Alveolar recruitment promotes homogeneous surfactant distribution in a piglet model of lung injury

Uneven distribution of exogenous surfactant contributes to a poor clinical response in animal models of respiratory distress syndrome. Alveolar recruitment at the time of surfactant administration may lead to more homogeneous distribution within the lungs and result in a superior clinical response. To investigate the effects of three different volume recruitment maneuvers on gas exchange, lung function, and homogeneity of surfactant distribution, we studied 35 newborn piglets made surfactant deficient by repeated airway lavage with warm saline. Volume recruitment was achieved by either a temporal increase in tidal volume or an increase in end-expiratory pressure during surfactant administration, yielding an increase in dynamic compliance of the respiratory system of 77% in the first group and an increase in functional residual capacity of 108% in the second group. A third group of piglets (all n = 7) received a combination of both volume recruitment maneuvers, with increases in dynamic compliance of the respiratory system of 100% and in functional residual capacity of 192%. Those animals subjected to increased tidal volume showed an improved surfactant response in terms of oxygenation, ventilation, lung volumes, lung mechanics, and homogeneity of surfactant distribution. Increased end-expiratory volume augmented the surfactant effect only to some extent. The combination of both volume recruitment maneuvers, however, needed lung volumes beyond total lung capacity (approximately 56 mL/kg), thus probably inducing early sequelae of ventilator-induced lung injury. We conclude that volume recruitment by means of increased tidal volumes at the time of surfactant administration leads to a superior surfactant effect owing to more homogeneous surfactant distribution within a collapsed lung.

Frequency, natural course, and outcome of neonatal neutropenia

OBJECTIVE

We studied the frequency, onset, duration, and prognosis of neutropenia in a neonatal hospital population to define subgroups of neonates who might benefit from cytokine therapy.

STUDY DESIGN

The study comprised of 2 parts: in a first retrospective study (I), clinical data of neonates with sepsis (n = 168) were analyzed; in a second retrospective and prospective study (II), clinical data of neonates with neutropenia (n = 131) were studied. In study I, the analysis focused on septic neonates with and without neutropenia, and in study II, on neutropenic neonates with and without primary infection. In the prospective part of study II, granulocyte colony-stimulating factor (G-CSF) plasma concentrations were analyzed in neutropenic neonates (n = 32).

RESULTS

Thirty-eight percent of septic neonates were neutropenic. Neutropenia lasted <24 hours in 75% of these patients. It was recorded before or on the day of the clinical onset of sepsis in 87% of patients. The overall incidence of neutropenia was 8.1%. Seventy-two percent of these neutropenic episodes occurred in patients without infection at the time of diagnosis of neutropenia. In the latter patients, the risk of infection secondary to neutropenia was 9%, affecting only premature neonates. Neutropenic episodes without infection were of longer duration and were accompanied by lower G-CSF plasma concentrations than were episodes associated with infection. The percentage of neutropenic episodes primarily associated with infection was higher in VLBW neonates than in term neonates. Likewise, the risk of infection secondary to neutropenia (27%) and the mortality attributable to infection and neutropenia (28%) were significantly higher than in term newborns.

CONCLUSION

Considering the priming time for induction of neutrophilia, G-CSF therapy in neonates presenting with severe bacterial infection and neutropenia may be too late. In contrast, neutropenic very low birth weight neonates without primary infection might benefit from prophylactic G-CSF treatment.neonatal sepsis, neutropenia, granulocyte colony-stimulating factor.

Effect of therapeutic concentrations of nitric oxide on bacterial growth in vitro

OBJECTIVES

Besides its vasodilative actions, nitric oxide (NO) is also involved in host defense on a cellular level. We studied the antimicrobial properties of NO in concentrations used with inhaled NO therapy for the treatment of pulmonary hypertension in neonates.

DESIGN

In vitro study of bacterial growth of five species, with and without NO exposure.

SETTING

Level IV neonatal intensive care unit at a university children's hospital.

SUBJECTS

In vitro bacterial cultures.

INTERVENTIONS

We tested ten different strains of five bacterial species (Staphylococcus aureus, Staphylococcus epidermidis, group B streptococcus [GBS/Streptococcus agalactiae], Escherichia coli, and Pseudomonas aeruginosa), derived from the tracheal isolates of ventilated premature and term infants. Cultures were exposed to three different concentrations of NO (40, 80, and 120 parts per million [ppm]) and bacterial growth was compared with the same strains incubated in ambient air for 24 hrs. After incubation (with or without NO), colony-forming units were counted.

MEASUREMENTS AND MAIN RESULTS

Bacterial growth of S. aureus, E. coli, and P. aeruginosa was not reduced with the NO concentrations applied. The number of colony-forming units of S. aureus increased at 80 ppm of NO. Growth of S. epidermidis and GBS was significantly affected at 120 ppm, resulting in decreased numbers of colony-forming units as compared with controls exposed to ambient air.

CONCLUSIONS

We conclude that NO has a selective bacteriostatic effect on some of those bacteria most commonly cultured in tracheal specimens of premature infants and neonates. This effect appears to be dose-dependent and occurs in the upper range of dosages used with inhaled NO therapy. However, in the range of dosages applied in ongoing controlled trials of inhaled NO in neonates and premature infants (1 to 80 ppm), a bacteriostatic effect of NO is not to be expected.

Plasma levels and gene expression of granulocyte colony-stimulating factor, tumor necrosis factor-alpha, interleukin (IL)-1beta, IL-6, IL-8, and soluble intercellular adhesion molecule-1 in neonatal early onset sepsis

Bacterial sepsis is still a leading cause of neonatal morbidity and mortality. Early onset sepsis in particular, presents with a different clinical course and involves other pathogens than sepsis later in life. In this study, plasma concentrations and mRNA expression of granulocyte colony-stimulating factor (G-CSF), tumor necrosis factor-alpha (TNF-alpha), IL-1beta, IL-6, IL-8, and soluble intercellular adhesion molecule-1 (sICAM-1) of neonates with early onset sepsis were evaluated in cord blood and during the first days of life. Irrespective of prematurity, plasma levels of G-CSF, TNF-alpha, IL-1beta, IL-6, and IL-8, but not sICAM-1, were excessively elevated in septic neonates when compared with both healthy infants and infants with clinically suspected but not confirmed sepsis. Compared with the corresponding maternal levels, neonatal cytokine cord plasma levels were likewise highly elevated, indicating the endogenous cytokine production by the neonate. With the exception of TNF-alpha, mRNA expression in blood cells from septic infants was, however, not more frequently detectable than in those from nonseptic patients. Cytokine levels decreased significantly within the first days of life, whereas levels of sICAM-1 and C-reactive protein increased during the same time period. In summary, in contrast to C-reactive protein and sICAM-1, cord blood plasma levels, but not the presence of mRNA, of G-CSF, TNF-alpha, IL-1beta, IL-6, and IL-8 can predict neonatal early onset sepsis with a high sensitivity and specificity. Cell types other than blood cells are likely to contribute considerably to the high cytokine production in septic newborns.

Effect of inhaled nitric oxide on intrapulmonary right-to-left-shunting in two rabbit models of saline lavage induced surfactant deficiency and meconium instillation

Marked hypoxia secondary to intrapulmonary right-to-left shunting is a characteristic of respiratory failure in human neonates and can sometimes be complicated by additional extrapulmonary right-to-left shunting. To investigate the effect of inhaled nitric oxide (iNO) on intrapulmonary shunting, two typical pulmonary diseases of the newborn (respiratory distress syndrome and meconium aspiration) were reproduced in 32 mechanically ventilated rabbits weighing approximately 2 kg each. After tracheotomy, catheters were inserted into a jugular vein, a carotid artery and the right ventricle (to measure systolic right ventricular pressure [SRVP] and mixed venous oxygen content for calculation of shunt by Fick equation). Repeated airway lavages (LAV) with normal saline or repeated instillations of a suspension of human meconium (MEC) were continued until both the a/A-ratio was < or =0.14 and a peak inspiratory pressure > or =22 mbar was needed to keep the tidal volume constant at 10 ml/kg of body weight. Measurements of shunt, SRVP, systolic systemic pressure, physiological dead space, tidal volume and a ventilation index were performed before and after completion of lung damage and at 20 and 60 min after administering iNO at 80 ppm. Four groups of rabbits were studied (n=8 in each group): LAV control and intervention, Mec control and intervention. 60 min after starting iNO, there was a decrease in shunt (LAV: 67.6%+/-[SD] 11.3% vs 56.2+/-16.4, P=0.05; MEC: 52.6+/-6.3 vs 44.3+/-8.3, P < 0.05), in SRVP (LAV: 29.7 mmHg +/-10.1 mmHg vs 20.0+/-8.2, P < 0.01; MEC: 25.1+/-4.4 vs 22.3+/-5.0, P=0.46) and in dead space (% of tidal volume, LAV: 32.7%+/-10.5% vs 25.9+/-10.1, P < 0.01; MEC: 26.1+/-16.6 vs 18.9+/-10.1, P=0.05). These results demonstrate that iNO decreases intrapulmonary shunt (as well as SRVP and dead space). We suggest that iNO may be beneficial in human newborns with severe respiratory failure even if no extrapulmonary shunting via ductus or foramen ovale is apparent.

Interventional neuropediatrics: treatment of dystonic and spastic muscular hyperactivity with botulinum toxin A

Therapeutic effect of botulinum toxin A was studied in a group of pediatric patients (n = 28) aged between 6 months and 18 years. The patients were diagnosed with cervical dystonia (n = 6), adductor spasm of the hip (n = 8), spastic drop foot (n = 7) and various other focal motor problems associated with spastic muscular hyperactivity (n = 7). The mean dose of botulinum toxin A (Dysport) used to inject into the affected muscle was 22 U/kg body weight. Reduced muscular hyperactivity with a significant increase in joint mobility was achieved for dystonic (p < 0.0001) as well as for spastic conditions in patients with adductor spasm (p < 0.0002). For these patients the improved joint mobility represented a significant benefit for both daily activities and nursing care. Local paresis and local hematoma were observed in 1/28 and 1/28 patients, respectively; 1/28 patients developed a secondary non-response. However, apart from these side effects, no other adverse reactions to botulinum toxin A treatment were recorded during the treatment and observation period (12-64 months). Our results suggest that botulinum toxin A represents an effective and safe therapeutic substance for the treatment of pediatric patients suffering of focal motor problems due to dystonic or spastic muscular hyperactivity.

[Reversal of a right-left shunt and permanent improvement of oxygenation by inhalation of nitrogen monoxide in a premature infant with lung hypoplasia and asphyxia]

We report the case of a 29 weeks gestation female premature infant who suffered from severe postnatal asphyxia following spontaneous vaginal delivery. Prenatally lung hypoplasia due to prematurely ruptured membranes with subsequent oligohydramnios was suspected sonographically. Echocardiography revealed right-to-left shunting via PDA and foramen ovale, in addition to that tricuspid incompetence with a pulmonary arterial pressure gradient of 40 mmHg was demonstrated. At an oxygenation index (OI) of 34, an arterio-alveolar oxygen difference (AaDO2) of 639 mmHg, an FiO2 of 1.0 and a maximal paO2 of 37 mmHg during high frequency ventilation (HFV), we applied inhaled nitric oxide (up to 70 ppm) for a duration of approximately 30 hours. Within two hours the inspiratory oxygen concentration could be weaned to an FiO2 of 0.21, mean airway pressures were reduced markedly. Echocardiographically tricuspid incompetence had disappeared, the PDA was closed and now left-to-right shunting across the foramen ovale was demonstrated. The infant was extubated on day 5 and subsequently had oxygen requirements up to an FiO2 of 0.3 during spontaneous breathing for 20 days.

Fatal sepsis caused by Corynebacterium amycolatum in a premature infant

Corynebacterium amycolatum has not been reported as a cause of human infections up to now, but usually the bacterium is misidentified in clinical specimens as Corynebacterium xerosis. We report the first case of neonatal sepsis due to Corynebacterium amycolatum with a fatal outcome in a premature infant.

Bacterial tracheitis caused by Corynebacterium diphtheriae

Diphtheria has become a rare disease in Germany. We report on an unimmunized 3.5-year-old German girl with a 7-day history of respiratory distress and fever, presenting a clinical picture mimicking typical bacterial tracheitis without pharyngeal and laryngeal manifestation. Diagnosis of diphtheria was not made until culture of tracheal secretions yielded growth of a toxigenic strain of Corynebacterium diphtheriae. The patient died from toxic cardiac failure despite treatment with diphtheria antitoxin. This is the second reported case of isolated bacterial tracheitis caused by Corynebacterium diphtheriae.

CONCLUSION

The observation of a lethal course of diphtheric tracheitis emphasizes the paramount importance of immunization against diseases like diphtheria.

Primary treatment of propionic acidemia complicated by acute thiamine deficiency

Propionic acidemia is often manifested during the neonatal period with vomiting, failure to thrive, lethargy, and hyperammonemic coma when catabolism is prolonged. Mild lactic acidosis frequently accompanies metabolic decompensation. We present two patients with propionic acidemia whose initial manifestation was complicated by severe lactic acidosis caused by thiamine deficiency, which resulted from an inadequate supply of, and an increased need for, thiamine during metabolic stress. To prevent acute thiamine deficiency, we propose early vitamin supplementation during treatment of any severe metabolic decompensation accompanied by insufficient food intake.

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.

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.

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.

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.

Zinc deficiency in an exclusively breast-fed preterm infant

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.

[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.

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.

[Treatment of obstruction and thrombosis due to central venous catheterization]

Thrombolytic treatment with urokinase (5000 U/ml) or streptokinase can restore patency in central venous catheters occluded by thrombosis. In pediatric patients preferable urokinase should be used. The therapy in case of catheter-induced central venous thrombosis is a continuous urokinase infusion (125,000 U/1.73(2)/h) for about 3 to 8 days, followed by a long-term heparinization. The treatment in persistent withdrawal occlusion is significantly shorter, a few hours of systemic lysis are sufficient. The treatment of choice in case of chemical obstructions in patients with long-term parenteral nutrition is the injection of 0.1 N HCl in combination with Heparin. By these procedures most of obstructed central venous catheters can be reopened and maintained in place. This preserves the count of possible catheter implantation sites.

[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.

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.

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.

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.

[Treatment of renal anemia with recombinant human erythropoietin]

Anemia is an almost invariable feature of chronic renal failure and is particularly severe in children treated by long-term hemodialysis. Recombinant human erythropoietin (rhEPO) offers entirely new aspects in the treatment of renal anemia. This report presents three patients on maintenance hemodialysis aged 10, 10/10 12, and 18 years who were treated with rhEPO. Two suffered from hemochromatosis secondary to multiple transfusions. 100 U/kg rhEPO were administered three times weekly, and venesection after dialysis was performed when a target hematocrit value of 30% was achieved. Hematocrit, reticulocyte-counts and hemoglobin rose within 3 to 6 weeks after initiation of therapy in all patients. Serumferritin levels declined significantly in the two patients with hemochromatosis. No deterioration of the metabolic status (i.e. increase of blood urea nitrogen, serum-creatinine, -phosphate or -potassium) could be detected. Therapy had to be discontinued in one patient who experienced hypertensive ceisis. This patient, however, had suffered from severe hypertension prior to rhEPO therapy. Blood pressure remained stable in the other patients. We conclude that renal anemia can be effectively treated by rhEPO in children. Increase of blood pressure may necessitate discontinuation of therapy especially in primary hypertensive patients. Extensive studies are necessary to eluciate long-term effects of rhEPO in children.

Serum creatinine and creatinine clearance in healthy neonates and prematures during the first 10 days of life

Normal serum creatinine (Scr) and creatinine clearance (Ccr) values during the first 10 days of life were obtained in 63 very premature (28-32 weeks of gestation), premature (33-37 weeks) and term infants (38-42 weeks). Scr fell, and Ccr rose less markedly in the very premature infants. Scr was 80 mumol/l on the 1st day of life both in very premature and premature infants, and 77 mumol/l in full-term neonates. After 10 days, Scr was 73, 53 and 35 mumol/l respectively. There was an exponential correlation between Ccr and gestational age, indicating rapid maturation of glomerular function.

Microproteins in amniotic fluid as an index of changes in fetal renal function during development

Protein content and protein composition were studied in amniotic fluid obtained from 171 healthy pregnant women between the 16th and 38th week of gestation, using microgradient gel electrophoresis to separate proteins according to their molecular size into albumin (68 KD), proteins of low molecular weight (LMW proteins, less than 68 KD), and proteins of high molecular weight (HMW proteins, greater than 68 KD). Additionally alpha-1-microglobulin (alpha-1-MG, 33 KD) and beta-2-microglobulin (beta-2-MG, 11,8 KD) were analysed as micromolecular marker proteins. Concentrations of LMW proteins were 0.15-0.22 g/l, of alpha-1-MG 28.4-34.5 mg/l, and of beta-2-MG 7.2-11.6 mg/l during the second trimester of gestation, and thereafter decreased progressively to 0.03 g/l, 14.1 mg/l and 2.4 mg/l respectively near term. The same developmental trends were confirmed by calculating the protein/creatinine ratios in amniotic fluid. The concentrations of LMW proteins found in the first postnatal urine of 73 healthy infants born prematurely or at term were similar to those in amniotic fluid of corresponding fetal age. Concentrations of albumin and HMW proteins in postnatal urine were about 5% and 15% respectively when compared with amniotic fluid concentrations. No strong correlation existed between gestational age and either of the analysed proteins which would allow accurate assessment of fetal maturation by protein analysis in amniotic fluid. It is concluded that fetal urinary excretion is the major determinant of the microprotein content of amniotic fluid. Microproteins seem to reflect an increasing tubular reabsorption capacity, which accelerates rapidly after the second trimester of gestation.

Effect of a modified fluid therapy on renal function during indomethacin therapy for persistent ductus arteriosus

A rehydration with 7 ml/kg/h for six hours prior to indomethacin administration prevented the adverse effects of this drug on renal function in prematures with persistent ductus arteriosus. During the 36 hour observation period after indomethacin administration, no significant changes in serum creatinine, sodium, and potassium concentrations, or urinary flow, creatinine clearance, or filtered sodium could be detected. The only significant finding was a reduction in fractional sodium excretion. One can assume that this beneficial effect of the fluid load is due to a suppression of some parts of the vasoconstrictor mechanisms, which are responsible for the deterioration of renal function in newborns during indomethacin therapy. Using this modified fluid regimen, no cardiovascular side effects were noticed, a closure of the duct was achieved in 7 of 10 treatment courses.

[Disorders of kidney function and acute kidney failure in newborn infants]

Compromised kidney function in the perinatal period has been increasingly recognized during recent years, and acute renal failure is a frequent clinical situation in neonatal intensive care units. Renal underperfusion due to various prerenal conditions is assumed to be the most common cause of renal failure in neonates. With rapid restoration of renal blood flow, prerenal failure is completely reversible in the early course of the disease. If adequate treatment is delayed, however, structural damage to the kidneys by prolonged ischemia will ensue leading to a poor prognostic outcome. This review, therefore, mainly focuses on early diagnosis of disturbed neonatal kidney function and prophylactic therapeutical aspects which may be of particular benefit for critically ill newborns at high risk for developing acute renal failure.

[Developmental physiologic aspects of volume and sodium regulation in premature and mature newborn infants]

Concentrations of sodium and creatinine were measured in serum and time collected urine samples of 72 newborn infants in the first ten days of life. Creatinine clearances, fractional and absolute sodium excretions were calculated. For analysis the group of newborns was divided into three according to gestational age: group A: less than 33 weeks; group B: 33-37 weeks; group C: greater than 37 weeks. The GFR was correlated to the conceptional age. Renal sodium losses exceeded alimentary supplementation in premature infants during the observation period. An additional supplementation of sodium seems therefore to be indicated early in life, as sodium balance is negative from the first day on. Individual investigations are necessary to evaluate the amount of sodium needed. 3-5 mMol/kg/day seem to be well tolerated and preventive for hyponatriaemia. Fluid administration during the first days should be calculated so that a weight loss of about 10% of body weight is achieved in premature infants in order to prevent cardiovascular and gastrointestinal complications. Because of a higher insensible water loss the amount of fluids administered per body weight should be higher in prematures than in matures.

Urinary protein analysis in the early detection of acute rejection episodes after renal transplantation in children

The purpose of the present longitudinal investigation was to assess the predictive value of urinary protein analysis in the early detection of rejection crisis after renal transplantation. Forty-one children were studied consecutively over a period of 6 months applying the following methods: creatinine clearance (Ccr); urinary total protein (UTP); and electrophoretic differentiation of urinary proteins according to their molecular size by microgradient-gel electrophoresis (MGGE) with a continuous concentration gradient of 4-40% of polyacrylamide. Protein fractions analyzed were albumin (69,000 d), low molecular weight proteins (LMW-proteins, less than 69,000 d), and high molecular weight proteins (HMW-proteins, greater than 69,000 d). No rejection was observed in 30 children (group A), a total of 18 rejection episodes occurred in 11 children (group B). UTP was significantly lower in group A as compared to group B (107 vs 376 mg/m2/24 h), but no differences in urinary protein pattern were observed between group A and group B prior to rejection. One to two days after rejection UTP increased to 938 mg/m2/24 h, and 3-7 days after rejection LMW-protein fraction increased from 9% to 23% with a corresponding decrease of albumin fraction from 71% to 56% of UTP. No qualitative changes were noted in respect to HMW-protein excretion. It is concluded that changes of UTP and urinary protein pattern occur during rejection episodes but are of no predictive value in detecting rejection before clinical symptoms appear.

[Pre- and postnatal diagnostic imaging of congenital urinary tract disorders]

The prenatal diagnosis of urinary tract obstruction was made in 10 neonates. These findings were confirmed postnatally by sonography, urography, voiding cystourethrography, and scintigraphy. There were 8 neonates with unilateral obstruction of the ureter, and 2 with urethral valves and reflux. Nephrectomy because of hydronephrosis was necessary in 2 instances. The prenatal diagnosis of a urinary tract obstruction is of great importance, because the neonate may be operated upon without delay. Thus the diseased kidney can be saved. Diuretic radionuclide urography is helpful in differentiating between dilated obstructed and dilated nonobstructed kidneys.

Stevens-Johnson syndrome during an immunosuppressive therapy with cyclophosphamide and prednisone

Corticosteroids are often recommended for the treatment of severe Stevens-Johnson syndrome. We report about a 12 years old boy, who developed this syndrome during an immunosuppressive therapy with prednisone and cyclophosphamide for a frequent relapsing, steroid-dependent nephrotic syndrome. Most of the commonly mentioned etiologic factors for erythema exudativum multiforme could be excluded. The usefulness of corticosteroids for the therapy seems to be doubtful.

Homozygous hypobetalipoproteinaemia and phenylketonuria

Two patients, aged 0.1 and 2 years, with homozygous hypobetalipoproteinaemia, one with PKU in addition are described. The clinical evaluation showed no neurologic abnormalities. Treatment with a fat-reduced, protein and carbohydrate-enriched diet was combined with vitamin A and E supplementation, according to the suggestions for classical abetalipoproteinaemia. In the patient with PKU the protein intake was increased by using a phenylalanine-free, amino acid mixture. Only by this, were normal growth and weight gain achieved.

Treatment of severe coagulation disturbances as a condition of improved prognosis in fulminant liver failure

A favourable outcome of fulminant liver failure by replacement treatment with antithrombin III, prothrombin concentrate, fresh frozen plasma, and plasminogen is reported. Haemostatic balance was maintained and no severe bleeding complications occurred during the 15 days of disturbed liver function.

Severe digoxin intoxication in a child treated by infusion of digoxin-specific Fab-antibody-fragments

Accidental digitalis ingestion in children is a rare, but potentially life-threatening emergency. We report the case of a 2 10/12-year-old boy with accidental ingestion of 6 mg beta-Acetyl-digoxin. Soon after admission, the boy developed sinus bradycardia, SA and AV-block, of increasing severity without circulatory impairment. As the serum digoxin level reached 21.7 ng/ml digoxin-specific Fab-antibody-fragments were used to bind free serum digoxin. Immediately after infusion, serum free digoxin was below the detection limit, whereas total digoxin peaked at 219 ng/ml 5 h thereafter. The arrhythmias did not subside totally, so that in addition, a transvenous pacemaker was placed, but never used. The antibody-infusion was well tolerated and the boy was discharged in good health.