My grandfather, 91 years old, for past week bruised easily. This senile purpura is likely due to capillary fragility. But today, he passed out fresh blood. What could be the likely cause?
I'm assuming that your grandfather passed fresh blood from his rectum? If he has been bruising easily he could have a bleeding hemmoroid or a lower intestinal bleed. If the rectal bleeding continues he should be seen by a doctor. A nuclear medicine scan would show if he has a GI bleed.