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Updated: Apr 19, 2026
Transcutaneous Assessment of Renal Function in Conscious Rodents
Published on: March 26, 2016
Trimethoprim and sulfamethoxazole transmembrane clearance during modeled continuous renal replacement therapy
Jacob M Kesner1, Joseph Michael Yardman-Frank, Renee-Claude Mercier
1College of Pharmacy, University of New Mexico, Albuquerque, NM, USA.
Background/Aims:
There is limited data regarding trimethoprim (TMP)/sulfamethoxazole (SMX) continuous renal replacement therapy (CRRT) dosing. We aimed to estimate TMP/SMX transmembrane clearance (CLtm) during continuous hemofiltration (CH) and continuous hemodialysis (CD) to guide dosing.
Methods:
Using an in vitro model, TMP/SMX sieving coefficients (SC) and saturation coefficients (SA) were determined with high-flux polyarylethersulfone and polyacrylonitrile-sodium methallyl sulfonate copolymer hemodiafilters at ultrafiltration/dialysate rates of 1, 2, 3, and 6 l/h. TMP/SMX CLtm was calculated using measured SC and SA. TMP/SMX CRRT doses were modeled using CLtm and published TMP/SMX pharmacokinetic parameters.
Results:
TMP SC/SA during CH/CD were significantly higher than SMX SC/SA. During modeling, TMP 10 mg/kg/day and its corresponding SMX dose, 50 mg/kg/day, resulted in steady state TMP/SMX peak concentrations associated with efficacy against Pneumocystis jirovecii.
Conclusions:
CRRT resulted in greater TMP CLtm than SMX. TMP 10 mg/kg/day divided q12h may be an appropriate initial dose to consider in patients undergoing CRRT.
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