Trypanosoma rhodesiense

Melarsoprol is a trivalent arsenical with activity against East African and West African tiypanosomiasis. It is the dmg of choice in the case of Trypanosoma rhodesiense infection with nervons system involvement (stage II disease) and in stage I patients refractory or intolerant to snramin and pentamidine. Melarsoprol administered intravenonsly can canse a reactive encephalopathy, with a clinical pictnre consisting of high fever, headache, tremor, convnlsions, and on occasion coma and death. The incidence of arsenic encephalopathy varies from 3 to 18% in varions series (SEDA-12, 708) (1). 

Ryley, J. F. (1962) Studies on the metabolism of protozoa. 9. Comparative metabolism of the culture and bloodstream forms of Trypanosoma rhodesiense. Biochem. J. 85 211-223. 

Fish, W. R., Looker, D. L., Marr, J. J. and Berens, R. L. (1982) Purine metabolism in the bloodstream forms of Trypanosoma gambiense and Trypanosoma rhodesiense. Biochim. Biophys. Acta 719 223-231. 

Dixon, H. and Williamson, J. (1970) The lipid composition of blood and culture forms of Trypanosoma lewisi and Trypanosoma rhodesiense compared with that of their environment Comp. Biochem. Physiol. 33 111-128. 

The following anti-trypanosomal drugs bind irreversibly to, and disintegrate, the kinetoplast of Trypanosoma rhodesiense (in the mouse) without any effect on the cell s nucleus diminazine, ethidium, pentamidine, hydroxystilbamidine, and trypaflavine (Macadam and Williamson, 1972). The lack of a histone covering over the kinetoplast makes it more vulnerable than the nucleus to these drugs (Steinert, 1965). In place of mitochondria, some protozoa have hydrogeno-somes in which ferredoxin-activated enzymes, which convert pyruvate to acetyl-CoA, are selectively vulnerable to metronidazole. 

Aboko-Cole, G. F. and Lee, C. M. (1974) Interaction of nutrition and infection effect of folic acid deficiency on resistance to Trypanosoma Lewis and Trypanosoma Rhodesiense, Int. J. Biochem., 5 693. 

Suramin is used primarily to treat African trypanosomiasis, for which it is the drug of choice. It is effective in treating disease caused by Trypanosoma gam-biense and T. rhodesiense but not T. cruzi (Chagas ... 

Baltz T, Baltz D, Giroud C, Crockett J. Cultivation in a semi-defined medium of animal infective forms of Trypanosoma brucei T. equiperdum, I evansi, T. rhodesiense and T. gambiense. EMBO J 1985 4 1273-1277. 

FIGURE 1 Trypanosoma brucei rhodesiense, one of several trypanosomes known to cause African sleeping sickness. 

Alkaloids isolated from Crinum kirkii, from Kenya, have been investigated in vitro against Trypanosoma brucci rhodesiense and T. cruci. The alkaloids... 

African sleeping sickness Trypanosoma brucei-gambknse, T.b. rhodesiense Suramine, pentamidine, DFMO (for early stage) and tryparsamide, Mel B, Mel W, melarsen sodium, nitrofura-zone (for late stage of the disease with CNS involvement). 

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