Polymyalgia rheumatica and temporal arteritis: the endocrine relations and the pathogenesis. Review

Polymyalgia rheumatica (PMR) and giant cell or temporal arteritis (TA) are related chronic inflammatory conditions which typically affect the aged subjects. Typical features of PMR include general symptoms of inflammation as well as severe muscle pain in shoulder and pelvic girdle. The manifestation of TA depends on localization of affected artery, usually branch vessels of the aortic arch. Etiology of PMR and TA remains unclear. The association with HLA system and characteristics of the inflammatory response are discussed in this paper. Age related changes in neuroendocrine system could also represent a pathogenic factor in genetically disposed individuals. Complex bi-directional neuroendocrine-immune relations are further modified by ongoing chronic inflammation. Good clinical response to glucocorticoids in PMR patients supports the assumption that the actual levels of cortisol are lower than would be expected during ongoing inflammation. Moreover, decreased levels of adrenal androgens have been observed in PMR and thus possible adrenal androgens supplementation during glucocorticoid treatment sketches new prospects for the treatment of PMR and TA.