The Little Farmer’s Lung: Hypersensitivity Pneumonitis Due to Multiple Fungal Triggers in a 6-Year-Old

B. M. Seay, T. Bui, D. R. Ezmigna, M. Abu-hasan;

Author address: 

Pediatric Pulmonology Division, University of Florida, Gainesville, FL, United States.

Abstract: 

Introduction: Hypersensitivity Pneumonitis (HP) is a relatively uncommon disease with low prevalence and incidence in adults exposed to a group of recognized organic inhaled antigens. Children are also susceptible to HP, albeit rarely, with a larger number of possible triggers1. We report a case of a pediatric patient diagnosed with HP that was triggered by Aspergillus Fumigatus, Thermoactinomyces Candidus, and Thermoactinomyces Sacchari.
Case description: The patient is a 6-year-old male with past medical history of asthma who presented with cough, wheezing, and increased work of breathing requiring 3 emergency room visits and 1 admission over the last 2 months. He received albuterol and systemic steroids to which he did not respond completely. Vital signs showed tachypnea (36 bpm), but otherwise were within normal limits. Physical examination was significant for diffuse crackles on auscultation and bilateral clubbing. Chest x-ray showed patchy bilateral opacities. Chest CT showed diffuse ground glass opacities throughout both lungs with no bronchiectasis (Figure1). Total serum IgE was elevated at 1164 kU/L. Further history taking revealed the patient had numerous exposures to the skinning and eating of wild game, and exposure to soil due to his father serving as a landscaper. Bronchoscopy and Bronchoalveolar lavage (BAL) were performed. BAL fluid contained 79% neutrophils, 17% lymphocytes, 4% monocytes, and O% eosinophils. On BAL cytology eosinophils were present. Transbronchial biopsy was performed due to concern for possible ILD and showed extensive lymphocytic interstitial pneumonitis, chronic bronchiolitis, and ill-formed non-necrotizing granulomas, consistent with HP. HP immune precipitation panel was positive for IgG to Aspergillus Fumigatus, Thermoactinomyces Candidus, and Thermoactinomyces Sacchari. Anti-Ascaris antibodies were high which was suspicious for parasitic infection, but three stool ova and parasite specimens were all negative.
Discussion: The most common triggers for HP are usually bird antigens. Exposure to Aspergillus and Thermoactinomyces are not common triggers for pediatric HP, however in this patient these were the only allergens detected on immune precipitation. There are only 3 previous case reports published that showed Aspergillus as the trigger for HP in children2-4. Other confounders in the initial diagnosis were the elevated IgE level and eosinophils on cytology which do not fit with HP. The high Ascaris antibody levels can explain the IgE elevation.
Conclusion: This case demonstrates that HP is a diagnosis that can easily be missed in a pediatric patient presenting with asthma-like symptoms. Also Aspergillus and Thermoactinomyces should be considered as triggers in possible HP.

Tables: 

2018

abstract No: 

A5647 / P1093

Full conference title: 

The American Thoracic Society Conference 2018
    • ATS 2018