Isolated Urine Sample Research Articles

A 38-year-Old Woman With Flaccid Tetraparesis after Presenting With Abdominal Pain

A 38-year-old woman presented in the emergency department with acute abdominal pain. She underwent laparoscopic cholecystectomy. Postoperatively, she developed worsening abdominal pain, tachycardia, flaccid tetraparesis, urinary retention, constipation and SIADH. She also developed red-colored urine. Porphobilinogen was requested in an isolated urine sample, with the test result showing 256 mg/g of creatinine. This case didactically emphasizes the necessity of considering differential diagnosis in acute abdomen pain associated with neurological disorders.

Kidney subclinical lesions in hypertension phenotypes defined by Home Blood Pressure Monitoring among young adults enrolled in a Family Health Strategy unit

Abstract Introduction The association between kidney lesion, hypertension (HTN) and cardiovascular risk (CV) is well established. Asymptomatic patients with decreased glomerular filtration rate (GFR) and/or increased albuminuria seem to have increased CV risk. The refinement of HTN diagnosis using Home Blood Pressure Monitoring (HBPM) allows to identify individuals with different phenotypes: normotension, sustained HTN (SHT), masked HTN (MHT) and white-coat HTN (WHT), increasing diagnostic accuracy. Objective To assess kidney subclinical lesions among different hypertension (HTN) phenotypes identified by Home Blood Pressure Monitoring (HBPM) in an adult population enrolled in a Family Health Strategy unit. Design and Methods: Cross-sectional, populational study with adults between 20-50 years old enrolled in a Family Health Strategy unit in a metropolis. Sociodemographic, anthropometric and CV risk factors were registered. Office blood pressure (BP) was the average of two consecutive measurements, and HBPM followed a 7-day protocol. HBPM < 135x85 mmHg and office BP < 140x90mmHg were considered normal, identifying four phenotypes: normotension (controlled office BP and HBPM); white-coat hypertension (uncontrolled office BP and controlled HBPM); masked hypertension (controlled office BP and uncontrolled HBPM) and sustained hypertension (uncontrolled office BP and HBPM). Albuminuria was dosed in an isolated urine sample whereas glomerular filtration rate was calculated by CKD Epi formula using serum creatinine. Results A total of 483 individuals were evaluated (39% male; mean age: 37.6 ± 8.8 years). More often, individuals with white-coat hypertension (9.3%) are male, with greater neck circumference and higher prevalence of metabolic syndrome. Individuals with masked hypertension (10%) are more obese, with increased neck and waist circumferences whereas those who present sustained hypertension are predominantly male, more obese, with increased neck and waist circumferences and higher prevalence of diabetes and metabolic syndrome. Analyzing four phenotypes, a progressive albuminuria increase was observed among normotensive patients: white-coat hypertension 4.0 ± 2.2; masked hypertension 5.3 ± 3.4 and sustained hypertension 7.1 ± 1.4 mg/g creatinine. We also observed an increased serum creatinine and decreased GFR: white-coat hypertension 0.74 ± 0.16/132 ± 34; masked hypertension 0.79 ± 0.17/123 ± 28; sustained hypertension 0.81 ± 0.32/120 ± 59, respectively, although without statistical significance. Conclusion The performance of HBPM refined HTN diagnosis and was able to early identify a progressive worsening of kidney function parameters in the different phenotypes.

KIDNEY SUBCLINICAL LESIONS IN HYPERTENSION PHENOTYPES DEFINED BY HOME BLOOD PRESSURE MONITORING AMONG YOUNG ADULTS ENROLLED IN A FAMILY HEALTH STRATEGY UNIT

Objective: To assess kidney subclinical lesions among different hypertension (HTN) phenotypes identified by Home Blood Pressure Monitoring (HBPM) in an adult population enrolled in a Family Health Strategy unit Design and method: Cross-sectional, populational study with adults between 20–50 years old enrolled in a Family Health Strategy unit in a metropolis. Sociodemographic, anthropometric and CV risk factors were registered. Office blood pressure (BP) was the average of two consecutive measurements, and HBPM followed a 7-day protocol. HBPM < 135x85 mmHg and office BP < 140x90mmHg were considered normal, identifying four phenotypes: normotension (controlled office BP and HBPM); white-coat hypertension (uncontrolled office BP and controlled HBPM); masked hypertension (controlled office BP and uncontrolled HBPM) and sustained hypertension (uncontrolled office BP and HBPM). Albuminuria was dosed in an isolated urine sample whereas glomerular filtration rate was calculated by CKD Epi formula using serum creatinine. Results: A total of 483 individuals were evaluated (39% male; mean age: 37.6 ± 8.8 years). More often, individuals with white-coat hypertension (9.3%) are male, with greater neck circumference and higher prevalence of metabolic syndrome. Individuals with masked hypertension (10%) are more obese, with increased neck and waist circumferences whereas those who present sustained hypertension are predominantly male, more obese, with increased neck and waist circumferences and higher prevalence of diabetes and metabolic syndrome. Analyzing four phenotypes, a progressive albuminuria increase was observed among normotensive patients: white-coat hypertension 4.0 ± 2.2; masked hypertension 5.3 ± 3.4 and sustained hypertension 7.1 ± 1.4 mg/g creatinine. We also observed an increased serum creatinine and decreased GFR: white-coat hypertension 0.74 ± 0.16/132 ± 34; masked hypertension 0.79 ± 0.17/123 ± 28; sustained hypertension 0.81 ± 0.32/120 ± 59, respectively, although without statistical significance. Conclusions: The performance of HBPM refined HTN diagnosis and was able to early identify a progressive worsening of kidney function parameters in the different phenotypes.

Antimicrobial activity of <i>Moringa oleifera</i> leaf extracts on multiple drug resistant bacterial isolates from urine samples in Benin City

The aim of this study was to examine the antibacterial effect of Moringa oleifera leaf extracts on selected multiple drug resistant (MDR) bacterial isolates. Escherichia coli , Pseudomonas aeruginosa and Staphylococcus aureus were isolated urine samples from patients attending Lahor Research Medical Centre. Multiple drug resistant bacteria were generated from the isolates by carrying out antibiotic susceptibility testing using the Kirby-Bauer disc diffusion technique. Three isolates each from the multidrug resistant bacteria were selected and molecular characterization was performed for confirming microbial identity. The antibacterial activity of methanol, chloroform and aqueous leaf extracts of M. oleifera at different concentrations (6.25, 12.5, 25, 50 and 100 mg/ml) were analyzed on the selected MDR bacteria using agar disc diffusion method. M. oleifera leaf extracts were observed to inhibit the growth of multidrug resistant bacteria. The highest antibacterial activity 9.32±1.45 mm was observed with the chloroform extracts, while the lowest value of 0.27±0.27 mm was obtained for the aqueous leaf extract. The antibacterial activity examined in this study showed that chloroform and methanol M. oleifera leaf extracts are capable of exerting inhibitory effect on multidrug resistant bacteria. The results obtained in this study indicated that M. oleifera can be a potential source for the treatment of different infections caused by multiple drug resistant bacteria. Keywords: Urine, Multidrug resistant bacteria, polymerase chain reaction, Moringa oleifera , antimicrobial

Albuminuria and glomerular filtration rate in obese children and adolescents.

Objective:To describe the frequency of albuminuria in overweight and obese children and adolescents and to relate it to the severity of obesity, pubertal staging, associated morbidities and the glomerular filtration rate.Method:Cross-sectional study including 64 overweight and obese children and adolescents between 5 and 19 years of age.Data collected:weight, height, waist circumference and systemic arterial pressure.Laboratory tests:lipid profile; glycemia and insulin, used to calculate the Homeostasis Model Assessment (HOMA-IR); C-reactive protein; glutamic-pyruvic transaminase and albuminuria in an isolated urine sample (cutoff <30 mg/g). Creatinine was used to calculate the estimated glomerular filtration rate (eGFR, mL/min/1.73 m2).Results:The mean age was 11.6 ± 3.4 years, 32 (50%) and 29 (45.3%) were male and prepubertal. Forty-six (71.9%) had severe obesity. The frequency and median (min/max) of the observed values for albuminuria (> 30 mg/g) were 14 (21.9%) and 9.4 mg/g (0.70, -300.7 mg/g). The mean eGFR was 122.9 ± 24.7 mL/min/1.73 m2. There was no significant correlation between body mass index, pubertal staging, insulin and HOMA-IR with albuminuria values and neither with eGFR. Children with albuminuria tended to have higher values of diastolic blood pressure (75.0 ± 12.2 vs. 68.1 ± 12.4, p = 0.071).Conclusion:Albuminuria, although frequent in children and adolescents with obesity, was not associated with other morbidities and the glomerular filtration rate in these patients.

Sodium excretion and associated factors in urine samples of African descendants in Alcântara, Brazil: a population based study

In most countries, salt intake has been excessive and constitutes one of the main risk factors for disease development, especially hypertension. Factors such as age, gender, sedentary lifestyle, smoking, African descent, obesity, dietary habits and family history of hypertension may be associated with high blood pressure. Studies show a positive association between the excretion of sodium and increased blood pressure. We evaluated the urinary excretion of sodium and associated factors in isolated urine samples of African descendants from remaining Quilombos. We performed a cross-sectional, population-based study with 1162 African descendants living in remaining quilombos in Alcântara, Maranhão, Brazil. Demographic, nutritional, clinical and laboratory data were analyzed. Urinary sodium excretion was estimated using the Kawasaki equation. A multivariate linear regression model was used to identify the variables related to sodium excretion. The average age was 37.6 ± 11.8 years and 51.2% were women. The prevalence of hypertension was 21.3%. The average urinary excretion of sodium was high, especially among the hypertensive (217.9 ± 90.1 vs. 199.2 ± 83.0 mmol/d; p = .002). After an adjusted analysis, only the waist circumference (odds ratios (OR) = 1.16; confidence intervals(CI)95%: 1.03–1.30), triglyceride (OR = 1.13; CI95%: 1.05–1.22), systolic blood pressure (OR = 1.19; CI95%: 1.08–1.32) and Chronic Kidney Disease Epidemiology (CKD-EPI;OR = 1.24; CI95%: 1.15–1.35) remained related to urinary sodium excretion. African descendants had a high rate of sodium excretion, especially among those who had hypertension. Abdominal adiposity, triglyceride and systolic blood pressure levels and renal function by CKD-EPI equation were associated to urinary sodium excretion.

Formula to detect high sodium excretion from spot urine in chronic kidney disease patients.

Excessive sodium intake is related to adverse renal and cardiovascular outcomes in patients with chronic kidney disease (CKD) and assessment of sodium intake is complex and not evaluated very often in clinical practice. To develop a new formula to estimate 24h sodium excretion from urine sample (second void) of patients with CKD. We included 51 participants with CKD who provided 24-hour urine collection and a sample of the second urine of the day to determine the sodium excretion. A formula to estimate the 24-hour sodium excretion was developed from a multivariate regression equation coefficients. The accuracy of the formula was tested by calculating the P30 (proportion of estimates within 30% of measured sodium exection) and the ability of the formula to discriminate sodium intake higher than 3.6 g/day was evaluated by ROC curve. Correlation test between measured and estimated sodium was significant (r = 0.57; p < 0.001), but P30 test identified a low accuracy (61%) of the formula. Different cutoff points were tested by performance tests and a ROC curve was generated with the cutoff that showed better performance (3.6 g/day). An area under the curve of 0.69 with a sensitivity of 0.91 and specificity of 0.53 was obtained. A simple formula with high sensitivity in detecting patients with sodium consumption higher than 3.6 g/day from isolated urine sample was developed. Studies with a higher number of participants and with different populations are necessary to test formula´s validity.

Microvascular Outcomes after Metabolic Surgery (MOMS) in patients with type 2 diabetes mellitus and class I obesity: rationale and design for a randomised controlled trial

IntroductionThere are several randomised controlled trials (RCTs) that have already shown that metabolic/bariatric surgery achieves short-term and long-term glycaemic control while there are no level 1A of evidence data regarding...

Management of chronic kidney disease- an update

Chronic kidney disease (CKD) is a global public health issue demanding continuous improvement in its management. Different international groups and organizations have now achieved a good progress in its definition, classification (staging), treatment and referral criteria to nephrologists. In definition of CKD, "CKD is defined as abnormalities of kidney structure or function, present for at least three months with implications for health", the phrase "with implications for health" has been added at the end of the previous definition, which reflects the concept that there may be certain abnormalities of kidney structure or function that do not have prognostic consequences (for example, a simple renal cyst). At staging of CKD, grade 3 has been subdivided into G3a and G3b, according to whether the glomerular filtration rate (GFR) is (59 - 45) or (44 - 30) ml/min/1.73m2, respectively. Furthermore, albuminuria has been classified in any GFR grade, in to A1, A2 or A3 according to the albumin-creatinine ratio (ACR) in an isolated urine sample for values &lt;3, 3-30 or &gt;30mg/mmol, respectively. The term "microalbuminuria" has now been replaced by the term "moderately increased albuminuria". For GFR measurement Chronic Kidney Disease Epidemiology Collaboration (CKD- EPI) equation has been preferred than the Modification of Diet in Renal Disease (MDRD) study equation and new 2012 KDIGO guidelines consider the use of alternative formulas to be acceptable if they have been shown to improve accuracy when compared with the CKD-EPI formula. For detection of albuminuria ACR is preferred rather than conventional 24 hours urine albumin. The recommended BP control target is ?140/90mmHg (both diabetic and non-diabetic) if ACR &lt;3mg/mmol and a stricter target is suggested, with BP ?130/80mmHg, (both in diabetic and non-diabetic) if the ACR is ? 3mg/mmol. Use of erythropoisis-stimulating agent (ESA) in anemia of CKD should be rational; to avoid its adverse effects like stroke, thrombosis or hypertension acceleration and hemoglobin goals should not exceed 11 g per dl. Treating dyslipidaemia in CKD with statins for all adults &gt;50 years of age, irrespective of low density lipoprotien (LDL) cholesterol levels is recommended. Referral to nephrologist should be rational according to guidelines and at least one year prior to the start of renal replacement therapy (RRT).Faridpur Med. Coll. J. 2014;9(1): 46-52

Assessment of dietary intake and urinary excretion of sodium and potassium in adults

Hypertension is associated with elevated sodium and low potassium intakes. The determination of sodium and potassium intake by dietary records is inaccurate, being its measurement from 24-h urine collection the reference method. To determine urinary sodium and potassium excretion in adults. To compare dietary sodium and potassium intake and their excretion from an isolated urine sample against the reference method. Seventy healthy adults aged 35 ± 8 years with a body mass index 25 ± 2 kg/m² (36 women) were studied. Urine was collected over 24 h, including an isolated urine sample taken in fasting conditions. Additionally, three 24-h dietary records were performed. Reported sodium and potassium intake was 2,720 ± 567 and 1,068 ± 433 mg/day, respectively. In turn, urinary excretion of sodium and potassium was 4,770 ± 1,532 and 1,852 ± 559 mg/day, respectively. These latter values were significantly higher than those obtained by dietary records. Furthermore, the urinary sodium and potassium excretion estimated from an isolated urine sample was 4,839 ± 1,355 and 1,845 ± 494 mg/day, respectively. These values were similar to those obtained with a 24 h urine collection. Dietary records underestimated electrolyte intake when compared with the reference method. Using an isolated urine sample to estimate electrolyte intake may be a reliable alternative.

Diagnostic Accuracy of Urine Dipsticks for Detection of Albuminuria in the General Community

Urine dipsticks, an inexpensive accessible test for proteinuria, are widely advocated for mass screening; however, their diagnostic accuracy in the general community is largely unknown. Evaluation of diagnostic test accuracy in a cross-sectional cohort. AusDiab, a representative survey of Australian adults 25 years and older (conducted in 1999/2000). Stratified cluster random sampling from 11,247 individuals participating in the biomedical examination; complete urinalysis data available for 10,944. Urine dipsticks (Bayer Multistix), with a positive result defined as ≥1+ or trace or higher protein. Albumin-creatinine ratio (ACR), measured on a random spot urine sample. Reference test positivity was defined as ACR ≥30 mg/g or ACR ≥300 mg/g. Numbers of participants with ACR <30, 30-300, and ≥300 mg/g were 10,219 (93.4%), 634 (5.8%), and 91 (0.8%), respectively. The area under the receiver operating characteristic curve (AUC) for dipstick detection of ACR ≥30 mg/g was 0.8451 ± 0.0129 (SE) in men and 0.7775 ± 0.0131 in women (P < 0.001). The AUROC for dipstick detection of ACR ≥300 mg/g was 0.9904 ± 0.0030 in men and 0.9950 ± 0.0016 in women (P = 0.02). Dipstick result ≥1+ identified ACR ≥30 mg/g with 57.8% sensitivity (95% CI, 54.1%-61.4%) and 95.4% specificity (95% CI, 95.0%-95.8%) and identified ACR ≥300 mg/g with 98.9% sensitivity (99% CI, 92.1%-100%) and 92.6% specificity (99% CI, 92.0%-93.3%). A dipstick result of trace or higher identified ACR ≥30 mg/g with 69.4% sensitivity (95% CI, 65.9%-72.7%) and 86.8% specificity (95% CI, 86.1%-87.4%) and identified ACR ≥300 mg/g with 100% sensitivity (99% CI, 94.3%-100%) and 83.7% specificity (99% CI, 82.8%-84.6%). A negative dipstick result (less than trace) had a negative predictive value of 97.6% (95% CI, 97.2%-97.9%) for ACR ≥30 mg/g and a negative predictive value of 100% (99% CI, 99.9%-100%) for ACR ≥300 mg/g. The probability of an ACR ≥30 mg/g confirmed on laboratory investigation was 47.2% (95% CI, 43.9%-50.5%) based on a dipstick result ≥1+ and 27.1% (95% CI, 25.1%-29.2%) based on a trace or higher result. Isolated urine samples precluded assessment of test reproducibility. Urine specific gravity and pH were not recorded; therefore, the effect of urine concentration on test performance was not assessed. A dipstick test result <1+ or less than trace has a high negative predictive value in the general community setting, with minimal risk of a missed diagnosis of macroalbuminuria. High false-positive rates emphasize the need for laboratory confirmation of positive results.

Enfermedad renal crónica: Clasificación, identificación, manejo y complicaciones

The key messages of these guidelines on chronic kidney disease are: Chronic kidney disease (CKD) is a public health problem due to its wide distribution, high rate of complications and cost. CKD is a common condition, its prevalence being about 10%, and is treatable if it is detected on time. A patient with CKD has a higher risk of cardiovascular mortality than of progression of its underlying renal disease. A new definition of CKD, based on estimated Glomerular Filtration Rate (eGFR) and kidney damage, facilitates its detection and management. CKD is detected with three simple tests: 1) Blood pressure measurement, 2) Detection of proteinuria or albuminuria in an isolated urine sample, and 3) Estimation of renal function (eGFR), based on serum creatinine, age, gender and race. The CKD risk groups are individuals with diabetes, hypertension and a family history of renal disease. The most cost-effective measures are to detect and treat diabetic and hypertensive patients in the community. Therapy must emphasize the maximal reduction of cardiovascular risk. The complications of CKD such as anemia and renal osteodystrophy can be identified and treated on time. Most patients with chronic kidney disease are detected in the community, therefore their initial care must be organized at the level of primary care, along with programs for hypertension and diabetes.

Iodine Nutrition in the Adult Population of Galicia (Spain)

To identify the current state of iodine nutrition in the adult population of Galicia (Spain), which is considered iodine sufficient based on results from studies carried out on schoolchildren. Urinary iodine concentration (UIC) and its relationship with different socio-demographic variables were assessed. A cross-sectional study was carried out on the population aged above 18 years in the Autonomous Community of Galicia (Spain) during 2004. The UICs were determined in an isolated urine sample using Dunn's colorimetric method. Iodine status was based on World Health Organization/International Council for the Control of Iodine Deficiency Disorders (WHO/ICCIDD) UIC. A total of 2877 urine samples were taken. Median UIC for the total Galician population was 75.6 microg/L. About 30% of the population showed a UIC below 50 microg/L. Educational level, place of residence (coast vs. inland), and consumption of iodized salt were independent variables associated with the iodine nutrition of the adult population of Galicia. There is "mild" iodine deficiency (WHO) in the adult population of Galicia, which affects all the groups analyzed and which is particularly significant in the group of women of a fertile age. The data obtained on the state of iodine nutrition in school-age populations cannot be extended to the adult population.

Human volunteer study on the influence of exposure duration and dilution of dermally applied N-methyl-2-pyrrolidone (NMP) on the urinary elimination of NMP metabolites

N-Methyl-2-pyrrolidone (NMP) is a versatile solvent used in various industrial processes and applications. Apart from its mildly irritating effects on the eyes, the mucous membranes and the skin, NMP has revealed prenatal toxicity in animal experiments after the oral administration of high doses. The dermal absorption of NMP and the urinary elimination of its main metabolites were investigated within an experimental exposure study. Four male volunteers were exposed to liquid NMP under occlusive conditions on the back of one hand with varying exposure times and solvent concentrations. Urine was collected before, during and after the exposure and analysed for the main NMP metabolites 5-hydroxy-N-methyl-2-pyrrolidone (5-HNMP) and 2-hydroxy-N-methylsuccinimide (2-HMSI). The urinary concentration of the metabolites upon exposure to undiluted NMP for 2 h increased rapidly with 5-HNMP reaching a maximum at 4-5 h and 2-HMSI after 26-29 h. The application of aqueous NMP solutions resulted in a delay of the peak time for 5-HNMP of approximately 6 h as compared with the undiluted solvent. An average dermal absorption of 5.4+/-1.5 mg NMP cm(-2) h(-1) was calculated for a 2 h exposure to undiluted NMP (6.5+/-2.0 mg NMP cm(-2) h(-1) for a 30 min exposure). Aqueous dilution of NMP to 50% was followed by a decrease of the absorption to 0.9+/-0.5 mg NMP cm(-2) h(-1). NMP metabolite concentrations in the range of the detection limits were found only in isolated urine samples after exposure to 10% NMP in aqueous dilution. NMP is rapidly absorbed across the skin and the dermal route may contribute significantly to the uptake of the solvent. Therefore, a biomonitoring of NMP exposed workers is essential for occupational-medical surveillance. Both urinary metabolites reflect the internal dose after a dermal absorption of NMP and thus qualify as suitable biomarkers for NMP exposure.

Evaluation of lithogenic elements in urine of healthy newborns

The determination of urinary excretion of lithogenic elements in healthy newborns involves factors ranging from urine collection and data handling to maternal influences, which can cause difficulties in analyzing the results. The objective of this study was to determine normal values of parameters related to lithogenesis, such as calcium, uric acid, citrate, and oxalate, in urine of healthy newborns using isolated samples, focusing on variations according to gender, weight, milk ingestion, and family history of lithiasis. Parameters measured in isolated urine samples from 104 healthy newborns (77 males and 27 females) were corrected by creatinine. The ratios were expressed as milligram/milligram of creatinine: calcium/creatinine of 0.10+/-0.01 (X+/-SE), uric acid/ creatinine of 1.10+/-0.10, citrate/creatinine of 0.56+/-0.04, and oxalate/creatinine of 0.07+/-0.01. Differences were observed between males and females, in terms of uric acid (0.80+/-0.07 vs. 1.10+/-0.10 mg/mg, P<0.05), citrate (0.05+/-0.06 vs. 0.17+/-0.05, P<0.05), sodium (0.17+/- 0.01 vs. 0.05+/-0.01, P<0.001), and potassium (0.05+/- 0.01 vs. 0.20+/-0.02, P<0.001). Interestingly, the urinary concentration of protector factors such citrate and potassium was higher in females than in males with low sodium excretion. Artificial milk feeding leads to higher calcium (0.10+/-0.06 vs. 0.06+/-0.01), uric acid (1.40+/-0.20 vs. 0.90+/-0.09, P<0.05), citrate (0.90+/-0.09 vs. 0.50+/-0.04, P<0.001), and oxalate (0.17+/-0.03 vs. 0.05+/-0.01, P<0.001) excretion when compared with breast feeding. There was higher excretion of calcium and sodium in patients under 3 kg. Children with familial antecedents presented some differences in urinary excretion, with higher uric acid (1.50+/-0.30 vs. 0.80+/-0.08, P<0.05) but lower calcium (0.05+/-0.02 vs. 0.10+/-0.01, P<0.05) and sodium (0.15+/-0.02 vs. 0.20+/-0.02, P<0.05) excretion, respectively. This report provides urinary parameters obtained in healthy newborns and correlates them with factors that could be involved in the genesis of osteopenia, renal stones, and/or nephrocalcinosis.

Retinol-binding protein urinary levels in a pediatric population: evolution according to age

OBJECTIVE: The kidney of the child, mainly the newborn, is specially susceptible to ischemic and/or toxic injuries, which can affect the renal tubular function. Therefore, reliable and precocious markers of tubular dysfunction would be useful in Pediatrics. The urinary levels of retinol binding-protein (RBPu) has been used in this way. Our goal was to evaluate the RBPu behavior in childhood to establish a reference interval and verify possible differences according to the age. METHODS: We studied healthy children aged 1 month to 8 years and healthy term and preterm babies; in the last group we only included babies without hemodynamic repercussion. We collected isolated urine samples once for children above 1 month and periodically for those below this age. In this urine, besides the dipsticks test (Combur 9(R), Boehringer), RBPu and creatinine were measured. RESULTS: We observed that the RBPu levels in childhood do not have a normal distribution; after logarithm data transformation we were able to establish an interval of reference for children above one month of age: 3 to 269 micro g/L, mean of 27 micro g/ L. In newborns, we found a large variation of RBPu excretion. However, we noticed that the excretion decreases significantly, reaching the healthy adult levels at the end of the 1st month, for term as well as for preterm newborns. CONCLUSIONS: We suggest that RBPu can be used as a marker of proximal tubular dysfunction, since we could establish an interval of reference, and it can be repeated whenever necessary in the follow-up of this kind of injury, because it is not an invasive exam. Moreover, this study contributes to the knowledge of the tubular function development for showing that at the end of the 1st month of life the newborn's kidney is able to reabsorb RBPu as the healthy adult kidney is.

The urinary excretion of cocaine and metabolites in humans: a kinetic analysis of published data.

Cocaine plasma levels and urinary excretion data from the literature were subjected to kinetic analysis. The objective was to present the available empirical data in a more useful form and provide a basis for interpretation of cocaine and/or metabolite concentrations in isolated urine samples. Cocaine disposition was modeled as a one-compartment open kinetic system exhibiting linearity within the usually encountered dose range. Model-predicted urine concentrations of cocaine, benzoylecgonine, and ecgonine methyl ester after a 100-mg cocaine dose were compared with literature values to test the validity of the model, and to indicate the use of ratios of concentrations in isolated urine samples to estimate the time since the dose of cocaine. A nomogram relating BZ urine concentrations to cocaine doses was constructed.