The effects of intravenous pulse methylprednisolone on immunological and inflammatory processes in ankylosing spondylitis.

Acute phase reactants, serum immunoglobulins and immune complexes and T cell function were measured in eight patients with active ankylosing spondylitis (AS) before and up to 3 months after three pulses of 1 g methylprednisolone. There was a two stage effect. The first stage was an early anti-inflammatory event with a fall in clinical disease activity mirrored by changes in acute phase reactants particularly prealbumin. The second stage occurred later and was an immunological event with a fall in serum IgA and IgG and a rise in mitogenic response, mixed lymphocyte response and delayed cutaneous hypersensitivity. Most of these changes returned towards pre-treatment levels by 3 months. This study has shown that pulse methylprednisolone has an immediate anti-inflammatory and a prolonged immunological effect in AS.