Bird fanciers' lung induced by exposure to duck and goose feathers

Female, 60 FINAL DIAGNOSIS: Bird fanciers' lung Symptoms: Cough productive • hypoxia • short of breath • substernal chest pain

- Clinical Procedure: - Specialty: -

Rare disease.

Hypersensitivity pneumonitis (HP) is a group of inflammatory interstitial lung diseases caused by hypersensitivity reactions from repeated insults of inhalation of fine particulate organic dusts derived from environmental sources. Bird fanciers' lung (BFL) is the most common form of HP, with an estimated prevalence of 0.5-7.5% and is observed in individuals who develop a hypersensitivity response to avian droppings or antigens on bird feathers.

A 60-year-old woman presented to our care with shortness of breath with exertion. She was hypoxic with oxygen saturation of 70% on room air. The CTA of the chest revealed a diffuse bilateral ground glass density in the lung parenchyma with a mosaic attenuation pattern. On further questioning she explained that she collected many duck and goose feathers she found on the ranch and placed them in a vase at home. Transbronchial lung biopsy revealed non-caseating granulomas, aggregates of epithelioid macrophages, and patchy mononuclear cell infiltration with lymphocytes and fibrotic tissue. The patient clinically improved and was discharged home on the 6(th) hospital day with prednisone 20 mg daily, with clinical improvement noted on subsequent follow up visits.

There is no specific clinical manifestation; abnormal laboratory test results help establish a definitive diagnosis. The best diagnostic tool is the correlation of symptom onset with the environmental exposure. The prognosis is excellent after a single episode of HP, but continuous re-exposure carries the risk of progressive pulmonary impairment.