Conversion to Sirolimus in a Population of Kidney and Kidney-Pancreas Transplant Recipients

Conversion to sirolimus in kidney-pancreas and pancreas transplantation

Reports on the use of sirolimus (SRL) in pancreas transplantation are still limited. The aim of this study was to evaluate the outcome of SRL conversion in pancreas transplant patients. Among 247 patients undergoing simultaneous kidney-pancreas or solitary pancreas transplantation, 33 (13%) were converted to SRL. The reasons for conversion were calcineurin inhibitors (CNI) nephrotoxicity (n = 24; 73%), severe neurotoxicity owing to CNI (n = 1; 3%), severe and/or recurrent acute rejection episodes (n = 7; 21%), gastrointestinal (GI) side effects of mycophenolate mofetil (MMF; n = 5; 15%), and hyperglycemia (n = 4; 12%). Before conversion, all patients were maintained on a CNI, MMF, and low-dose steroids. They were gradually converted to SRL associated with either CNI or MMF withdrawal. Sixty-three percent (n = 15) of patients who were converted owing to CNI nephrotoxicity, showed stable or improved renal function. At 12 months after conversion, serum creatinine levels were significantly decreased in this group (2.2 +/- 0.5 vs 1.6 +/- 0.3 mg/dL; P = .001) and C-peptide values increased (2.9 +/- 1.1.1 vs 3.1 +/- 1.3 nmol/L; P = .018). The only patient with leucoencephalopathy showed improved neurologic status after SRL conversion. All patients converted to SRL because of GI side effects of MMF showed improvements, and none of those converted because of hyperglycemia experienced improvement. There were no episodes of acute rejection after conversion. We concluded that conversion to SRL in pancreas transplantation should be considered an important alternative strategy, particularly for CNI nephrotoxicity and neurotoxicity, and in cases of severe diarrhea due to MMF.

Assessment of risk factors for cardiovasuclar disease in pediatric renal transplant patients

Pediatric renal TP recipients are at risk for CVD. We performed a cross-sectional study of the prevalence of RF for CVD in 45 long-term pediatric renal TP patients. The time since TP was 42 months. The GFR was 87.8 +/- 3.4 mL/min/1.73 m(2); 25/45 (56%) had Stage 2-4 CKD. A total of 33% had elevated SBP and 24% had high DBP; 57% had elevated SBP or DBP. A total of 20% had elevated serum CHOL levels, while 45% had high serum TG levels. A total of 42% had high HCY levels and 50% had low HCT levels. The vast majority (66.7%) had at least two RF for CVD. A total of 18.2% had abnormal post-TP echocardiography results. There was a negative correlation between GFR and SBP, DBP, serum CHOL, HCY, and BMI. There was a positive correlation between GFR and HCT. Serum CHOL was significantly lower and SBP and DBP trended lower in patients on a SF immunosuppression regimen. Similarly, SBP and DBP trended higher and CHOL was significantly higher in patients receiving SRL vs. mycophenolate mofetil. We conclude that the majority of pediatric renal TP patients exhibit multiple CVD RF.

Proteinuria in Transplant Patients Associated With Sirolimus

Sirolimus (SRL) is a potent immunosuppressive drug used in organ transplantation for prophylaxis of acute allograft rejection. Conversion from calcineurin inhibitors to SRL has become an important alternative in patients with chronic allograft nephropathy. Recently, some reports have described the appearance of proteinuria after the use of SRL. The aim of the present study was to describe the incidence of proteinuria in transplant recipients receiving SRL in our transplant center. We studied 78 patients receiving SRL either de novo or after conversion. Eighteen transplant recipients (23.1%) developed proteinuria after SRL treatment. Proteinuria was diagnosed at 11.2 +/- 2.1 months after the initiation of SRL; in eight patients (44.4%) it occurred in the first 6 months. The mean value of proteinuria was 2.6 +/- 0.6 g/24 hours. In 5 patients (27.8%), proteinuria reached nephrotic levels, and in 13 patients (72.2%) was associated with edema. Renal allograft biopsies were performed before conversion to SRL, and a new biopsy, after the appearance of proteinuria. The light microscopy of biopsies performed after the onset of proteinuria showed no specific glomerular changes, except in 2 cases wherein the diagnosis was focal segmental glomerulosclerosis. Immunofluorescence was negative in all cases. In conclusion, in this study proteinuria was observed in 21.3% of patients receiving SRL therapy either as de novo protocol or after conversion to SRL. Proteinuria occurred early after the initiation of SRL therapy and in these cases, withdrawal of SRL was associated with reversion of proteinuria.