# Bronchiectatic Actinomycosis with Osseous Metaplasia Masquerading as Lung Cancer

## TL;DR

A rare case of bronchiectatic actinomycosis with osseous metaplasia was diagnosed in a patient initially suspected of having lung cancer.

## Contribution

This case report highlights a rare presentation of actinomycosis without foreign body aspiration, associated with bronchiectasis.

## Key findings

- The patient's symptoms and imaging mimicked lung cancer but were due to actinomycosis with osseous metaplasia.
- The diagnosis was confirmed via segmental resection and responded well to prolonged antibiotic treatment.
- Bronchiectatic actinomycosis can present with atypical cells and persistent consolidation, leading to diagnostic challenges.

## Abstract

Bronchial involvement in pulmonary actinomycosis is rare and has been reported in the literature rarely. However, these reports describe endobronchial actinomycosis secondary to foreign body aspiration (for example, a fish bone). Our case did not have any history or clinical evidence suggesting foreign body aspiration, which makes it even more rare.

A 55-year-old woman presented with complaints of on and off haemoptysis and cough for three weeks. In view of the haemoptysis and consolidation seen on imaging, a bronchoalveolar lavage was done and sent for cytological assessment. Few atypical cells with nuclear hyperchromasia and prominent nucleoli were noted. In view of the persistent haemoptysis, worsening symptoms, and non-resolution of the consolidation despite antibiotics, and the finding of atypical cells, segmental resection was done. A final diagnosis of bronchiectatic actinomycosis with osseous metaplasia was given. The patient was started on prolonged antibiotics with good response and recovery.

Other risk factors associated with pulmonary actinomycosis include alcoholism, diabetes, haematological diseases, human immunodeficiency viral infection, use of immunosuppressants, and rarely chronic lung diseases, such as bronchiectasis. Our case had this rare association of bronchiectasis with bronchial actinomycosis.

Bronchiectatic actinomycosis is a rare infection and it can mimic several lung disorders like unresolving pneumonia, pulmonary tuberculosis, foreign body, and even lung tumours. The pathologists and clinicians should be aware of this entity and thus help in the early diagnosis and better management of patients with this disease.