[Cough, bloody sputum, eosinophil elevation and lung shadow]

Area of Science:

• Pulmonology
• Infectious Diseases
• Parasitology

Background:

• Pulmonary hydatidosis is a parasitic infection caused by Echinococcus tapeworms.
• It often presents with vague respiratory symptoms, mimicking other lung conditions.
• Eosinophilia can be a key indicator in diagnosing parasitic infections.

Observation:

• A 47-year-old man presented with chronic cough and hemoptysis.
• Initial CT revealed a lung nodule, which enlarged over two years.
• Elevated eosinophils and CT findings suggested parasitic infection.

Findings:

• Needle biopsy confirmed pulmonary hydatidosis, revealing characteristic cyst structures and hooklets.
• The patient's symptoms resolved, and lung nodules decreased in size over a 5-year follow-up, even without specific treatment.

Implications:

• This case highlights the importance of considering parasitic infections in pulmonary nodule diagnosis.
• It suggests that some cases of pulmonary hydatidosis may be managed conservatively with favorable outcomes.