After the repeated passage of black, tarry, and foul-smelling stools, Catherine Baldwin was diagnosed as having ___. This condition is caused by the presence of digested blood in the stools.

Hematochezia

Explanation:

Hematochezia is a condition that occurs due to the partial digestion of RBC's. If the amount of blood in person stool is too much than a EGD test is advised immediately.

Melena

Explanation:

Melena are dark or black stools with foul smelling. This dark stool are either with visible blood or without visible blood and they often occured due to upper gastrointestinal bleeding.

Melena are sometimes caused by peptic ulcer or any bleeding within the lower or upper gastrointestinal.

Some medication like iron supplements or warfarin can also caused dark stool.

This dark stool are often hard to flush down the toilet due to the presence of blood.

Treatment of Melena may include placement of bands around where the bleeding flows from to help stop it and in a case where the person lost much blood blood transfusion may be needed.

Therefore Catherine Baldwin was diagnosed as having MELENA because the condition is caused by the presence of digested blood her the stools.

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