Chronic lymphocytic thyroiditis and
vitiligo often occur in association and seem to be characterized by a prevalent Th1-driven autoimmune process. The aim of this study is to analyze selected intracellular Τh1 and Th2
cytokines in patients with Hashimoto?s
thyroiditis when associated with non-segmental
vitiligo. We analyzed intracellular
interleukin-2,
interferon-gamma (Τh1) and
interleukin-4 (Th2), in peripheral blood lymphocytes of 23 patients with isolated Hashimoto?s
thyroiditis (group A) and of 11 patients with Hashimoto?s
thyroiditis associated with non-segmental
vitiligo (group B). Peripheral blood lymphocytes were stimulated and incubated with specific
monoclonal antibodies. Intracellular
cytokines were assayed by flow cytometric analysis.
Interleukin-2 and
interferon-gamma positive cells were increased in almost all patients but the median values were similar in patients with isolated Hashimoto?s
thyroiditis and in those with concurrent
vitiligo. In contrast, the number of patients with increased
interleukin-4 positive cells was higher in patients with
thyroiditis and
vitiligo (9/11) than in those with isolated
thyroiditis (2/23; p<0.0001). The median values of
IL-4 positive cells in the two groups confirmed this difference (A: 5.8 percent, vs B: 20.6 percent; p=0.0011). Increased
interleukin-4 positive lymphocytes characterize Hashimoto?s
thyroiditis when associated with non-segmental
vitiligo, suggesting a modified balance from highly prevalent Th1 to mixed Th1/Th2 subset.