Acute exacerbation of interstitial pneumonia associated with collagen vascular diseases.
BACKGROUND
Acute exacerbation (AE) is currently established as a distinct condition with acute deterioration of respiratory status in idiopathic pulmonary fibrosis (IPF). Recently, several studies have reported that AE also occurred in interstitial pneumonias other than IPF, such as collagen vascular disease-associated interstitial pneumonia (CVD-IP). However, the incidence of AE in CVD-IP and its clinical characteristics remain to be fully determined. This study was conducted to elucidate cumulative incidence of AE in CVD-IP and its clinical features.


METHODS
We reviewed 83 biopsy-proven CVD-IP patients, estimated cumulative incidence of AE, and examined its clinical characteristics.


RESULTS
Among 83 CVD-IP patients, six patients with a mean age of 65.7 years developed AE (overall incidence, 7.2%; 1-year incidence, 1.25%). Underlying CVDs included rheumatoid arthritis (RA) (n=5; overall incidence, 20.0%) and primary Sjögren syndrome (n=1; overall incidence, 5.9%). Patients with AE showed acute respiratory deterioration with severe hypoxemia (mean PaO(2)/FiO(2) ratio, 131). Radiologically, ground-glass opacity was superimposed on the underlying reticular abnormalities. Preexisting histological patterns included three usual interstitial pneumonia (UIP) and two non-specific interstitial pneumonia (NSIP). Five (83.3%) of six patients died of respiratory failure despite intensive therapy. Univariate Cox's proportional hazards analysis showed that age and RA diagnosis were significantly associated with AE. Multivariate Cox's proportional hazards analysis indicated that age was an independent significant factor predicting AE.


CONCLUSIONS
These data suggest that AE can occur in CVD-IP, and this condition is closely similar to that of IPF with poor prognosis. AE is most common in RA, and associated with higher ages.
Suda
Takafumi
T
2nd Division, Department of Internal Medicine, Hamamatsu University School of Medicine, 1-20-1 Handayama, Hamamatsu, Shizuoka 431-3192, Japan. suda@hama-med.ac.jp
Kaida
Yusuke
Y
Nakamura
Yutaro
Y
Enomoto
Noriyuki
N
Fujisawa
Tomoyuki
T
Imokawa
Shiro
S
Hashizume
Hideo
H
Naito
Tateaki
T
Hashimoto
Dai
D
Takehara
Yasuo
Y
Inui
Naoki
N
Nakamura
Hirotoshi
H
Colby
Thomas V
TV
Chida
Kingo
K
D000208:Acute Disease; D000367:Age Factors; D000368:Aged; D000893:Anti-Inflammatory Agents / Q000627:therapeutic use; D001706:Biopsy; D018893:Bronchoalveolar Lavage; D003240:Connective Tissue Diseases / Q000150:complications*; D003520:Cyclophosphamide / Q000627:therapeutic use; D018450:Disease Progression; D005260:Female; D006801:Humans; D007166:Immunosuppressive Agents / Q000627:therapeutic use; D015994:Incidence; D008168:Lung / Q000473:pathology; D017563:Lung Diseases, Interstitial / Q000175:diagnosis / Q000503:physiopathology* / Q000628:therapy; D008297:Male; D008775:Methylprednisolone / Q000627:therapeutic use; D008875:Middle Aged; D016016:Proportional Hazards Models; D012131:Respiratory Insufficiency / Q000209:etiology; D012189:Retrospective Studies; D012307:Risk Factors; D014057:Tomography, X-Ray Computed; D014652:Vascular Diseases / Q000150:complications*
D000893:Anti-Inflammatory Agents; D007166:Immunosuppressive Agents; D003520:Cyclophosphamide; D008775:Methylprednisolone