Factors Associated with Colistin-Resistant Acinetobacter baumannii Acquisition among Hospitalized Patients
Peerayuth Pantuwadeethorn MD1, Amornrut Leelaporn PhD2, Pornpan Koomanachai MD1
Affiliation : 1 Department of Medicine, Faculty of Medicine Siriraj Hospital, Mahidol University, Bangkok, Thailand 2 Department of Microbiology, Faculty of Medicine Siriraj Hospital, Mahidol University, Bangkok, Thailand
Background : The emergence of multidrug-resistant Acinetobacter baumannii has led to the re-use of colistin. Colistin-resistant A.
baumannii [CRA] was rare but is being reported more often now.
Objective : To explore the factors associated with CRA.
Materials and Methods : A retrospective case-control study has conducted. The medical records of 20 patients with CRA and 80
patients with colistin-susceptible A. baumannii [CSA] were reviewed.
Results : Univariate analysis showed that presence of (cid:976)ive co-morbidities, intensive care unit stay, prior use of colistin, duration
of colistin use, and some prior antibiotics were associated with CRA (p<0.05). However, using multivariate analysis, prior colistin
and meropenem use had adjusted odds ratios [AOR] of 21.04; 95% CI of 3.11 to 142.32 (p = 0.002) and 13.54; 95% CI of 1.15 to
159.64 (p = 0.038), respectively, for CRA. Colistin duration (days) was signi(cid:976)icantly associated with resistance (AOR 1.22, 95% CI
of 1.04 to 1.44, p = 0.013).
Conclusion : These results should increase awareness of appropriate colistin administration i.e., the duration of colistin used.
Keywords : Acinetobacter baumannii, Colistin-resistant, Antibiotic used, Resistant factors, Polymyxin
