Microheterogeneity of acute phase proteins in the differentiation of polymyalgia rheumatica from polymyositis
Pawlowski, T.; Aeschlimann, A.; Kahn, M.F.; Vaith, P.; Mackiewicz, S.H.; Mueller, W.
Journal of Rheumatology 17(9): 1187-1192
1990
ISSN/ISBN: 0315-162X PMID: 1705291 Document Number: 354762
We studied an .alpha.-1-acid glycoprotein (AGP) and an .alpha.-1-antichymotrypsin (ACHT) microheterogeneity in sera of patients with polymyalgia rheumatica (PMR), giant cell arteritis (GCA/PMR), polymyositis/dermatomyositis (PM/DM) and healthy individuals by affinity electrophoresis with concanavalin A (Con-A) as the ligand. Our results are expressed as reactivity coefficients. The mean of AGP reactivity coefficients (AG-RC .+-. SD) in PMR (0.92 .+-. 0.17) and GCA/PMR (0.91 .+-. 0.12) were significantly lower compared with the mean Ag-RC in patients with PM/DM (1.48 .+-. 0.52) as well as in healthy individuals (1.34 .+-. 0.9). Moreover, and additional microheterogeneous form of AGP was noted in patients with PM/DM. In parallel, we also found that the mean of ACHT reactivity coefficients (AC-RC .+-. SD) were lower in patients with PMR (2.94 .+-. 1.24) and GCA/PMR (1.66 .+-. 0.16) compared with healthy individuals (3.92 .+-. 1.17). The mean of AC-RC in patients with PMDM (6.74 .+-. 4.35) was significantly higher than in patients with PMR and GCA/PMR as well as in healthy individuals. Our results show that the changes in reactivity of AGP and ACTH with Con-A are useful diagnostic markers for the differentiation of PMR and GC/PMR from PM/DM.