The isolation of dysentery bacilli from the stools of children with clinical dysentery or diarrhea has been investigated from several viewpoints. Some authors have been concerned with the elaboration of new methods or mediums, and others, with the separation of the etiologic agents into groups and subgroups.
Almost all investigators have noted that the organisms are extremely difficult to isolate in a large percentage of cases, that they die in the stools shortly after passage and that many patients who have clinical dysentery, with mucus and blood in the stools, never have positive cultures. Blacklock and Guthrie1 noted, for example, that it became harder to isolate the dysentery bacilli after the acute stages of the disease had passed, but they had been able to obtain a few positive cultures from the intestinal scrapings taken at autopsy. Carter2 noted that positive cultures were obtained from 50 per cent of