Summary of the results of investigations performed
| Test | Subjects tested | Abnormal results | Other information |
| IgG, IgA, IgM | 41/47 (87) | 5/41 (12) | Low IgG, 0.2 g·L−1 below normal (n = 3) |
| Low IgM, 0.2 g·L−1 below normal (n = 2) | |||
| IgG subclasses | 11/47 (23) | 3/33 (9) | All three abnormal results were normal when repeated |
| Sweat test | 30/47 (64) | 0/30 (0) | Equivocal 1/30 (3%) |
| HRCT scan | 29/47 (62) | 15/29 (52) | |
| pH study | 37/47 (79) | 25/37 (68) | Unsuccessful 2/37 (5) |
| Cilia | 34/47 (72) | 0/34 (0) | Nude epithelium 8/34 (24) |
| FOB# | 47/47 (100) | 37/47 (78) | |
| BAL: any result¶ | 44/47 (94) | 39/44 (89) | |
| BAL culture+ | 44/47 (94) | 19/44 (43) | |
| BAL fat-laden macrophages | 44/47 (93) | 33/44 (75) | Score: mild (n = 23), moderate (n = 8) and severe (n = 2) |
| BAL inflammation | 37/47 (79) | 24/37 (65) | Score: eosinophilia (n = 4), neutrophilia (n = 16), combined (n = 4) |
| EB eosinophilic inflammation | 36/47 (77) | 16/36 (44) | Score: 0 (n = 20), 1 (n = 6), 2 (n = 6), 3 (n = 3), 5 (n = 1) |
| EB RBM thickening | 35/47 (74) | 10/35 (29) | Score: 0 (n = 2), 1 (n = 23), 2 (n = 9), 3 (n = 1) |
Data are presented as n/n (%). Ig: immunoglobulin; HRCT: high-resolution computed tomography; FOB: fibreoptic bronchoscopy; BAL: bronchoalveolar lavage; EB: endobronchial biopsy; RBM: reticular basement membrane. #: details of abnormalities in the text; ¶: BAL inflammation, fat-laden macrophages or infection; +: BAL with significant bacterial growth.