ABSTRACT
BACKGROUND: Warfarin is the most frequently prescribed anticoagulant in North America and Europe. It is administered as a racemate, but S-warfarin is principally responsible for its anticoagulant activity. Cytochrome P450 (CYP) 2C9 is the enzyme primarily responsible for the metabolism of S-warfarin. Numerous variant alleles of CYP2C9 have been identified. The CYP2C9*12 (rs9332239) allele harbors a P489S substitution in CYP2C9 which has been shown to result in a 40% decline in catalytic activity in vitro. CASES: Four Caucasian patients with a low mean weekly warfarin dose (MWWD) were genotyped for CYP2C9, VKORC1 and APOE variant alleles. None of the four patients carried the common CYP2C9 variant alleles (*2, *3, *5, *6, *7, *8, *9, *11, *13) despite a relatively low MWWD (23.4±7.94 mg) compared to 208 patients carrying the CYP29C9*1 genotype (32.2±12.65 mg). Given that CYP2C9*12 confers decreased in vitro activity to the enzyme, we investigated whether these patients carried this allele. All four patients were CYP2C9*12 CT heterozygotes. Individual comparisons with patients possessing the same VKORC1 and APOE genotypes also demonstrated lower dose requirements in the patients that possessed CYP2C9*12 allele. CONCLUSIONS: There are no reports of the clinical impact of rs9332239 on CYP2C9 substrates. This is the first report of patients with the rare CYP2C9*12 genotype and lower warfarin dose requirements.
Subject(s)
Anticoagulants/metabolism , Aryl Hydrocarbon Hydroxylases/genetics , Mutation , Thromboembolism/genetics , Warfarin/metabolism , Aged , Aged, 80 and over , Alleles , Amino Acid Substitution , Anticoagulants/therapeutic use , Apolipoproteins E/genetics , Aryl Hydrocarbon Hydroxylases/metabolism , Base Sequence , Biotransformation , Cytochrome P-450 CYP2C9 , Drug Dosage Calculations , Female , Genotype , Genotyping Techniques , Heterozygote , Humans , Male , Middle Aged , Molecular Sequence Data , Thromboembolism/enzymology , Thromboembolism/pathology , Thromboembolism/prevention & control , Vitamin K Epoxide Reductases/genetics , Warfarin/therapeutic useABSTRACT
Catheter-associated urinary tract infections (CAUTIs) are preventable complications of hospitalization. An interdisciplinary team developed a curriculum to increase awareness of the presence of indwelling urinary catheters (IUCs) in hospitalized patients, addressed practical, primarily nurse-controlled inpatient risk-reduction interventions, and promoted the use of the IUC labels ("tags"). Five thirty-minute educational sessions were cycled over three daily nursing shifts on two inpatient medical floors over a 1-year period; participants were surveyed (n = 152) to elicit feedback and provide real-time insight on the learning objectives. Nurse self-reported IUC tagging was early and sustained; after the IUC tag was introduced, there was a significant increase in tagging reported by the end of the block of educational sessions (from 46.2% to 84.6%, P = 0.001). Early engagement combined with a targeted educational initiative led to increased knowledge, changes in behavior, and renewed CAUTI awareness in hospitalized patients with IUCs. The processes employed in this small-scale project can be applied to broader, hospitalwide initiatives and to large-scale initiatives for healthcare interventions. As first-line providers with responsibility for the placement and daily maintenance of IUCs, nurses are ideally positioned to implement efforts addressing CAUTIs in the hospital setting.
