DEAR DR. ROACH: I'm a 73-year-old male. My recent bloodwork showed a mild anemia. My doctor ordered a second blood test and a cancer screening kit. The anemia was stable, and the screening was normal with no microscopic blood detected. He is not sure why my bloodwork showed a mild anemia and has me scheduled to repeat testing every three months. He has requested that I monitor my stools for evidence of bloody or black diarrhea. There has been no evidence of such as of yet. I had a colonoscopy a little over three years ago that resulted in one polyp being removed, and I had mild inflammation in my colon that was attributed to the solution used to clean out the colon.
Is there any possible explanation for the mild anemia other than looking for evidence of blood in my stools? — C.W.
ANSWER: In general, there are two major categories of anemia: your body is not making enough, or you're losing blood.
If you're not making enough blood, it can be because of a lack of the nutrients needed to do so. Folic acid, vitamin B-12 and iron are the most common nutrients to cause this. Your doctor normally would check this once the anemia is confirmed. If it's the case, treatment is both replacing the nutrient and figuring out why you didn't have enough to begin with.
Diseases of the bone marrow, of which there are many, is the other major class of underproduction anemias. At age 73, your doctor should be considering that possibility, which often requires a visit to a hematologist and a biopsy of the bone marrow to sort out for certain.
Losing blood is sometimes obvious, but when it isn't, the gastrointestinal tract is, by far, the leading place it is lost. Colon cancer is the first concern, but that is unlikely (but not impossible) only three years out from a normal colonoscopy.
I suspect you may be iron deficient, which is why your doctor is so concerned about loss from your gut.
Dr. Roach regrets that he is unable to answer individual letters, but will incorporate them in the column whenever possible. Readers may email questions to ToYourGoodHealth@med.cornell.edu or send mail to 628 Virginia Dr., Orlando, FL 32803.