RESUMEN
CONTEXT: Autoimmune diseases frequently improve during active Cushing's syndrome. Several studies have reported new onset or exacerbation of these conditions upon cortisol normalization. OBJECTIVE: Our objective was to investigate the incidence and clinical characteristics of patients with autoimmune or allergic diseases after Cushing's syndrome remission. METHODS: Consecutive cases of confirmed Cushing's syndrome were characterized. A review of the literature was conducted to identify previous descriptions of immune dysfunction upon remission and evidence of the hypothalamic-pituitary-adrenal axis influence on the immune system. RESULTS: Among 66 patients who achieved Cushing's syndrome remission, the incidence of immune dysfunction was 16.7%, where eight cases (72.7%) were noted for the first time and three (27.3%) were exacerbated. All had an ACTH-dependent cause. Glucocorticoids reduce proinflammatory cytokines and interact with other transcription factors affecting T cell and mast cell survival. CONCLUSION: Hypercortisolism induces a state of immunosuppression. After Cushing's syndrome remission, rebound immunity frequently results in overt conditions extending beyond thyroid dysfunction.
