O Filtrado do Mycobacterium de Stefansky na Lepra Murina

Abstract

A filterable granular form of M. Stefanski and possibly Mycobateria exists. Many bacilli pass through bacteriological filters but in this paper we are interested only in the finelly granular part of this germs. An existence of this filterable form is shown in M. tuberculosis, as an instance, by the lesion produced and which have their own pathology. In human leprosy this form seems responsible for certain phenomena seen in incipient cases but-there is no definite proof. In murine leprcsy we have shown its existence by filtering in Stiez a leproma suspension preserved in glycerine and distilled water, in equal parts, which was inoculated in rats. Glycerine acts in such a manner on the virulence of the bacilli that in material kept for 30 days, the washed germs which were reduced as much as possible to a non filterable form and were then inoculated in rats were scon destroyed. On the othe hand animais injected with the filtrate showed in most cases great bacilli poliferation. The filtratesalso resist more to ultraviolet irradiation than washed bacilli. For this reasons given above it is not possible doubt the existence on M. Stefanski of a filteraible infrancicrobian form. In another series of experiments we have already show that this type of germ is eliminated by the rats nose previously inoculated with filtrates even in the absence of organized bacilli. In an effort to know what function these fllterable elements have, we observed that, when inoculate until 60 days before m., injection of an active leproma suspension, they gave higher infectivity and seemed to have a "sensitized action". We observed too that an interval of 90 days was made the germ dispersion was smaller than ln the control lot, being however of greater volume the inicial leproma. with the inoculation of irradiated filtrate a similar fact was observed but toxidity was smaller. With this data we tried to observe how the infection would process. We inoculated filtrate of M. of Stefanski in a series of rats after 10 days washed bacilli. Controls received only washed bacilli. At the end of six months dispersion of germs was observed and the first appearence of progressive leprosy in the first lot, in the second lot nothing or very few showed symptoms. There is an impressian that leprosy appears in two phases: a) infection by filterable elements (preparatory elements) and b) infection by the organized bacilli. Definitive conclusions can, however, only be reached when more numerous investigations are made over a lenghtier spam of time.