CONTRIBUTION OF BIOCHEMISTRY IN THE DIAGN OSIS OF THE NERVOUS STAGE OF HUMAN AFRICAN TRYPANOSOMIASIS

The stage of human African trypanosomiasis (HAT) is important to defin e precisely as far as it is directly related to the type of treatment used. The beginning of the neurological involvement is difficult to fi nd out because there is no known specific clinical or biological sign. This study is trying to look for a precise marker and has been realiz ed in Congo. 70 subjects with parasitologically confirmed HAT and 70 c ontrols are included. The stage of HAT is determined according to the classical definition on the field using the cerebrospinal fluid (CSF) cell count: less than 5 cells/mu l for he first stage (PI), more than 5 cells/mu l for the second stage (P2). The blood analysis has include d : glucose, urea, creatinine, sodium, potassium, calcium, chloride, p hosphorus, uric acid, total bilirubin, unconjugated bilirubin, total c holesterol, triglycerides, total proteins, aspartate aminotransferase, alanine aminotransferase, creatinine phosphokinase, alkaline phosphat ase, gamma-glutamyltransferase, immunoglobulins M and G, C3c fraction of complement, transferrin, seromucoid alpha 1, haptoglobin and albumi n. In CSF we have analyzed IgM, IgG, protein levels and the bloodbrain barrier (BBB) impairment. The comparison between the subjects and hei r controls he subjects in P1 and in P2, the CSF cell count and the oth er CSF alterations show the interest of the IgM level in CSF and the B BB impairment to identify subjects in P2. However there is a low grada tion in the biological disturbances and not a precise threshold point Nevertheless it seems reasonable to raise the CSF cell count level to 20 cells/mu l to define the beginning of the nervous involvement.