NS235 Unit 5 Deficiency Case Study Example

Twenty Donations in Four Years: A Unit 5 Deficiency Case Study Building the Argument for Iron Depletion in a Frequent Blood Donor

[Student Name]

Purdue University Global

NS235: Micronutrient Metabolism

Unit 5 Deficiency Case Study

[Instructor Name]

[Date]

The donor, his history and his laboratory values are composite; the blood donor studies, the iron review and the reference report cited are real.

The Case

Ray, a composite 47-year-old high school chemistry teacher, has donated whole blood about every eight weeks for four years, twenty-one donations in all. He is proud of his donor record. Over the past six months he has felt more tired than usual, has noticed shortness of breath on the stairs at school and has developed restless legs at night. At his most recent donation, his fingerstick hemoglobin was 13.1 grams per deciliter, just above the 13.0 cutoff for male donors, and he was allowed to donate. His physician later ordered blood tests.

He eats a mixed diet including red meat twice a week, takes no supplements and has no symptoms of blood loss from the gut.

Why Donors Lose Iron

Each whole blood donation removes about 500 milliliters of blood, containing roughly 200 to 250 milligrams of iron. An adult man absorbs about 1 milligram of iron a day from food to replace normal losses, and absorption can increase when stores are low, but replacing 200 or more milligrams every eight weeks requires a substantial increase. Frequent donors are therefore at risk of depleting their stores (Cable et al., 2012).

The Stages of Iron Deficiency

Iron deficiency develops in stages. First, iron stores, mostly ferritin in the liver, bone marrow and spleen, are depleted. Second, iron supply to developing red blood cells becomes limited, shown by falling transferrin saturation. Third, hemoglobin falls and anemia appears (Camaschella, 2015). Hemoglobin is the last marker to change, which is why a donor can pass the hemoglobin screen while his stores are empty.

Ray's Laboratory Results

1. Hemoglobin: 13.2 grams per deciliter, within the normal range for men.

2. Mean corpuscular volume: 82 femtoliters, at the low end of normal.

3. Serum ferritin: 9 nanograms per milliliter, below the commonly used cutoff of 15 and well below 30, which many clinicians use as a sign of depleted stores.

4. Transferrin saturation: 12 percent, below the usual threshold of about 16 to 20 percent.

Building the Argument

Stage 1, depleted stores. Ferritin reflects iron stores in people without inflammation. A value of 9 indicates that Ray's stores are essentially empty. Ferritin can be raised falsely by inflammation, but Ray has no signs of infection or inflammatory illness, so a low value is reliable evidence of depletion.

Stage 2, limited supply. Transferrin saturation of 12 percent shows that too little iron is circulating to supply the bone marrow fully. Together with a mean corpuscular volume at the low end of normal, this suggests red blood cell production is beginning to be affected.

Stage 3, anemia. Ray's hemoglobin is still normal, so he does not yet have iron-deficiency anemia. He has iron deficiency without anemia.

Ray passed every hemoglobin screen at the donation center because hemoglobin is the last thing to fall; his ferritin and transferrin saturation show that his stores emptied long before his blood count could reveal it.

Why Hepcidin Matters

Hepcidin, a liver-derived peptide, sets the pace of iron entry. High stores push its level up, and it then holds iron inside gut and storage cells. When stores fall, hepcidin falls and absorption increases (Camaschella, 2015). In Ray's case, low hepcidin would be expected to increase absorption of the iron in his diet, which is the body's response to his donations. But the increase has limits, and absorbing an extra 2 to 4 milligrams a day, which repeated donation would require, is more than most diets can supply. Hepcidin also rises with inflammation and with hard exercise, which can reduce absorption at times when iron is needed, a point relevant to donors who are also endurance athletes.

Do His Symptoms Fit?

Fatigue, reduced exercise tolerance and restless legs have all been associated with iron deficiency, including without anemia. Restless legs in particular are linked to low brain iron. His symptoms are consistent with the laboratory picture, though they are not specific, and his physician would consider other causes.

The Evidence From Donor Studies

A large study of blood donors in the United States found iron deficiency common among frequent donors: among returning frequent male donors, nearly half showed iron-deficient red cell production and about a fifth had absent iron stores. Shorter intervals between donations and more donations in the past two years predicted depletion, and taking iron supplements reduced the risk (Cable et al., 2012). A randomized trial found that donors given oral iron after donation recovered hemoglobin much faster than those not given iron, particularly when their ferritin was low (Kiss et al., 2015).

Why Diet Alone Was Not Enough

Ray's diet contains heme iron from red meat twice a week, which is well absorbed, and nonheme iron from grains and vegetables. His estimated intake of about 14 milligrams a day exceeds the Recommended Dietary Allowance of 8 milligrams for adult men (Institute of Medicine, 2001). But the allowance is set to replace normal losses, not repeated donation losses. Even with good absorption, his diet could not keep pace with eight-week donations.

What Other Explanations Were Considered

A careful argument considers alternatives. Blood loss from the gut, such as from an ulcer or a colon polyp, can cause iron deficiency in men and must be ruled out, especially at Ray's age. Celiac disease can impair iron absorption. Heavy use of anti-inflammatory drugs can cause slow bleeding. Ray's physician would consider these before attributing the deficiency to donation alone. The donation history makes donation the most likely cause, but likelihood is not proof, and the decision to investigate further belongs to the physician.

Implications

Ray's physician is the one to decide on treatment, which for iron deficiency usually means oral iron supplementation and investigation to rule out other sources of blood loss. The donor studies suggest that Ray should lengthen the interval between donations or take iron supplements if he continues to donate, decisions he should make with his physician and the blood center. Many blood centers now measure ferritin in frequent donors or recommend iron supplements for them.

What This Case Shows About Deficiency

The case illustrates the general principle of staged deficiency. Laboratory markers change in sequence: stores first, transport next, function last. A single marker read alone, such as hemoglobin, can miss early deficiency. Building the argument stage by stage, with each marker interpreted in context, gives a clearer picture than any single number.

References

Cable, R. G., Glynn, S. A., Kiss, J. E., Mast, A. E., Steele, W. R., Murphy, E. L., Wright, D. J., Sacher, R. A., Gottschall, J. L., Tobler, L. H., & Simon, T. L. (2012). Iron deficiency in blood donors: The REDS-II Donor Iron Status Evaluation (RISE) study. Transfusion, 52(4), 702-711. https://doi.org/10.1111/j.1537-2995.2011.03401.x

Camaschella, C. (2015). Iron-deficiency anemia. New England Journal of Medicine, 372(19), 1832-1843. https://doi.org/10.1056/NEJMra1401038

Institute of Medicine. (2001). Dietary reference intakes for vitamin A, vitamin K, arsenic, boron, chromium, copper, iodine, iron, manganese, molybdenum, nickel, silicon, vanadium, and zinc. National Academies Press. https://doi.org/10.17226/10026

Kiss, J. E., Brambilla, D., Glynn, S. A., Mast, A. E., Spencer, B. R., Stone, M., Kleinman, S. H., & Cable, R. G. (2015). Oral iron supplementation after blood donation: A randomized clinical trial. JAMA, 313(6), 575-583. https://doi.org/10.1001/jama.2015.119