CRP13 BIRD FANCIER’S LUNG: A RARE CASE OF HYPERSENSITIVITY PNEUMONITIS IN CHILDHOOD

Nur Aishah Mazlan1, Mariana Daud2, Abdul Razak Hussin2
1Universiti Sains Malaysia, Kota Bharu, Malaysia
2 Hospital Raja Perempuan Zainab II, Kelantan, Malaysia

Hypersensitivity pneumonitis (HP) is a rare condition among children. It is an immune-mediated, heterogeneous form of interstitial lung disease (ILD) caused by repeated inhalation of environmental antigens. Bird fancier’s lung (BFL), a sub-type of ILD, results from the inhalation of bird antigens. We report a rare case of a young girl with HP due to BFL. 

SH initially presented at 6 years old with symptoms suggestive of pneumonia, on a background of a 4 months history of dry cough and reduced effort tolerance. Her recovery was suboptimal, with persistent respiratory distress and hypoxaemia despite antibiotic treatment and oxygen therapy. This warranted further investigations. Other aetiologies of ILD; infections, connective tissue disease and immunodeficiency were ruled out. The significant history of exposure to birds’ antigen since infancy, persistent respiratory symptoms, clinical suspicion and radiological features of ‘three-density’ pattern support the diagnosis of HP. Her underlying cardiac condition limits the invasive diagnostic procedures; bronchioalveolar lavage and lung biopsy. Over the course of treatment with pulses of corticosteroid followed by a combination therapy of tapering dose to low-dose oral steroid, inhaled corticosteroid (ICS), and an immunosuppressor, she showed a significant clinical response and radiological signs of improving lung fibrosis. 

In paediatrics population, HP can present with various clinical courses and commonly presented in subacute or chronic form, often with chronic cough and exertional dyspnea, which can be misdiagnosed as other respiratory illnesses.

This case underscores the importance of detailed environmental exposure history with chronic respiratory symptoms and highlights the diagnostic challenge of HP in paediatrics population. Early intervention with pulses of corticosteroid, along with avoidance of antigens are essential to improve clinical outcomes and prevent the progression to irreversible lung fibrosis.