Newborn Urine Research Articles

Urine Derived Cells are a Potential Source for Urological Tissue Reconstruction

Contemporary approaches to tissue engineering and cell therapy for urinary tract reconstruction require invasive tissue biopsies to obtain autologous cells. However, these procedures are associated with potential complications. We determined whether the cells present in urine have characteristics of normal bladder cells and investigated their potential uses for urological reconstructive procedures. A total of 55 urine samples were collected from 15 healthy individuals and 8 patients with vesicoureteral reflux. Urine derived cells were isolated, expanded and tested for progenitor and differentiated cell specific markers using flow cytometry, immunofluorescence and Western immunoblotting. The chromosomal stability of cultured urine derived cells was determined by karyotype analysis. Clones were successfully established from primary cultures of urine derived cells. Isolated cells showed 3 phenotypes, including fully differentiated, differentiating and progenitor-like cells. Some urine derived cells stained positive for the surface markers c-Kit, SSEA4, CD105, CD73, CD91, CD133 and CD44. Two to 7 cells per 100 ml urine were multipoint progenitors that could expand extensively in culture. Single progenitor cells had the ability to differentiate into the cell lineages expressing urothelial, smooth muscle, endothelial and interstitial cell markers. The expression of lineage markers was characterized by Western blot and immunofluorescence analysis. Urine derived cells also maintained a normal karyotype after serial culture. A subpopulation of cells isolated from urine had progenitor cell features and the potential to differentiate into several bladder cell lineages. Urine derived cells could serve as an alternative cell source for urinary tract tissue engineering and reconstruction.

Urinary Reference Values for Stone Risk Factors in Children

Reference values for stone risk factors in 24-hour urine samples for nonstone forming children are limited. We measured urinary stone risk factors in healthy children 3 to 18 years old, and sought to determine whether the risk factors are affected by age. A total of 48 healthy subjects with no history of stone disease, endocrine abnormalities or urological surgery were recruited from the Naval Medical Center in San Diego. Subjects were then further divided into 4 age groups, each separated by 5 years. A single outpatient 24-hour urine sample was obtained and analyzed. Urine chemistries were adjusted for urinary creatinine and body weight. After excluding under collected samples 46 urine samples were analyzed. Urinary pH and volume decreased with increasing age, although the difference in pH did not reach statistical significance. Unadjusted urinary parameters failed to show statistical difference among the age groups. When adjusted for urinary creatinine and body weight all urinary parameters (calcium, oxalate, uric acid, citrate, magnesium, sodium, phosphorus and potassium) decreased with increasing age (statistically significant except for calcium). Stone risk factors in 24-hour urine samples decrease with increasing age in healthy, nonstone forming children. Normative data, derived by adjustment with urinary creatinine or body weight and stratified according to quintiles of age, should be useful in defining abnormal stone risk factors in children with stones.

Rubella outbreak on Tokunoshima Island in 2004: Serological and epidemiological analysis of pregnant women with rubella

This paper presents the serological and epidemiological background of the rubella-infected pregnant women following the rubella outbreak throughout Tokunoshima Island that occurred after the revision of the immunization law in Japan. Twelve of 149 pregnant women managed in Miyagami Hospital were enrolled as having a high risk for congenital rubella infection. They were interviewed about their immunization history with rubella vaccine, the presence of rash, onset of rash, and the presence and timing of contact with rubella-infected patients. The obstetric histories were investigated for past rubella HI antibody titer. Nine of 12 women continued their pregnancy and delivered a baby. A serological test for rubella IgM antibody and a reversed transcription-nested PCR assay using umbilical cord blood and the newborn urine for virus genome detection were performed for all babies. We also enrolled all 309 mothers who delivered during the last 2 years in Miyagami Hospital, and retrospectively collected their rubella HI titers. Congenital rubella syndrome (CRS) and congenitally infected babies were born from 12 high-risk mothers. In our study, six pregnant women to be immunized by a catch-up program showed a lack of immunity to rubella. The remaining six women had low rubella immunity. Nine acquired rubella from members of their family, including their husband. The incidence of negative HI titer was 25% in women less than 25 years old who delivered during the last 2 years in this hospital. More intensive immunization should be considered to eradicate CRS completely in Japan.

Urinary S-100B Concentrations in Term and Preterm Infants at Risk for Brain Damage

Background: Elevated serum concentrations of S-100B, a 21-kDa protein expressed in astroglial cells, has been used to assess cerebral damage after head trauma, infection, ischemia, and perinatal asphyxia. Objective: As S-100B is eliminated by the kidneys, we investigated the feasibility of measuring S-100B in urine of newborns with severe perinatal asphyxia, and in very low birth weight (VLBW) preterm infants at risk for neurodevelopmental impairment. Methods: We first analyzed urine samples of 8 term or near-term newborns without major medical problems, followed by urine samples of 2 term newborns with severe birth asphyxia, and finally urine samples of 8 VLBW (gestational age 24–28 weeks) infants collected every 4 h for up to 10 days. Results: Urinary S-100B concentrations in 8 term or near-term newborns without major medical problems were consistently <1 µg/l. In 2 term newborns with severe asphyxia (Apgar 0/0/0 and 0/2/4) who subsequently had widespread cerebral damage on magnetic resonance imaging, peak urinary S-100B concentrations on the first day of life were 28.1 and 28.4 µg/l, respectively. In 5/8 VLBW infants, urinary S-100B was >1 µg/l in samples obtained on the first day of life (range 1.2–44.9 µg/l, median 6.8 µg/l). Peak S-100B in urine samples collected during the first 12 h of life were negatively related to gestational age (R_s = –0.882, p = 0.009). Three of the 8 preterm infants had peak urinary concentrations >10 µg/l but neither ultrasound signs of brain damage nor neurodevelopmental delay at 1 year corrected age. Conclusions: The determination of urinary S-100B concentrations might be helpful in term infants with severe asphyxia, while high urinary S-100B concentrations in preterm infants are to be attributed to immaturity.

S100B Protein in Urine of Preterm Newborns with Ominous Outcome

Prematurity is an important cause of perinatal death, and no reliable biochemical/biophysical markers exist to identify newborns with an increased mortality risk. We aimed to use S100B concentrations in urine as an early indicator of risk of neonatal death. We did a cross-sectional study using urine obtained from 165 preterm newborns, of whom 11 suffered neonatal death within the first week, 121 displayed no overt neurologic syndrome, and 33 suffered neonatal hypoxia and intraventricular hemorrhage (IVH) but not ominous outcome. Urine S100B concentrations were determined at four time-points and corrected for gestational age by conversion to multiples of median (MoM) of healthy controls of the same gestational age. Ultrasound imaging was assessed within the first 72 h from birth. In infants that died within the first week, S100B levels in urine were already higher than controls at first urination and increased progressively between the 24 and 96-h time-points. Multiple logistic regression analysis showed a significant correlation between urine S100B protein concentrations and the occurrence of neonatal death. An S100B concentration cut-off of 12.93 MoM at first urination had a sensitivity of 100% and a specificity of 97.8% for predicting an ominous outcome. The positive predictive value was 78.6%, the negative predictive value was 100%. Measurement of urine S100B protein levels in preterm newborns could be useful to identify newborns at higher risk of neonatal death.

Programmed syndrome of hypernatremic hypertension in ovine twin lambs

An increased risk of adult hypertension, obesity, and coronary heart disease occurs in low birth weight or intrauterine growth-restricted newborn infants as a result of fetal programming. Human twins represent a natural model of low birth weight and intrauterine growth restriction because they are significantly smaller at birth than singleton infants because of both earlier delivery and reduced intrauterine growth. Increased blood pressure has been reported in several epidemiologic studies of human twin offspring, although this has not been confirmed in an animal model. Because the sheep pregnancy consists of singleton and twin litters, we sought to determine the impact of ovine twin gestation and twin nursing on the cardiovascular and renal function of the offspring. Newborn lambs (n = 12) were studied at 21 +/- 2 day of life. Both singleton (n = 6) and twin lambs (n = 6) were born to ewes provided ad libitum water and food throughout gestation. After the delivery, ewes were provided ad libitum water and food, and newborn lambs were allowed ad libitum nursing with the maternal ewe. At 15 +/- 2 days of age, the lambs were prepared with vascular and renal catheters and studied at 21 +/- 2 days. After a 2-hour basal period, lambs received an intravenous infusion of hypotonic (0.075 mol/L) NaCl (0.15 ml/kg/hr) for an additional 2 hours. Newborn arterial blood pressure, heart rate, and urine flow were monitored continuously, and arterial blood samples were obtained before, during, and after the infusion. At birth, twin lambs weighed 30% less than singleton lambs (3.5 +/- 0.1 kg vs 5.0 +/- 0.2 kg; P < .05), although 50% less at 21 days (5.2 +/- 0.6 vs 10.8 +/- 1.2 kg). There were marked differences in basal arterial blood values between twin and singleton lambs at 21 days, with twins having significantly increased plasma sodium and systolic, diastolic, and mean arterial pressures and reduced glomerular filtration rates, urine osmolality, osmolar excretion, and osmolar clearance (per kg body weight) compared with singleton lambs. In response to hypotonic saline solution infusion, the plasma composition and blood pressure differences between twin and singleton lambs persisted. These results indicate that ovine twin gestation and nursing markedly reduced body weight at 21 days of age, with evidence of plasma hypernatremia, hypertension, and reduced glomerular filtration rates, which persisted throughout hypotonic saline solution infusion. Consistent with epidemiologic studies of humans, these results demonstrate that gestational/newborn nutrient stress may program hypertension in offspring.

Changes of lipocalin-type prostaglandin D synthase level during pregnancy.

Prostaglandin D (PGD), synthesized by lipocalin-type prostaglandin D synthase (L-PGDS), has marked effects on a number of biological processes, including the prevention of platelet aggregation and the relaxation of vascular smooth muscle. The aim of the study presented here was to examine the significance of L-PGDS in human pregnancy. We measured the concentration of plasma L-PGDS in pregnant and non-pregnant women, and the concentration of L-PGDS in the umbilical cord blood, amniotic fluid and urine of newborns by enzyme-linked immunoabsorbent assay. To determine the localization of L-PGDS, we performed immunohistochemical analysis. To evaluate the usefulness of diagnosis of rupture of membranes (ROM), we determined the concentration of L-PGDS in cervicovaginal secretions. Pregnant women and non-pregnant women had similar L-PGDS concentrations (0.57 +/- 0.13 microg/mL vs 0.53 +/- 0.07 microg/mL). Umbilical cord blood, amniotic fluid and newborn urine contained higher L-PGDS concentrations (1.87 +/- 0.73 microg/mL, 2.62 +/- 0.86 microg/mL, 6.31 +/- 4.62 microg/mL, respectively) than maternal blood. The concentration of L-PGDS in amniotic fluid from 19 weeks onward was significantly greater than that at 15-18 weeks (3.201 +/- 0.384 microg/mL, n = 6 vs 1.735 +/- 0.477 microg/mL, n = 4; P < 0.05). Immunohistochemistry revealed that the amniotic cells of the placenta expressed L-PGDS. The sources of L-PGDS in amniotic fluid are fetus urine and amniotic cells. The concentration of L-PGDS in cervicovaginal secretions with rupture of membrane (ROM) were significantly higher than those without ROM. The measurement of L-PGDS in cervicovaginal fluid was useful in the detection of ROM during pregnancy.

Quantification of arecoline (areca nut alkaloid) in neonatal biological matrices by high-performance liquid chromatography/electrospray quadrupole mass spectrometry.

A high-performance liquid chromatography (HPLC) method with mass spectrometric detection is described for determination of arecoline in newborn meconium, urine and cord serum, using pilocarpine as internal standard. The analytes were extracted from neonatal biological matrices with chloroform/isopropanol (95:5, v/v) at alkaline pH. Extracts were analyzed by HPLC coupled to an electrospray (ESI) interface and a quadrupole mass spectrometer. Chromatography was performed on a C(8) reversed-phase column using 10 mM ammonium acetate (pH 4.3)/acetonitrile (90:10, v/v) as mobile phase. The mass spectrometer was operated in selected ion monitoring mode. The method was validated over the concentration range 0.005-1.00 micro g/g meconium, 0.004-1.00 micro g/mL cord serum and 0.001-1.00 micro /mL urine. Mean recoveries ranged between 86.5 and 90.7% for arecoline in the different biological matrices, with precision always better than 10%. The quantification limits of arecoline were 0.005 micro g/g meconium, 0.004 micro g/mL cord serum, and 0.001 micro g/mL urine. The method was applied to the analysis of neonatal biological matrices to assess eventual fetal exposition to arecoline. Two newborns from Asian mothers who declared areca nut consumption presented arecoline in meconium with concentrations in the range 0.006-0.008 micro g/g; also the urine from one neonate tested positive for the drug.

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.

Increased Urinary S100B Protein as an Early Indicator of Intraventricular Hemorrhage in Preterm Infants: Correlation with the Grade of Hemorrhage

Intraventricular hemorrhage (IVH) is the most common form of cerebral hemorrhage in preterm infants, affecting ∼15–20% (1). Despite accurate postnatal monitoring, IVH is difficult to diagnose during the first 72 h after birth because at this stage, clinical symptoms and radiologic assessment of brain damage may still be silent (2). The availability in these patients of quantitative indicators suggesting subclinical lesions at a time when the monitoring indicators are unable to detect bleeding is therefore important. Furthermore, quantification of the extent of the hemorrhaged lesion could permit the prevention and/or treatment of clinical neurologic damage. S100B is an acidic calcium-binding protein found in the nervous system, where it is concentrated in glial cells (3). The presence of increased S100B in the blood and cerebrospinal fluid (CSF) is a consolidated marker of brain damage in adults and children (4)(5)(6)(7)(8) and has been proposed recently for use in preterm newborns developing IVH (9). We have detected the S100B protein in the urine of preterm newborns under normal conditions and established reference values for the protein at the first urination (10). The present work, extending from the earlier study, investigates urine S100B in preterm newborns developing IVH to offer an indicator for the early detection of IVH. We performed a case-control study on 18 preterm newborns (29–35 weeks of gestation) with IVH in whom urine S100B was measured at first urination (time 0) and at 24 (time 1), 48 (time 2), and 72 h of age (time 3). IVH was diagnosed at 72 h after birth by ultrasound scanning (11): eight infants were classified as grade II (IVH without ventricular dilatation); eight as grade III (IVH with ventricular dilatation); and two as grade IV (IVH with parenchymal lesion). No other ultrasound abnormalities were described at …

Origins of Spurious Organic Acidurias

The diagnosis of inborn errors of organic acid metabolism is based on the assumption that the sudden appearance or elevation of diagnostic, urinary organic acids is directly related to a specific enzymatic defect. The assumption may be misleading because there are instances in which other mechanisms may be responsible. In the rush to get laboratory results out, these factors may not be given sufficient consideration. Age and Dietary Considerations The neonate, because of the immaturity of its physiologic systems, will often show compounds in the urine different from those of older children. Chalmers and Lawson 1(pp 189-190) noted that the effects of diet on organic acid excretion patterns are much greater in newborns than in older children and adults. High levels of 2-oxoglutaric acid are often seen, and elevated levels of fumaric acid are occasionally seen. Both could be partially caused by alterations in the Krebs cycle and acid-base metabolism. Adipic acid is a 6-carbon, medium-chain dicarboxylic acid seen in small amounts in the urine of newborns. The presence of large amounts of the compound is usually indicative of an error of metabolism. Glick and Fischer 2 reported large amounts of adipic acid in urine of children eating gelatins. In that report and in 2 of the 3 cases we observed, adipic acid was the only diagnostic organic acid level elevated. Our third case, a patient with isovaleric aciduria recovering from an episodic attack, showed a sudden appearance of a large amount of adipic acid along with a high level of isovalerylglycine. The adipic acid was traced to Pregestimil (Mead Johnson), a milk formula fortified with medium-chain triglycerides (MCT) in which 75% of the fatty acids originate with a 6-carbon dicarboxyilc acid. In addition to adipic acid, other medium-chain dicarboxylic acids are commonly found in the course of urinary organic acid screening. Usually, these occurrences are not due to inborn errors of metabolism. Dicarboxylic aciduria may be secondary to fasting, diabetic ketoacidosis, anticonvulsant therapy, an MCT-containing diet, and neonatal enzymatic immaturity. 3

Cord Serum Cotinine as a Biomarker of Fetal Exposure to Cigarette Smoke at the End of Pregnancy

This study investigated the association between biomarkers of fetal exposure to cigarette smoke at the end of pregnancy, cotinine in cord serum and in maternal and newborn urine samples, and quantitative measurement of smoking intake and exposure evaluated by maternal self-reported questionnaire. Study subjects were 429 mothers and their newborns from a hospital in Barcelona, Spain. A questionnaire including smoking habits was completed in the third trimester of pregnancy and on the day of delivery. Cotinine concentration in cord serum was associated with daily exposure to nicotine in nonsmokers and with daily nicotine intake in smokers. The geometric mean of cotinine concentration in cord serum statistically discriminated between newborns from nonexposed and exposed nonsmoking mothers, and between these two classes and smokers, and furthermore was able to differentiate levels of exposure to tobacco smoke and levels of intake stratified in tertiles. Urinary cotinine levels in newborns from nonsmoking mothers exposed to more than 4 mg nicotine daily were statistically different from levels in two other categories of exposure. Cotinine concentration in urine from newborns and from mothers did not differentiate between exposure and nonexposure to environmental tobacco smoke (ETS) in nonsmoking mothers. Cord serum cotinine appeared to be the most adequate biomarker of fetal exposure to smoking at the end of pregnancy, distinguishing not only active smoking from passive smoking, but also exposure to ETS from nonexposure.

Cord serum cotinine as a biomarker of fetal exposure to cigarette smoke at the end of pregnancy.

This study investigated the association between biomarkers of fetal exposure to cigarette smoke at the end of pregnancy, cotinine in cord serum and in maternal and newborn urine samples, and quantitative measurement of smoking intake and exposure evaluated by maternal self-reported questionnaire. Study subjects were 429 mothers and their newborns from a hospital in Barcelona, Spain. A questionnaire including smoking habits was completed in the third trimester of pregnancy and on the day of delivery. Cotinine concentration in cord serum was associated with daily exposure to nicotine in nonsmokers and with daily nicotine intake in smokers. The geometric mean of cotinine concentration in cord serum statistically discriminated between newborns from nonexposed and exposed nonsmoking mothers, and between these two classes and smokers, and furthermore was able to differentiate levels of exposure to tobacco smoke and levels of intake stratified in tertiles. Urinary cotinine levels in newborns from nonsmoking mothers exposed to more than 4 mg nicotine daily were statistically different from levels in two other categories of exposure. Cotinine concentration in urine from newborns and from mothers did not differentiate between exposure and nonexposure to environmental tobacco smoke (ETS) in nonsmoking mothers. Cord serum cotinine appeared to be the most adequate biomarker of fetal exposure to smoking at the end of pregnancy, distinguishing not only active smoking from passive smoking, but also exposure to ETS from nonexposure.

Congenital cytomegalovirus infection in a neonatal intensive care unit in brazil evaluated by PCR and association with perinatal aspects.

Cytomegalovirus (CMV) infection is the most common congenital infection, affecting 0.4% to 2.3% newborns. Most of them are asymptomatic at birth, but later 10% develop handicaps, mainly neurological disturbances. Our aim was to determine the prevalence of CMV shed in urine of newborns from a neonatal intensive care unit using the polymerase chain reaction (PCR) and correlate positive cases to some perinatal aspects. Urine samples obtained at first week of life were processed according to a PCR protocol. Perinatal data were collected retrospectively from medical records. Twenty of the 292 cases (6.8%) were CMV-DNA positive. There was no statistical difference between newborns with and without CMV congenital infection concerning birth weight (p=0.11), gestational age (p=0.11), Apgar scores in the first and fifth minutes of life (p=0.99 and 0. 16), mother's age (p=0.67) and gestational history. Moreover, CMV congenital infection was neither related to gender (p=0.55) nor to low weight (<2,500 g) at birth (p=0.13). This high prevalence of CMV congenital infection (6.8%) could be due to the high sensitivity of PCR technique, the low socioeconomic level of studied population or the severe clinical status of these newborns.

A tobacco-specific carcinogen in the fetus.

A tobacco-specific carcinogen, 4-(methylnitrosamino)-1-(3-pyridyl)-1-butanol (NNAL), and its metabolite, 4-[(methylnitrosamino)-1-(3-pyridyl)but-1-yl]beta-O-D-glucosiduronic+ ++ acid (NNAL-Gluc), have been found in the urine of newborns whose mothers smoked during pregnancy. We set out to determine whether this carcinogen is present in the fetus in early pregnancy. Cell-free amniotic fluid (AF) was obtained through routine amniocentesis for prenatal genetic studies from groups of smokers and non-smokers. NNAL and NNAL-Gluc were quantified by previously published methods. A history of smoking was confirmed by assays for cotinine plus N-beta-D-glucosiduronosyl-(S)-(-) cotinine inner salt (cotinine-Gluc) in AF. NNAL was detected in the AF of 11/21 (52.4%) of smokers and in 2/30 (6.7%) of non-smokers, a statistically significant difference (p=0.0006). There was not convincing evidence of NNAL-Gluc in the AF. This study documents for the first time that the tobacco-specific carcinogen NNAL is present in the fetus in early pregnancy. Further rigorous epidemiological studies are needed to determine whether the offspring of smoking mothers have an increased lifetime risk of cancer.

Voiding pattern in healthy newborns.

A 4-hour observation period has been used in infants to investigate suspected bladder dysfunction. The aim of the present study was to extend the usefulness of this protocol by establishing reference values for voiding frequency, intervals, volumes, and residual urine in healthy newborns. The study included 51 healthy newborns, 26 girls and 25 boys, aged 3 to 14 days. During a 4-hour period, all micturitions and residuals were recorded as well as feeding, sleeping, crying, and defecations. The observation was completed with the child undressed to observe the urinary stream during one void. Different provocation tests were tried to induce urinary leakage. All newborns voided with a stream, about once per hour, with a median volume of 23 mL. For each voiding parameter, there was a large inter- and intra-individual variability. Double voidings were common as well as sizable residual volumes. The diuresis was about six times higher than in healthy school children. The healthy newborns did not leak during provocation tests such as manual compression of the bladder. Neurourol. Urodynam. 19:177-184, 2000.

Pilot study of gas chromatographic–mass spectrometric screening of newborn urine for inborn errors of metabolism after treatment with urease

Gas chromatographic–mass spectrometric (GC–MS) techniques for urinary organic acid profiling have been applied to high-risk screening for a wide range of diseases, mainly for inborn errors of metabolism (IEM), rather than to low-risk screening or mass screening. Using a simplified procedure with urease-pretreatment and the GC–MS technique, which allows simultaneous determination of organic acids, amino acids, sugars and sugar acids, we performed a pilot study of the application of this procedure to neonatal urine screening for 22 IEM. Out of 16 246 newborns screened, 11 cases of metabolic disorders were chemically diagnosed: two each of methylmalonic aciduria and glyceroluria, four of cystinuria, and one each of Hartnup disease, citrullinemia and α-aminoadipic aciduria/α-ketoadipic aciduria. The incidence of IEM was thus one per 1477, which was higher than the one per 3000 obtained in the USA in a study targeting amino acids and acylcarnitines in newborn blood spots by tandem mass spectrometry. Also, 227 cases were found to have transient metabolic abnormalities: 108 cases with neonatal tyrosinuria, 99 cases with neonatal galactosuria, and 20 cases with other transient metabolic disorders. Two hundred and thirty-eight cases out of 16 246 neonates (approximately 1/68) were thus diagnosed using this procedure as having either persistent or transient metabolic abnormalities.

Characterization of the isoenzyme profile of beta-N-acetylhexosaminidase in the urine of newborns.

The urinary isoenzymes of beta-N-acetylhexosaminidase (Hex) in newborn infants were characterised by chromatography, electrophoresis, thermodynamic analysis and through substrate specificity. No qualitative difference was found for the major Hex A and Hex B isoenzymes between full-term or premature newborns and adults, although in the latter group the relative proportion of Hex B is much lower (18.5 +/- 2.7% vs. 36.3 +/- 1.0%). An additional minor enzyme form was found in some premature newborns, which eluted from the DEAE-cellulose column at a higher concentration of NaCl than Hex A and, like this isoenzyme, is able to hydrolyse 4-methylumbellipheryl-2-acetamido-2-deoxy-beta-D-glucopyranoside-6 -sulphate, which would suggest that it has alpha subunits in its molecule. These results do not confirm the hypothesis of other authors about the existence of a unique fetal Hex isoenzyme in neonatal urine which eluted before the application of the NaCl gradient, similarly to the Hex B.

Frigen II improves the reliability of measurement of interleukin‐1 related substances in amniotic fluid

To investigate the role of interleukin-1 related substances in amniotic fluid in normal term labor without intrauterine infection. Amniotic fluid samples were collected from forty-one patients with various backgrounds. A novel pre-assay treatment using Frigen II was introduced to improve the recovery rates of cytokines, i.e., interleukin-1alpha, interleukin-1beta and interleukin-1 receptor antagonist, prior to ELISA assay. Urine samples from newborn infants were also tested. The concentrations of interleukin-1alpha, interleukin-1beta and interleukin-1ra were significantly higher in samples from normal vaginal delivery. The higher levels of interleukin-1alpha were also observed in samples from preterm labor without infection. Preterm infants produced more of interleukin-1 receptor antagonist in urine compared with term infants. This study provides evidence of the possible involvement of interleukin-1 related substances in labor without signs of infection. The data from newborn urine suggests that amniotic interleukin-1ra originates from the fetus. However, amniotic fluid interleukin-1alpha and interleukin-1beta may be derived from maternal tissue, such as decidua.

Newborn Screening by Tandem Mass Spectrometry: A New Era

Soon after Guthrie (1) expanded newborn screening by adding galactosemia, maple syrup urine disease (MSUD), and homocystinuria to the original screening for phenylketonuria (PKU), he realized that screening would be more efficient and comprehensive if a single assay could be used to detect several disorders rather than the system of a separate bacterial assay for each disorder that he had developed. He tried many ways to make such a single assay–using multiple inhibitors and different strains of bacteria–but nothing worked, so he abandoned the idea. Others had the same idea but used chromatography rather than bacterial assays (2)(3). Unfortunately, paper chromatography was insufficiently sensitive for screening newborn blood within the first days of life when the specimen is collected. To compensate for this shortcoming and to further expand the coverage of disorders, paper or thin-layer chromatography has been used for screening newborn urine (4). But here again, chromatography has had substantial disadvantages. First, an additional specimen is required because urine cannot replace blood in detecting either PKU or congenital hypothyroidism, the two indispensable disorders in screening. Second, the urine specimen must be collected by a parent or physician after nursery discharge, introducing a logistical problem. Third, urine varies widely in concentration, producing many false-positive results in the more highly concentrated specimens. This leads to otherwise unnecessary, anxiety-provoking requests for repeat specimens. Conversely, false-negative findings may result from dilute specimens. Finally, many of the disorders identified in urine, such as histidinemia, iminoglycinuria, and Hartnup disorder, are benign (4). Consequently, newborn urine screening based on chromatography has been discontinued in two of the three places in which was introduced, Australia (5) and Massachusetts, remaining only in Quebec (6). Thus, screening programs continue to rely on the “one test-one …