Radial endobronchial ultrasound-guided transbronchial biopsy (rEBUS-TBB) facilitates the diagnosis of peripheral lung lesions. However, methods to prevent infectious complications afterwards have not been well established. Therefore, we analyzed the efficacy of short-term oral antibiotics for preventing infectious complications.

We retrospectively analyzed 484 patients. Patients who underwent rEBUS-TBB from March 2018 to March 2019 did not receive prophylactic antibiotics (“no prophylactic” group, n = 233), while patients who underwent rEBUS-TBB from April 2019 to March 2020 did receive prophylactics (oral amoxicillin/clavulanate for 3 days; “prophylactic” group, n = 251). Multivariable logistic regression was used to identify independent factors for infectious complications.

The median age was 66 years (IQR: 59–74 years), and 58.9% were male. Slightly over half of the patients (54.4%) were previous or current smokers. In 13% (n = 63) of patients, the procedure was performed using a guide sheath. Infectious complications occurred in 12 (5.2%) and 2 (0.8%) cases in the no prophylactic and prophylactic groups, respectively. In multivariable analysis, infectious complications were significantly associated with a cavity or low-density attenuation (LDA) of the lesion, and with obstructive pneumonic consolidation, but not with prophylactic antibiotics. In subgroup analysis, infectious complications occurred less often when prophylactic antibiotics were used in patients with at least one risk factor (22.4% vs. 0%, p = 0.005).

The risk factors for infectious complications were cavities, LDA in the lesion, and obstructive pneumonic consolidation. Use prophylactic antibiotics might reduce incidence of infectious complications in the presence of these risk factors.