Clostridium difficile-Associated Colitis Post-Transplant Is Not Associated with Elevation of Tacrolimus...

Area of Science:

• Transplant medicine
• Pharmacology
• Infectious diseases

Background:

• Diarrhea is common post-solid organ transplant (SOT).
• Clostridium difficile-associated colitis (CDAC) is a frequent SOT infection.
• Previous studies linked enteritis to altered tacrolimus (TAC) levels.

Purpose of the Study:

• To investigate the impact of CDAC on tacrolimus (TAC) trough concentrations in SOT recipients.
• To compare TAC level changes in CDAC versus other forms of infectious diarrhea.

Main Methods:

• Retrospective analysis of TAC concentrations in 25 SOT recipients (12 renal, 13 liver).
• TAC levels were measured before, during, and after CDAC episodes.
• CDAC was treated with metronidazole.

Main Results:

• No significant change in median TAC concentrations was observed during CDAC (5.6 ng/mL) compared to pre-CDAC (6.9 ng/mL) and post-CDAC (7.4 ng/mL) levels.
• The p-value for TAC concentration changes was greater than 0.05 (not significant).
• All patients recovered from CDAC, with seven experiencing relapse.

Conclusions:

• CDAC does not elevate TAC concentrations in SOT recipients, unlike other infectious diarrheas.
• This difference is attributed to C. difficile primarily affecting the colon, whereas other pathogens impact the small intestine, altering drug metabolism.