves of TPM, 4,5-diol-TPM, 9-OH-TPM, and 10-OH-TPM in plasma and urine were prepared and validated over the concentration range of 0.625 to 40 microg/mL using TPM-d(12) as an internal standard. Calibration curves were linear over this concentration range for TPM and its metabolites. Accuracy and precision ranged in urine from 83% to 114% and 4% to 13% (%CV), respectively, and in plasma from 82% to 108% and 6% to 13%, respectively. The applicability of the assay was evaluated by analyzing plasma samples from a healthy subject who received a single oral dose of TPM (200 mg) and urine samples from 11 patients with epilepsy treated with TPM (daily dose between 100 to 600 mg) alone or with other antiepileptic drugs. Only TPM was detected and quantified in the plasma samples, and its concentration ranged between 0.7 and 4.3 microg/mL. The concentrations of TPM and 10-OH TPM were quantifiable in all urine samples and ranged from 20 to 300 microg/mL for TPM and from 1 to 50 microg/mL for 10-OH-TPM. The metabolites 4,5-diol-TPM and 9-OH-TPM were also detected in all urine samples, but their concentrations were quantifiable only in 4 patients. An unidentified peak in the chromatograms obtained from patients' urine was attributed to 2,3-O-desisopropylidene topiramate (2,3-diol-TPM). Due to a lack of reference material of 2,3-diol TPM and the similar MS/MS spectrum with 4,5-diol-TPM, the calibration curves of 4,5-diol-TPM were used for the quantification of its isomer 2,3-diol-TPM. Based on these determinations, the apparent 2,3-diol-TPM-to-TPM concentration ratio in patients' urine ranged from 0.05 to 0.51 and the 10-OH-TPM-to-TPM ratio ranged from 0.02 to 0.17. In conclusion, a novel LC-MS method for the assay of TPM and four of its metabolites in plasma and urine was developed. Its utilization for analysis of urine samples from patients with epilepsy showed that the method was suitable for analysis of TPM and its metabolites in clinical samples. Two quantitatively significant TPM metabolites (10-OH-TPM and 2,3-diol-TPM) and two quantitatively minor metabolites (9-OH-TPM and 4,5-diol-TPM) were detected and quantified in urine samples from patients with epilepsy.

Adult↗
PubMed1996

Detection of antibodies to Shigella lipopolysaccharide in urine after natural Shigella infection or vaccination.

The purpose of the present study was to explore the possibility of detecting antibodies to Shigella sonnei lipopolysaccharide (LPS) in urine after infection or vaccination. Urinary immunoglobulin A (IgA) and IgG antibodies and specific IgA secretory protein against S. sonnei LPS were measured by enzyme-linked immunosorbent assay (ELISA), after adjustment for urine concentration. A significant antibody level was defined as one above a cutoff value calculated from the geometric mean + 2 standard deviations of urinary anti-S. sonnei LPS levels in 43 healthy hepatitis B vaccinees (controls). Of 11 culture-proven cases of S. sonnei shigellosis, at convalescence 9 (82%) had significantly elevated levels of urinary antibodies to the homologous LPS. The S. sonnei conjugate vaccine, composed of S. sonnei O-specific polysaccharide covalently bound to recombinant exoprotein A of Pseudomonas aeruginosa, elicited a significant urine IgA or IgG anti-LPS response in 60% (6 of 10), 56% (9 of 16) 43% (16 of 37), and 14% (3 of 21) of the volunteers at 2 weeks, 6 weeks, 6 months, and 12 months after vaccination, respectively. The specificity of the urine antibody response to S. sonnei LPS was documented by the total lack of response in subjects who received parenteral Shigella flexneri 2a-recombinant exoprotein A conjugate (69 urine samples) or meningoccal tetravalent control vaccines (4 urine samples). All the volunteers who lacked a significant response to S. sonnei LPS in serum also lacked such response in urine samples. Seventy-four percent of the volunteers with a significant IgA or IgG anti-LPS response in serum at convalescence or 14 days after vaccination showed a similar response in urine. The ratio of the titer of secretory protein bound to IgA anti-S. sonnei LPS in urine to that in serum was 303 times higher than the ratio of anti-S. sonnei LPS total IgA titer in urine to that in serum, indicating that the urine IgA is of secretory origin. These findings suggest the possible use of urinary Shigella LPS antibodies as markers of systemic and secretory immune responses after natural infection or vaccination. At this stage, because of its limited sensitivity, the detection by ELISA of Shigella LPS antibodies in urine cannot replace the same assay in serum as a definitive test in an individual with a negative result.

Antibodies, Bacterial↗
PubMed2001

Determination of beryllium and selenium in human urine and of selenium in human serum by graphite-furnace atomic absorption spectrophotometry.

For human urine beryllium (Be), each sample (500 microl) was diluted (1+1) with Nash reagent (containing 0.2% (v/v) acetylacetone and 2.0 M ammonium acetate buffer at pH 6.0) and then a 20-microl volume of Triton X-100 (0.4%, v/v) aqueous solution was added. An aliquot (10 microl) of the diluted urine mixture was introduced into a graphite cuvette and was atomized according to a temperature program. The method detection limit (MDL, 3sigma) for Be was 0.37 microg/l in the undiluted urine sample and the calibration graph was linear up to 65.0 microg/l. Calibration graphs were prepared by the standard addition method. Accuracies of 98.6-102% were obtained when testing standard reference material (SRM 2670) freeze dried human urine samples. Precision (relative standard deviation, RSD) for urine Be was < or = 2.3% (withinrun, n = 5) and was < or = 3.0% (between-run, n = 3). For human urine and serum selenium (Se), samples (100 microl) were diluted with HNO3 (0.2%, v/v) to make a (1+1) dilution for urine analysis or a (1+4) dilution for serum analysis. An additional aliquot (10 microl) of Triton X-100 (0.1%, v/v) was added to each 200 microl of (1+1) diluted urine (or 20 microl of the Triton X-100 was added to each 500 microl of (1+4) diluted serum) sample. After the diluted sample mixture (10 microl) was introduced into a graphite cuvette, the corresponding chemical modifier (10 microl, containing Ni2+ + Pd + NH4NO3 in HNO3 (0.2%, v/v)) was added to it and the mixture was atomized. The MDL (3sigma) for Se in urine and in serum was 4.4 and 21.4 microg/l in undiluted sample, respectively, and the calibration graphs were linear up to 150 and 400 microg/l. Accuracies of urine Se were 98.9 - 99.4% by testing SRM 2670 (NIST) urine standards with RSD (between-run, n = 3) within 2.9%; and that of serum Se was 97.2% when testing a certified second-generation human serum (No. 29, #664) with RSD (between-run, n = 3) of 1.4%. The proposed method can be applied easily, directly, and accurately to the measurement of Be and Se in real samples (including six urine Se and four serum Se from patients of Blackfoot Disease in Taiwan).

Beryllium↗
PubMed1999

Effect of magnesium-deficient diet on serum and urine magnesium concentrations in healthy cats.

OBJECTIVE: To evaluate the efficacy of using serum total and ionized magnesium (Mg) concentrations and urine Mg concentrations to identify Mg deficiency in cats. ANIMALS: 6 healthy castrated male cats. PROCEDURE: A Mg-replete diet was fed for 37 days, followed by a Mg-deficient diet for 37 days. On days 1, 3, and 7 of the last week of each diet, serum ionized and total Mg concentrations were determined; in addition, urine Mg concentration was determined each day of the last week. Serum total and ionized Mg concentrations were compared with urine Mg concentration, amount of Mg excreted during 24 hours (24-hour urine Mg excretion), ratio of urine Mg concentration to urine creatinine concentration (Umg:Ucr), and urinary fractional excretion of Mg (FEmg) to determine which variable best predicted Mg status. RESULTS: Cats fed Mg-deficient diets had significantly lower serum total and ionized Mg concentrations and 24-hour urine Mg excretion values, compared with cats fed Mg-replete diets. Serum total Mg concentration was the best predictor of Mg status. Twenty-four-hour urine Mg excretion was a repeatable, reliable measurement and had the best correlation with serum total Mg concentration. Serum total Mg concentration also correlated with urine Mg concentration, Umg:Ucr, and FEmg. CONCLUSIONS AND CLINICAL RELEVANCE: Serum total and ionized Mg concentrations can be used to identify cats with dietary-induced Mg deficiencies. Twenty-four-hour urine Mg excretion and urine Mg concentration correlated best with serum total Mg concentration and, therefore, may be the most useful urine variables for identifying Mg deficiency.

Animal Feed↗
PubMed1984

"Pink urine" in morbidly obese patients following gastric partitioning.

A pink coating on the inner surface of plastic urinary tubing, which gave the impression that the urine was pink, had frequently been noted 4 to 24 hours following gastric partitioning by means of a stapler in morbidly obese patients. A study was therefore done in 187 such patients as well as in 14 patients of normal weight who had undergone abdominal surgery of comparable magnitude. Postoperatively "pink urine" was observed in 32% of the obese patients but in none of the nonobese patients; however, a pink sediment remained following centrifugation of urine collected postoperatively from all the obese patients. Microscopy of this sediment showed crystals of uric acid dihydrate; these were infrequent in the preoperative specimens but present in high concentration in the postoperative specimens, particularly those of "pink urine". X-ray diffraction analysis confirmed the nature of the crystals. Preoperatively the obese patients had high-normal serum levels of uric acid. Postoperatively in all the groups of patients the serum levels of uric acid decreased while the urine levels and the urinary clearance of uric acid increased; the last two values, however, were significantly greater, both preoperatively and postoperatively, in those who were morbidly obese. Compared with the patients who did not have "pink urine" the patients with "pink urine" were significantly more obese and had a significantly lower postoperative urine pH. The latter also had a marked postoperative increase in urine osmolality and were the only patients to have a significant postoperative decrease in urine output. Thus, the pink colour of this group's urine was attributed to precipitation of uric acid crystals, fostered by a decrease in pH and an increase in concentration of the urine.

Adult↗
PubMed1995

Transition zone index as a method of assessing benign prostatic hyperplasia: correlation with symptoms, urine flow and detrusor pressure.

PURPOSE: Prostate volume has been poorly correlated to various parameters used to assess benign prostatic hyperplasia (BPH), including symptoms, peak urine flow and detrusor pressure at peak urine flow. The purpose of this study was 2-fold: 1) to determine if transrectal ultrasound measurement of the transition zone of the prostate served as a better proxy for determining prostate size and correlated better with American Urological Association symptom score, peak urine flow and detrusor pressure, and 2) if the parameter transition zone index (the ratio between transition zone volume and prostate volume) was useful in evaluating clinical prostatism. MATERIALS AND METHODS: We prospectively evaluated 61 men with symptomatic BPH (age 64.6 +/- 9.7 years) according to symptoms, peak urine flow, pressure/flow analysis, transrectal ultrasound volume of the entire prostate and the transition zone, and calculation of the transition zone index. RESULTS: Age correlated with symptoms (r = 0.31, p = 0.01) and peak urine flow correlated negatively with symptoms and age (p = 0.002). Age also correlated with prostate volume (r = 0.54 and p = 0.03) and transition zone (r = 0.31, p = 0.05). There was a weak correlation between prostate volume and symptoms, peak urine flow and detrusor pressure at peak urine flow; a stronger correlation between transition zone and symptoms (r = 0.48, p = 0.03), and peak urine flow (r = -0.34, p = 0.05), and a significant correlation (p = 0.001) between transition zone index and symptoms (r = 0.75), peak urine flow (r = -0.71) and detrusor pressure at peak urine flow (r = 0.43). A transition zone index of greater than 0.50 was a useful cutoff point and highly significant (p = 0.002) for delineating patients with more severe abnormalities of symptoms, peak urine flow and detrusor pressure at peak urine flow. CONCLUSIONS: Transition zone index is a parameter that correlates significantly with evaluated parameters of BPH and may serve as a useful proxy for evaluating worsening obstruction. Studies are underway to determine if transition zone index can be used prospectively to predict and correlate response with therapies designed to ablate prostatic tissue medically or surgically.

Age Distribution↗
PubMed1997

Comparison of urine dipsticks with quantitative methods for microalbuminuria.

We describe a new dip- and read dipstick that detects urine albumin at concentrations of 10 mg/l and above and urine creatinine at concentrations of 300 mg/l and above. The albumin assay is based on a high-affinity, dye-binding technique while the creatinine assay is based on the peroxidase-like activity of copper creatinine complexes. With these two-test dipsticks, urines from normal adults supplemented with albumin and creatinine were correctly identified to within +/- 15% of the expected value for both analytes; the between-day coefficients of variation ranged from 7.1% to 16.1%. We tested 275 patients' unmodified urines by the Bayer and Boehringer Mannheim Micral-Test albumin dipsticks and for albumin with the Beckman Array on the same specimens. We also analyzed 42 selected urines from the group of 275 for albumin by another quantitative immunochemical method and by electrophoresis plus a total protein method to estimate the albumin concentration. The quantitative immunochemical methods appear to underestimate the urine albumin concentrations; in these 42 urines measured as negative, i.e., < ca. 16-20 mg/l, by one of the quantitative method but positive by the Bayer dipstick, 33 of these were positive by the electrophoresis/total protein assay combination. The Bayer albumin dipstick correctly identified urines as having < 16 mg/l or > or = 16 mg/l at an 80% rate. At a cutoff of 20 mg/l, the rate increased to 87%. We also determined the urinary albumin/creatinine ratios on the 275 patients using the Bayer two-pad dipstick and found agreement 84% of the time with the same ratio obtained from a quantitative immunochemical method for albumin and a rate-Jaffe method for creatinine; an albumin/creatinine ratio (mg/g) of 30 was used as the discrimination point. Albumin stability studies performed on the Beckman Array patients with six fresh urines showed small but consistent decreases at -20 degrees C but not at 4 degrees C after one month of storage. The albumin in contrived urines, as estimated by electrophoreses/total protein and by the dipsticks did not change at these storage conditions. Boric acid at 1 g/l as a urine preservative had no effect on the measurement of albumin by any of the methods described here nor of the assay of creatinine. Other urinary proteins present at abnormal excretion rates did not interfere with the Bayer albumin dipstick. Abnormal concentrations of bilirubin, citrate, creatine, ascorbic acid, albumin, hemoglobin and myoglobin in urine did not interfere with the creatinine dipstick measurements. The first four of the above did not affect the Bayer dipstick results for albumin.

Adult↗
PubMed2005

Ontogeny of urine preference and its relationship to NH4Cl preference and sodium hunger in suckling rat pups.

We chart the postnatal ontogeny of urine preference in the suckling rat. Twelve-day-old sucklings, when offered urine, NH4Cl, or NaCl, ingest more urine and NH4Cl than NaCl. When rendered sodium hungry by ivc renin or by sodium depletion, these sucklings prefer urine and NH4Cl to NaCl, dilute urine, or an NaCl and KCl mineral mix equimolar to urine; however, by 18 days of age, urine and NH4Cl are no longer preferred to NaCl. Hence, urine preference in the suckling may be specific and preparatory for the variety of purposes urine preference serves in the adult rat, and it might guide the pup to urinary sodium in the nest. Since preference for urine and NH4Cl covary during postnatal development, the high preference for NH4Cl in midterm sucklings might be because its ammonium flavor is similar to urine.

Ammonium Chloride↗
PubMed1985

Direct detection of the human papovavirus BK in urine of bone marrow transplant recipients: comparison of DNA hybridization with ELISA.

Urine specimens from bone marrow transplant (BMT) recipients and from controls were directly tested for BK virus (BKV) DNA sequences by dot hybridization and for BKV antigen by a double-antibody indirect ELISA. A total of 158 specimens from 55 BMT patients (57 collected prior to or at the time of transplantation and 101 in the posttransplant period) and single urines from 125 control subjects were examined by both methods. A molecularly cloned, 32P-labelled BKV probe was hybridized with urine sediments that were spotted directly on nitrocellulose filters and denatured in situ. BKV DNA sequences were detected in 1 (1.8%) pretransplant and 22 (21.8%) posttransplant urines of BMT patients, and in none of control urines. In ELISA of urine supernatants, BKV antigen was detected in 1 (1.8%) pretransplant and 21 (20.8%) posttransplant urines of BMT patients and in 1 (0.8%) of the control urines. The results of the two tests correlated as follows: 16 urines were positive and 253 urines negative by both methods; seven specimens were positive by DNA hybridization only and seven were positive by ELISA alone. Virus excretion in urine was demonstrated in 20 (36.4%) patients by DNA hybridization, in 19 (34.5%) patients by ELISA, in 15 (27.3%) patients by both methods, and in 24 (44%) patients by at least one of the two tests.

Adolescent↗
PubMed2006

Does the composition of voided urine reflect that of the renal pelvis?

Studies have shown that the urothelium has a transport function and that urine composition changes on its way through the urinary tract. In this study, we investigated the hypothesis that the composition of voided urine differs from and does not reflect that of the renal pelvis. Urine samples were obtained from the renal pelvis and voided urine of 18 healthy volunteers (mean age 36.2+/-5.1 SD years, 10 men, 8 women). The pH was determined using a pH electrode, osmolality by means of micro-osmometry and Na and K using flame photometry. In comparison to the urine of the renal pelvis, voided urine showed significant increases in pH, osmolality and Na and K concentrations (P<0.05 for each). There were no significant differences in gender and age. This study has demonstrated that the pH, osmolality, Na and K of voided urine differ significantly from the values in the renal pelvis. Urine composition is thus modified as it passes through the urinary tract, which would support the concept of a dynamic urothelium. The composition of voided urine does not seem to compare to renal pelvic urine. This concept needs to be considered in urine analysis evaluation and its relation to renal function.

Adult↗
PubMed1999

Biological monitoring of workers exposed to 4,4'-methylene-bis-(2-orthochloroaniline) (MOCA). I. A new and easy determination of "free" and "total" MOCA in urine.

OBJECTIVE: The objective of the study was to validate a new and simple method to determine MOCA in the urine of exposed workers. METHODS: The separation, identification and quantification of urinary MOCA were performed in spiked urines by a sensitive and practical high-performance liquid chromatography (HPLC) method and applied to urine samples of 11 workers occupationally exposed to MOCA; the postshift urinary levels of MOCA in their urine samples with and without hydrolysis, "total" and "free" MOCA respectively, were determined. In addition, we investigated the use of citric or sulfamic acid as preservatives of urine samples. RESULTS: The "total" and "free" MOCA were extracted with isooctane from hydrolysed and nonhydrolysed 20-ml urine samples respectively. After evaporation, the residue was dissolved in 4 ml of 2.10(-2) M aqueous hydrochloric acid and analysed by an isocratic HPLC system using both ultraviolet (UV) detection at 244 nm and electrochemical detection working in oxidation mode (0.9 V) with an Ag/AgCl reference electrode. Mobile phase (50% acetonitrile in water containing 0.4% acetate buffer solution pH = 4.6) was used to complete the 20-min analysis. "Free" and "total" MOCA were chromatographed on a reversed-phase C8 column (5 microns, 250 mm x 4 mm). The standard curve of MOCA was linear over the range 5-500 micrograms/l in human urine. The detection limit was 1 microgram/l for a 20-microliter injection volume; the repeatability ranged from 5.6 to 1.3% (n = 6) for spiked urines at 5 and 500 micrograms/l, with a percentage recovery of 94 +/- 3%. The reproducibility of the method was 7.3% (n = 4) for spiked urine at 10 micrograms/l. The use of sulfamic acid as a preservative of urine samples is important to improve the precision and accuracy of the analysis. CONCLUSION: The results indicate that these analytical procedures using conventional apparatus may be used routinely and reliably with large numbers of urine samples for biological monitoring of the exposure to MOCA. The occupational exposure to MOCA in some factories in France is studied in the second part of this work.

Carcinogens↗