Acute Renal Failure In Neonate Research Articles

Acute renal failure in neonatal sepsis

To evaluate the occurrence of acute renal failure (ARF) and the factors associated with it in cases of neonatal sepsis. The case control study was conducted in the referral neonatal intensive care unit of a tertiary teaching hospital. 200 out born neonates with sepsis admitted to the nursery from January to July 2003 were evaluated for presence of ARF (cases) or not (controls). Sepsis was diagnosed on the basis of either a positive sepsis screen (immature: total (I:T) neutrophil ratio > 0.2, micro-ESR > age in days + 2 mm or> 15 mm, CRP> 6 mg/dl, TLC< 5000 cells/mm3; 2 or more positive) or a positive blood culture in symptomatic neonates. ARF was defined as blood urea nitrogen (BUN)> 20mg/dl on two separate occasions at least 24 hours apart. Oliguria was defined as urine output < 1 ml/Kg/hr. 52 out of 200 (26%) neonates with sepsis had ARF; only 15% of ARF was oliguric. The mean gestation of neonates with ARF was similar to those without ARF (36.1+/-4.1 wks vs. 36.6+/-3.5 wk; p = 0.41). A significantly higher number of babies with ARF weighed less than 2500 gm as compared to those without ARF (86.5% vs 67.6%; p = 0.008). The association of meningitis, disseminated intravascular coagulation (DIC) and shock was also significantly higher in neonates with ARF (46.8% vs 26.2%, p = 0.01; 65.4% vs 20.3%, p < 0.001; 71.2% vs 27.0%, p < 0.001 respectively). Mortality in neonates who developed ARF was significantly higher (70.2% vs 25%, p < 0.001). Factors including gestational age, weight, onset of sepsis, culture positivity, associated meningitis, asphyxia, shock, prior administration of nephrotoxic drugs were subjected to univariate analysis for prediction of fatality in neonates with sepsis and ARF; only shock was found to be a significant predictor of fatality (p< 0.001). ARF had recovered in 22 out of 49 neonates in whom data was available; three patients had left against medical advice. The mean duration of recovery in these 22 neonates was 5.5 days (range 1-14 days). Presence of co-existing morbidities (perinatal asphyxia/congestive heart failure (CHF)/ necrotising enterocolitis (NEC)) or nephrotoxic drugs did not alter the frequency of recovery of ARF in septic neonates (45.5% vs 44.4%,p = 0.944; 41% vs 52%, p = 0.308 respectively). Renal failure occurred in 26% neonates with sepsis. Although ARF in neonates has been reported to be predominantly oliguric, it was observed that ARF secondary to neonatal sepsis was predominantly non oliguric. Low birth weight was an important risk factor for the development of ARF. The mortality being three times higher in neonates with ARF demands a greater awareness of this entity among practitioners and better management of this condition.

Acute Renal Failure Management in the Neonate

After completing this article, readers should be able to: 1. Define the types and delineate the causes of acute renal failure (ARF) in neonates. 2. Describe the laboratory tests and imaging studies used to diagnose ARF. 3. Explain the roles of fluid balance, diuretics, dopamine, and nutrition in the management of neonatal ARF. 4. Describe the approaches to treating hyponatremia, hyperkalemia, calcium-phosphorus perturbations, acidosis, and hypertension in ARF. 5. Review the outcome and prognosis for ARF in neonates. Acute renal failure (ARF) is a very common problem in the neonatal intensive care unit. The newborn kidney has a very low glomerular filtration rate (GFR) that is maintained by a delicate balance between vasoconstrictor and vasodilatory forces. (1) Although sufficient for growth and development under normal conditions, the low GFR of the newborn kidney limits postnatal renal functional adaptation to endogenous and exogenous stresses. (2) This limited response predisposes the newborn to the development of ARF and is even more pronounced in the low birthweight infant (ie, <2,500 g due to preterm birth or intrauterine growth restriction). (3) Given this predisposition, early identification of ARF in the neonate is essential to preserving renal function. The true incidence of neonatal ARF is difficult to ascertain, but studies have reported that 8% to 24% of newborns admitted to the neonatal intensive care unit present with ARF. These percentages are likely an underestimation because many cases of nonoliguric neonatal ARF, which occurs commonly in sick neonates, are excluded. (1) ARF is defined as a sudden decrease in GFR that results in the progressive retention of creatinine and nitrogenous waste products and the inability to regulate fluid and electrolyte homeostasis. The definition of ARF in neonates is less precise because the serum creatinine shortly after birth is a reflection of maternal renal function, usually less than 1.0 mg/dL (88.4 …

Neonatal Peritoneal Dialysis

After completing this article, readers should be able to: 1. List the indications for peritoneal dialysis (PD) in neonates. 2. Delineate neonates who are poor candidates for PD. 3. Review the parameters of the PD prescription. 4. Review special nutrition considerations for neonates who are undergoing PD. 5. Review potential complications of PD in neonates. Peritoneal dialysis (PD) is generally considered the optimal dialysis modality for neonates. PD allows for the slow removal of fluid and solutes while avoiding hemodynamic instability. It is technically simple and, when necessary, can be performed continuously in the neonate hospitalized in the neonatal intensive care unit. In this review, we discuss the salient features of neonatal PD, including the rationale and indications for PD, its advantages and disadvantages, the PD prescription, nutritional considerations for the neonate undergoing PD, and the management of peritonitis. ### Rationale and Indications for Dialysis in Neonates Acute renal failure is common, occurring in as many as 23% of neonates hospitalized in neonatal intensive care units. There are excellent reviews in the literature that discuss the causes, pathophysiology, and medical management of acute renal failure in the neonate (see Acute Renal Failure Management in the Neonate in this issue of NeoReviews ). A partial list of the causes of acute renal failure in neonates is provided in Table 1. | Prerenal | || | | | Intrinsic | | | | Postrenal | | | Table 1. Causes of Acute Renal Failure The decision to initiate dialysis typically is necessitated by recalcitrant electrolyte abnormalities, worsening uremia, fluid overload, persistent acid-base abnormalities, …

130 Urinary Beta2-Microglobulin as an Indicator of Renal Lesion in Asphyxiated Neonates

BACKGROUND: Perinatal asphyxia can cause transient renal impairment or acute renal failure in neonates. Proximal tubular cells are extremely vulnerable to hipoxia.The ischemic injury results in elevated concentration of beta2microglobulin (beta2M) in urine.Urinary beta2M concentration increases with degree of tubular dysfunction.The aim of the study was to determine a concentration of beta2M in urine of asphyxiated and healthy neonates of varying gestational and postnatal age. STUDY AND THE CONTROL GROUPS: The study and the control groups were 141 neonates.The study group were 66 asphyxiated neonates,16 term and 50 preterm. Mean [SD] gestational age (GA) of term newborns was 38 (37 to 42) with mean [SD] birth weight 3290 g [703] and mean GA [SD] of preterm was 32 (30 to 36) mean [SD] birth weight 2070 g [548]. Criteria for inclusion were umbilical cord arterial pH less than 7.1 and BE less than minus 12 mmol/l. The control group were 75 neonates clinically stable 14 term (GA 37–42 mean [SD] 39 [1] mean birth weight [SD] 3440 g [500] and 57 preterm (GA 30- 36 mean [SD] 33 [2] mean [SD] birth weight 2061 g [552]. Both study and control group were divided into three subgroups of different maturation (A > 35, B-33–35, C 30–32 GA). METHODS: Urine samples were frozen at minus 20 C until assay. Beta2M was estimated in five samples on day 1, 3, 7, 14, 28 using competitive radioimmunoasay. RESULTS: We found statistically significant elevation of mean values of beta2M in urine of asphyxiated neonates compared to controls in all samples.The level of beta2M in preterm infants was significantly higher than that in term ones, both in study and control group during the entire first month of life.The highest values were observed in most immature neonates (GA 30–32). In group of asphyxiated and most immature neonates very high level of beta2M was still detected on day 28 while in fullterm it was almost normal.The beta2M excretion in asphyxiated neonates showed an increase on 1 and 3 day with a peak level at 7 day of age and than a slow decrease.Transient elevation of urinary beta2M were noted also in control group on day 3 with no significant differences between values of beta2M in the other samples in control group. We observed also correlation of beta2M with severity of perinatal asphyxia. The levels of beta2M were significantly increased in severe asphyxia group (pH less or equal 6.9) compared to mild asphyxia group. CONCLUSIONS: Measuring of beta2M can be non invasive method for determining a severity of perinatal asphyxia and renal maturation as well.

Indomethacin and renal impairment in neonates.

Renal impairment occurs in neonates receiving indomethacin for treatment of patent ductus arteriosus. Inhibition of cyclooxygenase within the neonatal kidney results in decreased prostaglandin synthesis and consequent reduction in renal perfusion. Indomethacin has been reported to cause short-term reduction in glomerular filtration that resolves after cessation of the drug. There is little information on the long-term effects of postnatal exposure to indomethacin. The aim of this study was to determine the incidence of renal impairment in infants treated with indomethacin in a single center, to determine whether there is evidence of renal impairment on day 30 or at discharge, and to identify risk factors for renal impairment. In a retrospective study, infants of less than 30 weeks completed gestation who received indomethacin to close the ductus arteriosus were matched with infants of the same gestation, birth weight, and severity of illness. Serum creatinine and glomerular filtration rates (GFR) were obtained prior to commencing indomethacin and on days 2, 7, and 30 following indomethacin administration. Acute renal failure was defined as an increase in creatinine of greater than 25%. Of those infants who were less than 30 weeks completed gestation, 24% had acute renal failure following indomethacin administration. There was a significant elevation in serum creatinine on day 2 and day 7 ( P<0.0001, P=0.002) and a decrease in GFR on day 2 and day 7 ( P<0.0001, P=0.01) following administration of indomethacin. Renal function had normalized by day 30 or discharge. The incidence of acute renal failure in neonates treated with indomethacin is clinically significant. Renal function returns to normal by day 30. Linear regression found no statistical significance for gestational age, day of indomethacin dosing, Clinical Risk Index for Babies (CRIB) score, and presence of an umbilical artery catheter to confound the effect of indomethacin on renal function.

Acute Renal Failure in the Neonatal Period

Acute renal failure (ARF) is a common problem in the neonatal intensive care unit (NICU). In most cases, ARF is associated with a primary condition such as sepsis, metabolic diseases, perinatal asphyxia and/or prematurity. This retrospective study investigated the course of illness, therapeutic interventions, early prognosis and risk factors associated with development of ARF in the neonatal period. A total of 1311 neonates were treated in our NICU during the 42‐month study period, and 45 of these babies had ARF. This condition was defined as serum creatinine level above 1.5 mg/dL despite normal maternal renal function. The data collected for each ARF case were contributing condition, cause and clinical course of ARF, gestational age and birth weight, age at the time of diagnosis, treatment, presence of perinatal risk factors and need for mechanical ventilation. The frequency of ARF in the NICU during the study period was 3.4%. Premature newborns constituted 31.1% of the cases. The mean birth weight in the group was 2863 ± 1082 g, and the mean age at diagnosis was 6.2 ± 7.4 days. The causes of ARF were categorized as prerenal in 29 patients (64.4%), renal in 14 patients (31.1%) and postrenal in 2 patients (4.4%). Forty‐seven percent of the cases were nonoliguric ARF. Asphyxia was the most common condition that contributed to ARF (40.0%), followed by sepsis/metabolic disease (22.2%) and feeding problems (17.8%). Therapeutic interventions were supportive in 77.8% of the cases, and dialysis was required in the other 22.2%. The mortality rate in the 45 ARF cases was 24.4%. Acute renal failure of renal origin, need for dialysis, and need for mechanical ventilation were associated with significantly increased mortality (p < 0.05). There were no statistical correlations between mortality rate and perinatal risk factors, oliguria, prematurity or blood urea nitrogen and creatinine levels. The study showed that, at our institution, ARF in the neonatal period is frequently associated with preventable conditions, specifically asphyxia, sepsis and feeding problems. Supportive therapy is effective in most cases of neonatal ARF. Acute renal failure of renal origin, need for dialysis, and need for mechanical ventilation were identified as indicators of poor prognosis in these infants. Early recognition of risk factors and rapid effective treatment of contributing conditions will reduce mortality in neonatal ARF.

Nimesulide, a cyclooxygenase-2 preferential inhibitor, impairs renal function in the newborn rabbit.

Tocolysis with nonsteroidal anti-inflammatory drugs (NSAIDs) has been widely accepted for several years. Recently, the use of the cyclooxygenase-2 (COX2) preferential NSAID nimesulide has been proposed. However, data reporting neonatal acute renal failure or irreversible end-stage renal failure after maternal ingestion of nimesulide question the safety of this drug for the fetus and the neonate. Therefore, this study was designed to define the renal effects of nimesulide in newborn rabbits. Experiments were performed in 28 newborn rabbits. Renal function and hemodynamic parameters were measured using inulin and para-aminohippuric acid clearances as markers of GFR and renal blood flow, respectively. After a control period, nimesulide 2, 20, or 200 microg/kg was given as an i.v. bolus, followed by a 0.05, 0.5, or 5 microg.kg(-1).min(-1) infusion. Nimesulide administration induced a significant dose-dependent increase in renal vascular resistance (29, 37, and 92%, respectively), with a concomitant decrease in diuresis (-5, -23, and -44%), GFR (-12, -23, and -47%), and renal blood flow (-23, -23, and -48%). These results are in contrast with recent reports claiming that selective COX2 inhibition could be safer for the kidney than nonselective NSAIDs. These experiments confirm that prostaglandins, by maintaining renal vasodilation, play a key role in the delicate balance regulating neonatal GFR. We conclude that COX2-selective/preferential inhibitors thus should be prescribed with the same caution as nonselective NSAIDs during pregnancy and in the neonatal period.

Association between heat shock protein 72 gene polymorphism and acute renal failure in premature neonates.

Heat shock protein (HSP)70 plays an important role in the ischemic tolerance of fetal and neonatal kidney. We have investigated the association of genetic polymorphisms of the constitutive HSP70 (HSP73) and the inducible HSP70 (HSP72) encoding genes with the risk of acute renal failure (ARF) in very low birth weight (VLBW) neonates. Thirty-seven VLBW neonates with ARF and 93 VLBW neonates without ARF were enrolled in the study. The presence of HSP72 (1267)AG and HSP73 (190)GC polymorphism was analyzed from dried blood samples by PCR and restriction length fragment polymorphism. Allelic prevalence was related to reference values obtained in 131 healthy adults. Stepwise binary logistic regression was applied to determine the independent effect of the established risk factors to the development of ARF. Sixteen of 37 VLBW neonates with ARF and 18 of 93 VLBW neonates without ARF were homozygous for HSP72 (1267)G allele (p </= 0.01). The association between HSP72 (1267)GG genotype and ARF remained at the level of significance (p = 0.05) when it was adjusted for established risk factors of neonatal ARF. Prevalence of HSP72 (1267)GG was also higher in VLBW neonates than in the reference population (p < 0.05) and in VLBW neonates with infant respiratory distress syndrome than in those without (p < 0.001). We found that in VLBW neonates carrying HSP72 (1267)GG genetic variation, which is associated with low inducibility of HSP72, the risk of ARF was increased. Therefore, VLBW neonates with (1267)GG might express less HSP72 and might be less protected against ARF.

Interleukin genetic variants and the risk of renal failure in infants with infection.

Systemic infection is a major risk factor for the development of neonatal acute renal failure (ARF). We investigated whether genetic polymorphisms of tumor necrosis factor (TNF)-alpha, interleukin (IL)-1beta, IL-6, and IL-10 genes leading to a more intense inflammatory response might predispose very low birth weight (VLBW) infants to the development of ARF in severe infection. The medical records of 92 VLBW newborns (birth weight under 1,500 g) with systemic infection were analyzed. ARF developed in 38 infants during the 1st postnatal week, while 54 neonates exhibited normal renal function. The variants of TNF-alpha, IL-1beta, IL-6, and IL-10 genes were determined from dried blood samples with polymerase chain reaction and restriction fragment length polymorphism methods. The allele frequencies did not differ in ARF and in non-ARF babies, while the (TNF-alpha /IL-6) AG/GC or AG/CC haplotypes were more often present in ARF (26% vs. 6%, P<0.01). The single presence of TNF-alpha, IL-1beta, IL-6, and IL-10 variants does not influence the development of ARF, but the constellation of TNF-alpha and IL-6 genetic variants is associated with ARF. We hypothesize that the simultaneous presence of these polymorphisms might lead to an enhanced inflammatory response in the kidneys in babies with infection.

Renal aspects of the term and preterm infant: a selective update.

This review discusses new aspects of normal and abnormal renal development that expand insight into the adaptation of the neonatal kidneys to the stress of extrauterine life. Highlighted are some pitfalls in measuring glomerular filtration rate in the neonate mainly caused by postnatal fluctuations in serum creatinine levels. Serum creatinine levels are correlated with the authors' recent finding of tubular reabsorption of creatinine in the immature neonatal kidney. Renal maldevelopment in premature and small-for-date babies has been shown related to serious medical problems in adult life, including hypertension. This finding presents the pediatrician with a new role in the time-honored vocation of preventing disease. Mutations in several genes may be responsible for most cases of congenital or hereditary renal aberrations. Two renal disorders, congenital nephrotic syndrome and neonatal acute renal failure, and one form of treatment modality of newborn infants, renal replacement therapy, are discussed in detail. These conditions are rare in general pediatric practice, but they illustrate some of the new developments in the renal care of the newborn. A word of caution is offered about the use of nonsteroidal anti-inflammatory drugs during pregnancy and the newborn period. All nonsteroidal anti-inflammatory drugs administered indirectly to the unborn fetus and directly to the young newborn impair renal structure (fetus) and function (both fetus and newborn). The new data have been obtained with genetic and molecular biology techniques and with established methods of developmental renal physiology. A better understanding of the pathogenesis of neonatal renal disorders will result in new diagnostic procedures and improved preventive and therapeutic possibilities relevant to the neonate with a renal disorder.

Acute oliguric renal failure in hypoxic neonates born at full term

Acute renal failure (ARF) is a frequent clinical condition in neonatal intensive care units (NICU). The leading cause of neonatal ARF is perinatal asphyxia (PS). The aim of this study was to examine the relationship between the degree of PS and the severity of ARF in term neonates. A prospective survey of 31 term neonates with Ps and but without congenital malformations or sepsis was performed in NICU of the regional Hospital of Gynaecology and Obstetrics in Belgrade (average number of deliveries about 6000 per year). ARF was diagnosed in the first 7 days of life when plasma creatinine was above 133 mumol/L for at least 48 hours while maternal renal function was normal. The degree of PS was determined according to Apgar score (AS) at 1 min. The severe PS was defined as AS < 3 and moderate PS as AS 4-6. Twenty neonates (64%) had oliguric ARF with urine output of 0.37 +/- 0.16 ml/kg/h while the others had nonoliguric ARF with urine output of 2.4 +/- 0.7 ml/kg/h. Most of neonates with oliguric ARF (65%) had severe perinatal asphyxia while in those with nonoliguric ARF moderate perinatal asphyxia predominated (73%). During hypoxic-ischaemic events many organs are injured, and the most vulnerable ones are kidneys and central nervous system. Our results showed a strong connection between perinatal asphyxia and A, which was in accordance with the results of other studies. Neonates with severe perinatal asphyxia had serious impairment of renal function, which was confirmed with strong correlation between Apgar score and plasma creatinine. In neonates with oliguric ARF, but not in those with nonliguric ARF, the highly positive linear correlations were found between AS and urinary output (r = 0.77; p < 0.01), plasma creatinine (r = 0.78; p < 0.01), fractional excretion of sodium (r = 0.76; p < 0.01), and index of renal failure (r = 0.80; p < 0.01). Only in oliguric neonates with severe perinatal asphyxia (31%) the outcome was fatal. We conclude that in tgerm neonates with severe perinatal asphyxia oliguric ARF was the predominant type of ARF. There is a good prediction of the severity of oliguric ARF according to the degree of perinatal asphyxia determined by Apgar score at 1 min.

Variance of ACE and AT1 receptor gene does not influence the risk of neonatal acute renal failure.

High neonatal activity of the renin-angiotensin system (RAS) is crucial for the maintenance of glomerular filtration of the newborn. The aim of the present study was to investigate whether genetic polymorphisms leading to lower angiotensin converting enzyme activity (ACE) or impaired functionality of angiotensin II (AII) type 1 receptor (AT1R) might predispose very low birth weight newborns (VLBWs) to the development of acute renal failure (ARF). The medical records of 110 VLBW infants were analyzed. ARF developed in 42 of them during the first postnatal week, while 68 neonates exhibited normal renal function. The ACE I/D polymorphism and the A1166C variants of AT1R were determined from dried blood samples. The frequency of the ACE I allele did not differ in ARF and non-ARF groups (0.307 and 0.284); the frequency of the AT1R C1166 variant was also the same in ARF and non-ARF groups (0.250 and 0.227). Although low activity of RAS has been implicated in the development of neonatal ARF and data indicated that the functionality of RAS is influenced by the I/D variants of the ACE gene and the A1166C variant of the AT1R gene, we could not demonstrate any effect of these polymorphisms on the development of ARF in VLBW infants.

Fungal Bezoars as a Cause of Renal Insufficiency in Neonates and Infants-Recommended Treatment Strategy

No AccessJournal of UrologyUrological Survey: Abstracts: Pediatric Urology1 Jan 1999Fungal Bezoars as a Cause of Renal Insufficiency in Neonates and Infants-Recommended Treatment Strategy D. Visser, L. Monnens, W. Feitz, and B. Semmekrot D. VisserD. Visser More articles by this author , L. MonnensL. Monnens More articles by this author , W. FeitzW. Feitz More articles by this author , and B. SemmekrotB. Semmekrot More articles by this author View All Author Informationhttps://doi.org/10.1016/S0022-5347(01)62176-1AboutFull TextPDF ToolsAdd to favoritesDownload CitationsTrack CitationsPermissionsReprints ShareFacebookLinked InTwitterEmail "Fungal Bezoars as a Cause of Renal Insufficiency in Neonates and Infants-Recommended Treatment Strategy." The Journal of Urology, 161(1), p. 368 Departments of Pediatrics and Pediatric Urology, University Hospital Nijmegen, The Netherlands© 1999 by American Urological Association, Inc.FiguresReferencesRelatedDetails Volume 161Issue 1January 1999Page: 368 Advertisement Copyright & Permissions© 1999 by American Urological Association, Inc.MetricsAuthor Information D. Visser More articles by this author L. Monnens More articles by this author W. Feitz More articles by this author B. Semmekrot More articles by this author Expand All Advertisement PDF downloadLoading ...

Fungal Bezoars as a Cause of Renal Insufficiency in Neonates and Infants-Recommended Treatment Strategy

Fungal bezoars may be a cause of urinary tract obstruction and acute renal failure in neonates and young infants. We describe a female very low birth weight infant (25+3 weeks, 795 gram) who developed renal insufficiency on the basis of systemic fungal infection with fungal bezoars in both kidneys. The girl was treated by local irrigation of the kidneys and bladder with amphotericin B via percutaneously inserted bilateral nephrostomy catheters, in combination with intravenous fluconazol. Renal function subsequently improved and after 11 weeks of treatment the bezoars had disappeared sonographically. Follow-up of this child and the one we similarly treated for fungal bezoars before, however, shows suboptimal renal function as assessed by the clearance of creatinine and the mercapto acetyl triglycine scan (MAG III). Until now, insufficient data are available yet to assess with certainly the long-term effects of fungal bezoars on renal function. Based on our experience and a review of the recent literature (1980-1996) on systemic candidal infections in premature infants, we recommend to perform regular renal ultrasound in any case of systemic candidal infection in a prematurely born infant. If candidal bezoars are found with pelvic obstruction, we suggest to start treatment by the insertion of bilateral nephrostomy catheters and local irrigation with amphotericin B in combination with systemic antifungal agents, aiming at both the restoration of renal function and the eradication of the fungal infection.

Acute Renal Failure in Neonates: A Prospective Study

Babies admitted to a neonatal intensive care unit in whom acute renal failure developed were studied prospectively to determine the etiology, course, and outcome of the disorder, as well as the reliability of renal indices in distinguishing intrinsic from prerenal renal failure. The incidence of neonatal acute renal failure was 3.6% (22/603). The most frequent causes were hypotension (86%), respiratory distress syndrome (41%), sepsis (32%), and asphyxia (27%). Half of the patients were born at less than 32 weeks' gestation and had a birth weight of less than 1500 gm. There was intrinsic renal failure in 15 neonates and prerenal failure in seven. Renal indices (urine-to-plasma ratio of osmolality, fractional excretion of sodium, and renal failure index) were not reliable in differentiating between intrinsix or prerenal failure. Mortality from renal failure was high at 77%. Survivors of neonatal acute renal failure who had no underlying congenital anomalies of the urinary tract did not appear to exhibit residual renal impairment during follow-up evaluation. It is important to identify those clinical indices that can be used in determining the diagnosis and prognosis of acute renal failure in neonates, particularly in very premature, low-birth-weight babies.

Acute renal failure in neonates: incidence, etiology and outcome.

Acute renal failure (ARF) occurs in as many as 8% of neonates admitted to neonatal intensive care units. Most often, ARF is recognized because of oliguria (urinary flow rate less than 1 ml/kg per hour) although nonoliguric neonatal ARF is being detected with increasing frequency. Among urinary indices utilized to differentiate oliguric neonatal ARF from prerenal oliguria, a fractional excretion of sodium greater than 3% or a renal failure index (RFI) greater than 3 are helpful in confirming ARF. Such indices must be viewed with caution in very premature infants who may have a physiologically high sodium excretion rate and in neonates with the nonoliguric form of ARF. The mortality of oliguric neonatal renal failure may be as high as 60% in medical ARF and even higher in neonates with congenital heart disease, or with anomalies of the genitourinary system. In contrast, nonoliguric renal failure in neonates has an excellent prognosis. Long-term abnormalities in glomerular filtration rate and in renal tubular function are common in survivors of neonatal ARF.

Prognostic Factors in Neonatal Acute Renal Failure

Sixteen infants, 2 to 35 days of age, had acute renal failure, a diagnosis based on serum creatinine concentrations greater than 1.5 mg/dL for at least 24 hours. Eight infants were oliguric (urine flow less than 1.0 mL/kg/h) whereas the remainder were nonoliguric. To determine clinical parameters useful in prognosis, urine flow rate, duration of anuria, peak serum creatinine, urea (BUN) concentration, and nuclide uptake by scintigraphy were correlated with recovery. Nine infants had acute renal failure secondary to perinatal asphyxia, three had acute renal failure as a result of congenital cardiovascular disease, and four had major renal anomalies. Four oliguric patients died: three of renal failure and one of heart failure. All nonoliguric infants survived with mean follow-up serum creatinine concentration of 0.8 +/- 0.5 (SD) mg/dL whereas that of oliguric survivors was 0.6 +/- 0.3 mg/dL. Peak serum creatinine concentration did not differ between those patients who were dying and those recovering. All infants who were dying remained anuric at least four days and revealed no renal uptake of nuclide. Eleven survivors were anuric three days or less, and renal perfusion was detectable by scintigraphy in each case. However, the remaining survivor (with bilateral renal vein thrombosis) recoveredmore » after 15 days of anuria despite nonvisualization of kidneys by scintigraphy. In neonates with ischemic acute renal failure, lack of oliguria and the presence of identifiable renal uptake of nuclide suggest a favorable prognosis.« less

Prognostic Factors in Neonatal Acute Renal Failure

Sixteen infants, 2 to 35 days of age, had acute renal failure, a diagnosis based on serum creatinine concentrations greater than 1.5 mg/dL for at least 24 hours. Eight infants were oliguric (urine flow less than 1.0 mL/kg/h) whereas the remainder were nonoliguric. To determine clinical parameters useful in prognosis, urine flow rate, duration of anuria, peak serum creatinine, urea (BUN) concentration, and nuclide uptake by scintigraphy were correlated with recovery. Nine infants had acute renal failure secondary to perinatal asphyxia, three had acute renal failure as a result of congenital cardiovascular disease, and four had major renal anomalies. Four oliguric patients died: three of renal failure and one of heart failure. All nonoliguric infants survived with mean follow-up serum creatinine concentration of 0.8 +/- 0.5 (SD) mg/dL whereas that of oliguric survivors was 0.6 +/- 0.3 mg/dL. Peak serum creatinine concentration did not differ between those patients who were dying and those recovering. All infants who were dying remained anuric at least four days and revealed no renal uptake of nuclide. Eleven survivors were anuric three days or less, and renal perfusion was detectable by scintigraphy in each case. However, the remaining survivor (with bilateral renal vein thrombosis) recovered after 15 days of anuria despite nonvisualization of kidneys by scintigraphy. In neonates with ischemic acute renal failure, lack of oliguria and the presence of identifiable renal uptake of nuclide suggest a favorable prognosis.