Idiopathic Organizing Pneumonia: A Relapsing Disease

Abstract

Background: Although organizing pneumonia (OP) is a common pathological finding, studies including a substantial number of patients with idiopathic forms from a unique center and a long follow-up are rare. Objectives: To determine patients with cryptogenic forms of organizing pneumonia (COP), in order to characterize their clinical course, to identify predictive factors for relapse and to assess their effect on outcome. Methods: For a 19-year period, all histopathological reports from a community teaching hospital were reviewed, and OP was found in 210 lung specimens belonging to 197 patients. Results: Thirty-three (17%) patients presented cryptogenic forms and 32 of them (97%) responded to steroid therapy. At follow-up, 14 patients presented no relapses (no-relapse group, NR) and 18 (56%) presented relapses (relapsing group, RG) that resolved with ulterior treatment. Multifocal opacities on chest X-ray (RG 83% vs. NR 36%, p = 0.02) appeared to be a predictor for relapse. Patients with relapses showed a shorter time span to chest X-ray normalization (RG 8 ± 8 weeks vs. NR 13 ± 9 weeks, p = 0.09) that became significant in patients with 3 or more relapses (multiple-relapse group, MR, 4 ± 2 weeks vs. NR 13 ± 9 weeks, p < 0.04). Although the initial prednisone dose was similar in patients with relapsing forms, its maintenance was shorter than in patients without relapses, showing a trend to significance (RG 4 ± 3 weeks, NR 7 ± 6 weeks, p = 0.09). Lower levels of lactate dehydrogenase and γ-glutamyltransferase, although always within the normal range, were found in patients with relapsing forms. Conclusion: COP is a specific but infrequent form of OP with a good response to steroid therapy. Relapses are frequent and typical characteristics of COP which resolved with ulterior treatment. Multifocal opacities on chest X-ray and a shorter maintenance of the initial steroid dose may increase the risk of relapse.

Gastroesophageal Reflux Disease Is a Risk Factor for Severity of Organizing Pneumonia

“…However, there have been very few studies on the precipitating factors [42,43,44,45], and to the best of our knowledge, the hypothesis of a possible link with GERD has never been raised. Relapses in our study were defined as previously in the literature [42,43,45]. In a study of 18 cases of OP, Watanabe et al [42 ]found that the PaO 2 of relapsing patients (55 mm Hg) was significantly lower than that of patients with no relapse (78 mm Hg).…”

“…In our study, the patients in the 2 groups who had undergone pathological examination did not show significant differences with regard to collagen fibrosis. Lastly, Barroso et al [45 ]carried out a 19-year retrospective study of 33 cases of COP. They found that relapse was more common in cases with low levels of liver enzymes and with multifocal opacities, and that there was a tendency to relapse in cases with shorter corticosteroid treatment and rapid radiological recovery.…”

Cryptogenic Organizing Pneumonia with a Rare Radiographic Presentation of a Diffuse Micronodular Pattern Mimicking Miliary Lung Infiltration: A Case Report and Review of the Literature

“…In general, the prognosis of COP is good as most forms of COP will respond very well to steroid regardless of the in ltrative pattern on the imaging, if given promptly. Nevertheless, many patients end up being on a long-term steroid therapy due to a high rate of relapse [14] and up to 73% of the patients with COP would have residual disease seen on follow-up CT. In such cases, the lesions generally resemble a brotic nonspeci c interstitial pneumonia pattern that does not resolve even with complete clinical recovery [15].…”

Successful Treatment of Fibrosing Organising Pneumonia Causing Respiratory Failure with Mycophenolic Acid

“…Rapid and complete recovery is the expected response to corticosteroids in OP [10]. A dose ≥40 mg of prednisone was given, on average, for 7.5 weeks.…”