Absent intestinal response to calciferols in hereditary resistance to 1,25-dihydroxyvitamin D: documentation and effective therapy with high dose intravenous calcium infusions.

We describe a patient with an absent intestinal response to 1,25-dihydroxyvitamin D [1,25-(OH)2D] and the beneficial effects of treatment with high dose iv calcium infusion. The patient presented with severe rickets despite therapy with extraordinarily high doses of 1 alpha-hydroxyvitamin D3 or 1,25-(OH)2D3. Unidirectional intestinal fractional calcium absorption when he was not treated with any calciferol was 14% (normal, 20-70%), as measured with stable calcium isotopes; no increase in calcium absorption occurred when serum 1,25-(OH)2D levels were more than 50-fold elevated. Cultured skin fibroblasts contained no detectable 25-hydroxyvitamin D3-24-hydroxylase activity in response to 1,25-(OH)2D3 (10(-9)-10(-6) mol/L). High dose iv calcium infusions and oral phosphorus supplementation for 135 days improved or normalized biochemical parameters and resulted in radiographic healing of the rachitic lesions. We conclude that 1) this patient had no response to 1,25-(OH)2D3 in vivo and in vitro; 2) long term parenteral calcium infusions were effective therapy in managing the patient's severe resistance to 1,25-(OH)2D; and 3) stable calcium isotopes are useful for measuring low levels of fractional calcium absorption.

Increased incidence of insulin-dependent diabetes mellitus in pediatric renal transplant patients receiving tacrolimus (FK506)

BACKGROUND: Use of tacrolimus (FK506), a potent immunosuppressive agent, has been reported to have a 10-20% incidence of insulin-dependent diabetes mellitus (IDDM) in adults, but the incidence of IDDM in pediatric renal transplant recipients treated with this agent is unknown. In this article, we report our single-center experience with FK506-induced IDDM in children. METHODS: Five consecutive living related donor pediatric renal transplants were reviewed retrospectively. RESULTS: All five patients developed IDDM lasting longer than 6 months. Mean follow-up time was 18.6 months. CONCLUSIONS: Pediatric patients may be at high risk for developing FK506-induced IDDM.

Regression of dense deposits in Type II membranoproliferative glomerulonephritis: case report of clinical course in a child.

The clinical course and follow-up of a child who presented with rapidly progressive renal failure due to dense deposit disease is described. The patient showed a dramatic response to immunosuppressive and anticoagulent therapy. Two and a half years later, a follow-up renal biopsy showed regression of the intramembranous dense deposits on electron microscopy. The unusually slow progression of renal failure in this patient has been of interest and its possible relationship with either the disappearance of dense deposits or the initial therapy received are discussed.

The implementation of a continuous quality improvement program in a pediatric peritoneal dialysis unit.

Continuous quality improvement (CQI) principles and practices were utilized to evaluate the outpatient peritoneal dialysis follow-up process and the routine monthly laboratory testing of chronic dialysis patients. CQI enabled us to reduce total clinic visit time from a mean of 161 min to 90.8 min. Waiting was decreased from a mean of 51.6 min to 15.8 min. The number of routine monthly laboratory tests performed on patients undergoing chronic dialysis was also reduced, resulting in decreased charges of at least $429.50 per patient per month.

Cavitating pulmonary infarction in nephrotic syndrome.

A 6-year-old boy was admitted with anasarca due to relapse of nephrotic syndrome, non-productive cough, and dyspnea on exertion. On the 8th hospital day he manifested severe right shoulder and chest pain. A nodular opacity in the right lung that transformed into a cavitating lesion was documented by computerized axial tomography. Surgical biopsy of the affected area of the lung documented infarction due to pulmonary embolism. This case highlights the need to consider pulmonary embolism in the evaluation of nephrotic children with a cavitating pulmonary lesion.

Gentamicin-induced Bartter-like syndrome.

Gentamicin is well known to be associated with nephrotoxicity, including acute renal failure and renal tubular dysfunction. A Bartter-like syndrome has also been described as a toxic manifestation of gentamicin therapy in adults, but this nephrotoxic syndrome has not been well characterized in children. In this report we describe the clinical course of four patients with gentamicin-associated Bartter-like syndrome. These patients ranged in age from 4 months to 17 years; they all demonstrated evidence of renal tubulopathy, primarily affecting the distal nephron. Hypocalcemia, hypomagnesemia, alkalosis, and hypokalemia were the main manifestations in these patients. After discontinuation of gentamicin, recovery of the renal tubular functions and resolution of the electrolyte abnormalities were complete in all patients.

Anion gap in nephrotic syndrome.

Low anion gap occurs in a variety of disorders including hypoproteinemia. We evaluated anion gap in 28 children - 18 boys and 10 girls with minimal change nephrotic syndrome during 55 separate episodes of exacerbations. To assess the contribution of serum total proteins, albumin, cholesterol and immunoglobulin levels to low anion gap, a coefficient of correlation was calculated. Anion gap was significantly low (p less than 0.01) during exacerbations in nephrotic. The low anion gap correlated with low serum total proteins (less than 4 g/dl) and serum albumin levels (less than 1.5 g/dl) but not to serum cholesterol or immunoglobulin levels. Low total serum protein at patients blood pH, contributed fewer negative charges to anion gap thereby lowering the anion gap. The major cause of low anion gap in nephrotic syndrome is hypoproteinemia especially hypoalbuminemia.

IgA nephropathy (Berger's disease) - a clinicopathologic study in children.

Clinicopathologic features and follow up of 21 children with IgA nephropathy (Berger's disease) is discussed. The disease predominantly affected males. Although no definite prediction for any age group was observed, a majority (71.5%) of patient were six years or older. Macroscopic hematuria was the presenting feature in 71.5%, while as 28.5% had microscopic hematuria. Isolated proteinuria was not observed in any. 81% of the patients continue to have recurrent episodes of macroscopic hematuria, and 76% of the patients have microscopic hematuria during the symptom free intervals. Hypertension, azotemia and nephrotic syndrome were absent in all patients at the time of onset of the disease, and have not developed in any patient during follow up (mean 5.4 yrs). Serum IgA level elevated in only one (7.7%) of the thirteen patients in whom this was tested, and did not appear to be a diagnostic test of IgA nephropathy in children. The histologic features of renal biopsy did not correlate with known duration of the disease, extent of proteinuria at the time of biopsy or the degree of IgA deposits in the renal tissues. During childhood. IgA nephropathy appears to have an excellent prognosis, but longterm outlook can be projected only by following these children into adulthood.

Stenosing ureteritis in Henoch-Schönlein purpura.

We report on a boy with Henoch-Schönlein purpura in whom flank pain and gross hematuria developed during the early phase of the disease. Urologic investigations revealed hydronephrosis and ureteral stenosis. Pyeloplasty was done to relieve ureteropelvic junction obstruction. Severe hemorrhagic ureteritis and vasculitis were noted on the ureteral biopsy. Recovery was slow and residual hydronephrosis persisted. Although abdominal pain usually accompanies Henoch-Schönlein purpura, colicky flank pain associated with hematuria should alert the physician to the presence of ureteritis. Recognition and early surgical treatment of this urologic complication of Henoch-Schönlein purpura may prevent a potentially serious outcome.

End-stage renal disease in two pediatric patients with Fechtner syndrome.

Fechtner syndrome, a disease in the spectrum of the hereditary nephridites, is a macrothrombocytopenia associated with sensorineural hearing loss, cataracts, nephritis, and characteristic leukocyte inclusions. Renal biopsy findings are consistent with those of Alport syndrome, and the associated renal disease is said to be unusual before mid to late adulthood. Here, we review the available literature on this disease and report two African-American pediatric patients with Fechtner syndrome who rapidly progressed to end-stage renal disease during adolescence. We conclude that chronic renal failure can occur at a young age in patients with Fechtner syndrome, with a possible relation to race/ethnicity. Fechtner syndrome, or other variants of Alport syndrome, need to be considered in patients presenting with proteinuria and thrombocytopenia.