A simple estimate of glomerular filtration rate in full-term infants during the first year of life

Single-dose gabapentin pharmacokinetics and safety in healthy infants and children

Gabapentin (Neurontin) is a gamma-aminobutyric acid analogue indicated in adults for adjunctive treatment of partial seizures with or without secondary generalization. Two studies were conducted to determine the single-dose pharmacokinetics of gabapentin in healthy subjects age 1 month to 12 years and to guide dose selection in safety and efficacy trials in pediatric patients. Forty-eight subjects were given single oral doses of gabapentin (10 mg/kg) while fasting. Enrollment was homogeneously distributed throughout the age range. Plasma samples were drawn predose and then serially for 24 hours postdose. Single doses of gabapentin were well tolerated by healthy pediatric subjects. Plots of pharmacokinetic parameters versus age suggested significant differences between younger (1 month to < 5 years) and older (> or =5 to 12 years) subjects. Mean area under the plasma concentration-time curve from zero to infinity (AUC(0-infinity)) was 25.6 microg x h/mL in younger subjects and 36.0 microg x h/mL in older subjects (p < 0.001). Corresponding mean peak plasma concentrations (Cmax) were 3.74 and 4.52 microg/ml (p < 0.05). Oral clearance (normalized for body weight) was 7.40 and 4.41 mL/min/kg in younger subjects and older subjects, respectively (p < 0.001). It was concluded that children between 1 month and < 5 years of age require approximately 30% higher daily doses of gabapentin than those > or =5 to 12 years of age.

Ultrasonographic features of nephrocalcinosis in preterm neonates

Nephrocalcinosis (NC) in preterm neonates has been reported frequently and small studies suggest an unfavourable effect on renal function. Data on ultrasonic features are limited and the reproducibility of ultrasonography (US) in detecting NC in preterm neonates is unknown. In this study, interobserver and intraobserver agreement of US was determined through videotape recordings of US examinations of preterm neonates. Furthermore, a prospective US study was performed in 215 preterm neonates (gestational age < 32 weeks) to evaluate ultrasonic characteristics, incidence, time course and effect on kidney length of NC. Patients were studied at 4 weeks after birth and at term. Patients with NC were followed for 2 years. NC was defined as bright reflections in the medulla or cortex seen in both transverse and longitudinal direction. The length of the kidneys was noted. The kappa value was 0.84 for intraobserver and 0.46 for interobserver agreement, whereas the overall agreement was 73%. NC was found in 50 of 150 (33%) patients at 4 weeks and in 83 of 201 patients (41%) at term. NC was localized mainly in the medulla. At 1 and 2 years, NC had persisted in 36% and 26%, respectively, of the patients with NC at term. Kidney length was comparable with normal values. In conclusion, US has a very good intraobserver agreement but a moderate interobserver agreement in detecting NC. Medullary NC is common among preterm neonates. During the first 2 years of life, the incidence decreases spontaneously and NC does not influence kidney length.

Reference ranges for plasma cystatin C and creatinine measurements in premature infants, neonates, and older children

AIM

To establish a reference range in the paediatric population for the new glomerular filtration rate (GFR) marker, cystatin C, and to compare it with that of creatinine.

METHODS

Cystatin C and creatinine were measured by particle enhanced nephelometric immunoassay (PENIA) and fixed interval Jaff¿e methods, respectively, in 291 children aged 1 day to 17 years, including 30 premature infants with gestational ages ranging from 24 to 36 weeks.

RESULTS

In the premature infants, concentrations of both cystatin C and creatinine were significantly raised compared with term infants, with cystatin C concentrations being between 1.10 and 2.06 mg/litre and creatinine between 32 and 135 micromol/litre. In premature infants, there was no significant relation between gestational age and cystatin C or creatinine concentration. Creatinine concentrations fell to a nadir at 4 months of age, rising gradually to adult values by about 15-17 years of age, in contrast to cystatin C, which fell to a mean concentration of 0.80 mg/litre by the 1st year of life, and remained constant throughout adulthood up to the age of 50 years. Neither analyte showed any influence of sex.

CONCLUSION

The measurement of cystatin C, rather than creatinine, is more practical for monitoring GFR changes in the paediatric population.

Linear growth after pediatric liver transplantation

To determine growth patterns in a large cohort of unselected children undergoing liver transplantation, the outcomes of 294 orthotopic liver transplantations performed in 221 children at The University of Chicago between October 1984 and October 1992 were retrospectively reviewed; 66% were alive at the time of this analysis. The mean age at transplantation was 4.1 +/- 5.0 years; 44% of the children were male and 16% of the transplants were from living-related donors. The mean height z score at the time of transplantation was -1.6 +/- 1.8, and 39% of children had height z scores of < -2.0 at transplantation. When children with growth retardation at the time of transplantation (height z scores of < -2. 0) were compared with children with more normal growth, there were no significant differences in gender or re-transplantation rates, although children with growth retardation at transplantation were significantly younger than those with more appropriate growth (2.8 +/- 4.1 years vs 4.7 +/- 5.1 years, P <.05). The height z score of all children with biliary atresia at the time of transplantation was -1.9 +/- 1.7 compared with -1.2 +/- 2.0 in those children with underlying diseases other than biliary atresia. Catch-up growth was seen in 37% to 47% of children at any given time point after transplantation. Children with evidence of catch-up growth (growth velocity z score >0) 2 years after transplantation were more likely to be first-time transplant recipients, had more growth retardation at the time of transplantation, and were receiving lower doses of prednisone at 2 years after transplantation. Younger children were most likely to demonstrate catch-up growth after transplantation. In summary, a large proportion of children have growth retardation at the time of liver transplantation. This growth retardation is inversely correlated with age. Before transplantation, children with biliary atresia grow less well than children with other forms of liver disease. Up to one half of children demonstrate catch-up growth after liver transplantation. Growth after transplantation is proportional to the degree of growth retardation at transplantation and inversely correlated to age at transplantation. Children with poor growth after transplantation are more likely to be receiving higher doses of corticosteroid.

Relationship between plasma creatinine concentration and glomerular filtration in preterm newborn infants

Fluid management and dosage regimens of drugs in preterm infants should be based on the glomerular filtration rate. The current methods to determine glomerular filtration rate are invasive, time-consuming, and expensive. In contrast, creatinine clearance can be easy obtained and quickly determined. The purpose of this study was to compare plasma creatinine on the third and seventh day of life in preterm newborn infants, to evaluate the influence of maternal creatinine, and to demonstrate creatinine clearance can be used as a reliable indicator of glomerular filtration rate. We developed a prospective study (1994) including 40 preterm newborns (gestational age < 37 weeks), average = 34 weeks; birth weight (average) = 1840 g, in the first week of life. Inclusion criteria consisted of: absence of renal and urinary tract anomalies; O2 saturation >/= 92%; adequate urine output (>1ml/kg/hr); normal blood pressure; absence of infections and no sympathomimetic amines in use. A blood sample was collected to determine plasma creatinine (enzymatic method) on the third and seventh day of life and creatinine clearance (CrCl) was obtained using the following equation: [formula: see text], k = 0.33 in preterm infant All plasma creatinine determinations showed normal values [third day: 0.78 mg/dl +/- 0.24 (mean +/- SD)and seventh day: 0.67 mg/dl +/- 0.31 - (p>0.05)]. Also all creatinine clearance at third and seventh day of life were normal [third day: 19.5 ml/min +/- 5.2 (mean +/- SD) and seventh day: 23.8 ml/min +/- 7.3 - (p>0,05)]. All preterm infants developed adequate renal function for their respective gestational age. In summary, our results indicate that, for clinical practice, the creatinine clearance, using newborn length, can be used to estimate glomerular filtration rate in preterm newborn infants.

[Estimation of glomerular filtration rate by the formula GFR = K x T/Pc]

BACKGROUND

Creatinine clearance is the most common method used to assess glomerular filtration rate (GFR). In children, GFR can also be estimated without urine collection, using the formula GFR (mL/min x 1.73 m2) = K x height [cm]/Pcr [mumol/L]), where Pcr represents the plasma creatinine concentration. K is usually calculated using creatinine clearance (Ccr) as an index of GFR. The aim of the present study was to evaluate the reliability of the formula, using the standard UV/P inulin clearance to calculate K.

METHODS

Clearance data obtained in 200 patients (1 month to 23 years) during the years 1988-1994 were used to calculate the factor K as a function of age. Forty-four additional patients were studied prospectively in conditions of either hydropenia or water diuresis in order to evaluate the possible variation of K as a function of urine flow rate.

RESULTS

When GFR was estimated by the standard inulin clearance, the calculated values of K was 39 (infants less than 6 months), 44 (1-2 years) and 47 (2-12 years). The correlation between the values of GFR, as estimated by the formula, and the values measured by the standard clearance of inulin was highly significant; the scatter of individual values was however substantial. When K was calculated using Ccr, the formula overestimated Cin at all urine flow rates. When calculated from Ccr, K varied as a function of urine flow rate (K = 50 at urine flow rates of 3.5 and K = 64 at urine flow rates of 8.5 mL/min x 1.73 m2). When calculated from Cin, in the same conditions, K remained constant with a value of 50.

CONCLUSIONS

The formula GFR = K x H/Pcr can be used to estimate GFR. The scatter of values precludes however the use of the formula to estimate GFR in pathophysiological studies. The formula should only be used when K is calculated from Cin, and the plasma creatinine concentration is measured in well defined conditions of hydration.

Serum creatinine is a poor marker of glomerular filtration rate in patients with spina bifida

Serum creatinine is used to estimate the glomerular filtration rate (GFR). The serum creatinine, however, may not accurately reflect the GFR in spina bifida patients, who often have decreased overall muscle mass resulting from spinal cord abnormalities. The relationship between the serum creatinine and GFR (obtained by [(125)I]iothalamate clearance) was examined in a population of spina bifida patients. Age-matched patients without spina bifida were used as controls. Results demonstrate that, for serum creatinines above 0.5 mg/dL, serum creatinine is a very poor predictor of GFR. Two patients with serum creatinines of 2.2 mg/dL are near end-stage renal disease with GFRs of 12.5 and 13 mL/minute per 1.73m2 and two patients were initiated on dialysis at the conclusion of the study. It is concluded that obtaining a GFR from a clearance study and not serum creatinine is the only reliable method to assess renal function in spina bifida patients once the serum creatinine is greater than 0.5 mg/dL.

Pharmacokinetics of once-daily dosing of gentamicin in neonates

In a prospective, randomized trial of once-daily versus twice-daily intravenous or intramuscular dosing with gentamicin, 11 neonates received 5.0 mg/kg once daily and 15 received 2.5 mg/kg twice daily for 2 ro 3 days. The once-daily intravenous dosing group and the twice-daily intravenous or intramuscular dosing group, respectively, had mean steady-state gentamicin peak concentrations of 10.7 versus 6.6 micrograms/ml (p < 0.05), 6-hour postdosing concentrations of 4.7 versus 2.8 micrograms/ml (p < 0.05), trough concentrations of 1.7 versus 1.7 micrograms/ml, elimination half-life of 8.8 versus 5.4 hours (p < 0.05), and volume of distribution at steady state of 0.67 versus 0.46 L/kg. No nephrotoxic effects were identified in any group. Once-daily gentamicin therapy with 5.0 mg/kg in neonates achieves peak serum levels that are more suitable for optimal bacterial killing than those which traditional regimens achieve. Similar trough levels suggest that even larger doses and longer dosing intervals may be ideal in term neonates.

Assessing fluid and electrolyte status in the newborn

Fluid and electrolyte assessment during the first week of life is complicated by rapid changes in fluid and electrolyte balance during the transition from fetal to neonatal life and by the newborn’s small size. A physiologic decrease in extracellular water volume, as well as a transient increase in serum potassium and transient decreases in plasma glucose and total plasma ionized calcium concentrations must be taken into account. In general, the more immature the newborn, the greater the changes that can be expected. The use of plasma creatinine as an indicator of glomerular filtration rate is limited because it is a function of maternal renal function at birth and because of non-steady-state conditions in the immediate postnatal period. Guidelines for monitoring schedules are provided on the basis of these physiologic considerations and the author’s experience. Method of blood sampling and time to separation of serum are important considerations in interpreting results. Minimization of sample volume is critical to minimize blood transfusion requirements. Clinicians should be aware of the analytical error associated with these measurements in their own institutions. Reference ranges are provided.

Height and weight in children with vesicoureteric reflux and renal scarring

Height standard deviation scores (HSDS) and weight-for-height index (WHI) at diagnosis were evaluated in 156 children aged 2 months to 10.8 years (mean 3.7 years) with vesicoureteric reflux (VUR) and normal creatinine clearance, and in 156 age- and sex-matched healthy controls. Forty-three patients had bilateral VUR with scintigraphic signs of renal scarring (B SCAR+), 25 had bilateral VUR without renal scarring (B SCAR-); 40 had unilateral VUR with (U SCAR+) and 48 unilateral VUR without (U SCAR-) renal scarring. B SCAR+ patients had an average HSDS of -0.5 +/- 1.4 (SD) which was significantly (P = 0.02) below that of controls (0.05 +/- 1 HSDS) and an average WHI of 100.6% +/- 16% which was significantly (P = 0.007) below that of controls (108% +/- 12%); 14% of B SCAR+ patients had a height below -2 HSDS. B SCAR-, U SCAR+, and U SCAR- patients had heights near to O HSDS which was not different from that of controls, as well as WHI between 104% and 107.9%, which was not different from that of controls. HSDS and WHI were significantly (P = 0.00001) correlated in patients but not in controls. B SCAR-, U SCAR+, and U SCAR- patients are similar to healthy controls in weight and in height growth and have, on average, some excess weight as do the latter. In contrast, B SCAR+ subjects have a significant decrease of the relative height and normal WHI.

Validity of random urines to quantitate proteinuria in children with human immunodeficiency virus nephropathy

Accurate assessment of proteinuria in pediatric patients infected with the human immunodeficiency virus (HIV) is limited by constraints imposed by timed urine collections and low creatinine excretion in very ill patients with low muscle mass. We therefore sought to validate the use of random urine specimens to quantitate total protein and creatinine excretion in a population of 236 HIV-positive children. A mathematical derivation for estimating urine volume (V) was constructed. The accuracy of the final calculation [V = 832 (kL/Ucr)BSA] (where k = constant, L body length, UCr urine creatinine and BSA body surface area) was tested by regression analysis comparing the calculated and measured volume of 31 urines from ambulatory HIV-negative patients. The correlation coefficient was highly significant (r = 0.77, P < or = 0.0001). The relationship was also applied to 23 timed urine specimens from HIV-positive patients with similar significance (r = 0.87, P < 0.0001). A regression analysis of measured proteinuria against the urine protein: creatinine ratio (Upr/Ucr) in these same urines from the HIV-positive patients yielded a significant relationship both in the linear (r = 0.95, y = 0.4x) and the logarithmic regression (r = 0.97, y = x + 0.4). These data support the use of random Upr/Ucr ratios to estimate daily proteinuria in HIV-infected pediatric patients despite low creatinine excretion rates. The previously accepted values continue to apply, with Upr/Ucr < or = 2.0 considered normal and > 2.0 representative of nephrotic proteinuria.

Evolution of upper urinary tract and renal function in patients with posterior urethral valves

From January 1972 to June 1993, 166 patients with posterior urethral valves (PUV) were treated in our surgical department, 59 with a milder form of PUV (upper urinary tract [UUT] complication rate 29%) and 107 with a severer form (UUT complication rate 96.3%). Only the latter group was studied for long-term (mean 9.3 years) evaluation of the UUT and renal function. A temporary vesicostomy was the primary treatment in 25 patients. Indications for temporary diversion were very young age and/or low birth weight, severe and bilateral UUT complications, and severe renal damage. All the other patients were treated by primary endoscopic valve fulguration. After removal of the lower urinary tract obstruction, vesicorenal reflux (VRR) resolved spontaneously or was ameliorated in 59.2% of the renal units. Spontaneous normalization or evident amelioration were found at long-term follow-up in nearly 70% of dilated, non-refluxing ureters. Ureteral reimplantation was performed on 41 of the 202 dilated or refluxing ureters (surgical rate 20.3%). The surgical failure rate requiring reoperation was 5% (2/41). The prerequisite for successful reimplantation was a large-capacity, stable, and compliant bladder. Ten nephroureterectomies were carried out for unilateral, massive VRR and renal dysplasia; 1 late nephrectomy was performed for arterial hypertension. The evolution of renal function showed statistically significant overall improvement, which was more evident in patients diagnosed and treated in the 1st month of life (P = 0.000) than in those treated between 1 and 12 months (P = 0.004) or after 1 year of age (P = 0.025). Renal function considerably improved in the vesicostomy group (P = 0.000). Thirteen patients (12.4%) are now either dead (2) or have end-stage renal disease (6) or chronic renal insufficiency evolving toward end-stage renal disease (5); 5 of these 13 were treated by vesicostomy in the first days or months of life, and at presentation the glomerular filtration rate (GFR) was less than 25 ml/min . 1.73 m(2). Determination of basic GFR and, even more, functional renal reserve is relevant in predicting the long-term evolution. In the author's opinion, vesicostomy is the procedure of choice in very ill newborns or infants. Aggressive management with early surgical reconstruction is rarely justified, because frequently UUT complications resolve spontaneously or clearly improve, and their surgical treatment has limited and very precise indications.

The prune-belly syndrome: current insights

The prune-belly syndrome comprises a constellation of well-established physical findings, yet the cause and management remain controversial. This review focuses on the current understanding of its pathogenesis and characterizes the fetal and neonatal diagnosis and management. Other associated anomalies are discussed to understand better the factors affecting treatment and prognosis as these patients grow into childhood and beyond.

Nonoliguric and oliguric acute renal failure in asphyxiated term neonates

The purpose of this study was to determine the prevalence and types of acute renal failure in asphyxiated full-term neonates and to evaluate the accuracy of an asphyxia morbidity score in predicting acute renal failure. Neonates admitted to one institution from 1990 through 1993 with a gestational age > or = 36 weeks and 5-min Apgar score < or = 6, without congenital malformations or sepsis, were studied retrospectively for acute renal failure in the 1st week of life. Acute renal failure was defined as serum creatinine > 1.5 mg/dl (133 mumol/l) with normal maternal renal function. Nonoliguric renal failure was defined as renal failure with urine output > 1 ml/kg per hour after the 1st day. An asphyxia morbidity scoring system was used to distinguish severe from moderate asphyxia. The score ranged from 0 to 9 and was based upon fetal heart rate, Apgar score at 5 min, and base deficit in the 1st h of life. The score for severe asphyxia was defined as 6-9 and for moderate asphyxia as 1-5. Sixty-six neonates fulfilled study criteria. Acute renal failure was present in 20 of 33 (61%) infants with severe asphyxia scores and 0 of 33 with moderate asphyxia scores (P < 0.0001). Acute renal failure was nonoliguric in 12 of 20 (60%), oliguric in 5 of 20 (25%) and anuric in 3 of 20 (15%). In conclusion 1) acute renal failure occurred in 61% of infants with severe asphyxia, 2) acute renal failure associated with severe asphyxia was predominantly nonoliguric and 3) an asphyxia morbidity score, which can be determined at 1 h of age, predicted acute renal failure in full-term infants with 100% sensitivity and 72% specificity.

Length/serum creatinine ratio does not predict measured creatinine clearance in critically ill children

OBJECTIVE

Information regarding renal function is important in critically ill children to adjust the dosage of drugs that are eliminated by the kidneys. Methods for estimating glomerular filtration rate (GFR) based on age and serum creatinine level have shown good agreement with measured creatinine clearance (CLCR) in children without critical illness but have not been examined in critically ill children.

METHODS

CLCR (24 hours) was measured (CLCR-measured) in 100 individuals (aged 5.6 years [range, 0.1 to 20.8 years]) admitted to a pediatric intensive care unit. Urine was collected by indwelling bladder catheters. Serum levels were determined. CLCR was calculated (CLCR-measured) according to the standard formula. GFR was estimated (CL-estimated) according to a published method, in which GFR is based on serum creatinine levels, patient length, and a constant that varies with the age and sex of the child. For each patient, the percentage difference between methods was calculated as the difference between the methods divided by the average obtained by the two methods and expressed as a percentage. Bias was calculated as the absolute value of the percentage difference.

RESULTS

CLCR-measured and CL-estimated were significantly correlated (CLCR-measured = 0.57 CL-estimated + 16.8; r = 0.68; p < 0.001). However, CL-estimated was greater than CLCR-measured in 84 patients. The difference ranged from -230 to +123 ml/min/1.73 m2 (mean -25.9 ml/min/1.73 m2 [95% confidence interval, -18.1 to 33.7 ml/min/1.73 m2]). The mean percentage difference between the methods was also large (-38.1% [95% confidence interval, -47.1% to 29.2%]) and ranged from -153.2% to 102.1%. The mean bias was 45.2% (95% confidence interval, 37.7% to 52.8%). In 36 of 100 patients the discrepancy between the two methods was greater than 50%. Adjusting for weight percentile, as a proxy for abnormal muscle mass, did not improve the model.

CONCLUSION

A method to estimate GFR in children that is based on age and sex, but not critical illness, does not correspond with measured 24-hour CLCR. Use of this method to adjust dosage of drugs eliminated by the kidney might result in significant overdosage in most critically ill children.

Improved neurological outcome in children with chronic renal disease from infancy

Progressive encephalopathy, developmental delay, microcephaly, electroencephalogram (EEG) and computed tomographic (CT) scan abnormalities have been reported in 80% of children with chronic renal failure (CRF) in infancy. Malnutrition, aluminium intoxication and psychosocial deprivation are proposed as causes. In 15 children with CRF from infancy we evaluated the effect of no aluminium salts and early vigorous nutritional and psychosocial support, in addition to the standard therapy, on neurological development. Six patients underwent dialysis (2 at birth) and 3 received transplants. None of our patients were given aluminium therapy. The nutritional status of the patients in the first 2 years of life was assessed with the waterlow classification. At the end of the follow-up period (mean 50 months range 14-148 months), patients underwent neurodevelopmental assessment, head CT scan, EEG, nerve conduction velocity (NCV) and auditory brain stem evoked response (ABER). None of our patients developed progressive encephalopathy or recurrent seizures. All have a normal neurological examination apart from hypotonia. Microcephaly was present in 5 patients. There was a good correlation between malnutrition in the first 2 years of life and microcephaly. Developmental delay was present in 3 patients; all 3 were microcephalic. There was evidence of brain atrophy on CT scan in only 3 patients. EEG was abnormal in 6 patients, but only severe in 1 patient. Only 1 patient had diminished NCV; all patients had a normal ABER. We conclude that a policy of no oral aluminium therapy and early nutritional support leads to better neurological outcome in children with CRF from infancy.

Autosomal recessive polycystic kidney disease in 15 Arab children

The study includes 15 children (8 males, 7 females) with autosomal recessive polycystic kidney disease (ARPKD) whose ages at diagnosis ranged from 2 days to 7 years (median 10 months). Eleven (73.3%) patients were hypertensive on admission and 1 developed hypertension 4 months later; 5 patients became normotensive after receiving treatment for 18-36 months (mean 23.2 months). Patients were followed for a period of 1-48 months (mean 20.9 months). Glomerular filtration rate remained normal in 7 patients, improved in 4 and deteriorated in 1. Two patients died soon after diagnosis and 1 was lost to follow-up and is assumed dead. Of the 4 patients less than 6 months old at the time of diagnosis, only 1 is alive compared with 10 of 11 presenting after 6 months of age. The cumulative chance of survival from the time of diagnosis was 85% at 3 months and 77% at 6 months. The study highlights the reversible nature of hypertension in ARPKD. Survival is better in patients older than 6 months at the time of diagnosis and those surviving 6 months follow-up.

Intrathrombic urokinase reverses neonatal renal artery thrombosis

A term infant with aortic and renal artery thrombosis is described, in whom the right kidney experienced complete ischemia for 5 days. A continuous intrathrombic urokinase infusion induced complete clot lysis and reperfusion of the right kidney. Follow-up studies of renal function and renal growth have been normal. This is the first report to describe complete pharmacological salvage of a neonatal kidney after prolonged warm ischemia. This case underscores both the ability of the neonatal kidney to recover from prolonged ischemia and the need to effect thrombolysis before irreversible renal injury occurs. The intrathrombic use of fibrinolytic agents in similarly affected infants warrants consideration and further study.

Serial measurements of GFR in infants using the continuous iothalamate infusion technique. Southwest Pediatric Nephrology Study Group (SPNSG)

We undertook a preliminary study to determine if a clinical trial was feasible that would compare the effect of a low protein vs a control formula on GFR and growth in infants with congenital renal insufficiency (CIo < 55 ml/min/1.73 m2). In this report from the Infant Diet Protein Study, we describe validation of a method using the plasma clearance of iothalamate (CIo) as an estimate of glomerular filtration rate (GFR) and results of the preliminary study relating to renal function. The plasma CIo method was validated as an accurate estimate of GFR by showing it to be the same as the plasma clearance of inulin (CIn). In the preliminary study infants who qualified for the study were randomly assigned to a low protein or control formula and were followed from 8 to 18 months of age. CIo was measured at 8, 14 and 18 months of age in 21 of the infants and at 8 and 18 months of age in all twenty four infants that entered the study. Average absolute GFR in the 24 infants increased in the 10 month period from 5.3 +/- 2.7 to 7.6 +/- 4.5 ml/min. The percent increase in GFR was no different in infants whose GFR at 8 months of age was severely reduced from those whose GFR was only moderately reduced. When adjusted for age and body size, GFR did not change. Change in mean CIo or serum creatinine (SCr) from 8 to 18 months of age between the infants in each diet groups was not different. We conclude that a clinical trial enrolling more infants and extending the study period is necessary to evaluate dietary protein effect.

Creatinine for estimation of glomerular filtration rate

The aim of this study was to evaluate the plasma creatinine concentration (PCr) and creatinine clearance (CCr) for estimation of glomerular filtration rate (GFR). Inulin clearance (Cin) was used as the reference standard for GFR. Thirty-nine concurrent Cin and CCr studies provided data for comparing Cin with the measured CCr and with the calculated CCr (calc-CCr). (Calc-CCr = k.L/PCr, where L = height in centimeters and k is the proportionality constant.) Thirty-one children 5.3-20.8 years of age, with Cin ranging from 2.8 to 138.8 ml/min per 1.73 m2, participated in these studies at The Children's Mercy Hospital. The measured CCr was 16.7 +/- 10.3 ml/min per 1.73 m2 (P < 0.001) greater than the Cin, and the calc-CCr overestimated Cin by a mean of 31.6 +/- 20.8 ml/min per 1.73 m2 (P < 0.001). Although there is good correlation between Cin and CCr (r = 0.96), and Cin and calc-CCr (r = 0.90), the 95% confidence intervals are quite broad. Hence, the CCr and the calc-CCr, derived using Schwartz values for k, consistently overestimate GFR. However, if the k value in the equation GFR = k.L/PCr is derived from k = Cin/L, rather than from k = CCr.PCr/L, a more accurate estimate of GFR may be obtained.

Glomerular abnormalities in children undergoing orthotopic liver transplantation

A prospective study of renal function was undertaken on an unselected group of 8 children with chronic progressive liver disease on whom a renal biopsy was performed subsequently at the time of orthotopic liver transplantation. Two patients had abnormal urinalyses and 2 elevated urinary albumin/creatinine ratios. The remainder had no clinical evidence of renal dysfunction. All had normal serum creatinine concentrations. Glomerular abnormalities were present in all renal biopsies and were of two types: hepatic glomerulosclerosis (n = 5) and minor glomerular abnormalities (n = 3). IgM immunofluorescence was present in all biopsies and IgA in 6. Elevated serum immunoglobulin levels were observed in all patients, with IgM elevation in 6, IgA in 4 and IgG in 6. C3 and/or C4 were reduced in 5 patients and increased circulating immune complexes containing IgM were noted in 4. The clinical significance of these cirrhosis-associated glomerular abnormalities can only be established by long-term follow-up studies after orthotopic liver transplantation.

Safety and pharmacokinetics of fluconazole in children with neoplastic diseases

To evaluate the safety, tolerance, and pharmacokinetics of fluconazole in children with neoplastic diseases, we studied fluconazole in 26 children, aged 5 to 15 years, with normal renal function who were receiving treatment for cancer. The patients received fluconazole, 2, 4, or 8 mg/kg per day for 7 days intravenously for a 2-hour period. Patients had no nausea or vomiting related to fluconazole; three patients had an asymptomatic rise in hepatic aminotransferase values after four to six doses (one patient at 2 mg/kg per day and two patients at 8 mg/kg per day), which returned to normal within 2 weeks after discontinuation of the drug. Fluconazole showed linear first-order kinetics over the dosage range tested and during multiple dosing. After the first dose, mean clearance was 22.8 +/- 2.3 ml/min, volume of distribution 0.87 +/- 0.06 L/kg, and terminal elimination half-life 16.8 +/- 1.1 hours. Similarly, after the last dose, clearance was 19.4 +/- 1.3 ml/min, volume of distribution 0.84 +/- 0.04 L/kg, and terminal elimination half-life 18.1 +/- 1.2 hours. Patients receiving their first fluconazole dose of 8 mg/kg achieved peak serum levels of 9.5 +/- 0.4 microgram/ml and trough levels of 2.7 +/- 0.5 microgram/ml 24 hours later, and an area under the serum concentration-time curve from time zero to infinity of 186 +/- 16 micrograms.hr per milliliter. Renal clearance of fluconazole was 65% +/- 5% of total clearance and demonstrated the predominantly renal excretion of this drug. We suggest that the shorter serum half-life and the higher frequency of aminotransferase elevations in comparison with those of adults warrant careful investigation of fluconazole in controlled clinical trials.

Gentamicin interval in newborn infants as determined by renal function and postconceptional age

We evaluated the relationship between gentamicin pharmacokinetics and glomerular filtration rate in newborn infants to estimate the appropriate interval of administration in neonates with renal insufficiency. Gentamicin half-life (Gt1/2) could be predicted from plasma creatinine concentration (PCr) (r = 0.78); the prediction was minimally but significantly increased (r = 0.81) by adding post-conceptional age to a multiple regression analysis. Infants with a postconceptional age of 29 weeks or more and a PCr of 1 mg/dl or more had significantly greater through and peak gentamicin levels than those with a PCr less than 1 mg/dl. If gentamicin is indicated in a patient with renal insufficiency, the interval of administration should be 2-3 Gt1/2, which can be estimated from PCr (Gt1/2 = 2.0 + 7.7 PCr). The interval can then be adjusted according to peak and trough gentamicin levels.

Serum alpha 1-microglobulin and beta 2-microglobulin for the estimation of fetal glomerular renal function

As proteins cannot cross the placenta levels of the microproteins alpha 1-microglobulin (alpha 1MG) and beta 2-microglobulin (beta 2 MG) can be used to assess fetal glomerular renal function. alpha 1MG, beta 2MG and creatinine were routinely determined in cord and maternal blood of 133 newborns [gestational age (GA) 25-42 weeks]. Twenty-nine patients with suspected impaired maternal or fetal renal function were studied separately and two fetuses were studied in utero. The mean fetal beta 2MG concentration fell from 3.87 +/- 0.56 mg/l in the 25-31 weeks GA group to 2.60 +/- 0.50 mg/l in the mature newborn group. alpha 1MG concentration fell from 3.10 +/- 0.51 to 2.25 +/- 0.49 mg/dl. In contrast, the mean maternal beta 1MG concentration rose from 1.73 +/- 0.69 mg/l in the 25-31 weeks GA group to a mean of 1.83 +/- 0.48 mg/l in the mature newborn group; alpha 1MG rose from 3.96 +/- 0.58 to 4.33 +/- 1.6 mg/dl. Maternal and fetal creatinine levels were identical. Fetal microprotein levels fall during intra-uterine development as glomerular filtration rate (GFR) rises. There is no correlation between cord blood and maternal alpha 1MG or beta 2MG concentrations. In 13 children with urological anomalies only 1 had elevated microprotein levels and he later developed renal insufficiency. Determination of microprotein levels in fetal serum can be used to detect severe renal function disturbances and to estimate GFR independently of maternal renal function.

A comparison of two common clinical methods with high-pressure liquid chromatography for the measurement of creatinine concentrations in neonates

The accurate measurement of low serum creatinine levels is necessary for estimating clinically useful creatinine clearances in the pediatric population. This study compares two routine clinical methods: the kinetic Jaffé with the newer Kodak enzymatic method against our reference method, high-pressure liquid chromatography, for the measurement of serum and urine creatinine levels in neonates. One hundred and twenty-five serum and 59 urine creatinines and 56 absolute creatinine clearances were measured in neonates ranging from 23 to 46 weeks (mean 32 weeks) post-conceptional age and weighing 480-4398 g (mean 1650 g). Urine creatinine levels, and serum creatinine levels greater than 0.8 mg/dl were equivalent for both clinical methods. However, the enzymatic method was much more accurate (P less than 0.001) than the kinetic Jaffé method for serum creatinine measurements of less than or equal to 0.8 mg/dl. We conclude that the enzymatic methodology is a better clinical choice for the accurate measurement of serum creatinine levels when using these values for the determination of neonatal renal function.

Forced hydration prior to renography in children with hydronephrosis. An evaluation

We have developed a method of diuretic renography for the assessment of upper urinary tract obstruction in children. A maximal diuresis under standardised conditions is obtained by forced intravenous hydration over a 2-h period prior to renography. We evaluated the predictive value of this method for the clinical and functional outcome in 73 children with apparent unilateral pelviureteric junction obstruction. The predictive value of a non-obstructive pattern was 94%, while the predictive value of an obstructive pattern could not be assessed accurately because the patients concerned subsequently underwent operation. The method is safe and reliable and offers advantages over conventional diuretic renography.

The management of posterior urethral valves by initial vesicostomy and delayed valve ablation

We managed 32 neonates and infants with temporary vesicostomy and delayed valve ablation. The criterion on which successful management was gauged was estimated creatinine clearance. Renal failure or death occurred in 30% of the patients and 7% required transplantation. There was no apparent difference between our patients managed initially with vesicostomy and other series managed initially with valve ablation in preventing the complications of posterior urethral valves.

Treatment of steroid-resistant focal segmental glomerulosclerosis with pulse methylprednisolone and alkylating agents

In children, steroid-resistant nephrotic syndrome due to focal segmental glomerulosclerosis (FSGS) is frequently a progressive condition resulting in end-stage renal disease. There have been no reports of effective treatment for this condition. For the past several years, the Pediatric Nephrology services at the University of California, San Diego and Stanford University Schools of Medicine have treated these patients with a protocol involving infusions of high doses of methylprednisolone, often in combination with oral alkylating agents. Twenty-three children have been treated in this manner with a follow-up of 46 +/- 5 months. Twelve of these children are in complete remission. Six have minimal to moderate proteinuria. Four children remain nephrotic. Each of these children has a normal glomerular filtration rate. One child developed chronic renal failure and subsequently died while on dialysis. These results appear significantly better than previous series of children with FSGS. A controlled, multi-center trial of this protocol has been proposed.

Beckwith-Wiedemann syndrome. Renal pathology at 4 months of age

This report describes a child with nephromegaly and Beckwith-Wiedemann syndrome. The type and extent of the renal involvement could not be determined by imaging techniques. A pathologic examination of the renal biopsy tissue in this case demonstrated diffuse interstitial dysplasia. This is the first early pathologic description of the renal pathologic process in a living child with Beckwith-Wiedemann syndrome. The renal pathology indicates that children with this syndrome who survive other complications of the disorder have the potential for progressive renal disease.

Feeding disorders and gastroesophageal reflux in infants with chronic renal failure

Twenty-two infants (mean age 7.5 months) with chronic renal failure (CRF) were studied for their nutrition, growth, and upper gastrointestinal function. Most infants had a history of poor caloric intake and 7 had received supplemental feeding (SF) prior to the investigation. All infants were undergrown, underweight, and malnourished. The infants were characterized as having only a fair interest in food, refusing feedings, and vomiting excessively. Sixteen of 22 infants (73%) had significant gastroesophageal (GE) reflux demonstrated by 24-h esophageal pH monitoring. Gastroesophageal scintiscans were less sensitive and specific in detecting the reflux. Infants with GE reflux were significantly younger and more often required SF than those without GE reflux. There were no significant differences in the degree of renal failure, growth failure, caloric intake, protein intake, or nutritional status between the infants with and without GE reflux. From these studies we conclude that GE reflux should be considered as one of the factors contributing to the feeding problems of infants with CRF.

Digoxin clearance and serum beta-2-microglobulin in neonates

To find reliable indicators of digoxin clearance (CLdig) in the neonatal period, we investigated the linear correlation of CLdig and the reciprocal of CLdig (1/CLdig) with serum beta 2-microglobulin (S beta 2-MG), serum creatinine, blood urea nitrogen, age, and weight on 25 occasions in 21 neonates with congenital heart disease. The S beta 2-MG value showed a significantly closer correlation to 1/CLdig (r = 0.84, p less than 0.0001) than to the other values. The regression equation was (1/CLdig) = 0.15 X (s beta 2-MG) + 0.08. Creatinine and blood urea nitrogen values correlated less closely with 1/CLdig (r = 0.67 and 0.71, respectively). Age and weight had no significant linear correlation with CLdig and 1/CLdig. Determination of s beta 2-MG values allowed an estimate of CLdig by means of the regression equation between s beta 2-MG and 1/CLdig, and permitted a prediction of the required maintenance dose of digoxin. We conclude that s beta 2-MG is a good indicator of CLdig in neonates, and that the determination of s beta 2-MG values may facilitate the advance individualization of digoxin therapy in the neonatal period.

Favorable outcome of neonatal aortic thrombosis and renovascular hypertension

Fifteen children with renovascular hypertension as a result of aortic thrombosis were followed for a mean of 26 months (range 5 to 58 months) to determine outcome. As neonates, all patients had hypertension and elevated plasma renin activity. Of 11 patients studied with radionuclide renography and scintigraphy, 10 had abnormal renal blood flow; three had complete absence of unilateral perfusion. On follow-up examination all children were normotensive; five children ages 5 to 24 months required antihypertensive medication. Of 15 children, 14 had normal statural growth; all had normal serum creatinine, plasma renin activity, and calculated glomerular filtration rate values. Patients with complete absence of renal perfusion unilaterally remained functionally anephric; children with less severe perfusion deficits had improved perfusion as shown by radionuclide renography and scintigraphy. We believe that many patients with aortic thrombosis and renovascular hypertension who have had aggressive antihypertensive therapy in the neonatal period will have good renal function and increased perfusion to the affected kidney 2 years later.

Disturbances of brain maturation and neurodevelopment during chronic renal failure in infancy

Fifteen infants with moderate to severe congenital renal disease were prospectively studied by serial renal, neurodevelopmental, neurophysiologic, and anthropometric assessments. The observation period ranged from 3 to 25 months (mean = 10.9). Eight patients maintained a Mental Development Index (MDI) above the 16th percentile (greater than -1 SD) and comprised group 1. Of the remaining seven patients (group 2), three had an MDI less than 16th percentile when first studied and four had serial decreases of the MDI to less than 16th percentile. Although motor development was more delayed in group 2 at study entry, there were no significant changes of motor performance levels for either group during the study period. Group 2 patients had smaller length (p less than 0.05) and head circumference (p less than 0.05) standard deviation scores in comparison with group 1, and they had higher serum creatinine values (mean = 3.8 vs 1.3 mg/dl, respectively; p less than 0.01). By spectral electroencephalography, the expected progressive increase of the frequency of cerebral cortical background activity with age was demonstrated in group 1 but was not seen in group 2 (multivariate analysis of variance p less than 0.03). This increase of faster-frequency activity was primarily manifested in the left cerebral hemisphere of group 1 patients (p less than 0.01), a finding that was also absent in group 2. The frequent occurrence of neurodevelopmental abnormalities in infants with renal failure is possibly a consequence of impaired dominant hemispheric maturation in the first several years of life, which is clinically manifested as deterioration of cognitive function.

Estimation of glomerular filtration rate in anorectic adolescents

Severe malnutrition has been associated with a decrease in fat and lean body mass, as well as in renal function. This study was designed to evaluate the estimation of glomerular filtration rate (GFR, ml/min per 1.73 m2) in malnourished teenagers, by using the formula GFR = kL/Pcr (where L is body height, Pcr is plasma creatinine concentration and k is a proportionality constant relating muscle mass to body size that has been found to equal 0.7 in adolescent boys and 0.55 in girls). Body composition was estimated using anthropometric measurements and urinary creatinine excretion (UcrV). Malnourished female patients showed depletion of fat and muscle, whereas males had primarily decreased muscle mass. There was a good correlation (r = 0.74) between anthropometric [arm muscle volume (AMV)] and chemical UcrV estimates of muscle mass. However, our previously validated estimate of GFR did not give reliable results in this group of malnourished teenagers, probably because their muscle mass was so greatly altered by the severity of malnutrition. Therefore, we used anthropometric measurements and Pcr, to estimate GFR by multiple linear regression. The best prediction was obtained by using AMV/Pcr and the observed/expected (for age, height and sex) weight ratio (WR): GFR (ml/min) = 0.06 AMV/Pcr + 131 WR - 79, r = 0.82, n = 13. We confirm that malnutrition in adolescents is associated with decreased GFR and conclude that the resulting variability in body composition limits the possibility of estimating GFR from Pcr and height.(ABSTRACT TRUNCATED AT 250 WORDS)

The extraction factor: an estimate of single kidney function in children during routine radionuclide renography with 99mtechnetium diethylenetriaminepentaacetic acid

An estimate of absolute renal function in children is described using the initial extraction of 99mtechnetium diethylenetriaminepentaacetic acid. The extraction factor correlates well with the glomerular filtration rate as determined by the clearance from the blood of 99mtechnetium diethylenetriaminepentaacetic acid with a correlation coefficient of 0.92. The normal mean extraction factor in the newborn is 1.5 per cent by each kidney, which increases to 2.5 per cent in the first year of life. The method is simple to perform and it is reproducible provided care is taken. We recommend that this procedure be included as part of the routine renal scan in children.

Evidence that calcitonin plays a role in the postnatal increase of serum 1 alpha,25-dihydroxyvitamin D

To investigate the changes in the 1 alpha,25-dihydroxyvitamin D [1,25(OH)2D] level and the role of parathyroid hormone (PTH) and calcitonin (CT) during the early neonatal periods, we measured 1,25(OH)2D, 25-hydroxyvitamin D [25(OH)D], PTH specific for mid-regions (mPTH) and urinary cAMP (UcAMP) to evaluate the renal tubular responsiveness to intrinsic PTH and CT, as well as serum Ca and P in 28 mothers at term delivery and in their babies at birth and 5 days of age. Cord serum 1,25(OH)2D levels were low (28.8 +/- 9.2 pg/ml, mean +/- SD), while maternal serum 1,25(OH)2D levels were high (62.2 +/- 22.6 pg/ml). The low 1,25(OH)2D value increased 2.5 times (62.2 +/- 22.6 pg/ml) in 5-day-old infants, reaching a high normal adult value, concomitant with the increases in mPTH and urinary cAMP/creatinine ratio (UcAMP/Cr). The correlations between 1,25(OH)2D and UcAMP/Cr, and 1,25(OH)2D and mPTH in all paired samples of babies at birth and at 5 days of age were r = 0.456, n = 50, P less than 0.01 and r = 0.341, n = 50, P less than 0.05, respectively. These data suggest that the parathyroid activation after birth is a major factor in the rapid 1,25(OH)2D increment at that time. CT levels were high in all paired samples and in 5-day-old infants. CT vs 1,25(OH)2D showed a significant correlation (r = 0.473, P less than 0.05, n = 24) as well as the relative increase of 1,25(OH)2D (delta pg/ml) after birth vs CT at age 5 days (r = 0.537, P less than 0.01, n = 24).(ABSTRACT TRUNCATED AT 250 WORDS)

Polycystic kidney disease in the first year of life

To determine the frequency of autosomal recessive and autosomal dominant polycystic kidney disease (PKD) in infants and to compare the rate of progression of these conditions, we conducted a retrospective survey of 48 patients who were seen with PKD before 1 year of age and who survived the first month of age. Seventeen patients had recessive PKD; six had dominant PKD. Eighteen patients had insufficient data to categorize the type of PKD with certainty. Seven patients were classified as "other"; three had glomerulocystic disease and the remainder had multiple malformation syndromes or tuberous sclerosis. Renal ultrasonography and excretory urography accurately detected 15 of 17 patients with recessive PKD, but only one patient with dominant PKD was correctly diagnosed by excretory urography. The majority of patients in all groups required antihypertensive therapy. The 17 children with recessive PKD have been followed up for 6.1 +/- 4.3 (SD) years. Eight patients are doing well. Two patients have died; five others have required treatment for renal failure. Only one patient has an estimated glomerular filtration rate within the normal range after 6 years of age. Long-term evaluation of most of the patients with dominant PKD is not yet available; however, by age 42 months one patient has required dialysis. To provide optimum genetic counseling and accurate diagnosis for patients with PKD, a combination of careful family evaluation, radiography, and liver or kidney biopsy is required. The outcome of patients who survive the neonatal period appears not to be so grim as previously feared, underscoring the importance of aggressive supportive care and the need for physician and family education.

Pharmacokinetics of acyclovir suspension in infants and children

Eighteen children from 3 weeks to 6.9 years of age were given an oral acyclovir suspension for herpes simplex or varicella-zoster virus infections. Thirteen patients who were 6 months to 6.9 years old received 600 mg/m2 per dose, and three infants and two children less than 2 years old were given 300 mg/m2 per dose. The drug was given four times a day, except to one infant who was treated with three doses a day. Among the 13 children who received the 600-mg/m2 dose, the maximum concentration in plasma (Cmax) was 0.99 +/- 0.38 microgram/ml (mean +/- standard deviation), the time to maximum concentration (Tmax) was 3.0 +/- 0.86 h, the area under the curve (AUC) was 5.56 +/- 2.17 micrograms.h/ml, and the elimination half-life (t1/2) was 2.59 +/- 0.78 h. The three infants less than 2 months of age who received the 300-mg/m2 dose had a Cmax of 1.88 +/- 1.11 micrograms/ml, a Tmax of 4.10 +/- 0.48 h, an AUC of 6.54 +/- 4.32 micrograms.h/ml, and a t1/2 of 3.26 +/- 0.33 h. The acyclovir suspension was well tolerated by young children. No adverse effects requiring discontinuation of the drug occurred.

Postnatal development of renal function during the first year of life

Several aspects of renal function vary considerably during the 1st year of life and differ markedly from the equivalent values in the adult. Glomerular filtration rate (GFR) increases little, prior to the time an infant reaches a conceptional age of 34 weeks, the point in renal development from which the absolute GFR (ml/min) increases gradually to mature values when linear growth is completed during adolescence. GFR corrected for body size is not comparable with adult normal values until after 12 months of age; therefore, whether GFR is estimated from Scr or measured by timed urine collection, there is no easily recalled range of normal values for infants. One must know the changes in the renal function of normal infants that take place following birth during the 1st year of life. Despite several attempts to do so, renal function during the 1st year of life cannot be assessed from urine flow rate. A urine flow rate of less than 1 ml/kg per hour may be normal and appropriate and may not be harmful either to preterm or full-term infants with normal GFR. Impaired concentrating ability of the neonatal kidney is probably of no clinical significance in all but the most extreme circumstances and is not a major factor in an infant becoming dehydrated, developing hypernatremia or being at greater risk of acute renal injury. Acid-base status in infants must be interpreted appropriately to know when alkali therapy should be introduced to avoid growth failure secondary to true metabolic acidosis. When plasma renin activity is measured in the infant with renal failure of hypertension, one must compare the result with the normal range of values related to postnatal age of normal infants.

The use of plasma creatinine concentration for estimating glomerular filtration rate in infants, children, and adolescents

The formula GFR = kL/Pcr can be used to estimate GFR in infants, children, and adolescents who have grossly normal body habitus and are in steady-state condition. GFR is expressed in ml/min per 1.73 m2 BSA, L represents body length in cm, Pcr represents plasma creatinine concentration in mg per dl and k is a constant of proportionality that reflects the relationship between urinary creatinine excretion and units of body size. The value of k varies as a function of age and sex being 0.33 in preterm infants, 0.45 in full-term infants, 0.55 in children and adolescent girls, and 0.70 in adolescent boys. The advantages of rapid determination, reasonable accuracy, and the avoidance of urine collection justify the use of this formula in pediatric patients.

Nutritional management of children with chronic renal failure. Summary of the task force on nutritional management of children with chronic renal failure

Current information on the adaptations to progressive loss of renal function is presented. The assessment of renal function in infants and children using serum creatinine concentration and its derivatives is considered as are various methods for assessment of growth. Children with creatinine clearances less than 50% of normal, who do not have uremic symptoms (and who are not on dialysis), should be ingesting diets providing close to 100% of the RDA for calories with 8% of the calories as protein. Recommendations for nutritional management of children on chronic peritoneal dialysis are also presented.

Statural growth of children with chronic renal failure on conservative treatment

Statural growth was studied in 20 prepubertal children with chronic renal failure on conservative treatment followed-up 1.1 to 8.9 years (average 3.9). Five children reached end-stage renal failure during the follow-up period and underwent dialysis or transplantation. Most patients grew at a normal rate. During the observation period only 1 out of 20 children lost more than 0.5 height standard deviation score whereas 9 gained 0.5 to 3.1. A growth velocity above the 97th percentile for at least 1 year was observed in 6 patients. A normal growth rate and even catch-up growth is possible in children with chronic renal failure regardless of the degree of reduction of glomerular function.

Acute hepatic failure after open-heart surgery in children

Acute hepatic failure (AHF) combined with acute renal failure (ARF) is a well-known complication of open-heart surgery in adults. The occurrence of this complication in two children after open-heart surgery for correction of congenital heart disease is reported. Hypotension occurred during the operation and was treated by catecholamine vasopressors. AHF set in during the postoperative course; it was manifested by impaired consciousness, hypoglycemia, hyperbilirubinemia, hyperammonemia, elevated liver enzymes and prolongation of the prothrombin time with failure of hemostasis. ARF also developed in both children. One of the patients survived the acute episode of hepatic failure. The importance of early diagnosis, routine close monitoring, and appropriate selection of vasopressors is emphasized.