PO16 - Looking at the Both Sides of the Coin: A Pooled Analysis of Case Reports with Possible Silicosarcoidosis
Grgur Salai (Croatia)1; Jasna Tekavec-Trkanjec (Croatia)1; Luka Manojlović (Croatia)2; Nevenka Piskač Živković (Croatia)1 3;
1 - Department of Pulmonology, University Hospital Dubrava, Zagreb, Croatia; 2 - Department of Pathology and Cytology, University Hospital Dubrava, Zagreb, Croatia; 3 - Faculty of Pharmacy and Biochemistry, University of Zagreb, Zagreb, Croatia;
Keywords: silicosarcoidosis; respirable crystalline silica; occupational lung disease;
Select the theme: Challenges in Sarcoidosis Diagnosis and Staging
Type: Original Papers
Presentation: Poster Presentation

Introduction: Silicosarcoidosis is a newly coined term by Hua et al. which describes patients with features of both silicosis and pulmonary sarcoidosis. To date, the data on silicosarcoidosis is scarce.

Objectives: Aiming to increase the body of knowledge on silicosarcoidosis, we conducted a pooled analysis of available case studies on patients deemed to have possible silicosarcoidosis.

Materials and Methods: This study pooled data from published case series on silicosarcoidosis, cases from our center (publication in preparation) and case reports from MEDLINE found by systematic search that completed the following inclusion criteria: occupational exposure to respirable crystalline silica, pulmonary manifestations, histological presence of non-caseating granulomas and either silicotic nodules or birefringent particles (Figure 1). Cases with talcosis, concomitant aluminosis or mixed-dust pneumoconiosis cases were excluded. Findings were reported with percentage of missing data (MD).

Results: We identified a total of 50 patients with possible silicosarcoidosis from 10 countries (Figure 1). All participants were male. The median age at diagnosis was 39 years(Q1-Q3=31.5-49; MD 82%). The median occupational exposure at diagnosis was 20 years(Q1-Q3=9.5-27.5; MD 26%) (Figure 2). Information regarding bronchoalveolar lavage(BAL) was available for 10 patients, of which 8 had a lymphocyte predominant BAL and 2 had macrophage-predominant BAL with elevated neutrophil counts. Data regarding therapy and its outcome was available for 10(20%) individuals, of which 7 showed improvement, 2 worsened in spite of therapy and 1 patient had no change in imaging or symptoms.

Conclusions: Silicosarcoidosis patients have potential benefit from treatment, but also from occupation change and financial compensation should be recommended to the governing bodies. Since no diagnostic criteria exist and this retrospective research analyzed case reports, it is possible that not all cases have silicosarcoidosis and that some cases were omitted. The missing data might be mitigated by contacting authors of included cases and discussing the proposed the diagnosis of silicarcoidosis in the future.

Figure 1. Pooling strategy included pooling of data from the original publication by Hua et al. (N=35) and the accompanying publication by Leite et al. with patients classified as silicosarcoidosis (N=4). Additionally, N=2 patients from our centre diagnosed with silicosarcoidosis were included (publication in preparation). We found N=9 more cases by identifying 7 case studies as a result of systematically searching MEDLINE (Pubmed) with the following search strategy: “(granuloma) AND (((silicosis) OR (silica) OR (silicate))“, filtered for case reports. The search yielded 230 results, of which 4 potential case reports were not accesible.Figure 2. Distribution of patients per occupational groups (as originally stratified by Hua et al.) with age in years and exposure in working-years. As the majority of data is missing, the percentage of missing data (MD) is reported for each variable. Q1 – first quartile, Q3 – third quartile.