title: Cyclosporine therapeutic monitoring with Cmax in kidney transplant recipients: does it fit for all populations?
abstract: BACKGROUND
  We sought to assess whether the single cyclosporine concentration taken 2 hours after administration (C2) is a good parameter to predict a drug's maximal concentration (Cmax) value in Egyptian kidney transplant recipients.
  
  
  METHODS
  Fifty stable Egyptian kidney transplant recipients with a previously diagnosed schistosomal infection were compared with 50 Egyptian kidney transplant recipients without a schistosomal infection regarding cyclosporine concentrations at time 0 (trough), and then at 1.5, 2, 2.5, 3, and 3.5 hours after a dose of cyclosporine. We used a linear regression analysis to assess any statistically significant differences between the different cyclosporine time concentrations and drug dosages.
  
  
  RESULTS
  Patients in the schistosomal group had significantly lower C2 levels (511 -/+ 118 nmol/L) compared with those in the nonschistosomal (control) group (669 -/+ 213 nmol/L) (P < .05), whereas the C2.5 level was significantly higher (730 -/+ 215 and 527 -/+ 129 nmol/L, respectively; P < .05). A significant linear regression relation was determined for only C2.5 in the schistosomal group with both morning cyclosporine dose and cyclosporine dose expressed as mg/kg/d (P = .0123, r = .573018).
  
  
  CONCLUSIONS
  Egyptian patients have special characteristics with regard to drug absorption and metabolism, mostly owing to schistosomal infection, and they may need the use of C2.5 to monitor cyclosporine. If confirmed by subsequent, larger studies, our findings may have a significant effect on our understanding and management of cyclosporine immunosuppression in clinical renal transplants with persons of different ethnicities.
authors.affiliation: Urology & Nephrology Center, Mansoura University, Mansoura, Egypt. amgadelagroudy@hotmail.com
authors.forename: Amgad E
authors.initials: AE
authors.lastname: El-Agroudy
authors.forename: Amani M
authors.initials: AM
authors.lastname: Ismail
authors.forename: Mohamed
authors.initials: M
authors.lastname: Nassar
authors.forename: Mohamed A
authors.initials: MA
authors.lastname: Ghoneim