Hi:

 

I've heard that most types shock of any can cause diarrhea because the autonomic nervous system responds to the hypoperfusion by constricting blood vessels that supply the colon. This starvation of oxygen irritates the colon, leading to diarrhea. However, in septic shock, all blood vessels around the body dilate due to chemicals released as a result of the infection. So how does septic shock cause diarrhea, if intestinal circulation isn't impaired?

 

 

Thanks,

 

GX

Perhaps septic shock and diarrhea are symptoms of an infection.

Generally diarrhea is caused when water is not well absorbed from the GI. In the case you put forward the mechanism by which that happens is due to vaso-constriction, however perhaps in septic shock this same result is caused by another mechanism?

 

Also, mass vasodilation would cause hypotension and still lead to decreased oxygen availability.

I found this:

 

E. coli Pathogenesis

 

Endotoxin in wall causes septic shock.

 

Two enterotoxins produced. Heat labile toxin (LT) stimulates adenyl cyclate by ADP-ribosylation. Increased cAMP causes outflow of Cl^– and water, resulting in diarrhea.

Edited June 1, 201213 yr by ewmon

Diarrhoea and Septic Shock occuring together shows that the diarrhoea is of an infective origin. Same mechanism responsible for the shock 'll be responsible for the diarrhoea

The only thing I can think of is if the increased capillary permeability associated with septic shock allowed fluid from the intravascular space to be released back into the GI system. It can happen in capillary leak syndrome, so in cases where the osmotic gradient suffers a serious enough derangement, then you could probably get diarrhea secondary to fluid leakage bag into the intestines. But more likely, the pathogen causing the septic shock is causing the diarrhea, rather than the septic shock itself.

Disturbance of normal gut flora could have a role too, like the quote about excessive E. Coli formation. A good example is of the effect Vibrio cholerae has on the gut.

Hello ,

 

Bacterial overgrowth and bacterial invasion to the surrounding blood stream contributes to the pathogenesis of sepsis .

 

Such as in bowel perforation and gram negative bacteria plus anaerobes shifted from the GI to the circulatory system .

 

Moreover , septic shock has two stages warm and cold , when it's cold it means that the cardiovascular system is no longer capable of compensating , therefore bowel ischemia may occur . DIC picture causes bowel ischemia as well .