Renal cortical and renal medullary necrosis in the first 3 months of life.

Renal cortical necrosis, renal medullary necrosis, and combined renal cortical-medullary necrosis result from renal ischemia without vascular occlusion. Renal hypoperfusion and ischemic injury in infants have been ascribed to massive blood loss, hemolytic disease, septicemia, and severe hypoxemia. In a postmortem study we identified 82 cases among 1,638 autopsies during the 20 years between 1970 and 1989 in infants 3 months old or less at the time of death. The frequency of renal necrosis in autopsy cases increased significantly during the last 6 years of the study. The distribution of the renal lesion was cortical in 28, medullary in 23, and combined in 31. Forty infants carried diagnoses of congenital heart disease, 17 of asphyxial shock, 9 of sepsis, 3 of infectious myocarditis, 9 of major malformations, 4 of anemic shock, 1 of vascular malformation, and 1 of gastroenteritis and dehydration. A significantly higher proportion of babies with congenital heart disease had cortical involvement. Comparison of clinical characteristics revealed a significantly higher frequency of prematurity, respiratory distress syndrome, bleeding diathesis, and possibly sepsis in the children with congenital heart disease, suggesting that these factors are important in the pathogenesis of the renal lesion. Fourteen infants underwent cardiac catheterization; there was no demonstrable association between the renal lesions and the use of radiographic contrast medium. We conclude that severe congenital heart disease itself is a risk factor for life-threatening renal cortical and medullary necrosis.

Real-time US guidance during renal biopsy in children: a different approach. Technical note.

To minimize procedural failures and complications, a real-time ultrasound (US) approach was developed for percutaneous renal biopsy in the pediatric population. With use of a 3- or 5-MHz transducer, the medial border of the kidney is localized and a line, which parallels the renal axis, is drawn on the skin. The lower pole and renal hilum are identified, and lines are drawn perpendicular to the long axis. After the patient is sedated, the entry site is selected above the lower pole. The transducer is placed on the child's side in an oblique transverse plane parallel to the axis of the kidney, the needle is guided into the renal cortex, and a specimen is obtained. Sixty-five biopsies were performed in 63 children. Fifty-five specimens were obtained from native kidneys. Success was achieved in all cases with only three minor complications. This approach appears to be an easy, safe, and accurate guide for renal biopsy in the pediatric population.

Effects of prenatal ethanol exposure on postnatal renal function and structure in the rat.

Effects of prenatal ethanol exposure on postnatal renal function and structure in the rat. Renal function and morphology were studied in 90-day-old offspring of ethanol-fed (E) rats and were compared to pair-fed control (C) animals. Compared to C rats, E rats were smaller at birth, had higher fractional sodium excretion (p less than 0.01) and lower fractional potassium excretion (p less than 0.01). In E rats, sodium (Na) restriction resulted in a significant increase in urine flow and Na wastage, whereas C rats remained in Na balance. E rats developed hyperkalemia, when potassium (K) intake was increased from 2.8 to 14 mEq/day. Baseline creatinine clearance, urine and blood osmolalities and pH, plasma electrolytes and aldosterone concentrations were similar in both groups. There was no significant difference in wet or dry kidney weight, renal water content, or renal tissue concentrations of Na or K between the two groups. No difference was found in gross morphology or light microscopic appearances of the kidneys between E and C rats. Thus rats exposed to ethanol during fetal life have a defect in urine concentration and Na conservation when fed a low Na diet and a defect in K excretion when given a K load without evidence of any gross or light microscopic renal structural abnormalities at 90 days of age.

The effect of aggressive nutrition on infection rates in patients maintained on peritoneal dialysis.

Aggressive nutrition has been reported to improve growth parameters in children undergoing peritoneal dialysis. The current study reports the effect of a program of aggressive nutrition, started in 1/1988, on catheter-related infection rates in children undergoing chronic peritoneal dialysis. A combination of high calorie foods, supplements, "candy bar diets", and, when necessary, modular gastrostomy feedings, to provide 3-4 gm/kg/d and 100-120 kcal/kg/d was used. Peritonitis and catheter infection rates were assessed. A total of 37 pediatric patients underwent peritoneal dialysis from 1/1986-7/1990, with a total cumulative experience of 596 patient months. The peritonitis rate decreased from 1 episode/5.53 patient-month in 1987 to 1 episode per 46 patient-month in 1990. There was no significant effect on the catheter infections or the number of admissions/patient month. However, there was a 55% decline in the number of hospitalization days/patient month (p less than 0.01). The decrease in the peritonitis rate was independent of the modality of peritoneal dialysis or the usage of ultraviolet connecting devices. In 10 patients followed sequentially, the peritonitis rate was less (1 episode/23.5 patient months) after gastrostomy tube placement and feedings than before gastrostomy tube placement (1 episode/8.28 patient months) (p less than 0.01). There were no significant differences in serum albumin or total protein levels between the two observation periods. We conclude that adequate nutrition may play a role in decreasing the peritonitis rate in children maintained on peritoneal dialysis and speculate improved white cell function as a possible underlying mechanism.

Escherichia coli cellulitis in children with idiopathic nephrotic syndrome.

Although Streptococcus pneumoniae is traditionally considered the preponderant bacterial pathogen in children with nephrotic syndrome, recent data suggest an increase of infections with encapsulated gram-negative organisms. We report two children with idiopathic nephrotic syndrome in relapse who developed spontaneous Escherichia coli cellulitis. The organism was recovered from the cellulitis tissue aspirate of one, and from the blood of the other. Both patients responded to appropriate antibiotic therapy. Initial treatment of sepsis, peritonitis or spontaneous cellulitis in nephrotic patients should include broad spectrum antibiotic coverage pending results of appropriate cultures.

Reflux nephropathy.

This article reviews current concepts of reflux nephropathy, including the pathophysiology, diagnosis, relationship to infection, role in causing end-stage renal disease, and appropriate treatment and management. The condition is defined from a epidemiologic point of view herein, and attention also is given to possible progressions this condition can take.

Metabolism and pharmacokinetics of acetaminophen in a severely poisoned young child.

A 1-year-old child with severe acetaminophen (APAP) poisoning after ingestion of 10 gm APAP demonstrated central nervous system depression, shock, hypothermia, and metabolic acidosis. There was dramatic improvement during treatment with intravenously administered N-acetylcysteine (NAC) and hemodialysis, and the patient recovered without sequelae. A detailed study of APAP metabolism was carried out during the initial 72 hours after ingestion. APAP-sulfate and APAP-glucuronide accounted for 29% and 33%, respectively, of total drug in urine, whereas cysteine and NAC conjugates accounted for only 12%. The low incidence of severe toxicity in children after overdoses of APAP may be related to greater capacity to metabolize APAP via a nontoxic pathway.

Pharmacokinetics of severe theophylline intoxication managed by peritoneal dialysis.

In a patient severely poisoned with theophylline, saturation kinetics were demonstrated at serum concentrations > 35 micrograms/ml with subsequent conversion to first order kinetics (t 1/2 = 5.4 h). Peritoneal dialysis was used to enhance the drug's removal. The mean theophylline clearance was greater for dialysate (5.11 ml/min) than for urine (1.98 ml/min) or gastric fluid (0.32 ml/min). Urinary elimination occurred as a constant first order process (t 1/2 = 4.3 h). Peritoneal dialysis is a valuable early adjunct in the management of severe theophylline intoxication.

Acute renal failure in Reye's syndrome.

Three patients with initial clinical manifestations and biochemical findings suggestive of a diagnosis of Reye's syndrome had acute renal insufficiency develop and had evidence of consumptive coagulopathy, not generally considered features of the syndrome. As a group, they could not be distinguished, either on the basis of their clinical manifestations or liver pathologic findings, from the 17 patients with Reye's syndrome without renal failure seen in our institution during the same period of time. The use of osmotic diuretics in an effort to decrease cerebral edema may be life threatening in these patients with compromised renal function since hypervolemia, cardiac failure, and worsening of cerebral edema may occur.

A case of generalized Wegener's granulomatosis in childhood: successful therapy with cyclophosphamide.

An 11-year-old white boy had Wegener's granulomatosis, a rare condition in the pediatric age group. The clinical course, pathological findings, and mode of treatment are outlined. The disease is in remission on a regimen of cyclophosphamide therapy as judged by both clinical and pathological criteria. This syndrome with protein manifestations should be considered in children with symptoms of repeated upper respiratory tract infections along with pulmonary and renal involvement. Early renal biopsy helps to establish the diagnosis of generalized involvement and to guide the course of treatment. Follow-up renal biopsies may serve as an indication for the continuation of treatment. Cytotoxic agents, especially cyclophosphamide, dramatically alter the course of the disease.

Natriuresis-induced protection in acute myohemoglobinuric renal failure without renal cortical renin content depletion in the rat.

The interrelationships of renal cortical renin content RCRC, sodium chloride excreting and the severity of renal failure were studied in the glycerol-induced acute myohemoglobinuric renal failure model in the rat. Protocols were designed to increase sodium chloride excretion without necessarily resulting in RCRC depletion. Our data fail to demonstrate a relationship between RCRC and severity of renal failure, but they demonstrate an excellent inverse correlation between the sodium chloride excretion of the animals in the 24 h prior to glycerol administration and the severity of resulitng renal failure. The protection of long-term saline-drinking animals should properly be ascribed to the associated natriuresis which develops much before RCRC depletion during the time course of saline drinking. The exact mechanism by which natriuresis exerts its protective effect needs further elucidation, but our data argue against a major role for RCRC in the pathogenesis of acute experimental renal failure.

Pulmonary calcifications in a child with renal failure.

A chronically azotemic 2 6/12 boy developed diffuse, bilateral pulmonary calcification. The radiographic features and pathologic mechanism of such pulmonary calcification is discussed.

Management of hypertensive crisis in children.

The availability and rapidity of onset of pharmacologic agents for the treatment of hypertensive crisis allow the pediatrician to treat nearly every case effectively. Diazoxide seems to be the agent of choice as a first drug for the patient with encephalopathy. Failure of the blood pressure to respond to this agent should lead to consideration of the use of sodium nitroprusside. The possibility of the presence of a cathecholamine-secreting tumor should also be considered in these rare patients. In less severe cases, reserpine and hydralazine--alone or in combination--offer sufficiently rapid and prolonged action to prevent the development of encephalopathy in patients with acute elevations of blood pressure.