Background/Purpose: Sarcoidosis is a systemic granulomatous disease that can affect multiple organs, and in particular lung involvements are common and found in more than 90% of the patients [1]. Spontaneous remission is often observed within 2 years [2] and chest radiographic stage, skin involvements, over 40 years old or smoking history are reported as poor prognostic factors in pulmonary salcoidosis [3, 4]. However, there were no comprehensive reports of factors of relapse or exacerbation and characteristics of favorable patients without treatment in the long-term period more than 2 years. Aim of study is to identify prognostic factors for relapse or exacerbation in patients with pulmonary sarcoidosis in the long-term period.

Methods: Ninety-three patients who had visited at our division of Hachinohe Red Cross Hospital between January 2007 and December 2016 and clinically diagnosed as pulmonary sarcoidosis, were enrolled. They were divided into two groups, which presented relapse or exacerbation, and spontaneous remission. Clinical, laboratory and imaging data were collected from medical records and statistically analyzed.

Results: In 93 patients, 77% were women and mean age at diagnosis was 50.1 ± 16.6 years old. Mean observation period was 9.9 ± 8.8 years. Numbers of patients who had previously reported short-term prognostic factors are following: chest radiographic stage (Stage 0: n=3, Stage Ⅰ: n=29, Stage Ⅱ: n=36, Stage Ⅲ: n=15, Stage Ⅳ: n=10), skin involvement (n=9), age over 40 years old (n=66), and smoking history (n=31). Overall relapse or exacerbation rate was 18.3% (n=17) and mean period to relapse or exacerbation was 8.5 ± 8.4 years. Then, we purified 64 patients who were observed for more than 5 years, and relapse or exacerbation was found in 7 patients. When compared characteristics at diagnosis between two groups, decrease of peripheral number of lymphocytes, frequency of bilateral hilar lymphadenopathy, or less than 3.5 in the ratio of CD4/CD8 in bronchoalveolar lavage fluid (BALF) were significantly highlighted in relapse or exacerbation group (P=0.019, 0.042, and 0.018, respectively).

Conclusion: Our long-term observational cohort study identified incidence rate and unique prongostic factors of relapse or exacerbation in patients with pulmonary sarcoidosis. This information could contibute to more appropriate medical administration in long term period.

References: [1] Br. J. Dis. Chest. 1976; 70:206–210, [2] Dan. Bull. Med. 1982; 29:27–32, [3] Br. Med. J. 1961; 2:1165–1172, [4] Chest. 2006; 130:1851-6.

ACR Meeting Abstracts - https://acrabstracts.org/abstract/identification-of-long-term-prognostic-factors-for-relapse-or-exacerbation-in-patients-with-pulmonary-sarcoidosis-a-single-center-long-term-observational-cohort-study/