TUNEVALL AND LINDNER 

 DISCUSSION 



Observations of other investigators, corroborated in the present 

 study by findings to be discussed below, make us accept the view of 

 the intestinal flora as the source of endogeneous bacteremia in pro- 

 longed hypothermia. The ability of intestinal bacteria to invade the 

 rest of the body during the hypothermic state might be due to a 

 change of this flora itself. The absence of food intake, the slowing 

 down of intestinal motility, and the low temperature seem likely to 

 effect such a change. However, as shown in Figure 4, no major alter- 

 ation of the composition occurred. It must be stated in this connec- 

 tion that our studies were restricted to aerobic organisms. 



By repeated blood cultures in hypothermic mice, bacteremia was 

 found to be an almost constant result of deep and prolonged hypo- 

 thermia, as shown in the Figures 2 and 3. It should be noted that no 

 bacterial type was ever demonstrated in the blood without having 

 been found previously in the intestine. Intestinal and blood findings 

 were not compared by serological typing but inbiochemical reaction 

 of E, coli atrains and in Dienes' identity test for Proteus bacilli 

 (Dienes, 1946) full conformitywasfoundbetweeneverypair of strains 

 tested. 



As to the route of the bacterial invasion from the intestine. 

 Figures 4 and 5 indicate that in sacrificed or succumbed mice, bac- 

 teria were more often found in peritoneal fluid without being present 

 in the blood than inbloodwithoutbeing found in the peritoneal cavity. 

 Thus, the invasion often started with a peritonitis but seemed also to 

 take place directly into the lymph or blood stream. Hammond et al., 

 (1954) refer to experiments where bacteria were found to penetrate 

 the intestinal wall and to reach the mesenteric lymph nodes in 

 X- irradiated mice, 



A demonstrable occurrence of bacteria in the blood can, apart 

 from an abnormal import as suggested by Dillingham (19 57), be due 

 to a diminished ability of the organism to eliminate bacteria from 

 the blood stream. Our experiments reported in Figure 7 demonstrate 

 such an impaired elimination; the more it was decreased, the longer 



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