Prevalence and Genesis of Dystrophic Amyloid Deposits in Polymyalgia Rheumatica and In Temporal Arteritis

Aim: The aim of this study was to determine the prevalence of amyloid deposits in the temporal arteries, to identify the nature of amyloid in polymyalgia rheumatica (PMR) patients with or without temporal arteritis (TA). Patients and Methods: Surgical biopsy specimens of the temporal artery of 299 patients with PMR were studied. PMR was clinically diagnosed at the National Institute of Rheumatology between 1991 and 2005 according to the criteria of Bird et al. TA was diagnosed histologically, and classified according to Flood et al. Amyloid deposits were identified according to Romhányi by a modified (more sensitive) Congo red staining and confirmed by immunohistochemical techniques, and analysed histochemically according to Bély. The link between amyloidosis and PMR (with or without TA) was analyzed by Pearson’s chi-squared (χ 2) test. Results and Conclusions: Segmental or sectoral TA was associated with PMR in 71 (23.75%) of 299 patients, and was accompanied with amyloid deposits in 18 (25.35% of 71). TA was “classic” in 11 (15.49 %),”atypical” in 44 (61.97 %), and “healed” in 16 (22.54 %) of 71 cases. PMR existed without TA in 228 (76.25%) of 299 patients, and was accompanied with amyloid deposits in 37 (16.23% of 228). PMR and TA are the same disease; TA represents a later and more severe stage of PMR. Amyloid deposits may vary the histology of temporal areteries of PMR patients with or without TA. In our biopsy population the amyloid deposits were exclusively localized, dystrophic and derived from the demaged internal elastic lamellae. Keywords: Polymyalgia rheumatic; temporal arteritis; amyloidosis; Abbreviations: PMR–Polymyalgia rheumatca; TA–Temporal arteritis; Ath–Atherosclerosis; ACR–American College of Rheumatolog