Beta 2-microglobulin levels in homosexual men in Johannesburg, South Africa.

Abstract

The studys purpose was to measure the beta 2-microglobulin levels in normal homosexual men. The subjects had defective cell mediated immunity (CMI) as determined by absent delayed hypersensitivity skin test reversed helper: supressor T-lymphocyte ratios and decreased lymphocyte proliferative activity in response to mitogen stimulation. They also had chronic lymphadenopathy. Elevated levels of serum beta 2-microglobulin were recently reported in patients with AIDS and in patients at high risk for AIDS. The Pharmacia beta 2-micro RIA test was used to measure the beta 2-microglobulin. A significantly higher mean level of beta 2-microglobulin was found in confirmed AIDS cases patients with defective CMI and those with chronic lymphadenopathy than in homosexual men with normal CMI and the age-matched controls (P < 0.001). Additionally a significant difference was found between patients with chronic lymphadenopathy showing normal CMI compared with those showing defective CMI (P < 0.001). No difference was found between the age-matched controls and the homosexual men with normal CMI. Of the 93 cases where CMI was investigated 71% of the homosexual men with defective CMI had elevated levels of beta 2-microglobulin (normal limit was 3.0 mg/L); 9% of the homosexual men with normal CMI had elevated levels. Elevated levels of serum beta 2-microglobulin may be a useful marker in assessing lymphoid reactivity in AIDS. The mechanism of the increase is not clear.