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 (1200mg/day) between 2015 and 2017. HIV-positive, death during follow-up and those with a baseline platelet count ≤100×10/mm 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/mm. 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/mm, 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) >20mg/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/mm or serum creatinine >1.5mg/dL at the start of the treatment.