We investigated the immunoglobulin and haematological status of 35 human African trypanosomiasis (HAT) positive subjects and 15 control volunteers in Abraka, Nigeria. For weakly positive (1866.33±5.51mg/dl) and moderately positive (1874.50±4.35mg/dl) HAT volunteers, the IgG levels were higher than the control subjects (p<0.0001). Also, strongly positive (3926.33±5.77mg/dl) individuals were higher in IgG levels than the control (944.66±10.51mg/dl) subjects (p<0.0001). Concentrations of IgM for strongly positive (485.66±3.05mg/dl) subjects were higher than the control (107.66±6.81mg/dl) individuals (p<0.0001). The levels of IgA between early stage (222.66±18.5mg/dl) and late stage (480.33±2.51mg/dl) were not significant (p>0.05). In all, mean differences in the IgA levels of seropositive HAT volunteers and control subjects were not significant (p>0.05).The concentrations of IgG between HAT late stage (3927±3.6mg/dl) volunteers were higher than individuals in the early stage (1871±4.3mg/dl) at p<0.0001. Similarly, IgM levels among volunteers were higher for late stage (480.33±2.51mg/dl) than individuals with the early stage (135.66±2.08mg/dl) of HAT (p<0.0001). We observed that the volunteers with late stage were severely anaemic (82 x 109 g/dL) while early stage subjects were mildly anaemic (108 x 109g/dL). Also, individuals with late stage of HAT showed normocystic hypochromic anaemia. In addition, lower counts of white blood cells (WBC) were observed for HAT late stage, an indication of the condition of leucopinae. Furthermore, mean platelet counts for late stage (154 x 109cells/L) and early stage (178 x 109cells/L) of HAT were more depressed than their control subject (205 x 109cells/L). Conclusively, the indices of elevated serum IgM, IgG could be biomarkers of suspicion of HAT infection. Also, leucopinae and anaemia are complications of HAT infections in our locality.
