title: Evaluation of the genetic background of standard-immunosuppressant-related toxicity in a cohort of 200 paediatric renal allograft recipients--a retrospective study.
abstract: BACKGROUND
  Immunosuppressant toxicity is a limiting factor for the efficacy and safety of long-term therapy. Whether it stems solely from drug exposure, remains unclear.
  
  
  METHODS
  Overall, 207 children and adolescents at the mean age of 11+/-4.4, with primary renal allograft were analyzed. Immunosuppression regimens included CsA or TAC, combined with AZA or MMF and steroids. Drug-specific toxicities were diagnosed by renal biopsy and/or clinical criteria. Genotyping for MDR1, CYP3A5, IL1B, IL1RN, IL-6, IL-10, MCP-1, TGFB1, CCR5, VEGF and TNF-alpha gene polymorphisms was performed with the use of PCR and PCR-RFLP techniques.
  
  
  RESULTS
  Nephrotoxicity was seen in 38.5% of patients treated with CsA and 29.5% - with TAC, while gingival hypertrophy was observed in 28% of CsA patients. Myelotoxicity was found in 3% of AZA-treated and 6.4% of MMF-treated patients. No significant correlation was seen between the patient's age, gender, type of pre-transplantation dialysis, donor age, graft origin or cold ischemia time, and the occurrence of drug-related toxicity. For CNIs, the drug exposure and the duration of treatment did not prove of significance either. TAC associated nephrotoxicity correlated with the CCR5 gene polymorphism, as the wt/32 genotype was found in 21% of patients with no detected toxicity (p<0.041) and in none of the nephrotoxicity cases. The presence of this genotype was also associated with significantly better graft function at 1 year post-transplant (GFR 115.104+/-28.40 vs 86.434+/-29.96; p=0.022). An association was seen between the MMF-induced myelotoxicity and the TNF-alpha G(-308)A polymorphism (p<0.005), but the MMF exposure was higher in patients who developed toxicity.
  
  
  CONCLUSIONS
  Genetic background should be regarded one of the risk factors for immunosuppressant related toxicity in renal transplantation.
authors: Department of Nephrology, Kidney Transplantation and Hypertension Children's Memorial Health Institute, Warsaw, Poland. r.grenda@czd.pl
authors: Ryszard
authors: R
authors: Grenda
authors: Sylwester
authors: S
authors: Prokurat
authors: Andrzej
authors: A
authors: Ciechanowicz
authors: Barbara
authors: B
authors: Piatosa
authors: Piotr
authors: P
authors: Kaliciński
mesh_terms: D000293:Adolescent; D001379:Azathioprine / Q000009:adverse effects; D001483:Base Sequence; D065095:Calcineurin Inhibitors; D002648:Child; D015331:Cohort Studies; D016572:Cyclosporine / Q000009:adverse effects; D017931:DNA Primers / Q000235:genetics; D005260:Female; D006801:Humans; D007166:Immunosuppressive Agents / Q000009:adverse effects*; D007668:Kidney / Q000187:drug effects / Q000473:pathology; D016030:Kidney Transplantation / Q000009:adverse effects* / Q000276:immunology*; D008297:Male; D009173:Mycophenolic Acid / Q000009:adverse effects / Q000031:analogs & derivatives; D010597:Pharmacogenetics; D011110:Polymorphism, Genetic; D019713:Receptors, CCR5 / Q000235:genetics; D012189:Retrospective Studies; D016559:Tacrolimus / Q000009:adverse effects
chemical_list: D065095:Calcineurin Inhibitors; D017931:DNA Primers; D007166:Immunosuppressive Agents; D019713:Receptors, CCR5; D016572:Cyclosporine; D009173:Mycophenolic Acid; D001379:Azathioprine; D016559:Tacrolimus