Open AccessHigh‐resolution computed tomographic characteristics in acute farmer′s lung and in its follow‐up
Author(s) -
Cormier Y.,
Brown M.,
Worthy S,
Racine G,
Müller N.l
Publication year - 2000
Publication title -
european respiratory journal
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 4.021
H-Index - 241
eISSN - 1399-3003
pISSN - 0903-1936
DOI - 10.1034/j.1399-3003.2000.16a10.x
Subject(s) - medicine , high resolution computed tomography , computed tomography , lung , radiology , ex vivo , lung fibrosis , mediastinal lymphadenopathy , hypersensitivity pneumonitis , high resolution , computed tomographic , fibrosis , pulmonary fibrosis , nuclear medicine , pathology , biochemistry , chemistry , remote sensing , in vitro , geology
High resolution computed tomography (HRCT) scans are increasingly used in hypersensitivity pneumonitis (HP). This study looked at HRCT findings at different phases of farmer′s lung (FL), a common form of HP. A cross sectional analysis of 95 HRCT scans of FL cases (20 acute, 75 with a history of FL, 48 still in contact (Ex +) (dairy farm), and 27 who had ceased contact (Ex‐)) was made. All scans were read independently by two, and if needed by three, radiologists blinded to the category. The lungs were divided into six regions (fives lobes + lingula), and read for attenuation/mosaic, ground‐glass, micronodules, fibrosis, and emphysema. A score of 0–3 was given for each region and each variable: 0 = absence, 1 =<25% of the surface, 2 = 25–50%, 3 =>50%. Mediastinal lymphadenopathy was also noted. Ground glass, predominating in the lower lobes, was the most frequent feature in the acute and Ex+ cases. Other abnormalities had no preferential distribution. Ex+ had more ground‐glass than the Ex‐ (p=0.0025). Emphysema was more frequently seen than interstitial fibrosis (p=0.004). Mediastinal lymphadenopathy was present in 26 cases (9 acute, 10 Ex+ and 7 Ex‐). In conclusion, in farmer′s lung: 1) ground‐glass predominates in the lower lobes while the other abnormalities have no anatomic predilection; 2) contact avoidance allows a better resolution of computed tomography abnormalities than continued exposure; 3) emphysema is a more frequent finding than interstitial fibrosis; and 4) the presence of mediastinal lymphadenopathy has no negative diagnostic value.