Good morning sir, my uncle aged 73 yrs  is admitted since last 3 days in a multispeciality hsptl.He is admitted with 5.1  gms% HB, on day one 2 PCV given.on day 2 one unit of PCV was given , then his HB level went up to 8.5 gms% .on day 3 morning before 4 the unit of PCV his HB level was checked it shows 7.2 gms% , then the 4th unit is ongoing.now he was operated for prostate 10 yrs ago.he has no other problem .even his stool and urine reports are absolutely normal.occult blood is absent in last 2 days stool samples.i want to know ,what are the reasons of such blood lose??? Kindly guide me now what can I do for my uncle??? Thank you so much sir Waiting for your reply Have a great day