Orthotopic Heart Transplant Recipient with Enteric-coated Mycophenolate Sodium (Myfortic) Induced Colitis

Area of Science:

• Transplantation medicine
• Gastroenterology
• Pharmacology

Background:

• Mycophenolic acid is a key immunosuppressant in solid organ transplantation.
• Two preparations exist: mycophenolate mofetil (Cellcept) and enteric-coated mycophenolate sodium (Myfortic).
• Myfortic was developed to mitigate gastrointestinal side effects associated with Cellcept.

Observation:

• A 66-year-old male heart transplant recipient developed worsening diarrhea post-immunosuppression switch from Cellcept to Myfortic.
• Extensive workup for diarrhea was inconclusive.
• Colonoscopy with biopsy revealed mycophenolic acid-induced colitis.

Findings:

• Enteric-coated mycophenolate sodium-induced colitis is exceptionally rare, with no prior reports in heart transplant patients.
• Discontinuation of enteric-coated mycophenolate sodium led to marked symptom improvement within 48 hours.
• The patient showed no signs of colitis or graft rejection at 7-month follow-up.

Implications:

• Enteric-coated mycophenolate sodium-induced colitis should be considered in heart transplant patients presenting with diarrhea.
• Prompt diagnosis and drug discontinuation can resolve symptoms and prevent unnecessary investigations.
• Vigilant monitoring for allograft rejection is essential after discontinuing immunosuppression.