The study of the distribution of T-lymphocyte sub-populations has revealed some immune characteristics of rheumatoid arthritis (RA) as well as polymyalgia rheumatica (PMR). There is much evidence that the subsets of T-lymphocyte subpopulations are well correlated with the age of the patient and the precise diagnosis of RA and PMR. The aims of the study were to evaluate the absolute number and percentage of T-lymphocyte subpopulation subsets in peripheral blood and their soluble receptors and serum soluble receptors of interleukin-2.
Thirty-six patients with RA were divided into 21 adult-onset RA (AoRA) and 15 elderly-onsets RA (EoRA) patients. They were compared with 48 PMR patients, 21 normal subjects under 45 years and 17 healthy elderly subjects over 65 years. T-lymphocyte subsets were studied by FACSCAN with double stained specific monoclonal antibodies. The EL ISA method was used to determine soluble receptors of CD4+ and CD8+ and IL-2.
The AoRA patients had a significant alteration of T-lymphocyte sub-populations as well as their specific soluble receptors compared to EoRA patients. On the other hand, distribution of T-lymphocyte sub-populations in EoRA patients was quite similar to that in PMR patients.
This method is probably not applicable for daily routine clinical practice but provides some interesting data for differential diagnosis between RA and PMR.