Fasting hyperglycaemia and impaired oral glucose tolerance in acute Trypanosoma brucei infection of rats

Trypanosoma brucei (Federe strain) produced all acute infection in rats given 10(6) parasites intraperitoneally. Parasitaemia, which first appeared at 2 days post-infection (pi), was heavy from day 5 until death at 8 to 12 days pi. The fasting tail-blood glucose (FBG) concentrations in the infected rats increased significantly (P0.05) from 2.73+/-0.14 mmol/l on day 0 pi to 6.21+/-0.16 mmol/l and 5.93+/-0.33 mmol/l on days 5 and 8, respectively. However, the values had decreased in most of the rats on day 11 pi, at which time 4 out of 12 had less than 0.5 mmol/l. The mean FBG showed a quadratic relationship with the duration of infection and the fitted curve had a high goodness of fit (r2=0.98). Oral glucose tolerance was impaired in the infected rats on days 5, 8 and 11 pi. Tail-blood glucose concentration was determined 2 h after the intake of glucose (1.0 g/kg). The mean percentage increases in blood glucose from the FBG concentrations were significantly (P0.05) higher in the infected than in uninfected rats. There was a positive correlation (r=1.0) between the mean percentage increases and the duration of infection. It seems probable, therefore, that the delivery of glucose into the tissues was reduced, with other metabolic implications likely to affect the pathogenesis of the disease.