Clinical and immunologic characteristics of nonhematologic autoimmune disorders in chronic lymphocytic leukemia

Background: Autoimmune disorders (AIDs) are frequent in patients with chronic lymphocytic leukemia (CLL). There is little information on the clinical characteristics and pathogenesis of nonhematologic AIDs in patients with CLL, although both entities present immunologic alterations in their clinical onset. Methods: This single-center series included 907 patients with CLL who had a median follow-up of 6.6 years (range, 0.1-36.4 years). Results: In total, 156 patients developed an AID, including 99 patients (10.9%) with nonhematologic AIDs, 46 (5.1%) with autoimmune cytopenia (AIC), and 11 (1.2%) with both; autoimmune hypothyroidism and psoriasis were the most frequent AIDs. Patients with nonhematologic AIDs had low-risk genetic features and were related to a better time to first treatment than patients with AIC (13.8 vs. 5.5 years; p <.001). Patients with both CLL and psoriasis had the lowest risk of progression. The authors performed a T-cell/natural killer-cell and cytokine assessment among patients who had CLL with and without psoriasis. An unsupervised hierarchical clustering revealed a distinct cluster characterized by an expansion of T-helper 17 cells, T-regulatory cells, interleukin-17F, and interleukin-23. Conclusions: The current findings suggest that nonhematologic AIDs are prevalent in patients with CLL, and these patients have a better prognosis than patients who have AIC. The expansion of interleukin-17F-producing cells in patients with psoriasis may explain their good prognosis.