Intravenous iron dextran and erythropoietin use in pediatric hemodialysis patients.

Recombinant human erythropoietin (rHuEPO) is an effective treatment for the anemia of chronic renal failure. However, adequate availability of iron is necessary for an optimal response. We prospectively evaluated the effect of an intravenous iron protocol in a pediatric hemodialysis unit. Patients with either a serum ferritin less than 150 ng/ml or transferrin saturation (TSAT) less than 20% received intravenous iron dextran during ten consecutive dialysis sessions. The administration of rHuEPO was adjusted using a protocol designed to maintain patient hematocrit between 33% and 36%. Thirteen courses of intravenous iron were evaluated. Patients received 4 mg/kg of iron dextran (maximum of 100 mg) during each of ten consecutive dialysis sessions. In 12 cases there was a decrease in rHuEPO use 2 months after completing the course of intravenous iron. The mean rHuEPO dose decreased from 3,784 units to 2,115 units (P<0.005). Based on the criteria of response to intravenous iron, a percentage iron saturation of less than 20% had a high specificity for detecting iron deficiency. All patients who received a course of intravenous iron had a TSAT less than 20%. The measurement of serum ferritin was less useful in our patients.

Pseudotumor cerebri with vision impairment in two children with renal transplantation.

The syndrome of pseudotumor cerebri consists of headaches, difficulty with vision and papilledema associated with raised intracranial pressure (ICP) without localizing neurological mass lesions. Recently, an association of pseudotumor cerebri and renal insufficiency, chronic dialysis or renal transplantation has been noted. Loss of vision remains a serious threat in children with pseudotumor cerebri. We report two children who developed pseudotumor cerebri with impairment of vision 5 years after renal transplantation. An awareness of this association should prompt the nephrologist to investigate and treat the symptoms of raised ICP to prevent visual loss.

Increased incidence of HLA-B40 group antigens in children with hemolytic-uremic syndrome.

Hemolytic uremic syndrome (HUS) develops in 25-30% of children infected with Escherichia coli strains that produce Shiga-like toxins, also known as verocytotoxins. Mild HUS also occurs in 1 in 4 of the other family members, suggesting a familial predisposition to HUS. To understand the possible genetic predisposition, the frequency of HLA antigens was evaluated in 30 children (12 boys, 18 girls; mean age 3.8 years) with HUS following a prodrome of bloody diarrhea. When compared to a blood donor population from the same geographic area and ethnic background, no significant differences were noted in the frequency of HLA-A, HLA-C, HLA-DR, and HLA-DQ antigens. However, the frequency of HLA-B40 and its splits (B60, 61, 41, 47) was significantly higher in the study population (corrected p < 0.005). The relative risk of developing HUS was 6.04 when HLA-B40 and HLA-B40 split products were present, and the risk increased to 8.5 when the analysis was extended to include the cross-reactive antigens B44 and B13. These HLA-B antigens share common amino acid sequences at positions 41-45 and 67-74 on the alpha-1 domain of the HLA class I molecule. Our data suggest that the inheritance of HLA-B40, its splits, and cross-reactive antigens increases the risk of developing HUS.

Outcome of renal transplantation in children aged 1-5 and 6-18 years.

Results of renal transplantation in younger children have not been very encouraging in the past. We therefore studied the effect of newer immunosuppressive regimens on the outcome of renal transplantation of 5 children aged 2.9 +/- 1.3 years (range 1.6-5.0), and compared it to 10 children of an older pediatric patient group aged 11.4 +/- 4.4 years (range 6.0-18.5). All patients with the exception of 1 underwent dialysis. The percentage of cadaveric and live-related transplants was similar in both groups. Recipients of a cadaveric transplant had at least 3 blood transfusions; recipients of live-related transplants had donor-specific transfusions with azathioprine. Posttransplantation immunosuppression consisted of prednisone and azathioprine; recipients of cadaveric transplants received also ciclosporin. Rejection episodes and side effects (hypertension, hirsutism) were comparable in both groups. In the younger patient group, 1 patient died of a congenital lung abnormality but had a functioning graft. In the older patient group, 1 patient lost his graft 16 months posttransplantation due to reduction of his immunosuppressives, necessitated by a severe CMV infection. Growth and development improved in the younger patient group, but was stable in older patients. Renal transplantation is a suitable option in younger pediatric patients. Graft survival rates are comparable to those of older patients.

Focal segmental glomerulosclerosis in desquamative interstitial pneumonia.

Renal involvement in desquamative interstitial pneumonitis (DIP) manifesting as chronic renal failure has been reported only once. An uncommon disorder in children, DIP has been associated with a variety of systemic disorders and has an immune-mediated pathogenesis. A 16-year-old Black male was diagnosed to have DIP on lung biopsy at the age of 10 months. He was first noted to have proteinuria at age 5 which progressed to nephrotic syndrome by age 13 when the laboratory tests showed elevated IgG, normal serum complement, increased circulating immune complexes and absent anti-GBM antibodies. A percutaneous renal biopsy specimen performed at age 13 revealed focal segmental glomerulosclerosis. Despite prednisone treatment of 2 mg/kg/day for 12 weeks, renal failure progressed requiring hemodialysis. Pulmonary functions, although reduced, remained stable.

Prediction of intra ocular lens power in 100 patients using the ophthasonic a scan unit.

The aim of this study was to determine the range of ametropias encountered by using the computerized Ophthasonic A-Scan. The SRK formula was used to compute the IOL power using axial length and keratometry as inputs. The accuracy of prediction of IOL power was calculated by noting the disparity between the expected post-operative refraction and the actual refraction obtained after one and a half months of IOL implantation. The results obtained were encouraging; the maximum deviation from the expected result being +/- 3.2 D.

Early diagnosis of Bardet-Biedl syndrome.

A 3-year-old boy presented with decreased renal function, hypertension, obesity and developmental delay. Evaluation of his kidneys revealed blunting of the calyces and multiple renal cortical cysts. Ophthalmologic evaluation showed no abnormalities on examination but electroretinography showed reduced retinal function suggesting a diffuse retinal disorder. Based on the clinical presentation with the associated abnormalities, the diagnosis of Bardet-Biedl syndrome, a form of the Laurence-Moon-Biedl syndrome was made. This syndrome should be considered and specific diagnostic efforts should be made in pediatric patients who present with renal failure and obesity.

Renal transplantation in a child with primary oxalosis.

Primary hyperoxaluria (oxalosis) is an autosomal recessive disorder due to an inherited deficiency of the peroxisomal alanine:glyoxylate aminotransferase characterized by increased production and urinary excretion of oxalate and glycolate resulting in renal failure due to oxalate deposition. Because of the risk of continuing oxalate deposition in the transplanted kidney, oxalosis had been considered a contraindication for transplantation. A 5-year-old boy with oxalosis, maintained on peritoneal dialysis, received a haploidentical qiving-related transplant. The preoperative management included donor-specific transfusions and daily hemodialysis to remove a maximum amount of oxalate. The immunosuppression consisted of azathioprine and prednisone. Aggressive fluid management including noncalciuric diuretics (hydrochlorothiazide) kept urine output high. Pyridoxine, magnesium, neutral phosphate and sodium benzoate were used to prevent deposition of oxalate in the transplanted kidney. Two acute rejection episodes responded to steroid boluses. A kidney biopsy during the second rejection episode confirmed the diagnosis but also revealed oxalate deposits in the transplanted kidney. More than 4 years after transplantation, the patient has catch-up growth and his serum creatinine is 1.4 mg/dl. In conclusion, oxalosis is not an absolute contraindication to renal transplantation. Transplantation can be performed successfully utilizing living-related donor kidneys and aggressive medical management. The risks of deterioration of function and oxalate deposition in the transplant kidney are offset by improvement in quality of life.

Shock in an infant with bullous mastocytosis.

A 6-month-old infant had bullous lesions on his posterior neck, upper trunk, and extremities for two months prior to admission for fever and shock. He had an elevated white blood cell count with left shift and normal platelet count, but abnormal coagulation studies. He was treated with intravenous antibiotics, crystalloids, fresh-frozen plasma, and pressor agents. A histamine H2 receptor antagonist was started for guaiac-positive nasogastric tube drainage. The patient recovered after four days of treatment. A skin biopsy confirmed mastocytosis. A week later the child passed grossly bloody stools with blood clots. No source of gastrointestinal bleeding was identified by extensive work-up. Blood histamine level measured one day before gastrointestinal bleeding was 16,400 pg/ml (normal 263 +/- 202 pg/ml). The bleeding resolved spontaneously. The patient was maintained on cimetidine. Results of a subsequent bone scan were normal. Shock or gastrointestinal bleeding associated with unusual skin lesions should alert the pediatrician to the possibility of mastocytosis.

Failure of fresh frozen plasma infusions to alter the course of hemolytic uremic syndrome.

The hemolytic uremic syndrome (HUS) is characterized by thrombocytopenia, anemia, and acute renal failure. Fresh frozen plasma (FFP) infusions have been claimed to shorten the course of HUS. However, no long-term follow-up is available. Hence, we analyzed the effects of FFP infusions on acute resolution and long-term sequelae of HUS in 12 children (5 boys, 7 girls, mean age 4.5 years, range 7 months to 9 years) and compared to a historical control group of 31 children (13 boys, 18 girls, mean age 3 years, range 8 months to 9 years). The patient population, severity of HUS, and other modes of therapy except FFP were similar in the two groups. There was no statistically significant difference between the groups in the acute resolution of HUS as evaluated by recovery of anemia, thrombocytopenia, and return of renal functions. Long-term sequelae of HUS such as hypertension, end-stage renal disease, and CNS residual abnormalities were also similar in two groups. One child died in the FFP group and 2 children died in the control group. We feel that FFP infusions have no significant effect on the course of HUS and its use should be questioned.

Reversal of central nervous system involvement in hemolytic uremic syndrome by use of plasma exchanges.

A 12-year-old girl presented with weakness, diplopia, and lethargy after a prodrome of gastroenteritis. Laboratory studies were compatible with a diagnosis of hemolytic uremic syndrome. She developed seizures that were controlled by diphenylhydantoin and valium. In spite of peritoneal dialysis and fresh frozen plasma infusions, she progressed to a left hemiplegia associated with a brain scan finding of decreased blood flow in the right middle cerebral artery perfusion area. A 5 liter whole blood exchange transfusion did not improve the neurological status or low platelet count. Daily plasma exchanges with fresh frozen plasma replacement resulted in normal platelet count within 48 hours and was followed by progressive improvement in neurological status. Platelet agglutinating factor decreased to control levels. A repeat brain scan was normal.

Neurological involvement in hemolytic-uremic syndrome.

Of 44 children with hemolytic-uremic syndrome seen at Milwaukee Children's Hospital, 15 (34%) had neurological involvement. This group contained 8 boys and 7 girls, with a mean age of 3 1/4 years. Twelve patients had seizure within 48 hours of admission. Seizures were associated with hypertension, fever, hyponatremia, or hypocalcemia. Other neurological symptoms included altered consciousness, behavioral changes, diplopia, and dizziness. Hemiparesis (4 patients), eye involvement (7 patients), decerebrate posturing (2 patients), and ataxia (1 patient) were present on physical examination. Cerebrospinal fluid examination showed increased protein in 4 of 11 patients. Electroencephalograms were abnormal in all 9 patients tested. Computed tomographic and radionuclide scans showed evidence of vascular abnormalities in 4 of the 14 patients studied. Complete neurological recovery occurred in only 6 of the 15 children, while the remaining 6 demonstrated residual hemiparesis, seizures, and cortical visual defect. In those children with neurological involvement, there was a higher incidence of residual hypertension (49% versus 11%), chronic renal damage (40% versus 3.5%), and death (28% versus 0%), suggesting that central nervous system involvement indicates severe hemolytic-uremic syndrome.

Hemolytic uremic syndrome associated with Corynebacterium diphtheria infection.

Although hemolytic uremic syndrome (HUS) is usually idiopathic, it follows a number of infections. The pathogenesis of post-infectious HUS is endothelial cell damage by either circulating endotoxin or exotoxin. Diphtheria exotoxin has never been implicated in HUS. We report HUS following diphtheria infection in a 9 yr old un-immunized white female admitted with a short history of sorethroat and thrombocytopenia. There were hemorrhages in sclera, gums and left tonsillar area and a grayish exudate on right tonsil. Laboratory values revealed Hgb 14.4 g/dl, decreasing to 7.6 g/dl, WBC/26,900 mm3, platelet count 7,000/mm3. Bone marrow examination revealed normal megakaryocytes. She was oliguric with BUN 214 mg/dl, serum creatinine 12.4 mg/dl and serum uric acid 19.2 mg/dl. Despite peritoneal dialysis, red cell and platelet transfusions and exchange transfusion she expired. A postmortem examination was refused. A throat culture done on admission grew corynebacterium species which was later confirmed to be toxigenic C. diphtheriae. Diphtheria exotoxin inactivates an enzyme in cytoplasm which is necessary for peptide chain elongation. This may have interfered with prostacyclin synthesis thereby allowing the development of HUS.

Cystic renal involvement in tuberous sclerosis.

We describe two cases of unusual presentation of tuberous sclerosis with cystic renal involvement. A 19-month-old white male who was initially misdiagnosed as having polycystic kidney disease of "adult-type" developed petit mal seizures and small "ash-leaf" depigmented areas, raising a suspicion of tuberous sclerosis. Computerized tomography (CT) of the brain revealed periventricular calcifications, confirming the diagnosis of tuberous sclerosis. A 15 3/4-year-old black female with tuberous sclerosis showed acceleration of renal failure. Computerized tomography scan of the abdomen showed cystic lesions of the kidneys. In young children with cystic renal involvement but a negative family history of tuberous sclerosis or polycystic kidney disease, a CT scan of the brain should assist in the diagnosis. A CT scan or ultrasound examination of the abdomen will differentiate cystic renal lesions from angiomyolipoma of the kidneys.

Myoglobinuria with acute renal failure and hot kidneys seen on bone imaging.

We report a case of myoglobinuria secondary to prolonged seizures. The child showed "hot kidneys" with bone scintigraphy. The disease entity and etiologies of nontraumatic rhabdomyolysis are discussed.