Asthma caused by potassium aluminium tetrafluoride: a case series

The objective of this study is to describe a case-series of potassium aluminiumtetrafluoride (KAlF₄)-induced occupational asthma (OA) and/or occupationalrhinitis (OR). The study involves five patients from a heat-exchanger production line whowere examined (including specific inhalation challenge tests) for suspected OA and/or ORcaused by a flux containing almost 100% KAlF₄ − with fluorides’ workplace airconcentrations ranging between 1.7 and 2.8 mg/m³. No subject had a previoushistory of asthma. All five patients had a positive specific challenge test (threepatients were diagnosed with OA alone, one with OR and one with both OR and OA). At thefollow-up visit, after three years on average, all patients needed permanentcorticosteroid therapy (four topical, one oral). After elimination from the exposure, onlyone of the observed subjects gave an indication of an improvement, two subjects stabilizedand two worsened. Our case series focuses on the correlation between patients’ exposure tofluorides in air-conditioner production and the subsequent occurrence of OR/OA. Currently,it is uncertain whether these OR/OA were caused by hypersensitivity or irritation.