Interferon-gamma in alopecia areata

Alopecia areata is a common type of hair loss. In clinical practice most patients will present with reversible patchy hair loss whereas others may develop complete baldness. Although the etiopathogenesis of alopecia areata is poorly understood, evidence is accumulating that it can be regarded as a T-cell mediated tissue-restricted autoimmune disease of the hair follicle, especially expressing the T-helper-type 1 cytokines interleukin-1beta, interleukin-2, and interferon-gamma. The aim of the study was to compare the serum levels of interferon-gamma in patients with alopecia areata and the control group and also to investigate the difference between the localized form of the disease with the extensive forms like alopecia totalis (AT) and alopecia universalis (AU). Forty patients with alopecia areata and 20 healthy controls were enrolled in the study. Nineteen patients had localized AA (LAA) and twenty-one patients had AT, AU or AT/AU. The serum levels of interferon-y were measured using enzyme immunoassay techniques. The mean serum IFN-gamma level in AA patients (n = 40) was 14.25 +/- 8.76 pg/mL (mean +/- SD), whereas that of LAA (n = 19) or extensive (AT, AU or AT/AU) (n = 21) was 13.45 +/- 6.75 pg/mL or 14.98 +/- 10.37 pg/mL, respectively. The mean serum IFN-gamma level in controls was 9.95 +/- 2.6 pg/mL. Serum levels of IFN-gamma in patients with AA were significantly higher than those in controls (p < 0.05). Significant difference was observed in serum levels of IFN-y between patients with LAA and control group (p < 0.05). Serum levels of IFN-gamma in patients with AT, AU or AT/AU were significantly higher than those in controls (p < 0.05). There was no significant difference in levels of IFN-gamma between patients with LAA and extensive group (p > 0. 05). We conclude that the elevated serum levels of IFN-gamma may reflect the inflammatory symptoms in AA, especially in the extensive form and that control of IFN-gamma production may be important to management of this disease. And also the measurement of serum IFN-gamma in patients with AA may be useful in discriminating those likely to progress to AU from the remaining LAA, or as a prognostic indicator.