Thoracic actinomycosis is a rare bacterial infection that affects the respiratory system, particularly the lungs and the thoracic cavity. This condition is also known by various synonyms such as pulmonary actinomycosis, thoracic actinobacillosis, and thoracic nocardiosis. It is caused by a type of bacteria called Actinomyces, which can spread from the dental cavity to the respiratory system. The symptoms of thoracic actinomycosis may vary from patient to patient and can range from chest pain, fever, cough, and shortness of breath. Treatment usually involves a long-term course of antibiotics. Early and accurate diagnosis is crucial to prevent further complications.