Low lymphocyte count worrisome

Dear Dr. Roach: I am a 58-year-old male. Several months ago, I lost 17 pounds, and even though I have gained back about 2 pounds in the past month, I cannot gain the weight back, even by increasing my food intake. I feel tired all the time, and my energy level is not good. My doctor did a CBC, and my white blood cell count is low, at 3.1 (range is 4-11). He asked me if I recently had a cold, and I told him I had not. Because it was a new doctor, there are no previous results for comparison. The doctor did not tell me anything or instruct me to do anything else, which concerns me. There are two other results with low readings: lymphocytes are 0.1 (range is 1.2-3.4), and lymphocyte percent is 3.4 (range is 20-45). I would like to know what, if anything, I should do next, other than waiting a few months for another blood test. Do I have to be worried about this? – V.B. Answer: I am sorry, but you do have to be worried about this. Your lymphocyte count is extremely low. There are many potential causes, some of which are serious. Infections are the most common cause. Any serious infection can temporarily reduce lymphocyte count, but most of these are acute, to the point that people need hospitalization. One common infection to cause a low lymphocyte count is HIV. In the early days of the epidemic, a low lymphocyte count was a clue to either acute or advanced HIV. The Centers for Disease Control and Prevention recommends, and I agree, that all adults should get an HIV test as a part of their routine checkups, and that people with ongoing risk should get a test annually. A partial list of other causes for low lymphocyte count include medications (usually powerful anti-immune-system medicines or chemotherapy), autoimmune diseases such as lupus or rheumatoid arthritis, lymphoma and other cancers, and primary diseases of the immune system, such as aplastic anemia. Previous results would help indicate whether this is a new condition. This can’t wait a few months for a follow-up test. If your doctor isn’t looking aggressively for the cause, you need a second opinion. Dear Dr. Roach: While reading your recent article about sulfites, a question came to mind: What are sulfites? Are they mineral, chemical, organic? Do they grow on trees? How do they affect food? – M.C. Answer: Sulfites are chemicals found naturally at low levels in wine and some foods, and are used as preservatives at significantly higher levels. Most people are not sensitive to sulfites even at high levels, but some people have significant reactions even at fairly low levels. People with severe allergies need to know sulfites are not always indicated on the label and should educate themselves about all the foods containing sulfites. One resource I found is at edis.ifas.ufl.edu/fy731.