Nocardia beijingensis lung mass in an immunocompetent adult

A 47-year-old man was referred for ongoing workup of an enlarging lung mass. Extensive workup of the mass had been unrevealing for several months until cultures grew Nocardia beijingensis. He was successfully treated with trimethoprim/sulfamethoxazole and then doxycycline with near-complete resolution of the mass on follow-up. This case presents a rare species of N. beijingensis. It highlights the importance of considering nocardiosis in immunocompetent adults and the challenge in initiating targeted treatment due to delayed culture results.