[Soluble Interleukin-2 Receptor (sIL-2R): A sensitive biomarker for evaluating disease activity in sarcoidosis]
Valentine Pagis1, Pascal Sève2, Lorna Garnier3
1Département de médecine interne, CHU Lariboisière, AP-HP, université Paris Cité, 75010 Paris, France.
Background:
Sarcoidosis is a systemic granulomatous disease with unpredictable evolution. Current biomarkers, including angiotensin-converting enzyme (ACE) and 1,25-OH vitamin D3, show limited accuracy. The soluble interleukin-2 receptor (sIL2R) reflects T-cell activation and may serve as a sensitive disease activity biomarker.
Objective:
To compare the diagnostic performance of sIL2R with ACE and 1,25-OH vitamin D3 for assessing sarcoidosis activity.
Patients And Methods:
A bicentrique retrospective study was conducted from November 2019 to January 2022 including 103 patients with confirmed sarcoidosis (WASOG criteria). Disease activity was defined by new clinical manifestations or therapy escalation. Serum sIL2R, ACE and 1,25-OH vitamin D3 were compared between active and inactive forms using ROC analysis.
Results:
Among 103 patients (median age 51 years, 54.4% women), 60 (58%) had active disease. sIL2R levels were significantly higher in active patients (2096pg/mL vs 1337pg/mL; P<0.0001). sIL2R showed higher sensitivity (75%) than ACE (54%) and 1,25-OH vitamin D3 (51%) but lower specificity (55.8% vs 75.7% and 81.1%). The combination of sIL2R and 1,25-OH vitamin D3 increased specificity to 94.6% and positive predictive value to 91.3%.
Conclusion:
sIL2R is a sensitive and relevant biomarker for sarcoidosis activity assessment. Combined with 1,25-OH vitamin D3, it enhances diagnostic specificity and may guide disease monitoring.
