No abstract

Systemic vasculitic syndromes are rare in childhood. Vasculitis is the predominant feature of a large number of different clinical entities that are linked by the presence of inflammatory changes in the blood vessels. The nature of these diseases and their relationship to each other remain unclear. The clinical presentation associated with the size of the affected vessels and epidemiological data are very helpful for the diagnosis of those diseases. Recent advances are beginning to shed some light on the etiology and pathogenetic mechanisms involved in the various vasculitides. There is good evidence to support roles for circulating immune complexes, cell-mediated immunity, anti-neutrophil cytoplasmic antibodies and anti-endothelial cell antibodies in the pathogenesis. Renal involvement in vasculitis in children is commonly seen in Henoch-Schönlein purpura, microscopic polyarteritis, Wegener's granulomatosis, Churg-Strauss syndrome and polyarteritis nodosa. However, kidney disease can also be part of the clinical picture of Kawasaki disease and Takayasu arteritis. Recently, with the institution of early and aggressive immunosuppressive treatment of severe cases, significant improvement in the long-term survival of patients has been achieved. This review article addresses the pathological and clinical features (particularly renal involvement), therapeutic intervention and prognosis of the above-mentioned diseases.

NC, with renal failure secondary to bilateral dysplastic kidneys, received an LRD renal transplant (tx) at 17 months of age. Her early post-tx course was complicated by persistently elevated blood polyoma BK virus DNA loads. A protocol biopsy at six months post-transplant revealed BKVAN. Blood viral loads did not respond to decreased immunosuppression or treatment with ciprofloxacin and leflunomide. Six months post-tx, her serum creatinine began to rise and we sought experimental therapy to prevent the loss of her graft. At seven months post-tx, with FDA approval under an eIND, the patient was started on a 36-wk course of treatment with the investigational drug. The patient is now more than 24 months after stopping treatment with CMX. BKV viral DNA loads remain at low, but still detectable levels. Urine viral loads have declined, but remain elevated. EBV DNA loads become undetectable. The patient's serum creatinine has declined back to a baseline of 0.5-0.7 mg/dL and has been stable for two yr. Renal function was preserved in association with the use of CMX001 to treat BKV nephropathy in a young pediatric kidney transplant recipient. There were no serious adverse events associated with the use of CMX001. This novel medication may be of value in the treatment of BKVAN in pediatric renal transplant recipients.

Mycophenolate mofetil (MMF) is a new immunosuppressive drug used in combination with cyclosporin A (CsA) or tacrolimus and prednisone to prevent rejection of renal allografts in both adult and pediatric recipients. It has been shown in several large studies that MMF significantly decreases the incidence of acute rejection in adults and has acceptable adverse effects. In this retrospective study, we compare the incidence of adverse events between pediatric and adult renal allograft recipients. Twenty-two children and 37 adult renal allograft recipients were included in the study. The initial dose of MMF was 1.5 g b.i.d. for the adult patients and ranged from 15 to 30 mg/kg/d for the pediatric patients. All patients received p.o. acyclovir as prophylaxis for cytomegalovirus (CMV). The two groups were similar regarding gender distribution and graft source. Acute rejections occurred in 10 of the 22 pediatric patients (45%) and in nine of the 37 adults (24%), p = NS. The incidence of infections was similar in both groups except for the occurrence of CMV (n = 5), which was seen only in adults. The incidence of GI symptoms was significantly higher in the pediatric population (54.5% vs. 21.6%; p = 0.02). Significant weight loss was seen more often in the smaller pediatric patients (weight < or = 15 kg) compared to the larger pediatric patients, 60% vs. 11.7%, p = 0.05. Among the patients who had significant GI symptoms 50% of the adults and 75% of the pediatric recipients required either dose reduction or, most commonly, discontinuation of the MMF. The need to discontinue MMF was significantly higher in the pediatric patients, especially in those that weighed less than 15 kg. We suggest the possibility that the optimum dose, dosing interval or preparation of MMF has not yet been established for pediatric patients. One should therefore monitor pediatric patients closely, especially the small ones, to avoid significant nutritional problems and other adverse GI events.