Airway obstruction in rheumatoid arthritis: CT manifestations, correlated with pulmonary function testing.
In the present study, the signs of airflow obstruction on inspiratory and expiratory CT scans in 45 patients with rheumatoid arthritis were investigated. Radiologic findings were evaluated and correlated with the clinical data, which included rheumatoid factors and pulmonary function tests results. A lung biopsy was performed in five patients. The pattern of CT findings was as follows: infiltrative (n=15), obstructive (n=12), mixed (infiltrative and obstructive; n=10), other complicating diseases (n=7), and normal (n=1). The rheumatologic factor between patients with bronchial wall thickenings and patients without thickenings was significantly different (p=0.009). The forced expiratory flow rate between 25% and 75% of the vital capacity (FEF(25-75%)) was significantly more reduced in patients with interlobular septal thickenings than in patients without these thickenings. The patients with mosaic attenuation had significantly lower mean values of FEF(25-75% ) (p=0.001) and a lower peak expiratory flow (p=0.003) than patients without mosaic attenuation. On expiratory scans, the mean air-trapping score was 21%. These air-trapping scores were found to be well correlated with FEV1/FVC (r=0.230, p=0.0452), and FEF25-75% (r=-0.63, p= 0.05). It is widely known that a relatively higher percentage of mosaic attenuation with air-trapping and a good correlation between these and functional values contribute to the detection of early airway obstruction in patients with rheumatoid arthritis, and even in patients with infiltrative lung disease only.
Chung
Myung Hee
MH
Department of Radiology, Holy Family Hospital, The Catholic University of Korea, 2, Sosa-dong, Wonmi-gu, Pucheon-si, Kyunggi-do, Korea. mhchung@catholic.ac.kr
Lee
Hae Giu
HG
Kwon
Soon Suck
SS
Park
Seog Hee
SH
Kim
Ki Joon
KJ
Jung
Jung Im
JI
Sung
Mi Sook
MS
Yoo
Won Jong
WJ
D000293:Adolescent; D000328:Adult; D000368:Aged; D000402:Airway Obstruction / Q000000981:diagnostic imaging* / Q000453:epidemiology* / Q000503:physiopathology; D001172:Arthritis, Rheumatoid / Q000453:epidemiology*; D005260:Female; D005540:Forced Expiratory Flow Rates; D006801:Humans; D015994:Incidence; D008297:Male; D008875:Middle Aged; D010366:Peak Expiratory Flow Rate; D012129:Respiratory Function Tests; D014057:Tomography, X-Ray Computed; D014797:Vital Capacity