A case of indirect exposure to cat at school.

Indirect exposure to cat allergens may exacerbate asthma in sensitized subjects. We report a case of a 13-year-old girl referred to our Unit for cough, dyspnea, wheezing, chest tightness, nasal itching and obstruction during the past six months, with improvement during summer holidays. Skin prick tests were positive for cat and Alternaria alternata. She had no cats at home. Spirometry was normal and methacoline bronchial challenge was negative. PEF monitoring showed a mean value of 80% of the predicted value with a variability higher than 20% in a few occasions. At a follow up visit PEF recording showed an increase of 80 litres/min during a 2 weeks Christmas holidays, and a subsequent reduction after being back at school. At a further questioning we found that in her class there was a girl who owned 23 cats. It is likely that PEF and symptoms in our patient were affected by indirect cat exposure at school.