Experimental therapy in clonorchis infections.

Abstract

Utilizing the method worked out by Faust and Khaw, as presented in the preceding paper, for estimating the number of Clonorchis worms present in the bile passages of laboratory animals, on the basis of the average daily egg count from weighed samples of stools, the authors have tested the effect of gentian violet and mercurochrome on cats and dogs. Both mercuro-chrome and gentian violet, administered orally in the form of salol coated pills, have a direct effect on egg-production in Clonorchis, in that they greatly accelerate the speed of production. Under these conditions eggs are immature when laid and are frequently imperfect and non-viable.

This phenomenon of hyperproductivity of Clonorchis ova after therapeusis is not directly dependent on the clonorchicidal effect of the dye. In the mercurochrome series living worms with empty uteri were recovered some days after hyperproduction of ova had been observed, in numbers consistent with the previous worm estimate. This appears to refute the idea that the immature eggs in the feces are due to the disintegration of dead worms.

Mercurochrome in doses lethal to the host has no apparent clonorchicidal value. On the other hand tolerated doses of gentian violet will apparently cause the death of all Clonorchis worms in those parts of the bile passages which can be reached by the dye. In light infections this may constitute the entire number of worms (complete cures), as determined by autopsy findings. In heavy infections eradication up to 90 per cent or more of the worms can be secured whenever the host is able to tolerate intensive treatment.

Oral administration of gentian violet in small doses requires prolonged treatment to secure similar results. Doses of gentian violet (Griühler) administered peros to cats and dogs, within the limit of tolerance as determined by continued good appetite, absence of nausea or emesis, and sustained or increased body weight, consist of not more than 35 mg. per diem per kilo of body weight are toxic to the host and cause death if repeated frequently.