Background: Sarcoidosis is a chamaleontic disease. While most cases are self-limiting, it is important to identify at baseline patients who may require systemic therapy.

Aim: to identify potential predictors of need for treatment in patients with sarcoidosis.

Methods: between March 2017 and January 2023, 200 patients were evaluated in our Sarcoidosis Clinic and 142 were enrolled. Clinical, radiological, and serological values at diagnosis were retrospectively collected. Patients were divided in treated (n=91) and untreated (n=51). The need for second-line agents was then investigated. 

Results: treated (n=91) and untreated (n=51) patients were similar for age (p=0.22), gender (p=0.72), and smoking history (p=0.39). However, treated patients complained more frequently of fatigue [22(24%)vs.3(6%);p=0.006], and had more often extrapulmonary disease [47(52%)vs.13(25%);p=0.003]; lower FVC%pred [95(35?165)vs.107(76?145);p=0.002], and higher prevalence of parenchymal involvement (without lymph node enlargement) on baseline CT scan [19(21%)vs.3(6%);p=0.03]. Patients treated with second-line agents had higher ACE levels [67(9?273)vs.42(5?280);p=0.03] and higher monocyte count [0.64(0.26?3.7)vs.0.53(0.05?1.43); p=0.008]. On multivariable analysis, the presence of extrapulmonary disease [OR:4.23, 95%CI(1.51?11.9);p=0.006] and isolated parenchymal involvement on baseline CT scan [OR:6.5, 95%CI(1.16?35.44);p=0.03] remained independent predictors of need for treatment.

Conclusion: extrapulmonary disease and isolated parenchymal involvement at baseline are independent predictors of treatment in patients with sarcoidosis. Patients with higher ACE values and monocyte count are more likely to require a second-line treatment.