Abstract
Adult community-acquired pneumonia (ACAP) is the most prevalent pulmonary infectious disease that may be asymptomatic or have varying clinical presentations. Patients with ACAP often present with enlarged mediastinal lymph nodes on their chest computed tomography images. However, large irregular swollen lymph nodes are rarely reported in ACAP, and may therefore be confused with enlarged lymph node masses. In the present case report, the patient presented with lymph node masses, which were ameliorated to their normal size following antimicrobial treatment. The patient was 24 years old and otherwise healthy, which led to a pronounced and excessive immune response to pneumonia in the lymph nodes. Atypical pneumonia is difficult to diagnose based on imaging features. The present case report demonstrates that patients with pneumonia may present with unusually enlarged mediastinal lymph nodes, which are most likely, a result of a strong immune response to pneumonia.