High dose intravenous colistin methanesulfonate therapy is associated with high rates of nephrotoxicity; a prospective cohort study from Saudi Arabia.

BACKGROUND: Nephrotoxicity is an important adverse effect of colistin methanesulfonate (CMS) therapy. No data exist on rates and risk factors for colistin-related nephrotoxicity in Saudi Arabia (SA). We conducted a prospective cohort study to identify rates and risk factors for CMS nephrotoxicity in our patient population. METHODS: We prospectively included adult patients who received ≥48 hours of intravenous CMS therapy. Pregnant patients and those on renal replacement were excluded. Patients received 9 million units (mU) loading dose followed by 3 mU 8 hourly. In renal impairment, CMS dosing was adjusted according to calculated creatinine clearance (CrCl). Nephrotoxicity was defined as per RIFLE criteria (Risk, Injury, Failure, Loss and End-stage renal disease). Statistical analysis was performed using SPSS version 20.0 (IBM, Armonk, New York, USA). The study was approved by the institution's Research Ethics Committee. RESULTS: A total of 67 patients were included in the study. Mean (±standard deviation) age was 57.5 (±24.0) years, Charlson Co-morbidity Score 2.88 (±2.39), CrCl 133.60 (±92.54) mL/min and serum albumin 28.65 (±4.45) g/L. Mean CMS dose was 0.11 (±0.04) mU/kg/day and mean total CMS dose received was 101.21 (±47.37) mU. Fifty-one (76.1%) patients developed RIFLE-defined nephrotoxicity. Mean total CMS dose and duration of therapy before onset of nephrotoxicity were 66.71 (±43.45) mU and 8.70 (±6.70) days, respectively. In bivariate analysis, patients with nephrotoxicity were significantly older (P 0.013) and had lower baseline serum albumin (P 0.008). Multivariate logistic regression identified serum albumin [odds ratio (OR) 0.72; 95% confidence interval (CI) 0.57-0.93; P 0.010] and intensive care admission (OR 16.38; 95% CI 1.37-195.55; P 0.027) as independent risk factors for CMS nephrotoxicity. CONCLUSIONS: High dose intravenous CMS therapy is associated with high rates of nephrotoxicity in SA. Independent risk factors for colistin nephrotoxicity were baseline hypoalbuminemia and intensive care admission.

Physicians' knowledge, perceptions, and attitudes toward antimicrobial prescribing in Riyadh, Saudi Arabia.

OBJECTIVES: To assess knowledge, perceptions, and attitudes toward antimicrobial prescribing among physicians practicing in Riyadh, Saudi Arabia. METHODS: A questionnaire was developed and distributed to physicians working in hospitals in Riyadh, Saudi Arabia between June and August 2013. The results were analyzed using Stata 12 software. RESULTS: Two hundred and twelve (84.8%) full responses were returned. Most respondents perceived antimicrobial resistance as a significant problem in their daily practice (119, 56.1%) and at a national level (148, 69.8%). Inappropriate empirical therapy (101, 47.6%) and excessive use of antimicrobials in healthcare settings (66, 31.1%) were believed to be the main contributors to increasing bacterial resistance. Respondents favor treating infection rather than colonization (98, 46.2%), and physician education (74, 34.9%) as the most effective interventions to reduce antimicrobial resistance. Many respondents (95, 44.8%) do not feel confident in their knowledge of antimicrobial prescribing. Two-thirds of the respondents (135, 63.7%) have local antimicrobial guidelines, of which 90 (66.7%) felt were useful. Most respondents (160, 75.5%) considered their local infectious diseases service to be very helpful. CONCLUSION: There are considerable unmet training and education need for physicians in the area of antimicrobial prescribing. Local antimicrobial guidelines need revision to ensure they are more relevant and helpful for medical practitioners.