Hypertension in the first month of life.

We reviewed our 10-year experience with neonatal hypertension. Fifty-three cases were identified, which represented 0.7% of all neonatal tertiary care admissions. Causes were identified in 23 (43%) neonates. These included acute tubular necrosis (n = 7), renal vascular abnormalities (n = 8), renal structural abnormalities (n = 4), interstitial nephritis (n = 2), and coarctation of the aorta (n = 2). No cause was identified in 30 (57%) infants. If the two neonates with coarctation are excluded, infants who had normal urinalyses, blood urea nitrogen (BUN), serum creatinine and plasma renin activity (PRA), had non-malignant hypertension that tended to be short-lived and always resolved spontaneously. In contrast, a cause of hypertension was found in 68% of those having an abnormal urinalysis, BUN, serum creatinine or PRA. There were two hypertensive deaths in this group. While the hypertension was usually more prolonged, it still generally resolved spontaneously by 1 year of age or following corrective surgery. Our experience indicates that diagnostic studies can be postponed if the urinalysis, BUN, serum creatinine and PRA are normal and if coarctation of the aorta has been excluded. If these preliminary studies are abnormal, however, a renal cause is likely and further studies are indicated.

A 20-year population-based study of postdiarrheal hemolytic uremic syndrome in Utah.

OBJECTIVE: To determine epidemiologic features, trends in frequency, and predictors of clinical outcome of postdiarrheal hemolytic uremic syndrome (HUS) in Utah. DESIGN: A 20-year population-based study of HUS with a review of the HUS registry, hospital records, transplant registry, and a survey of pediatricians and pediatric nephrologists to ensure completeness of ascertainment. POPULATION: All Utah residents under 18 years of age with HUS occurring after a diarrheal prodrome between 1971 and 1990. OUTCOME MEASURES: Incidence of HUS, severity, complications, and long-term sequelae. RESULTS: There were 157 cases during 20 years; 140 (89%) occurred after a diarrheal prodrome. The mean annual incidence was 1.42/100,000 children (range 0.2 to 3.4/100,000 children/year). Periods of high incidence occurred; however, there was no overall sustained increase in incidence. Escherichia coli O157:H7 was isolated from the stool of 62% of children who had specimens submitted. There were no differences between the first and second decade in the proportion with diarrheal prodrome, bloody diarrhea, most abnormal laboratory values, hospital course, or outcome. However, admission laboratory abnormalities were more severe during the first decade suggesting a delay in diagnosis. Age < 2 years, anuria before admission, and higher white blood cell counts on admission predicted severe disease. Bad outcome (death, end-stage renal disease, or stroke) occurred in 11%; 5% died. Chronic renal sequelae, usually mild, were found on follow-up (median 6.5 years) in 51% of survivors. CONCLUSIONS: HUS has been an important clinical and public health problem in Utah for 20 years. The consistency of the clinical and epidemiologic features over 2 decades suggests that a common etiologic agent has accounted for most cases of HUS in this region since 1971.

New syndrome involving the visual, auditory, respiratory, gastrointestinal, and renal systems.

A previously undescribed fatal multisystem syndrome involving the eyes, ears, lungs, intestines, and kidneys occurred in sibs. They both presented during early childhood with cataracts, otitis media, intestinal malabsorption, chronic respiratory infection, and failure to thrive. Later, they developed recurrent pneumonia (one was shown to have immotile bronchial cilia) and progressive azotemia leading to end-stage renal disease (ESRD) by late childhood. Both died of overwhelming infection (sepsis, meningitis). An autosomal recessive mode of inheritance is proposed since the normal parents were distant cousins, and 4 other sibs were normal.

Hemolytic-uremic syndrome in adolescents.

OBJECTIVE: To compare the epidemiological characteristics, clinical features, and outcome of adolescents with hemolytic-uremic syndrome (HUS) with those of children with HUS. DESIGN: A retrospective descriptive study using data stored in the computerized Utah HUS registry. SETTING: The HUS registry contains data on postdiarrheal and nondiarrheal HUS cases since 1970 in which the patients were younger than 18 years of age at the time of diagnosis and includes virtually all Utah cases as well as those referred from surrounding states. PATIENTS: Seventeen adolescents (age, 12-17 years) and 276 younger patients from September 30, 1970, through December 5, 1993, who met the diagnostic criteria for HUS. MAIN OUTCOME MEASURES: Age, sex, seasonality, prodromal features (eg, antecedent diarrhea), laboratory values, hospital course, outcome, and chronic sequelae. RESULTS: The 17 adolescent patients, who composed 5.8% of the study population, experienced a course of the disease that was similar to that of the younger patients. Diarrhea preceded HUS in approximately 90% of the patients in both groups. Laboratory values were similar in teenagers and younger patients. The hospital courses were also similar; seizures occurred in almost 20%, and hypertension and oligoanuric renal failure occurred in most. Two (12%) of the teenagers and 7 (2.4%) of the younger patients died during the acute phase of the syndrome (P = .09); almost 50% of both groups experienced 1 or more chronic renal sequelae. End-stage renal disease has occurred in 1 (5.8%) of the teenagers and 6 (2.2%) of the children. At follow-up, 1 or more years (median, 5 years) after the onset of HUS, hypertension was present in 22% of the teenagers and 6.7% of the preteens (P = .14). A below-normal glomerular filtration rate was seen in approximately 30% of both groups; proteinuria was noted in approximately 25% of both groups. Approximately 10% of both groups had a combination of proteinuria and a low glomerular filtration rate and are, therefore, at risk for eventual end-stage renal disease. CONCLUSIONS: In our region of the Intermountain West, HUS in adolescents closely resembles that seen in children and the outcome is more favorable than that experienced by adults.

Renin-dependent hypertension in children with reflux nephropathy.

In children with reflux nephropathy renin-dependent hypertension may develop. Two girls with reflux nephropathy, hypertension, elevated plasma renin activity, but normal (Case I) and near normal (Case 2) serum creatinines are described. These cases suggest that reflux nephropathy can activate the renin-angiotensin system and that the renin inhibitors, methyldopa and propranolol, an useful in managing this type of hypertension.

Conservative management of neonatal renal artery embolism.

Renal artery thrombosis or embolism associated with the use of an umbilical arterial catheter can cause renin-dependent hypertension in the neonate. The tip of the catheter should therefore be kept well below the origin of the renal arteries and the infant's blood pressure monitored. Moreover, since the pressor hypertension may be transient and kidney function may return, a period of medical management should be attempted before proceeding to nephrectomy.

Acute renal failure in idiopathic nephrotic syndrome.

Acute renal failure (ARF) associated with idiopathic nephrotic syndrome has been reported in adults with advanced age but is a rare event in children. We have reviewed the literature on this subject and report an additional pediatric case. The pathogenetic mechanisms which may lead to ARF during the course of idiopathic nephrotic syndrome are reviewed with a brief discussion of the role of angiotensin II and angiotensin converting enzyme inhibition in this setting. Although no consensus has emerged for the prevention and treatment of ARF in patients with nephrotic syndrome, a combination of salt-poor albumin and diuretics to reduce interstitial edema may be beneficial as a preventive measure. Once acute tubular necrosis is diagnosed, dialysis may be indicated. In the majority of reports the prognosis for recovery of renal function has been good even in patients in whom long-term dialysis was required.

Clustering of post-diarrheal (Shiga toxin-mediated) hemolytic uremic syndrome in families.

AIMS: 1. To study the epidemiological and clinical features of Shiga toxin (Stx)-mediated (post-diarrheal) hemolytic uremic syndrome (HUS) occurring in more than 1 family member. 2. To compare familial with non-familial episodes, and concurrent familial with non-concurrent familial cases. 3. To determine the likelihood of Stx HUS occurring in a second family member. METHODS: A retrospective review from January 1970 through September 2001 of families in whom Stx HUS occurred in more than 1 family member was conducted using a computerized HUS registry. It contains information on 373 episodes that occurred in 356 families from Utah and neighboring states. Cases were categorized as being either concurrent (i.e., occurring within a month of one another) or non-concurrent, and the study was limited to those with typical (post-diarrheal) episodes. RESULTS: HUS occurred in 2 or more family members in 17 (4.8%) of the families in our registry. In 12 (3.4%) of these families episodes occurred with days to weeks of each other; in 5 families (1.4%) episodes were separated by intervals of several years. There were no statistically significant differences in demographic, seasonal, laboratory, clinical, or outcome variables between familial subsets (concurrent versus non-concurrent) or between familial and non-familial cases. CONCLUSIONS: When a child is diagnosed with D+ HUS, there is an increased risk that a second family member will also develop HUS; most often within days to weeks (i.e., within a month), but in some cases episodes may be separated by intervals of years. Non-concurrent cases suggest common environmental risk factors, or perhaps a genetic predisposition. Concurrent cases suggest a common source of infection or person-to-person transmission; a genetic predisposition cannot be excluded. These observations suggest that siblings of an index case who develop diarrhea should be kept under close surveillance.

The hemolytic uremic syndrome.

HUS is the most common cause of acute renal failure in infants and young children and follows a diarrheal prodrome about 90% of the time. Persuasive evidence shows that virtually all of postdiarrheal cases are caused by EHEC infections, and that the great majority of cases in the United States are caused by the EHEC serotype O157:H7. Mortality is approximately 5%, and approximately 10% of survivors are left with severe sequelae. A much larger number (30%-50%) experience mild chronic renal damage. Public health strategies, including zero tolerance for fecal contamination in slaughter houses and additional public education on proper food handling and cooking, does much to decrease the prevalence of the syndrome. Efforts to further dissect the postdiarrheal pathogenic cascade should continue, and an animal model needs to be developed. Only then will researchers be positioned to develop effective intervention strategies. Preventing life-threatening extrarenal complications, especially of the CNS, is a major challenge. Idiopathic nondiarrheal HUS accounts for approximately 10% of cases and comprises a poorly understood composite of HUS subsets. Research directed toward a better understanding of these mysterious variants also is a priority for the years ahead.

Diagnostic indices of zinc deficiency in children with renal diseases.

Abnormal taste acuity and zinc depletion have been reported with endstage renal disease. In order to determine when altered taste and zinc deficiency begin in the course of chronic progressive renal disease and to assess the various indices of zinc depletion, 14 pediatric patients were studied who were in various degrees of renal failure. They were not yet on dialysis or in need of transplantation. Taste acuity was abnormal in all patients. The mean plasma zinc levels were less than normal, but the differences were not statistically significant. The hair and RBC zinc concentrations, however, were significantly depressed. Analysis of the data indicate that zinc deficiency begins early in the course of chronic renal failure, that hair and RBC zinc measurements are the most reliable indicators of zinc status, and that poor intake of zinc containing foods is the major cause of the zinc depletion.

Hemolytic uremic syndrome in children.

The majority of postdiarrheal hemolytic uremic syndrome is caused by Escherichia coli O157:H7. The organisms are carried in the intestines of cattle; partially cooked contaminated hamburger is the single most common vector. The E. coli produce a potent cytotoxin that gains access to the circulation, is taken up by glycolipid receptors on glomerular endothelial cells, is internalized, and causes cell death. Associated phenomena include the activation of platelets, leukocytes, and the coagulation cascade, as well as the production of cytokines. Although some patients experience a mild or incomplete syndrome, life-threatening multisystem involvement can occur. Treatment is supportive, but plasma exchange may be useful in selected high-risk subsets. Efforts to prevent colitis from evolving into hemolytic uremic syndrome include the oral administration of material to bind the toxin in the gut. Mortality remains at 5% to 10%; about 4% are left with end-stage renal failure, and approximately 50% suffer mild chronic kidney damage.

The hemolytic-uremic syndrome.

Our experience with 61 episodes of the hemolytic-uremic syndrome in 60 patients showed a mean patient age of 3 years and a higher incidence of the disease during the summer months. Diarrhea, often bloody, preceded the other features of the illness in 93 percent of the cases. Hemolytic anemia, hematuria and proteinuria occurred in all of the patients. Thrombocytopenia and severe azotemia (blood urea nitrogen greater than 100 mg per dl) occurred in 74 percent and 72 percent of the children, respectively. Blood transfusions were necessary in 64 percent and dialysis was required in 54 percent of the cases. Mortality was low (5 percent) and 85 percent of the children had a complete recovery.

CT demonstration of cortical nephrocalcinosis in congenital oxalosis.

The clinical, pathologic and roentgenographic features of a case of congenital oxalosis are discussed and contrasted to the more common forms of primary oxalosis. The ease of demonstration of the cortical deposition of calcium oxalate crystals on the CT scanner is reported.

CNS manifestations of the hemolytic-uremic syndrome. Relationship to metabolic alterations and prognosis.

To define the CNS manifestations of the hemolytic-uremic syndrome (HUS), the records of 61 consecutive episodes of HUS in 60 patients were reviewed. Major CNS signs (seizures and/or coma) occurred in 30 of the 61 episodes. Twenty-four children had seizures. Analysis of blood pressure and metabolic parameters or admission to the hospital did not predict which child would exhibit CNS signs. However, during the subsequent course of the illness, children with CNS dysfunction had lower minimum serum sodium concentrations and more severe azotemia and were more likely to require dialysis than children without CNS signs. Of the 61 episodes, there were three deaths, and three children suffered major CNS sequelae. Coma at the time of admission and elevated CSF protein levels were features associated with poor outcome.