Occurrence of Heat Labile Toxins in Closed Intestinal Loops.

Abstract

The report of Williams 1 has stimulated interest in the possibility that heat labile bacterial toxins may play an important rôle in the toxemias of intestinal obstruction and allied disorders. The physical nature of the material obtained from the intestinal tract in these clinical or experimental conditions is such that it is extremely difficult to prepare a sterile filtrate which exhibits anything like the potency of the original material.

Experiments were undertaken to determine whether the fluid from closed intestinal loops of dogs contained appreciable quantities of filterable heat labile toxins. The method of Berkefeld filtration was employed to obtain sterile material for injection into guinea pigs, rabbits and pigeons. A comparison was made of the toxicity of unheated Berkefeld filtrate and fluid heated to 65° C. for one hour and strained through glass wool. Filtration was extremely slow and the quantity of material available from each closed loop usually permitted only one toxicity test to be made.

Intravenous injections of fluids from 7 closed loops were made in rabbits, but because of the frequent complications of intravascular clotting, the results were undecisive. The toxicity of fluids from 13 closed loops was determined for guinea pigs (intraperitoneal administration). In 6 of the 13 cases no definite toxemia occurred with either the heated or unheated fluid, although the maximum amount of available material was used. In 6 cases the administration of the untreated filtrate in amounts of 1.3 to 9 cc. per kilo was fatal to guinea pigs in from 12 to 48 hours. Equivalent amounts of the heated fluid failed to cause marked intoxication or death. In one case both fluids were apparently equally toxic. No difference was noted in the potency of the material from different parts of the intestinal tract or from loops of animals with different survival times.