Unmasking the Hidden Culprit: A Case of Pulmonary Actinomycosis

Abstract Pulmonary actinomycosis is a rare and challenging condition to diagnose, caused by anaerobic or microaerophilic bacteria, primarily from the genus Actinomyces. There is often a delayed diagnosis, or it may masquerade as tuberculosis, a lung abscess, or lung cancer. This masquerading, particularly as a malignancy, is distressing for the patient, who may undergo surgery for what is essentially a benign and curable disease. Here, we report a case of a 60-year-old male who presented with complaints of cough and minimal expectoration for three months, along with a non-resolving opacity on a chest X-ray. The diagnostic workup confirmed the diagnosis of pulmonary actinomycosis. This case highlights the diagnostic challenges posed by actinomycosis and illuminates the clinical, diagnostic, and therapeutic characteristics of the disease.