Lymphocyte studies in a patient with neurological complications of Behçet's syndrome

We rapport here a case of Behcet's disease presenting with neurological complications who made a remarkable recovery to high dose steroids and azathioprine. Prior to initiation of steroid therapy the percentage of T lymphocytes (OKT3) was low, that of helper T lymphocytes (OKT4) was normal and suppressor T lymphocytes (OKT8) was slightly increased. The OKT4: OKT8 ratio was slightly reduced and the percentage of B lymphocytes was high. With steroid therapy there was an increase in the percentage of OKT3 and fall in the percentages of OKT4 and OKT8 and the OKT4: OKT8 ratio was maintained fairly normal. The percentage of B lymphocytes was reduced. On addition of azathioprine the percentage of OKT3 and OKT8 were substantially increased and the percentage of OKT4 was slightly increased. The net result was a significant reduction in the OKT4: OKT8 ratio. The percentage of B lymphocytes remained normal. On reviewing the absolute counts there was a paradoxical rise in OKT4 and OKT8 a week after high dose steroid therapy due to a substantial rise in the total number of lymphocytes. On reducing the dose of steroids the absolute count of OKT4 and OKT8 decreased in parallel with their percentages. A disparity was noted in the percentage of OKT3 and the sum of the percentages of OKT4 and OKT8, prior to commencement of therapy which was significantly reduced after treatment. It is likely that this disparity is due to the presence of doubly labelled cells (cortical thymocytes) released into circulation prematurely.