A retrospective cohort study to screen linezolid-induced thrombocytopenia in adult patients hospitalized in the Midwestern Region of Brazil

BACKGROUND: Thrombocytopenia (TP) is the major event associated with linezolid (LZD) therapy. We investigated the incidence and risk factors for thrombocytopenia in hospitalized adults who received LZD (1200 mg/day) between 2015 and 2017. HIV-positive, death during follow-up and those with a baseline platelet count ≤100 × 10(3)/mm(3) were excluded. METHOD: TP was defined as a decrease in platelet count of ≥20% from the baseline level at the initiation of linezolid therapy and a final count of <100 × 10(3)/mm(3). The odds ratios (OR) for thrombocytopenia were obtained using multivariate stepwise logistic regression analysis. MAIN RESULTS: A total of 66 patients were included (mean age [SD] 62 [18], male gender [%], 37 [56]). LZD-associated TP was identified in 12 patients (18.2%). For TP, the adjusted OR [95% CI] of the platelet count ≤200 × 10(3)/mm(3), serum creatinine and renal impairment at baseline were 5.66 [1.15–27.9], 4.57 [1.26–16.5] and 9.41 [1.09–80.54], respectively. Male gender and dosage per weight per day (DPWD) >20 mg/kg/day were not risk factors. CONCLUSION: The results showed that the incidence of linezolid-induced thrombocytopenia was lower in patients with normal renal function and higher in those with platelet counts ≤200 × 10(3)/mm(3) or serum creatinine >1.5 mg/dL at the start of the treatment.