What’s Causing My Anemia? Understanding Low Hemoglobin and High Reticulocyte Counts

Question: My recent complete blood count had a hemoglobin level of 7.1 g/dL and a reticulocyte count of 5%. My doctor is concerned about anemia, possibly due to chronic disease, but could conditions like hemolytic anemia or a bone marrow disorder also explain these findings? What follow-up tests are recommended to narrow down the cause?

Dr. Shannon Kern: Anemia is when your hemoglobin (Hb) is below the lowest reference range interval. In men this is usually around 13 g/dl and in women 12 g/dl. A hemoglobin of 7.1 g/dl is very low, and follow-up studies should be conducted. The first thing to look at with a low hemoglobin is the mean corpuscular volume (MCV), or the size of the red blood cells. This will give direction as to the underlying cause of the anemia and is part of a normal complete blood count (CBC).

That means if you have a printout of your test results, you should be able to see the MCV result. If the MCV is less than 80 fl, iron studies would be the next logical step. These would include ferritin, total iron binding capacity, and iron. Often clinicians will order some iron studies when they order the CBC so the patient only has to have blood drawn once, especially if they suspect anemia.

It is possible these tests are in your results. If the MCV is within the range of 80-100 fl, it would need to be correlated to the reticulocyte count. Reticulocytes are red blood cells that are not yet mature but have been released by the bone marrow to help the body handle the anemia. The reference range for the reticulocytes should be on your lab results, but 5% is considered elevated. Anemia of chronic diseases usually presents with a low reticulocyte count, and your reticulocyte count is elevated.

Not having any other information, a low hemoglobin and an elevated reticulocyte count need to have further evaluation. Because you specifically mentioned it, yes-hemolytic anemia could be an explanation to these findings. Hemolytic anemia can be caused by inherited conditions, medications, or infections. Further tests that should be considered include iron studies, lactate dehydrogenase (LDH), and bilirubin. The clinician should also order a manual differential on the CBC so the laboratorians can provide the size and shape of the red blood cells which are good indicators of any underlying conditions.

Answered by Shannon Kern, Pro Hub Expert on Apr 27, 2025 12:46

Additional Resources

American Society of Hematology (ASH): https://www.hematology.org/education/patients/anemia