Disease outcomes and ovarian function of childhood-onset systemic lupus erythematosus

The objective of this study was to determine the medical outcomes including the ovarian function childhood-onset SLE (cSLE). The medical records of all patients diagnosed with cSLE in the Greater Cincinnati area between 1981 and 2002 were reviewed. Patient interviews were performed to obtain additional information on current medication regimens, disease activity [SLE Disease Activity Index (SLEDAI-2k)], and damage [Systemic Lupus International Collaborating Clinics/American College of Rheumatology Damage Index (SDI)]. The occurence of premature ovarian failure (POF) and reduction of the ovarian reserve was assessed by timed gonadotropin levels. There were 77 patients (F: M = 70: 7, 53% Caucasian, 45% African-American and 2% Asian) with a mean age at diagnosis of 14.6 years. Nine patients died (88.3% survival) during the mean follow-up of 7.1 years (standard deviation [SD] 5.6) and 88% of the patients continued to have active disease (SLEDAI-2k mean/SD: 6.6/6.7), with 42% of them having disease damage (SDI mean/SD: 1.62/2.1); Non-Caucasian patients had higher disease activity (mean SLEDAI-2k: 10 versus 3.4; P < 0.0001) and more disease damage (mean SDI: 2.1 versus 1.2; P < 0.02) than Caucasian patients. Cyclophosphamide was given to 47% of the patients during the course of their disease and associated with the presence of significantly reduced ovarian reserve (RR = 2.8; 95% CI: 1.7-4.8; P = 0.026). Patient mortality and disease damage with cSLE continue to be high. Although overt POF with cyclophosphamide exposure is rare, it is a risk factor for significantly decreased ovarian reserve cSLE.

Acquired renal cysts after pediatric liver transplantation: association with cyclosporine and renal dysfunction

ACKD has been observed in children on dialysis and with chronic renal insufficiency. In one report, ACKD was observed in 30% of pediatric liver transplant recipients after 10 yr. We retrospectively reviewed all renal imaging and measurements of GFR of 235 childhood liver transplant recipients with no known risk for renal cyst formation, no evidence of renal cyst(s) at the time of transplantation and renal imaging at least one yr post-transplant. Twenty-six patients (11%) developed one or more cyst(s). Mean GFR was significantly lower in patients with renal cyst(s). Two (1.4%) of the 146 patients treated with tacrolimus and 24 (27%) of the 89 patients treated with CsA acquired renal cyst(s) (p < 0.001). CsA-treated patients had significantly lower GFR. Multivariate analysis identified CsA as the only independent variable associated with ACKD. These results confirm that ACKD can be a late complication of pediatric liver transplantation. Those at most risk are at least 10-yr post-liver transplantation, have been treated with CsA and have impaired renal function. We speculate that ACKD in these patients is the result of calcineurin inhibitor nephrotoxicity. Whether patients with ACKD will be prone to develop solid renal tumors is unknown.

Changes in left ventricular mass index in children and adolescents after renal transplantation

Recent reports indicate a high prevalence of left ventricular hypertrophy (LVH) in children on dialysis and after renal transplantation (Tx), as identified by cross-sectional analysis. However, the evolution of LVH in pediatric patients with end-stage renal disease after renal Tx is not well established. To assess changes of left ventricular mass (LVM), we prospectively performed echocardiography in 23 children and adolescents between November 1998 and July 2000. Each patient had an echocardiographic evaluation while on dialysis (for at least 6 weeks) and a follow-up evaluation at least 6 months after successful renal Tx (i.e. with a measured glomerular filtration rate [GFR] of at least 40 mL/min/1.73 m2). The LVM index was estimated by indexing LVM to height(2.7). Sixteen patients had a cadaveric transplant and seven had a live donor transplant; the mean duration between the two studies was 1.9 +/- 1.6 yr; and the mean GFR was 55.0 +/- 21.4 mL/min/1.73 m2. There was no significant difference in the mean values of the LVM index while on dialysis and after renal Tx (43.9 +/- 17.8 g/m2.7 and 39.3 +/- 12.0 g/m2.7, respectively, p = 0.19), or in the prevalence of LVH (52% and 56%, respectively). Interval changes in the LVM index in individual subjects between the two studies were significantly associated with interval changes in indexed systolic (r = 0.42, p = 0.04) and diastolic (r = 0.42, p = 0.05) blood pressures. Interval changes in hemoglobin, blood urea nitrogen (BUN), creatinine, and duration after Tx did not correlate with changes in the LVM index. There was no significant difference in LVM index change according to the type of dialysis, donor source, and the cause of renal failure. In multivariate analysis, the baseline LVM index and changes in indexed SBP were independent predictors for LVM index change after renal Tx. We conclude that LVH persists in children and adolescents after renal Tx. Control of blood pressure might be an important factor in regression or prevention of progression of LVH in these patients.

Changes in left ventricular mass in children and adolescents during chronic dialysis

Left ventricular hypertrophy (LVH) is an independent risk factor for cardiac mortality in adults with end-stage renal disease (ESRD). It is prevalent in pediatric patients on chronic dialysis. The objectives of this study were to evaluate left ventricular mass (LVM) in children and adolescents at the initiation of dialysis and to assess its changes during chronic dialysis therapy. In this longitudinal analysis, 29 patients aged 4-18 years had an echocardiographic evaluation within 90 days of starting dialysis therapy and a follow-up study at least 6 months later. LVH was defined as LVM index (g/m2.7) > 95th percentile for normal children and adolescents. On the initial echocardiogram 20 of 29 (69%) patients had LVH and 24 patients (83%) had abnormal LV geometry (38% eccentric LVH, 31% concentric LVH, and 14% concentric remodelling). Patients with LVH were more likely to be on antihypertensive medications (16/20) than patients without LVH (3/9) (P = 0.005). Repeat echocardiogram, performed after 10 +/- 3 months on chronic dialysis, showed no significant difference in the mean LVM index (49.6 +/- 17.5 g/m2.7 and 49.7 +/- 16.1 g/m2.7, respectively) or in the prevalence of LVH or LV geometric pattern. However, 14 of 29 patients had a progressive increase in LVM index and 15 patients had regression. Multiple regression analysis showed that baseline LVM index (P = 0.005) and interval change in indexed systolic blood pressure (P = 0.027) were independent predictors for LVM index changes. In summary, LVH and abnormal LV geometry are already prevalent in children and adolescents with renal failure at the time of initiation of dialysis therapy, indicating that LVH develops during the pre-ESRD course. Early intervention to control blood pressure may be an important factor to improve and prevent progression of LVH in pediatric patients with ESRD.

Severe left ventricular hypertrophy in pediatric dialysis: prevalence and predictors

Left ventricular hypertrophy (LVH) has been recognized as an independent risk factor for cardiovascular morbidity and mortality in adults with end-stage renal disease. However, the prevalence and severity of LVH in children on chronic dialysis therapy is not well established. Retrospectively, 64 chronic dialysis patients, aged 20 months to 22 years, on chronic dialysis had echocardiographic evaluation of LV mass (LVM) and geometry. Forty-eight (75%) children had LVH, including 22 of 26 (85%) on hemodialysis (HD) and 26 of 38 (68%) on peritoneal dialysis (PD). The prevalence of LVH in patients on HD was significantly higher than those on PD (P=0.02). Abnormal LV geometry was found in 51 of 64 (80%) patients: 25 patients (39%) had eccentric hypertrophy, 3 (5%) had concentric remodelling, and 23 (36%) had concentric LVH. Twenty-six children (41%) had severe LVH, defined as LVM index greater than 51 g/m2.7, which is associated with a fourfold greater risk for development of cardiovascular disease in adults. Patients with severe LVH had a significantly lower hemoglobin level (P=0.027) and longer duration of renal disease prior to the start of dialysis therapy (P=0.003) than patients without LVH. Multiple logistic regression analysis revealed HD as opposed to PD as a significant independent predictor for severe LVH (P=0.036). Higher systolic blood pressure remained in the final model as an independent predictor with a borderline level of significance (P=0.065). The results indicate that severe LVH and abnormal left ventricular geometry are common in young dialysis patients. Better control of blood pressure, anemia, and hypervolemia may be important in prevention or improving LVH.

Differences between membranoproliferative glomerulonephritis types I and III in long-term response to an alternate-day prednisone regimen

Membranoproliferative glomerulonephritis (MPGN) is classified as type I, II, or III based on ultrastructural alterations in the glomerular basement membrane. Whereas type II has long been recognized as clinically and pathologically unique, types I and III are often difficult to distinguish and have not been separated in most clinical studies. We compared the course and long-term outcome of patients with types I and III MPGN followed up at this institution since 1960. During this period, 21 patients with type I and 25 patients with type III were followed up for a minimum of 5 years. Patients with types I and III MPGN did not differ in age at apparent onset, age at diagnosis, or interval from apparent onset of symptoms to diagnosis (biopsy). They had similar initial serum C3 and serum albumin levels. Patients with type I had a significantly lower initial mean estimated glomerular filtration rate (GFR(est)) compared with those with type III (99.1 +/- 35.9 versus 131.6 +/- 36. 1 mL/min/1.73 m(2); P < 0.01). Type and duration of therapy, length of follow-up, and frequency of complications of therapy did not differ between groups. There was, however, a significant difference in duration of hypocomplementemia. After 1 year of an alternate-day prednisone regimen, 90% of the type I patients normalized their serum C3 levels compared with less than 50% of type III patients (P < 0.01). After 3 years of therapy, only 5% of type I patients were hypocomplementemic compared with 33% of type III patients (P < 0.02). In addition, disease relapse occurred in six type III patients (24%) compared with no type I patients. At last follow-up, type I patients had a slight improvement in mean GFR(est) (+6.3 +/- 48.4 mL/min/1.73 m(2)), whereas type III patients had a 25% decrease in mean GFR(est) (-34.8 +/- 47.6 mL/min/1.73 m(2); P < 0.01). Residual urinary abnormalities were significantly more frequent in patients with type III than type I MPGN. Hematuria persisted in 72% versus 38% (P < 0.05) and proteinuria in 28% versus 0% (P < 0.01) of those with types III and I, respectively. These results give clear evidence of significant differences in the clinical progression of the two types and their response to the alternate-day prednisone regimen. Whereas the outcome of patients with type I MPGN treated with alternate-day prednisone was generally good, similarly treated patients with type III experienced significant reductions in renal function, slower improvement in serum C3 levels, more persistent urinary abnormalities, and more frequent relapses.

Evaluation of perioperative antibiotics at the time of dialysis catheter placement

The effect of prophylactic antibiotics on the occurrence of peritonitis in the 14 days following surgical peritoneal dialysis catheter placement was evaluated. Medical records from 73 pediatric patients who had 89 Tenckhoff catheters inserted over 6 years were reviewed. Twelve catheter procedures were excluded for rapid catheter loss, unavailable charts, eosinophilic peritonitis, and antibiotic administration > 3 h postoperatively. Chi-squared analysis for non-continuous variables compared factors at the time of catheter placement with outcome (peritonitis). Thirteen patients developed postoperative peritonitis when 77 catheter insertions were analyzed (17%). Peritonitis was significantly more common in patients who did not receive perioperative antibiotics (7 of 16 catheter placements) (chi(2) = 12.48, P < or = 0.001). The reduced incidence of peritonitis was not specific to any one antibiotic class. Using step-wise logistic regression analysis, no association was found between peritonitis incidence and nephrotic syndrome, immunosuppression, recent surgery (< 14 days), acute versus chronic use, year of catheter placement, surgeon, or patient age. Catheter type, implantation technique, exit site care, and operative wound care did not vary. These results indicate that perioperative peritonitis episodes can be significantly reduced by the use of prophylactic antibiotics prior to or at the time of surgery.

Infantile hypophosphatasia: treatment options to control hypercalcemia, hypercalciuria, and chronic bone demineralization

A 2-month-old child with infantile hypophosphatasia had hypercalcemia (3.49 mmol/L (14 mg/dl)), nephrocalcinosis, and diminished bone mineral content. Hypercalcemia was corrected with calcitonin. Hypercalciuria and bone demineralization abated with chlorothiazide. Hypercalcemia is hypothesized to be related to normal bone resorption in conjunction with impaired bone mineralization. Chlorothiazide may alleviate this impairment.

Nutritional intake in children with renal insufficiency: a report of the growth failure in children with renal diseases study

OBJECTIVE

This study was designed to assess sequentially the nutrient intake in children with chronic renal insufficiency and its relationship to body size, the level of renal failure, and growth velocity.

METHODS

The nutrient intake from 401 4-day food records obtained from 120 children with renal insufficiency over a 6-month observation period was analyzed. The height and weight were measured at the beginning and end of the observation period. The glomerular filtration rate was estimated from the height and serum creatinine.

RESULTS

The mean caloric intake in these children was 80 +/- 23% (mean +/- SD) of the Recommended Dietary Allowance (RDA) for age. Fifty-six percent of the food records obtained from these children revealed a caloric intake that was less than 80% of the RDA. Caloric intake expressed as the %RDA for age decreased with increasing age. However, the mean caloric intake when factored by body weight was in the normal range. There was no correlation between caloric intake and height velocity. The mean protein intake in these children was 153 +/- 53% of the RDA. Further, 45% of the food records indicated a protein intake greater than 150% of the RDA. There was no relationship between the degree of renal insufficiency and caloric or protein intake. Calcium, vitamin, and zinc intakes were also low.

CONCLUSIONS

Children with chronic renal failure consume less calories than their age matched peers, but the majority of these children appear to ingest adequate amounts for their body mass. This reduction in caloric intake occurs early in renal insufficiency. They also ingest inadequate amounts of calcium, zinc, vitamin B6, and folate.

Discordant renal histopathologic findings and complement profiles in membranoproliferative glomerulonephritis type III

Patients with membranoproliferative glomerulonephritis (MPGN) type III and a low serum C3 concentration tend to have evidence for a nephritic factor of the terminal complement pathway (Nft). Complement profiles were studied in three patients with MPGN type III and low serum C3 concentrations. Serum C3 concentrations were 52, 21, and 14 mg/dL (normal range, 83 to 177 mg/dL). Serum Clq, C2, C4, properdin, and C5 concentrations were normal in all patients, whereas two had a slight decrease of C7 or C8. This pattern of complement activation resembles that seen with MPGN type II in which a nephritic factor activates the amplification loop (NFa). We conclude that in patients with MPGN type III the previously reported profile/presence of Nft is not always found, at least in the chronic stage of the disease, despite a low C3 value.

Effect of growth hormone on urine calcium and serum vitamin D metabolites in renal failure

Growth hormone (GH) causes a modest increase in urine calcium excretion in normal adults, but uremic rats given both GH and calcitriol developed hypercalciuria. Ten short prepubertal children with renal insufficiency treated with recombinant human GH (rhGH) had urine calcium to creatinine (Ca/Cr) ratios and serum vitamin D metabolite concentrations monitored prospectively for up to 24 months. Six were also treated with calcitriol and two with other vitamin D preparations. Mean urine Ca/Cr ratios or mean serum concentrations of 1,25-dihydroxy vitamin D, 24,25-dihydroxy vitamin D, and 25-hydroxy vitamin D did not change significantly during treatment with rhGH. The risk for rhGH-induced hypercalciuria is small in children with renal insufficiency, even when treated concomitantly with a vitamin D preparation.

Nutritional management of the child with mild to moderate chronic renal failure

1. The best way to prevent early growth failure in children with renal disease is by the use of specified nutrition and appropriate buffer, activated vitamin D, and calcium-containing phosphate binders as needed. With prenatal diagnosis of anatomically abnormal kidneys available, this type of early intervention may be much more feasible in the 1990s. 2. Supplemental sodium and water in children with polyuria and intravascular volume depletion may prevent growth failure. Cow milk is detrimental in this group of individuals because of high solute and protein load, often causing intravascular volume depletion, hyperphosphatemia, and acidosis. 3. Children with acquired glomerular disease may need sodium restriction and, if treated with steroids, a diet low in saturated fat. 4. Children with nephrotic syndrome and severe edema should be evaluated for malabsorption and subsequent malnutrition. Protein intake should be supplemented only at the RDA and to replace ongoing losses. Long-term sodium restriction is appropriate. Hyperlipidemia should be monitored: if nephrosis is chronic, a low saturated fat diet should be instituted. Angiotensin-converting enzyme inhibitors can decrease urinary protein loss and may ameliorate hyperlipidemia. Children resistant to therapy can have very high morbidity. 5. Children with <50 % of normal creatinine clearance should have PTH measured and activated vitamin D therapy should be started if PTH is elevated more than two to three times normal. Thereafter careful monitoring of calcium, phosphorus, and PTH is crucial to prevent renal osteodystrophy, low turnover bone disease, and hypercalcemia with hypercalciuria and nephrocalcinosis. 6. Children with tubular defects with severe polyuria also may benefit from low-solute, high-volume feedings. 7. All physicians caring for children with renal disease should have pediatric nephrology consultation available. Prevention of growth failure is much more cost effective than pharmacologic therapy. Before initiating growth hormone treatment for growth retardation, assiduous treatment of co-existing renal osteodystrophy and provision of optimal nutritional intake should be accomplished.

Serum complement levels before and after the onset of acute post-streptococcal glomerulonephritis. A case report

Low serum C3, properdin, and C5 levels found in the acute stage of acute post-streptococcal glomerulonephritis (APSGN) indicate the presence of aggressive complement activation. We followed serum complement component levels in a child hospitalized with erysipelas who developed APSGN on the 2nd hospital day. Her initial serum sample, obtained prior to the clinical onset of nephritis, had a low properdin level and normal C3 and C5 levels despite the presence of C3 splitting activity. Two days later she developed gross hematuria and subsequent sera contained low C3, properdin, and C5 levels, as is usual in APSGN. These observations suggest that complement activation, predominantly through the alternative pathway, precedes the clinical onset of APSGN.

A prospective, double-blind study of growth failure in children with chronic renal insufficiency and the effectiveness of treatment with calcitriol versus dihydrotachysterol. The Growth Failure in Children with Renal Diseases Investigators

Because controlled trials in adults have shown accelerated deterioration of renal function in a small number of patients receiving calcitriol for renal osteodystrophy, we initiated a prospective, randomized, double-blind study of the use of calcitriol versus dihydrotachysterol in children with chronic renal insufficiency. We studied children aged 1 1/2 through 10 years, with a calculated glomerular filtration rate between 20 and 75 ml/min per 1.73 m2, and with elevated serum parathyroid hormone concentrations. Ninety-four patients completed a mean of 8.0 months of control observations and were randomly assigned to a treatment period; 82 completed the treatment period of at least 6 months while receiving a calcitriol dosage (mean +/- SD) of 17.1 +/- 5.9 ng/kg per day or a dihydrotachysterol dosage of 13.8 +/- 3.3 micrograms/kg per day. With treatment the height z scores for both calcitriol- and dihydrotachysterol-treated groups showed no differences between the two groups. In relation to cumulative dose, there was a significant decrease in glomerular filtration rate for both calcitriol and dihydrotachysterol; for calcitriol the rate of decline was significantly steeper (p = 0.0026). The treatment groups did not differ significantly with respect to the incidence of hypercalcemia (serum calcium concentration > 2.7 mmol/L (> 11 mg/dl)). We conclude that careful follow-up of renal function is mandatory during the use of either calcitriol or dihydrotachysterol because both agents were associated with significant declines in renal function. There was no significant difference between calcitriol and dihydrotachysterol in promoting linear growth or causing hypercalcemia in children with chronic renal insufficiency. Dihydrotachysterol, the less costly agent, can be used with equal efficacy.

Activated C3 (C3b) in the nephritic glomerulus

An autoradiographic technique was developed to assess in the nephritic glomerulus the relative amount of C3 which is in the activated form, C3b, compared with the inactivated form, iC3b. Frozen renal biopsy sections from children and young adults with glomerulonephritis were assessed for the C3b fraction of total C3, using a radiolabeled monoclonal anti-C3c. Grain counts with this antibody, before and after reacting the section with 0.0002% trypsin, gave the relative amounts of total C3 and C3b, respectively. C3b was found in all diseases studied. To explain its presence, glomerular C3b acceptors which would restrict C3b inactivation were sought by immunofluorescence studies. C3b acceptor candidates were: IgG in aggregated form, IgA as found in the IgA nephropathies and the C3/C5 convertase, C4b,2a,3b. In acute post-streptococcal glomerulonephritis and membranoproliferative glomerulonephritis type III, diseases in which these acceptors were lacking, it is postulated that the nephritis strain-associated protein and absence of membrane cofactor protein, respectively, may be responsible for C3b deposition. The phlogistic effect of C3b is mediated largely by one of its products, C5b-9. However, the C3b: total C3 ratio failed to correlate with indices of glomerular inflammation, probably in part because the ratio is not a measure of total glomerular C3b.

Distribution and correlates of creatinine clearance in children and adolescents with blood pressure elevation

The kidney has been implicated as both an etiologic factor and as a target organ in patients with essential hypertension. Renal function has not been studied extensively in children and adolescents with essential hypertension. Eighty-eight subjects, aged 6 to 23 years, with blood pressure persistently above the 90th percentile for age were studied. Creatinine clearance was determined from a single 24-hour urine collection. The mean creatinine clearance was 129.3 +/- 55.3 ml/min per 1.73 m2. Multiple regression analysis was used to investigate potential correlates of creatinine clearance. Because creatinine clearance was not normally distributed, the logarithm of creatinine clearance was used as the dependent variable. Body mass index, resting heart rate, and basal supine plasma renin activity were significant direct independent correlates. Peripheral vascular resistance at maximal exercise was an inverse correlate of the logarithm of creatinine clearance. These findings are consistent with previous studies of adults and may provide the basis for strategies to identify young patients with essential hypertension who are at risk for the development of renal dysfunction.

Multicystic dysplastic kidney in children: US follow-up

Eighty-one cases of multicystic dysplastic kidney (MCDK) in children were diagnosed over the past 11 years at the authors' institution: 25 children had their kidneys surgically removed, eight with bilateral total involvement died, and 48 underwent serial follow-up ultrasonography (US) of their kidneys. Follow-up included 193 serial ultrasound (US) studies (mean, four per patient) for a total of 1,468 months (mean, 30.5 months). In the 48 patients followed up, 32 (67%) kidneys showed a decrease in size, nine (19%) showed no change, and five (10%) increased in size, and in two (4%), a change in size could not be determined. In seven of the 48 (15%) children, the MCDKs decreased in size, and, at follow-up US, no renal tissue could be found. In those patients in whom MCDKs decreased in size. Serial US characteristics changed from predominantly an enlarged cystic structure to a small dysplastic or absent kidney. Two of the five kidneys that increased in size were surgically removed, and MCDK was pathologically confirmed. A nonsurgical approach to the treatment of patients with MCDK is supported by this study.

Urine-to-blood carbon dioxide tension gradient and maximal depression of urinary pH to distinguish rate-dependent from classic distal renal tubular acidosis in children

We determined the prevalence and clinical features of rate-dependent distal renal tubular acidosis (dRTA) in 31 children examined for possible renal tubular acidosis by measuring the urinary-minus-blood partial pressure of carbon dioxide (U-B PCO2) gradient, minimal urinary pH, and fractional excretion of bicarbonate. Of 20 patients with low U-B PCO2 gradients, nine could not lower urinary pH < or = 5.5, indicating classic dRTA, whereas 11 could lower urinary pH < or = 5.5, as described in rate-dependent dRTA. When patients with rate-dependent dRTA and classic (type I) dRTA were compared, there was no difference in the mean U-B PCO2 gradient or in clinical findings, including age, reason for referral, presence of nephrocalcinosis, or depression of linear growth. We conclude that children with rate-dependent dRTA are susceptible to at least some of the same sequelae as children with classic dRTA. Measurement of minimal urinary pH will not detect this subtle form of dRTA. Determination of the U-B PCO2 gradient should be considered a routine part of evaluation for suspected renal tubular acidosis in a child.

Long-term follow-up of non-systemic lupus erythematosus glomerulonephritis in patients with hereditary angioedema: report of four cases

Hereditary angioedema (HAE) is characterized by a deficiency in C1 inhibitor protein (C1 INH) and by clinical symptoms of episodic swelling of subcutaneous or mucosal tissue. It has rarely been reported in association with non-systemic lupus erythematosus (SLE) glomerulonephritis (GN). A recent report of two cases indicates the prognosis to be poor, with both patients progressing to chronic renal failure 8 and 20 years after diagnosis. This report describes the 5-year follow-up of a previously unreported case of an 8-year-old boy with HAE and non-SLE membranoproliferative glomerulonephritis (MPGN). The patient developed macroscopic hematuria, azotemia, and a vasculitic rash. Treatment included prednisone and cyclophosphamide, resulting in clinical improvement. The present report also summarizes the long-term follow-up of three previously reported cases of HAE and non-SLE GN, 25, 16, and 10 years after their initial presentation. Patients monitored for 25 and 16 years had MPGN and normal renal function and received no therapy. The third patient, monitored for 10 years, had segmental MPGN. This patient presented with urinary abnormalities and, after treatment with prednisone, had improvement in her hematuria. None of these four patients developed chronic renal failure. These observations indicate a variable outcome in patients with HAE and non-SLE GN.

IgG subclass restriction of autoantibody to solid-phase C1q in membranoproliferative and lupus glomerulonephritis

The IgG subclass distribution for autoantibodies to solid-phase C1q (anti-spC1q) in sera from 14 patients with membranoproliferative glomerulonephritis (MPGN) and 10 patients with systemic lupus erythematosus (SLE) nephritis was determined by an enzyme-linked immunosorbant assay employing C1q as the immunosorbant in the presence of 2 M NaCl to prevent Fc binding and monoclonal anti-human IgG subclass reagents. The autoantibody to spC1q in MPGN, especially in types I (7 patients) and II (3 patients), was almost entirely restricted to IgG3. In contrast, in SLE anti-spC1q was completely restricted to IgG2 in 3 patients while predominantly IgG2 in the other 7 patients. The different subclass restriction of anti-spC1q in these two disorders suggests that antibody formation is either in response to different epitopes on the collagen-like region of C1q or that patients with SLE and MPGN mount different immunologic responses to the same antigenic stimulus.

Rapid improvement in the renal tubular dysfunction associated with tyrosinemia following hepatic replacement

The postoperative management of patients with hereditary tyrosinemia type I (McKusick 27670) following liver transplantation is often complicated by the renal tubular dysfunction associated with this disease. To characterize better the temporal course of the improvement in renal excretory activity following hepatic replacement, renal tubular function and metabolite excretion were studied in a 4-year-old girl with hereditary tyrosinemia during the immediate post-transplantation course. Tubular reabsorption of bicarbonate and phosphate were normal 5 days following transplantation, in contrast to glucosuria, hyperaminoaciduria, and tyrosyluria, which persisted for approximately 3 weeks. After hepatic replacement, serum amino acid concentrations returned to normal and succinylacetone was no longer detected in the urine. This is the third tyrosinemia patient reported to achieve complete resolution of urinary abnormalities following transplantation, and the only patient in whom renal tubular function was formally assessed within the first postoperative week.

Acquired structural genitourinary abnormalities contributing to deterioration of renal function in older patients with nephropathic cystinosis

The natural progression of nephropathic cystinosis to end stage renal disease can be delayed, sometimes by many years, by the reducing agent, cysteamine, which lowers intracellular cystine content to near normal. We report on two patients with nephropathic cystinosis who were treated with cysteamine and developed structural genitourinary abnormalities which may have contributed to an increase in the rate of decline of renal function. One patient, aged 11 years, was found to have massive megacystis and hydroureteronephrosis but no anatomic bladder outlet obstruction. His abnormality was presumed to be related to chronic high urine volumes leading to megacystis and physiologic ureteral obstruction. Vesicostomy stabilized renal function. The second patient, aged 11 1/2 years, was found to have bilateral renal cystic disease which presumably was acquired and may have been related to long-standing hypokalemia. Minor renal abnormalities were found by ultrasound in five additional cystinotic children. We concluded that older children with nephropathic cystinosis may be prone to acquire structural abnormalities of their kidneys or urinary tract.

Hyperechoic renal medullary pyramids in infants and children

Fifty-five children (34 boys, 21 girls; age range, 1 day to 18 years) with increased echogenicity of the renal medullary pyramids at ultrasound evaluation were identified. The clinical diagnoses associated with hyperechoic medullary pyramids could be separated based on the presence or absence of hypercalciuria. Patients with drug-induced hypercalciuria included 10 infants treated with furosemide, two treated with long-term steroid therapy, and one treated with excessive amounts of vitamin D. Other clinical conditions associated with hypercalciuria included renal tubular acidosis (n = 10), Bartter syndrome (n = 5), hyperparathyroidism (n = 3), Williams syndrome (n = 2) and medullary sponge kidney (n = 2). Ten children with transient renal insufficiency and three with sickle cell disease had normal urine calcium concentration. Isolated disease entities accounted for the remainder of cases. A specific diagnosis can usually be made in a patient with hyperechoic renal medullary pyramids by using a systematic clinical approach that includes evaluation of patient age, serum and urine calcium concentration, and renal function.

Continuous hemodiafiltration in children

Continuous arteriovenous hemofiltration is a form of renal replacement therapy whereby small molecular weight solutes and water are removed from the blood via convection, alleviating fluid overload and, to a degree, azotemia. It has been used in many adults and several children. However, in patients with multisystem organ dysfunction and acute renal failure, continuous arteriovenous hemofiltration alone may not be sufficient for control of azotemia; intermittent hemodialysis or peritoneal dialysis may be undesirable in such unstable patients. Recently, the technique of continuous arteriovenous hemodiafiltration has been used in many severely ill adults. We have used continuous arteriovenous hemodiafiltration in four patients at Children's Hospital Medical Center. Patient 1 suffered perinatal asphyxia and oliguria while on extracorporeal membrane oxygenation. Patients 2 and 4 both had Burkitt lymphoma and tumor lysis syndrome. Patient 3 had septic shock several months after a bone marrow transplant. All had acute renal failure and contraindications to hemodialysis or peritoneal dialysis. A blood pump was used in three of the four patients, while spontaneous arterial flow was adequate in one. Continuous arteriovenous hemodiafiltration was performed for varying lengths of time, from 11 hours to 7 days. No patient had worsening of cardiovascular status or required increased pressor support during continuous arteriovenous hemodiafiltration. The two survivors (patients 2 and 4) eventually recovered normal renal function. Continuous arteriovenous hemodiafiltration is a safe and effective means of renal replacement therapy in the critically ill child. It may be ideal for control of the metabolic and electrolyte abnormalities of the tumor lysis syndrome.

Autoantibody to complement neoantigens in membranoproliferative glomerulonephritis

With the exception of C3 nephritic factor, autoantibody formation has not been commonly associated with membranoproliferative nephritis (MPGN). We measured autoantibodies (nephritic factors) to the C3 convertases C3bBb (NFa) and C3bBbP (NFt), which result in fast and slow C3 activation, respectively, and to a neoantigen on C1q fixed to a solid phase (spC1q) in sera from 29 patients with MPGN type I, 26 with type II, and 28 with type III. Autoantibody formation was common in all MPGN types. An autoantibody to a C3 convertase neoantigen was identified in more than 75% of the hypocomplementemic MPGN sera tested. Anti-C3bBb (NFa) was present in 81% of patients with MPGN type II but was rarely found in either type I or type III. Anti-C3bBbP (NFt) was common in both MPGN I and III. Anti-spC1q was present in 74% of patients with type I and in 38% and 48% of types II and III MPGN, respectively. Patients with MPGN types I, II, and III had one and two serum autoantibodies detected significantly more frequently than did a group of healthy subjects. The presence of any one autoantibody was not specifically associated with the presence of any other autoantibody. The results indicate that multiple autoantibody formation is common in all MPGN types. MPGN II, and possibly MPGN I, tend to form more specific autoantibodies.

Distribution of target-organ abnormalities by race and sex in children with essential hypertension

The prevalence of left ventricular hypertrophy, glomerular hyperfiltration and retinovascular abnormalities was investigated in 43 black and 45 white children with essential hypertension. Whilst 36% of subjects had left ventricular hypertrophy, 49% had glomerular hyperfiltration and 50% had retinal abnormalities, no differences were found between blacks and whites. This pattern differs from that found in adult hypertensives.

A properdin dependent nephritic factor slowly activating C3, C5, and C9 in membranoproliferative glomerulonephritis, types I and III

The IgG fraction of serum from patients with membranoproliferative glomerulonephritis (MPGN) types I and III was found to contain a nephritic factor (NFI/III) which differed from that usually present in MPGN type II and partial lipodystrophy (NFII) in that it converts C5 and C9 as well as C3, is dependent on properdin for its activity, and requires an incubation period of several hours rather than 30 min for its demonstration. C3 conversion occurred in the absence of an intact classical pathway. This nephritic factor was found in patients with reduced serum levels of terminal components and its activity, like that of the nephritic factor in MPGN type II, correlated with the serum C3 level indicating that these nephritic factors play a large role in producing hypocomplementemia. Although potentially nephritogenic because of its ability to activate the terminal pathway, the presence of this nephritic factor did not clearly correlate with clinical course.

Serum terminal complement component levels in hypocomplementemic glomerulonephritides

Measurements of serum C3 through C9 are reported for patients with acute poststreptococcal glomerulonephritis (AGN), membranoproliferative glomerulonephritis type I (MPGN I), MPGN II, and MPGN III. Except in MPGN II, depressed C5 levels correlated with depressed C3 levels. In MPGN II, levels of C5 and of other terminal components were normal. In MPGN III, markedly depressed levels of C7 through C9 correlated strongly with depressed levels of C3 and C5. C6 was less severely depressed. In MPGN I, terminal component levels were less often depressed than in MPGN III and in AGN, depression of terminal components was seen only when levels of C3 and C5 were extremely low. The data indicate that late terminal components are activated in MPGN III to a greater extent than in the other nephritides despite C5 activation approximately equal in extent to that in AGN and MPGN I.

Antibody to a cryptic, solid phase C1Q antigen in membranoproliferative nephritis

IgG containing material detected in membranoproliferative nephritis (MPGN) serum with a solid phase (sp) Clq ELISA has been presumed to be immune complexes. However, in serum from 13 MPGN patients containing large amounts of spClq-binding material, sucrose density ultracentrifugation and sieve chromatography showed spClq-binding protein to sediment at 7S or cofractionate with IgG. One serum (stored for 12 years) contained, in addition, spClq-binding material sedimenting at more than 19S. Isolated MPGN IgG was shown to bind to spClq. SpClq-binding material could be totally removed from MPGN serum by absorption with BSA-anti-BSA immune precipitates, and by acid elution of the precipitates IgG binding to spClq could be recovered. F(ab')2, isolated from pepsin digested MPGN IgG, continued to bind spClq. Binding of MPGN IgG or F(ab')2 to spClq was not inhibited by 2 M NaCl. Incubation of MPGN serum with 125I Clq followed by sucrose density ultracentrifugation resulted in a peak of radioactivity at 11S, the sedimentation rate of Clq, giving evidence that material binding fluid phase Clq is not present. SpClq-binding IgG was detected in 54% of 68 MPGN patients. These results indicate that the 7S spClq-binding IgG represents antibody to a cryptic antigen revealed only when Clq fixes to a solid surface.

Effect of calcitonin replacement therapy in idiopathic juvenile osteoporosis

An 8-year-old boy with idiopathic juvenile osteoporosis and multiple fractures had three abnormalities of bone mineral metabolism: calcitonin deficiency, elevated serum calcitriol concentrations, and hypercalciuria. Calcitonin deficiency was documented by two attempts to stimulate calcitonin secretion with intravenous calcium and pentagastrin. Treatment for 11 months with daily subcutaneous injections of human calcitonin and oral administration of calcitriol failed to reduce the excessive bone resorption observed on bone biopsy, and the fracture rate did not decrease. Treatment was discontinued for two months, then resumed with calcitonin injections and oral calcium supplementation. The fracture rate decreased but bone biopsy continued to show excessive resorption. Therapy was discontinued. After the onset of puberty, endogenous calcitonin was detectable. Exogenous calcitonin therapy may have failed to control bone resorption for several reasons: insufficient dose, reduction of bone receptors from long-term calcitonin exposure, secondary hyperparathyroidism, or lack of association between calcitonin deficiency and the bone disease.

Differences between membranoproliferative glomerulonephritis types I and III in clinical presentation, glomerular morphology, and complement perturbation

Data for 26 patients with membranoproliferative glomerulonephritis, type I (MPGN I) and 22 with membranoproliferative glomerulonephritis, type III (MPGN III), as distinguished by glomerular ultrastructure, were analyzed to determine differences in presentation, complement perturbation, and glomerular morphology by light microscopy. MPGN III was detected with greater frequency by the chance discovery of hematuria and proteinuria in the otherwise healthy individual (MPGN III, 63%; MPGN I, 30%; P = .01) and never, in the absence of renal failure, presented with systemic symptoms such as ease of fatigue, weight loss, and pallor, as may patients with MPGN I. The more frequent detection of MPGN III by chance is evidence that its onset is insidious and that for long periods it produces no symptoms or signs. Glomerular proliferation is also less than in MPGN I. Further, in MPGN III, the complement perturbation and glomerular immunofluorescence give no evidence of classical pathway activation, for which there is abundant evidence in MPGN I. Even with severe hypocomplementemia in MPGN III, C3 nephritic factor, another cause of hypocomplementemia, is rarely detectable and then in very low concentration. The cause of the complement perturbation in MPGN III has so far escaped identification. Although these observations give evidence that MPGN III is distinct from MPGN I, there is compelling evidence from other studies that a predisposition to both types is inherited and that similar genetic factors are operative in the two types. Because their genetic basis appears to be the same, it must be concluded that despite their differences, types I and III are variants of the same disease.

Minoxidil for control of acute blood pressure elevation in chronically hypertensive children

Twenty-three episodes of acute elevation of BP related to renal disease in 13 chronically hypertensive children 2 to 18 years of age were treated with a single oral dose of minoxidil. All except one patient were receiving a diuretic and all but one a beta-blocking agent at the time of minoxidil treatment. The goal of lowering BP to or below the 95th percentile for age within four hours of minoxidil administration was achieved in 14 of 23 treatment episodes. The goal was achieved in nine of 11 (82%) when the dose of minoxidil was greater than or equal to 0.2 mg/kg and in five of 12 (42%) when the dose was less than 0.2 mg/kg (P less than .05). In patients treated with greater than or equal to 0.2 mg/kg of minoxidil, mean systolic and diastolic BP decreased significantly from pretreatment values within one hour. In patients receiving less than 0.2 mg/kg, mean systolic BP was never significantly reduced and mean diastolic BP did not change significantly for two hours. Adverse effects were minimal. The results indicate that minoxidil in a dose of 0.2 mg/kg in combination with a diuretic and beta-blocking agent will lower BP to safe levels in most patients with severe hypertension related to renal disease within four hours with minimal side effects.

Effect of the nephrotic syndrome on the concentration of serum complement components

The concentration of 12 component and four control proteins of the complement system was measured in serum from 43 children with a nephrotic syndrome, which subsequently proved to be steroid-responsive, and from 13 children with focal glomerulosclerosis (FGS) and was compared with values from 197 normal subjects. Of classical pathway complement components, 40% of patients had low C1q levels and 20%, low C2 levels. Mean serum levels of C1s, C4, C1INH, and C4bp were elevated. Of alternative pathway components, factors B and I were low in one third, while levels of C3 and H were commonly elevated. Of the terminal components, only C8 and C9 were low. In five patients with FGS with hypoalbuminemia without edema, all component levels were normal. With the exception of C1q, C1s, and C8, high molecular weight (mol wt) components were in high concentration and low mol wt components in low concentration. The three exceptions may be explained by the subunit structure of C1 and C8. From a practical standpoint, the study indicates that edematous patients with a nephrotic syndrome may have low serum levels of C1q and C2, simulating classical pathway complement activation such as commonly occurs in glomerulonephritis. However, low levels of C4, and possibly C1s, can be used as indicators of classical pathway activation since their levels are not reduced by a nephrotic syndrome.

Improved growth of three uremic children by nocturnal nasogastric feedings

Three children with high-output renal insufficiency (estimated creatinine clearance, 20 to 25 mL/min/1.73 sq m) and linear and ponderal growth retardation were administered nocturnal nasogastric (NG) feedings at home by trained parents. The NG feedings were initiated at 50 kcal/kg/night and increased as needed to establish and maintain weight gain. Nocturnal feedings were continued for 13.5, 16, and 11 months, respectively. Improved caloric intake reestablished the velocity of weight gain from less than 5% to greater than 95% in each patient. Linear growth velocity improved from less than 5% in two patients and 40% in one patient to greater than 95% in two patients and 80% in the third patient. No change was observed in serum creatinine, electrolyte, calcium, or phosphorus levels. The serum urea nitrogen level remained below 100 mg/dl. Ensuring adequate caloric intake by nocturnal NG feedings, in addition to standard therapy, improved both ponderal and linear growth velocity.

Atypical hypocomplementemic vasculitis syndrome in a child

We report a patient who developed recurrent urticaria and angioedema at age 2 years, severe hypocomplementemic glomerulonephritis at 11 years, and end-stage renal disease at 14 years. His disease resembled the hypocomplementemic vasculitis syndrome but was atypical in its early age of presentation, severe hypocomplementemia, and progression to end-stage renal disease. Serum C1q levels were extremely low, and C4, C2, C3, and C5 levels were significantly reduced. Serum C1 inhibitor (C1INH) levels were slightly low, presumably from consumption. Circulating C1INH-C1r-C1s complexes were evidenced by reduced ratios of functional to antigenic C1INH and antigenic C1r to C1s. Family members had normal functional and antigenic levels of all complement components studied. The patient's serum, erythrocytes, platelets, and mononuclear cells did not activate complement when mixed with normal target serum. Absence of a circulating complement activator and the low serum C3 and C5 levels suggested the presence of a solid-phase complement activator, possibly related to renal or systemic vascular endothelium. As in patients with homozygous deficiencies of classical pathway components, a severe, prolonged, acquired C1q deficiency may have predisposed this patient to the development of glomerulonephritis.

Reduction of phagocyte adherence by nephritic sera: relation to complement activation

Phagocytes isolated from either normal donors or from patients with poststreptococcal (P-SGN), lupus erythematosus (SLE-GN), or membranoproliferative (MPGN) glomerulonephritis showed normal adherence to glass (PAg) after incubation in normal human serum (NHS), but was reduced after incubation in patient serum. Low PAg was the consequence of incubation of normal phagocytes with the earliest available sera from all 22 P-SGN patients, 28 of 37 SLE-GN patients, 19 of 25 patients with MPGN type I, all 10 with types II and III, and all 5 with nephritis associated with chronic bacteremia. Low C3 and decreased PAg were related by regression analysis in sera from patients with P-SGN (P less than 0.001), SLE-GN (P less than 0.005), and MPGN (P less than 0.001) type I. In patients with P-SGN and one patient with nephritis associated with chronic bacteremia, complement levels and PAg returned to normal in parallel with clinical improvement. In vitro, PAg was reduced by NHS treated with either zymosan or bovine serum albumin (BSA)-anti-BSA complexes but neither BSA-anti-BSA complexes or zymosan, previously incubated in NHS, reduced PAg. PAg was normal in serum deficient in C4 or C5 unless treated with zymosan.

Type III membranoproliferative glomerulonephritis: long-term clinical and morphologic evaluation

Seventeen patients with Type III membranoproliferative glomerulonephritis (MPGN) have been followed for more than two years; 16 were treated with alternate day prednisone. Clinical deterioration correlated with nephrotic syndrome (NS) at diagnosis: 3 of 7 patients with NS at diagnosis developed end-stage disease. Serial biopsies in the others showed progressive disease in one, improvement in one and no change in two. Of 10 patients without NS at diagnosis, 6 have improved clinically, 2 are unchanged and 2 are worse. In serial biopsies, 6 showed improved morphology and 4 were unchanged. The results indicate that Type III MPGN will stabilize or improve in most treated patients. The absence of ultrastructural transition of a Type III glomerular lesion to another type and the presence of distinctive immunofluorescent findings and complement abnormalities confirm that Type III is a unique form of MPGN.

Membranoproliferative glomerulonephritis and alpha 1-antitrypsin deficiency in children

Two white girls had reduced serum concentration of alpha 1-antitrypsin (alpha-AT), phenotype ZZ, and liver disease. Hepatocytes exhibited the microscopic criteria of alpha-AT deficiency. Hypocomplementemia, elevated circulating immune complexes (patient 1), clinical signs of renal disease, and the histologic findings of membranoproliferative glomerulonephritis (MPGN) type I developed. Immunoglobulin A (but not alpha-AT) was demonstrable immunologically as a component of glomerular deposits in patient 1. Among 53 patients with MPGN but without clinical signs of liver disease, none had Pi type Z. Among 23 patients with phenotype ZZ but without clinical signs of kidney disease, six had abnormal complement protein levels, but the pattern did not resemble that of idiopathic MPGN type I. These results are consistent with the conclusion that MPGN in the two patients reported here is a consequence of their chronic liver disease and is not directly related to the presence of the allelic alpha-AT variant PiZ.

Nonabsorptive hydrocephalus associated with nephropathic cystinosis

A child with nephropathic cystinosis developed seizures and coma. CT showed prominent sulci and slight ventricular enlargement. Nuclear cisternogram was normal. Despite successful renal transplantation and treatment of hypothyroidism, neurologic recovery was poor. CT and nuclear cisternogram 5 months later showed moderate panventricular and subarachnoid space enlargement and abnormal ventricular isotope retention. Ventriculoperitoneal shunt placement was followed by improved intellectual function, resolution of pyramidal tract signs, and control of seizures. Anisotropic crystals consistent with cystine were demonstrated in biopsy samples of arachnoid and cerebral cortex. Nonabsorptive hydrocephalus may have resulted from deposition of cystine in the meninges.

Membranoproliferative glomerulonephritis characterized by focal, segmental proliferative lesions

Of 61 children with membranoproliferative glomerulonephritis (MPGN), 6 (10%) were distinguished by segmental lesions in up to 1/3 of glomeruli. Light microscopy showed mild to moderate generalized mesangial proliferation in addition to segmental membranoproliferative lesions. Mesangial fluorescence with antiserum to C3 was present in all glomeruli while focal lesions were characterized by segmental granular fluorescence with antiserum to IgG. Segmental lesions, identified by electron microscopy in four biopsies, were produced by prominent mesangial proliferation. Subendothelial deposits were present in two. Contiguous subendothelial and subepithelial deposits were present in one, and in a fourth, capillary wall deposits could not be found although mesangial deposits were present. Circulating immune complexes were present in 2 of the 4 hypocomplementemic patients and 1 normocomplementemic patient. Clinically, all patients presented with hematuria (gross in 3) and five had proteinuria. Only one had hypoalbuminemia. All patients have improved (5 treated with alternate day prednisone) as judged by the return of complement levels to normal and by improvement in urinalysis and in glomerular morphology on subsequent biopsy. The results give evidence that focal, segmental MPGN is an early manifestation of Type 1 or, uncommonly, Type III MPGN and that the patients have an excellent prognosis.

Hypocomplementemia in Reye syndrome: relationship to disease stage, circulating immune complexes, and C3b amplification loop protein synthesis

Measurement of C1q, C2, C4, C5, C6, factor B, properdin, beta1H, and C3bINA were made in acute sera from 31 patients with Reye syndrome. Abnormalities were found in 18 patients. The magnitude of the complement component depression correlated with disease severity. Sera from patients with stage IV illness had significantly lower complement levels than did sera from patients with state I (P less than 0.001), II (P less than 0.05), and III (P less than 0.05) disease. Circulating immune complex measurements were performed on all 31 acute sera and were present in six (19%). However, from the results of the present study, it would appear that in the majority of the patients circulating immune complexes are not the cause of the lowered levels of, at least, C3 and factor B. Rather, these low levels could be explained as secondary to reductions in the levels of the C3b amplification loop control proteins beta1H and C3bINA.

Experience with a low volume ultrafiltration cell in small children*

A low volume (16 ml) ultrafiltration cell was used ten times in two small, fluid overloaded children to remove plasma water. The device was simple to use and, at slow blood flow rates (25-50 ml/minutes) and low transmembrane pressures (10-30 mm Hg), provided controlled removal of excess fluid. Although no major complications were encountered, hypothermia and hypotension (at ultrafiltrate flux rates exceeding 0.5 ml/kg/minute) were observed. The ultrafiltrate solute concentration was similar to plasma and no significant shifts in serum electrolytes were induced. The ultrafiltrate protein concentration of 64 to 2,760 mg/dl was much higher than previously reported.