# Incidental Pulmonary Actinomycosis in a Patient With a Pancreatic Pseudocyst

## TL;DR

A 57-year-old woman with a pancreatic pseudocyst was found to have an incidental case of pulmonary actinomycosis, highlighting the need for better diagnostic approaches for this rare infection.

## Contribution

This case report adds to the limited literature on incidental pulmonary actinomycosis and emphasizes the importance of improved diagnostic recognition.

## Key findings

- Pulmonary actinomycosis was diagnosed incidentally during evaluation of a pancreatic pseudocyst.
- Periodic acid-Schiff staining confirmed the presence of Actinomyces in the lung.
- The case highlights the nonspecific nature of symptoms and imaging findings in pulmonary actinomycosis.

## Abstract

Pulmonary actinomycosis is a rare manifestation of Actinomyces infection and is linked to aspiration, poor oral hygiene, and respiratory disease. Although timely treatment leads to favorable outcomes, pulmonary Actinomyces infection often presents with nonspecific symptoms and imaging findings, delaying appropriate interventions. Our 57-year-old female patient with a history of oral cancer and chronic pancreatitis presented to the emergency department with anorexia, weakness, nausea, and diarrhea. Chest and abdominal imaging raised concerns for pancreatic disease and, to our interest, an upper lobe pleural effusion. The patient was diagnosed with a pancreatic pseudocyst, and further pulmonological testing led to the additional diagnosis of pulmonary actinomycosis, ultimately confirmed by periodic acid-Schiff staining. The pulmonary infection was an incidental finding that proved to be crucial for the patient’s recovery. This case report underscores the need for further research into pulmonary actinomycosis to identify potential patterns in its clinical presentation and imaging, with the aim of improving diagnostic techniques and time to appropriate interventions.