2211. Impact of Early Fiberoptic Bronchoscopy on Microbiological Diagnostic Rate and Clinical Outcomes of Pneumonia in Acute Leukemia Patients

BACKGROUND: Fiberoptic bronchoscopy with BAL (FOB) remains the cornerstone in the diagnosis of pneumonia in immunocompromised patients; however, there is no uniform agreement on the best timing for FOB, and its impact on microbiological diagnostic rate and clinical outcome has not been established. METHODS: Retrospective study (October 2017–December 2017, July 2018–January 2019) at MD Anderson Cancer Center. The medical records of adult patients with AML, MDS or ALL who developed pneumonia (CAP, HCAP, HAP excluding VAP) and underwent FOB were reviewed. By definition, patients who underwent FOB within 48 hours after the diagnosis of pneumonia were categorized as early FOB group. We compared demographic, clinical, microbiological data, and outcomes between two groups. Data were analyzed via χ (2), Fisher’s exact and Wilcoxon rank-sum test and logistic regression. RESULTS: Of 140 patients included, 33 patients (24%) had early FOB and 107 patients (76%) had late FOB. There was no significant difference between two groups in demographic features, radiological findings, ANC and pneumonia severity index. Microbiological diagnostic rate of FOB did not differ between early FOB and late FOB: identification of pathogenic microorganisms (33.3% vs. 36.5%, p = 0.837), bacteria (6.1% vs. 13.1%, P = 0.36), fungi (18.2% vs. 12.2%, P = 0.39) and respiratory virus (12.1% vs. 16.8%, P = 0.6), respectively (Figures 1 and 2). On univariate analysis, the duration of intravenous antibacterial therapy was shorter in early FOB, with a median duration of 8.5 days (IQR 6.5–12) in early FOB and 11 days (IQR 8–18) in late FOB (P = 0.0047) (Figure 3). Multivariable logistic regression analysis showed that late FOB (OR 3.26, 95% CI 1.41 to 7.53, P = 0.0057) and negative bacterial culture on FOB (OR 3.06, 95% CI 1.01 to 9.22, P = 0.048) were significantly associated with longer duration of intravenous antibacterial therapy (≥10 days). There was no significant difference in ICU admission, 30-day and 60-day mortality and re-admission rate. CONCLUSION: Early FOB was associated with shorter duration of intravenous antibacterial therapy for pneumonia in acute leukemia patients, which has an important impact on both optimization of antimicrobial therapy for patients and improvement of antimicrobial stewardship. [Image: see text] [Image: see text] [Image: see text] DISCLOSURES: All authors: No reported disclosures.