Final answer:
Gastrointestinal bleeding manifestations include hematemesis indicating upper GI hemorrhage, melena for upper or lower GI hemorrhage, occult bleeding which can be from any part of the GI tract, and hematochezia signaling lower GI hemorrhage. Petechiae and constipation are not direct indicators of gastrointestinal hemorrhage.
Step-by-step explanation:
Gastrointestinal bleeding can manifest in various forms, each indicating different potential locations and causes of hemorrhage in the gastrointestinal tract. Hematemesis is the vomiting of blood, suggesting an acute upper gastrointestinal hemorrhage, possibly due to ulcers or gastritis. Melena, which is characterized by black, tarry stools, can be a sign of upper or lower gastrointestinal hemorrhage. Occult bleeding refers to blood in the feces that is not visible to the normal eye but can be detected through fecal occult blood tests; it may indicate upper or lower gastrointestinal hemorrhage. Hematochezia is the passage of fresh blood through the anus, typically in or with stools, and indicates lower gastrointestinal hemorrhage. It's important to note that constipation is not a direct indicator of gastrointestinal hemorrhage, whereas petechiae are small red or purple spots caused by bleeding into the skin, not typically associated with gastrointestinal bleeding.