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J U Leititis

Publications and source records attributed to J U Leititis.

At least 19 recordsLinked to original sources

Circadian variations of urinary electrolyte concentrations in preterm and term infants.

OBJECTIVES: To determine whether a circadian variation of urinary excretion of calcium and phosphorus exists in preterm infants. STUDY DESIGN: We studied 70 newborn infants (median birth weight 1920 gm, range 660 to 3550 gm; median gestational age 34 weeks, range 25 to 42 weeks) at a median postmenstrual age of 36 weeks (range 32 to 42 weeks). Within a period of 24 hours, four urine specimens were collected during 6-hour periods. The concentrations of calcium, phosphorus, sodium, potassium, and creatinine were determined and creatinine quotients were calculated for each specimen. RESULTS: No clinically relevant circadian variation in urinary excretion for any of these minerals was found. CONCLUSION: If spot urine specimens are used to monitor calcium and phosphorus balance in preterm infants, the time of the day these are collected is not important.

Circadian Rhythm

Urinary excretion of adenosine deaminase binding protein in neonates treated with tobramycin.

The potential tubulotoxicity of tobramycin and cefotaxim were assessed in neonates by measuring the urinary level of adenosine deaminase binding protein (ABP) and urinary alpha 1-microglobulin and beta 2-microglobulin. In a prospective study, 33 neonates who received tobramycin and cefotaxim for suspected neonatal sepsis were compared with 48 untreated newborns during the first 10 days of life. The urinary concentrations of ABP and its excretion rates, corrected for body weight and body surface area, were significantly increased from the 1st day of treatment. Urinary alpha 1-microglobulin and beta 2-microglobulin were not elevated under tobramycin and cefotaxim during the first 2 days of treatment. We conclude that ABP may be a sensitive marker for the detection of proximal renal tubular injury during tobramycin and cefotaxim treatments of neonates. The increase in urinary ABP which occurs before an elevation of urinary alpha 1-microglobulin and beta 2-microglobulin may reflect earlier structural than functional alterations. However, since none of the treated infants had signs of electrolyte disorders or glomerular dysfunction, the clinical relevance of ABP measurement should be reevaluated.

Anti-Bacterial Agents

Zinc deficiency in an exclusively breast-fed preterm infant.

UNLABELLED: A formerly premature, exclusively breast-fed infant with severe zinc deficiency syndrome is presented. He showed the characteristic erosive skin changes, including alopecia, as seen in acrodermatitis enteropathica. In addition, he manifested a failure to thrive and irritability. The diagnosis was confirmed by reduced serum levels of zinc (2.3 mumol/l) and alkaline phosphatase (45 U/l). We consider the reduced zinc supply in the breast milk (5.7 mumol/l) as the most likely cause of the disease. Therapy consisted of oral zinc supplements (50 mumol/kg/day) for a period of 30 weeks. Symptoms and laboratory values normalized completely and did not recur on a normal diet. CONCLUSION: A diet of breast milk can, in rare circumstances, cause insufficient zinc intake resulting in severe zinc deficiency syndrome with characteristic dermatological features. Therapy consists of temporary oral zinc supplementation at a daily dose of 50 mumol/kg.

Alkaline Phosphatase

Low birth weight and nosocomial infection of neonates in a neonatal intensive care unit.

A one year prospective surveillance of nosocomial infections (NI) in a neonatal intensive care unit (NICU) was performed. Among 229 neonates the infection rate was 27.1%, the infection proportion 20.1%, and the incidence density 21.9 infections per 1000 patient days. Infants were stratified into four birth weight categories. Degrees of infection ranged from 44.4% in the < or = 1000 g group to 10.1% in the > 2500 g group. Differences between the groups were statistically significant (P < 0.01). The mean birth weight of infants with NI was significantly lower than that of infants without NI (1711 g, SD +/- 841 g vs. 2213 g, SD +/- 896 g; P < 0.01). Mortality of < or = 1000 g babies was 44.4 and 7.6% in > 2500 g neonates. Major sites of infection were pneumonia (32.3%), blood-stream infections (27.4%), infections of the skin, and surgical site infections (11.3% each). The predominant pathogen was Staphylococcus aureus (24.2%) whilst Gram-negative bacteria accounted for 22.7% of the total. Other major infective agents were Staphylococcus epidermidis, Escherichia coli, and Group B streptococci. It is concluded, that low birth weight was a major risk factor for the acquisition of NI in the observed NICU population.

Bacterial Infections

von Willebrand factor-collagen binding activity is increased in newborns and infants.

von Willebrand factor (vWF) antigen (vWF:Ag) and vWF-collagen binding activity (vWF:CBA) were measured in plasma by parallel quantitative ELISAs in normal newborns and infants (n = 71). The medians for vWF:Ag (IU/ml) and vWF:CBA (U/ml), respectively, were 1.46 and 1.91 for 2-7 day-old (n = 43), 1.22 and 1.40 for 2-4 week-old (n = 14), 1.22 and 1.15 for 2-6-month-old (n = 14) infants and 0.98 and 1.08 (n = 36) in normal adults. Elevated levels of vWF:Ag, but particularly vWF:CBA were seen for up to 4 weeks of life reaching adult levels between 2 and 6 months of life. The elevated levels of the vWF parameters indicate that caution should be exercised when interpreting laboratory data and diagnosing von Willebrand disease in newborns and young infants and warrant the use of age-specific reference ranges. The efficient haemostasis observed during early neonatal life may in part be due to the increased ability of vWF to interact with collagen.

Collagen

[Kidney biopsy].

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Biopsy, Needle

[Preventive and therapeutic use of intravenous administration of immunoglobulins in intensive care patients in pediatrics].

The intravenous infusion of immunoglobulin preparations (ivIg) still is no established mode of therapy for neonatal septicemia or for the prevention of nosocomial infections in premature infants. Some recent studies show a decrease in nosocomial infections by ivIg infusions. However, a significant reduction in infections by any specific pathogen has not been demonstrated; the specific antibody content of the ivIg preparations in relation to these pathogens has not been examined. No statistical differences were found regarding duration of hospitalization, morbidity, or mortality of premature infants. ivIg seem to have positive effects on neonatal isoimmune thrombocytopenia or on thrombocytopenia caused by maternal immunothrombocytopenic purpura. There is also evidence that ivIg could have a positive effect on the course of Guillain-Barré syndrome, although this has not been proven for children.

Autoantibodies

Critical care in uraemic children.

The special problems posed by renal disease have to be considered when a uraemic child requires intensive care. This report gives an overview on the problems of dialysis treatment, circulatory support, infectious complications, coagulation disorders and increased intracranial pressure.

Anti-Bacterial Agents

RARE-MR-urography in the diagnosis of upper urinary tract abnormalities in children.

RARE-MR-urography (Rapid Acquisition with Relaxation Enhancement) is a fast MR imaging technique (6.4 s/acquisition) that selectively depicts fluid by heavy T2-weighting. From 9/1989 to 11/1990, RARE-MR urograms were prospectively evaluated in the diagnosis of upper urinary tract abnormalities in 55 children. The method is performed in several planes and combined with a coronal, T1-weighted spin-echo sequence. Forty out of 42 kidneys with dilated renal pelvis, and 21 out of 24 dilated ureters were identified, only the mildly dilated ones were missed. Even in non-functioning kidneys the urinary tract was clearly depicted by RARE-MR-urography. However, no differentiation could be made with this technique between vesicoureteral reflux and non-refluxing dilatation of ureter and/or renal pelvis. All 19 pelviureteric obstructions and all eight renal duplications with a dilated segment were identified. RARE-MR-urography is a new tool for diagnosing urinary tract abnormalities in children without having to employ ionizing radiation, contrast media, or general anesthesia. A dilated urinary tract can be shown in one image displaying the entire urinary system, similar to excretory urography. The technique is presently not able to provide the information of voiding cystourethrography or renal scintigraphy, nor is it as easy to perform as ultrasound. However, in certain cases it may replace excretory urography.

Adolescent

[RARE-MR urography: a rapid MR tomographic imaging procedure for the diagnosis of urinary tract malformations in childhood].

RARE-MR urography (so called "water-pictures") is a fast MR imaging technique that selectively depicts fluid without contrast application. Acquisition time is 6.4 s per slice with 1 excitation, or 23 s per slice with 2 averages respectively. From Sept. 1989 to April 1990 24 children with anomalies of the urinary tract have been examined each by RARE MR urography and one T1-weighted spin-echo sequence. Independent of excretory function, the technique can show dilated calices and renal pelvis, pelviureteric obstruction, renal duplication, and megaureter. However, it cannot distinguish between vesicoureteric reflux and obstructive megaureter. Our first results suggest that RARE MR urography combined with ultrasound, reflux cystography and isotope nephrography, can replace excretory urography in certain circumstances--or at least postpone it to the preoperative phase.

Adolescent

Evaluation of local renal function in newborn infants under tobramycin therapy.

Aminoglycosides (AG) provided for less than 5 days to newborn infants do not produce a marked disturbance of glomerular filtration rate (creatinine clearance) or tubular sodium handling (fractional sodium excretion). However, transient disturbances of proximal tubular cell functions can be noted: the excretion of N-acetylglucosaminidase, a lysosomal enzyme, is elevated, and mature not premature infants show a decreased tubular reabsorption of low-molecular-weight proteins during AG treatment. Preliminary investigations show an increased excretion of villin, a structural protein of proximal tubular cells, and a decreased secretion of Tamm-Horsfall protein by the cells of ascending limb of Henle and early distal tubule.

Aminoglycosides

Cyclosporine inhibits renal uric acid transport in renal transplants not in children treated for nephrotic syndrome.

Children with various grades of renal insufficiency (CON group) maintained uric acid excretion over a range of glomerular filtration rate (GFR) from 27 to 160 ml/min*1.73m2 despite a decreased filtered load which was paralleled by glomerular filtration of uric acid. This was achieved by a compensatory decrease of net uric acid reabsorption (TUA) and an increasing fractional excretion of uric acid (FEUA) with decreasing GFR. Although there was a decreased GFR in the group of children after transplantation (NTx group) there was no difference in TUA and FEUA between the NTx group and the CON group. Uric acid transport was not affected in children treated with Cyclosporine (CyA) for nephrotic syndrome (NEPH group) compared to the CON group. Decreased fractional phosphate reabsorption in the NTx group suggests proximal tubule damage associated with disturbed uric acid handling. Under conditions of water diuresis hyperuricemia seen in NTx may result from an indirect effect of renal ischemic damage due to the transplantation procedure causing disturbance of proximal tubular uric acid (active) secretion/reabsorption.

Adolescent