IGHE and bronchial disorder: Baxter et al. [6] proposed a classification for Aspergillus lung disease in CF based on microbiology (culture, sputum galactomannan, Aspergillus real-time polymerase chain reaction) and serology (A. fumigatus-specific IgE and IgG), which defined four clinical groups: allergic bronchopulmonary aspergillosis (ABPA), Aspergillus sensitisation, Aspergillus colonisation and Aspergillus bronchitis.