Cell-mediated immunity in amoebic liver abscess.

Cell-mediated immunity studies were carried out in 26 cases of amoebic liver abscess by the leucocyte migration inhibition test and in 23 cases by T-cell counting. The tests were repeated after treatment and clinical recovery in 20 and 18 cases respectively. In addition, the leucocyte migration inhibition test was performed on 20 normal healthy controls and 11 Entamoeba histolytica cyst passers, and T-cell counting was carried out on 18 normal healthy controls and nine E. histolytica passers. The results of the present study show a transient state of immunodepression which may help E. histolytica to evade the defence mechanism of the host, and thereby invade target cells and produce liver abscess. This immune response is reversed after treatment and clinical recovery.