title: Incidence and predictors of nephrotoxicity associated with intravenous colistin in overweight and obese patients.
abstract: Intravenous colistin is used to treat resistant Gram-negative infections and is associated with nephrotoxicity. In overweight and obese adults, a paucity of data exists regarding the incidence and predictors of such toxicity. A retrospective nested case-control study was performed over 35 months for patients receiving intravenous colistin for ≥ 72 h with a body mass index (BMI) of ≥ 25 kg/m(2). The objective was to investigate the incidence and predictors of nephrotoxicity. Severity of acute kidney injury was defined by RIFLE (risk, injury, failure, loss, and end-stage kidney disease) criteria. Dosing and mortality were secondarily investigated. Forty-two patients met the inclusion criteria, and 20 (48%) developed nephrotoxicity. Patients with toxicity were in the risk (15%), injury (5%), and failure (80%) categories based on RIFLE criteria. A logistic regression model identified four predictors of colistin-associated nephrotoxicity: a BMI of ≥ 31.5 kg/m(2) (odds ratio [OR], 3.1; 95% confidence interval [CI], 1.15 to 8.35), diabetes (OR, 2.11; 95% CI, 0.84 to 5.29), the length of hospitalization in days prior to receipt of colistin (OR, 1.04; 95% CI, 0.99 to 1.08), and age (OR, 1.08; 95% CI, 1.00 to 1.17). Among all of the patients, dosing based on the actual body weight and excessive dosing due to the use of the actual body weight were frequent at 64% and 92%, respectively. The 30-day all-cause in-hospital mortality rate was 40% in the toxicity group and 14% in the nontoxicity group (P = 0.14). Patients receiving intravenous colistin should be monitored for nephrotoxicity, especially when the BMI exceeds 31.5 kg/m(2). Prospective, randomized, controlled trials are warranted to further examine nephrotoxicity incidence and predictors and appropriate dosing strategies in this population.
authors.affiliation: Department of Pharmacy Practice, Nova Southeastern University College of Pharmacy, Fort Lauderdale, Florida, USA. Timothy.Gauthier@nsu.nova.edu
authors.forename: Timothy P
authors.initials: TP
authors.lastname: Gauthier
authors.forename: William R
authors.initials: WR
authors.lastname: Wolowich
authors.forename: Arathi
authors.initials: A
authors.lastname: Reddy
authors.forename: Ennie
authors.initials: E
authors.lastname: Cano
authors.forename: Lilian
authors.initials: L
authors.lastname: Abbo
authors.forename: Laura B
authors.initials: LB
authors.lastname: Smith
mesh_terms: D058186:Acute Kidney Injury / Q000139:chemically induced* / Q000401:mortality; D000328:Adult; D000368:Aged; D000900:Anti-Bacterial Agents / Q000008:administration & dosage / Q000009:adverse effects*; D015415:Biomarkers / Q000032:analysis; D015992:Body Mass Index; D016022:Case-Control Studies; D003091:Colistin / Q000008:administration & dosage / Q000009:adverse effects*; D054796:Drug Dosage Calculations; D005260:Female; D006090:Gram-Negative Bacteria / Q000187:drug effects / Q000502:physiology; D017052:Hospital Mortality; D006801:Humans; D007275:Injections, Intravenous; D007668:Kidney / Q000187:drug effects* / Q000473:pathology; D007676:Kidney Failure, Chronic / Q000139:chemically induced* / Q000401:mortality; D016015:Logistic Models; D008297:Male; D008875:Middle Aged; D009765:Obesity / Q000188:drug therapy / Q000382:microbiology / Q000473:pathology; D050177:Overweight / Q000188:drug therapy / Q000382:microbiology / Q000473:pathology; D012189:Retrospective Studies; D012307:Risk Factors; D012720:Severity of Illness Index; D014481:United States
chemical_list: D000900:Anti-Bacterial Agents; D015415:Biomarkers; D003091:Colistin