Introduction

Chronic hypersensitivity pneumonitis (cHP) has a poor prognosis when no antigen is identified, which occurs in up to 60% of cases. Foam in bedding is not a recognized cause of cHP.

Methods

Through standardized questionnaires and following current guidelines, we investigate known causes of interstitial lung diseases (ILD) in all new patients referred to our ILD clinic. Hypersensitivity pneumonitis in these cases was diagnosed based on exposures, imaging, bronchoalveolar lavage, and/or lung biopsy.

We report molds isolated from foam samples in 10 cases of cHP associated to foam exposure in pillows and mattresses - a novel cause of cHP. 

Results

Mean age was 70 years (min 50-max 88), 6 females and 4 males. cHP diagnosis was presumed or confirmed  through biopsy and multidisciplinary discussion in 60% (6/10) of patients, BAL lymphocytosis (>30% lymphocytes) in 3 patients and HRCT typical of fibrotic HP in one case. We found a total of 10 molds in the foam samples analyzed: 8 different molds in 4 mattresses and 8 different molds in 7 pillows (see table), most known to cause HP.

Conclusion

Molds in foam pillows and mattresses may explain cHP cases with previously unrecognized causes. Early identification and avoidance of foam in bedding may prevent cHP progression to end stage pulmonary fibrosis and death.

Table. Molds recovered from foam in bedding in 10 patients with cHP.