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Mycophenolate mofetil absorption quotient: interest to clinical practice.
A Fernández1, J Villafruela, Y Amezquita
1Department of Nephrology, Hospital Ramón y Cajal, Madrid, Spain. afernandezr.hrc@salud.madrid.org
Transplantation Proceedings
|September 1, 2009
Summary
Mycophenolate mofetil (MMF) levels in kidney transplant patients correlate with dosage but not absorption. Gastrointestinal issues, like diarrhea, may indicate reduced MMF absorption in stable transplant recipients.
Area of Science:
- Nephrology
- Immunosuppression
- Transplantation medicine
Background:
- Mycophenolate mofetil (MMF) is crucial for improving acute rejection rates and graft survival in kidney transplantation.
- Monitoring post-transplant MMF levels aids in identifying patients at risk of acute rejection.
Purpose of the Study:
- To evaluate the diagnostic value of the quotient between weight-adjusted MMF dose and trough levels for assessing absorption in stable kidney transplant patients.
- To analyze the relationship between this quotient and clinical outcomes like creatinine, proteinuria, and toxicity.
Main Methods:
- Measured trough MMF levels in 153 stable kidney transplant recipients (>1 year post-transplant).
- Calculated the dose-to-level quotient to categorize absorption.
- Analyzed the quotient's correlation with creatinine, proteinuria, and gastrointestinal/hematologic toxicity using percentiles as cutoffs.
Main Results:
- A significant correlation was observed between MMF dosage and trough levels (r = .34, P < .01).
- No correlation was found between MMF dosage and the calculated absorption quotient.
- Patients experiencing gastrointestinal toxicity exhibited a significantly larger quotient (9.07 +/- 7.45 vs 5.28 +/- 4.9), suggesting potential absorption issues.
Conclusions:
- The MMF dose-to-level quotient does not reliably differentiate kidney function or proteinuria in stable transplant patients.
- Gastrointestinal toxicity, particularly diarrhea, may be associated with reduced MMF absorption in this population.
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