Elaine S. Kamil

A Peripheral Blood Diagnostic Test for Acute Rejection in Renal Transplantation

Monitoring of renal graft status through peripheral blood (PB) rather than invasive biopsy is important as it will lessen the risk of infection and other stresses, while reducing the costs of rejection diagnosis. Blood gene biomarker panels were discovered by microarrays at a single center and subsequently validated and cross‐validated by QPCR in the NIH SNSO1 randomized study from 12 US pediatric transplant programs. A total of 367 unique human PB samples, each paired with a graft biopsy for centralized, blinded phenotype classification, were analyzed (115 acute rejection (AR), 180 stable and 72 other causes of graft injury). Of the differentially expressed genes by microarray, Q‐PCR analysis of a five gene‐set (DUSP1, PBEF1, PSEN1, MAPK9 and NKTR) classified AR with high accuracy. A logistic regression model was built on independent training‐set (n = 47) and validated on independent test‐set (n = 198)samples, discriminating AR from STA with 91% sensitivity and 94% specificity and AR from all other non‐AR phenotypes with 91% sensitivity and 90% specificity. The 5‐gene set can diagnose AR potentially avoiding the need for invasive renal biopsy. These data support the conduct of a prospective study to validate the clinical predictive utility of this diagnostic tool.

Complete Steroid Avoidance Is Effective and Safe in Children With Renal Transplants: A Multicenter Randomized Trial With Three‐Year Follow‐Up

To determine whether steroid avoidance in pediatric kidney transplantation is safe and efficacious, a randomized, multicenter trial was performed in 12 pediatric kidney transplant centers. One hundred thirty children receiving primary kidney transplants were randomized to steroid‐free (SF) or steroid‐based (SB) immunosuppression, with concomitant tacrolimus, mycophenolate and standard dose daclizumab (SB group) or extended dose daclizumab (SF group). Follow‐up was 3 years posttransplant. Standardized height Z‐score change after 3 years follow‐up was –0.99 ± 2.20 in SF versus –0.93 ± 1.11 in SB; p = 0.825. In subgroup analysis, recipients under 5 years of age showed improved linear growth with SF compared to SB treatment (change in standardized height Z‐score at 3 years –0.43 ± 1.15 vs. –1.07 ± 1.14; p = 0.019). There were no differences in the rates of biopsy‐proven acute rejection at 3 years after transplantation (16.7% in SF vs. 17.1% in SB; p = 0.94). Patient survival was 100% in both arms; graft survival was 95% in the SF and 90% in the SB arms (p = 0.30) at 3 years follow‐up. Over the 3 year follow‐up period, the SF group showed lower systolic BP (p = 0.017) and lower cholesterol levels (p = 0.034). In conclusion, complete steroid avoidance is safe and effective in unsensitized children receiving primary kidney transplants.

Treatment of Antineutrophil Cytoplasmic Autoantibody-Positive Systemic Vasculitis and Glomerulonephritis With Pooled Intravenous Gammaglobulin

Antineutrophil cytoplasmic autoantibody (ANCA) is considered a serological marker for disease activity in patients with ANCA(+) systemic vasculitis. Recently, ANCA has been implicated as a pathogenic antibody that may be associated with neutrophil degranulation and release of lytic enzymes. Since intravenous gammaglobulin (IVIG) is known to contain antiidiotypic antibodies to ANCA, which could decrease the activity of the later, we chose to treat two patients with symptomatic ANCA(+) systemic vasculitis and glomerulonephritis with high-dose IVIG. The first patient, a 66-year-old man, developed rapidly progressive renal failure despite treatment with intravenous (IV) cyclophosphamide. The second patient, a 14-year-old boy, had relapsed 3 months after cessation of treatment with prednisone and cyclophosphamide. Both patients improved dramatically after treatment with IVIG, with the former recovering renal function within 11 days of therapy. In both patients, a concomitant reduction in serum ANCA titers was also observed. The second patient is currently in a sustained remission 14 months after his last IVIG dose on no other medication. These cases provide clinical evidence that IVIG has therapeutic benefit in modifying the immune-mediated injury associated with ANCA(+) systemic vasculitis and glomerulonephritis. In addition, IVIG may provide an additional safe therapeutic option to clinicians treating patients with ANCA(+) vasculitis and glomerulonephritis who are not responsive to or are experiencing toxicity from conventional therapy.

Long-Term Cyclosporine A Treatment of Steroid-Resistant and Steroid-Dependent Nephrotic Syndrome

Eighteen patients with steroid-resistant nephrotic syndrome (SRNS) and steroid-dependent nephrotic syndrome (SDNS) were treated with cyclosporine A (CyA) (6 mg/kg/d) for 2 to 29 months. CyA levels were monitored monthly and plasma levels by Abbott TDX (Therapeutic Drug Analyzer System) fluorescence polarization immunoassay were maintained at 100 to 150 ng/mL. The corticosteroid dosage administered at the time CyA therapy was initiated was variable and was continued following CyA therapy. Six of these patients (all with SDNS and minimal change nephrotic syndrome [MCNS]) had been treated with one or more courses of cytotoxic drug therapy, and all had clinical evidence of corticosteroid toxicity after receiving corticosteroid therapy for 26 to 120 months. The corticosteroid dosage was reduced by slow tapering and was ultimately discontinued in six patients. These patients were maintained on CyA monotherapy for 7 to 21 months at a dose of 3.2 to 6.7 mg/kg/d. Following 11 to 29 months of CyA therapy, seven patients underwent an elective renal biopsy, which showed nephrotoxicity in all seven. This led to discontinuation of CyA in four patients. Following discontinuation of CyA monotherapy, all four patients relapsed within 2 to 4 months. CyA therapy did not achieve a remission in 10 patients with SRNS regardless of the presence of focal segmental glomerulosclerosis (FSGS) or MCNS on renal biopsy. In conclusion, CyA has limited effectiveness in patients with SDNS who manifest corticosteroid toxicity; however, CyA should be used cautiously because of the potential for CyA nephrotoxicity and the failure to obtain a sustained remission following discontinuation of CyA monotherapy. CyA dependence is substituted for corticosteroid dependence.

The Clinical Impact of Humoral Immunity in Pediatric Renal Transplantation

The development of anti-donor humoral responses after transplantation associates with higher risks for acute rejection and 1-year graft survival in adults, but the influence of humoral immunity on transplant outcomes in children is not well understood. Here, we studied the evolution of humoral immunity in low-risk pediatric patients during the first 2 years after renal transplantation. Using data from 130 pediatric renal transplant patients randomized to steroid-free (SF) or steroid-based (SB) immunosuppression in the NIH-SNSO1 trial, we correlated the presence of serum anti-HLA antibodies to donor HLA antigens (donor-specific antibodies) and serum MHC class 1-related chain A (MICA) antibody with both clinical outcomes and histology identified on protocol biopsies at 0, 6, 12, and 24 months. We detected de novo antibodies after transplant in 24% (23% of SF group and 25% of SB group), most often after the first year. Overall, 22% developed anti-HLA antibodies, of which 6% were donor-specific antibodies, and 6% developed anti-MICA antibody. Presence of these antibodies de novo associated with significantly higher risks for acute rejection (P=0.02), chronic graft injury (P=0.02), and decline in graft function (P=0.02). In summary, antibodies to HLA and MICA antigens appear in approximately 25% of unsensitized pediatric patients, placing them at greater risk for acute and chronic rejection with accelerated loss of graft function. Avoiding steroids does not seem to modify this incidence. Whether serial assessments of these antibodies after transplant could guide individual tailoring of immunosuppression requires additional study.

Nephrocalcinosis and renal cysts associated with apparent mineralocorticoid excess syndrome.

Abstract Apparent mineralocorticoid excess (AME) syndrome is a rare inherited disorder caused by 11β- hydroxysteroid dehydrogenase (11-HSD 2) isozyme deficiency in the kidney. This enzyme is responsible for oxidizing cortisol to its inactive metabolite cortisone. An elevated tetrahydrocortisol (THF) and allotetrahydrocortisol (aTHF) to tetrahydrocortisone (THE) ratio in the urine is pathognomonic of AME syndrome. Clinical features include hypertension, hypokalemia, alkalosis, reduced plasma renin activity (PRA), low aldosterone levels, and occasionally nephrocalcinosis. Here we describe a 13-year-old boy who presented with severe hypertension, hypokalemia, low PRA and aldosterone levels, and elevated THF plus aTHF/THE ratio in the urine consistent with a diagnosis of AME syndrome. On ultrasound examination, he had severe nephrocalcinosis, and bilateral renal cysts. Renal cysts have not been previously reported in AME syndrome. The development of nephrocalcinosis and renal cysts may be associated with chron-ic long-standing hypokalemia. An early diagnosis and treatment of AME syndrome could help to prevent these sequelae, and to preserve renal function.

Nephronophthisis associated with Ellis-van Creveld syndrome

Abstract. Ellis-van Creveld (EvC) and Jeune’s asphyxiating thoracic dystrophy (ATD) are related disorders characterized by narrow thoracic cage and short-limbed dwarfism. Some patients have overlapping features of both ATD and EvC, indicating that these syndromes may be a part of a disease spectrum. Nephronophthisis has been occasionally reported in patients with ATD, but not with EvC syndrome. We report a patient who was diagnosed with EvC syndrome at birth. He developed hypertension at 5 months of age and gradually progressive renal failure, requiring renal transplantation at 8 years. Histopathological findings in the nephrectomy specimen were indicative of nephronophthisis. The association of nephronophthisis in a patient with EvC syndrome has not been reported previously. This association further supports the hypothesis that ATD and EvC syndromes are related and represent a spectrum of disorders.

Protracted, gross hematuria in sickle cell trait: response to multiple doses of 1-desamino-8-D-arginine vasopressin

Gross and microscopic hematuria are well-known complications in patients with sickle cell hemoglobinopathy. Most of these episodes of gross hematuria are self limiting, but rarely may be severe and persistent requiring definitive intervention. Before subjecting these patients to surgical management such as partial or total nephrectomy, several medical therapies of variable benefit have been suggested. We report a patient with sickle cell trait who experienced severe, intractable gross hematuria for 5 months and showed a dramatic response to multiple doses of 1-desamino-8-D-arginine vasopressin (DDAVP) infusion. The remarkable response observed in this patient suggests that treatment with DDAVP infusion may be considered in patients with unremitting gross hematuria associated with sickle cell trait.

Preventing recurrence of focal segmental glomerulosclerosis following renal transplantation: A case report

Abstract:  While the recurrence of FSGS in a primary renal transplant has been well studied, strategies to prevent subsequent recurrence in later transplants, has not been well formulated. This is important considering that one centers experience with adults reported an initial recurrence rate of 57% with reoccurrence of 37% in subsequent transplants. However, renal function was maintained in 62% ( 1 ). In pediatrics, data from a single‐center reported 100% recurrence of FSGS in the second allograft after an initial recurrence of 52% ( 2 ). Two commentaries reviewing such data, one each in adults and pediatrics, suggested that the benefits of living‐related donation might not be realized in patients with FSGS because of this frequent recurrence ( 3, 4 ). Here, we report a patient who was considered to be at very high risk for post‐transplant recurrence of FSGS, because of the established risk factors, who was successfully retransplanted after a course of pretransplant plasmapheresis, followed by post‐transplant plasmapheresis and the use of cyclosporine. Eighteen months post‐transplant, he has no proteinuria and his serum creatinine is 1.2 mg/dL.

Treatment of Active Cytomegalovirus Disease with Oral Ganciclovir in Renal Allograft Recipients: Monitoring Efficacy with Quantitative Cytomegalovirus Polymerase Chain Reaction

Treatment regimens of patients with active cytomegalovirus (CMV) disease require 2–3 weeks of intravenous ganciclovir (GCV) with/without CMV hyperimmune globulin. Oral GCV is effective as a prophylactic agent in prevention of CMV disease. Here we explored the utility of oral GCV as a treatment of active CMV disease. Fifteen renal allograft recipients (CMV donor +/recipient –{53%}, CMV donor +/recipient + {40%} or CMV donor –/recipient + {7%}) developed active CMV disease. Cytomegalovirus polymerase chain reaction (CMV‐PCR) tests were performed at the time of presentation and patients were treated with oral ganciclovir 1 g tid (adjusted for renal function). Patients were monitored for efficacy of treatment by assessment of clinical symptoms and CMV‐PCR. Treatment was continued until the CMV‐PCR copy number was negative and symptoms resolved. The mean CMV‐PCR copy number at the time of diagnosis was 580 copies/μg DNA (nl: < 5 copies/μg DNA). After 5–7 days of treatment, the mean copy number was 65 copies/μg DNA. Fourteen of 15 patients responded well to oral ganciclovir, with complete resolution of clinical symptoms and eradication of CMV‐PCR positivity. One patient did not respond to oral ganciclovir therapy due to probable noncompliance. Our data suggest that oral ganciclovir treatment, coupled with careful CMV‐PCR monitoring, may be a reasonable alternative to long‐term intravenous ganciclovir.