A case of an occult bronchial foreign body in the right upper lung of an adult

Abstract Background Bronchial foreign bodies (BFBs) are less common in adults. An occult bronchial foreign body (OBFB) is a BFB with nontypical history, symptoms, physical signs and imaging, and is prone to either a delayed diagnosis, a missed diagnosis, or a misdiagnosis. There are no reported cases of adult OBFBs present in the upper lobe of the right lung alone. Case Description A 57-year-old previously healthy woman with no history of foreign body aspiration presented with recurrent cough and sputum that was present from August 2021 to May 2022. Her chest computed tomography (CT) suggested pneumonia in the upper lobe of the right lung, and tuberculosis had to be ruled out. After the laboratory tests to exclude tuberculosis were performed, she was diagnosed with pneumonia of the upper lobe of the right lung. Her symptoms were still recurrent after anti-infection and expectorant treatment. Finally, a yellowish-white substance (curd-like or cottage cheese-like) was found in the upper lobe of the right lung under flexible bronchoscopy, and the patient's cough and sputum symptoms were significantly relieved after removal of the substance. Conclusions OBFBs in adults are clinically rare and are prone to either a delayed diagnosis, a missed diagnosis or a misdiagnosis. A patient can be suspected of having a BFB after meeting the 4 conditions of OBFB and having any one indicator—risk factors, indirect signs of lesions on CT, or recurrent respiratory symptoms after treatment. Flexible bronchoscopy is necessary, and rigid bronchoscopy and surgery can be alternate means.