The only problem with using Alt in that spot (X in Linux) is there are a lot of individual items in that section of the room, which can obscure the tooltip for the blood, at least until you've done a fair bit of looting. Actually, it wouldn't be hard to pick up the blood without realizing it, though I think the character should make a comment when doing so (similar to picking up the teleporter pyramids, etc).
In the controller UI, Right Stick Press will toggle showing world tooltips on or off, or holding the A button down will perform a search of the area around the lead character, and bring up a list of items, containers and interactable objects.