By Mary Ellen Posthauer RDN, CD, LD, FAND
One component of the nutritional assessment process in wound care is reviewing and evaluating biochemical data. In a previous blog I discussed the relationship of albumin and pre-albumin (transthyretin) to nutritional status. Many lab values are affected by hydration status and/or medications, which may increase or decrease levels.
The Centers for Medicare (CMS) F tag 314 Guidance for Surveyors in Long Term Care Facilities states: "Although some laboratory tests may help clinicians evaluate nutritional issues in a resident with pressure ulcers, no laboratory test is specific or sensitive enough to warrant serial/repeated testing. Serum albumin, pre-albumin, and cholesterol may be useful to help establish overall prognosis; however, they may not correlate with clinical observation of nutritional status."1
The focus this month is nutritional anemias, which can have a negative effect on wound healing, since blood transports oxygen to the wound bed. Signs and symptoms of anemia include fatigue, pale skin, malaise, and general weakness. There are four types of nutritional anemias:
- Iron Deficiency Anemia
- Megaloblastic Anemia
- Pernicious Anemia
- Anemia of Chronic and Inflammatory Disease
Iron Deficiency Anemia
Iron deficiency anemia may be a result of chronic blood loss, acute blood loss, malabsorption of iron or a deficient diet. The habitual consumption of antacids leads to decreased stomach acidity, which may result in impaired iron absorption leading to iron deficiency anemia. Spooned shaped nails, inflammation of the lips, tongue and mucous membranes of the mouth are clinical signs of this anemia. Laboratory tests to diagnose iron deficiency anemia include low hemoglobin and hematocrit, low mean corpuscular volume (MCV), low serum iron, low ferritin and elevated total iron binding capacity (TIBC). Oral iron therapy given on an empty stomach is the treatment for iron deficiency anemia. Since oral iron can cause gastric upset, side effects diminish and absorption increases if administered with a source of vitamin C, such as orange juice.
Folate deficiency or megaloblastic anemia is frequently observed in older adults and has been associated with an increased risk of end-stage renal disease or heart disease. Megaloblastic anemia is triggered by a malabsorption of folate, and/or vitamin B12 deficiency, deficient diet or an increased need for folate. Low hemoglobin, hematocrit, and blood cell folate plus elevated MCV, serum iron, ferritin and homocysteine are tests to diagnose this anemia. Megaloblastic anemia is treated based on its etiology. Individuals taking folate antagonists, such as anticonvulsants or methotrexate, require prescription strength folate.
Pernicious anemia or vitamin B12 deficiency found commonly in older adults and is also triggered by an inadequate diet (vegans) or malabsorption. Dietary B12 is bound to a protein carrier and once the vitamin is released from its protein carrier in the stomach, it forms an intrinsic factor for absorption. Without the intrinsic factor B12 cannot be absorbed, body stores are exhausted and the body produces immature red blood cells. Atrophic gastritis (decline in gastric acid) causes the decrease in absorption and utilization of B12. Proton pump inhibitors can impede the absorption of vitamin B12 and diseases associated with malabsorption (Crohn’s, Celiac) can cause impaired B12 absorption. Biochemical tests include low hemoglobin, hematocrit, and serum B12; normal or elevated MCV; and serum iron, ferritin, folate, and homocysteine. If the body is unable to absorb B12, monthly injections of B12 or oral, nasal spray or patches are all treatments.
Anemia of Chronic and Inflammatory Disease
Older adults and individuals with diseases such as congestive heart failure, chronic renal failure, AIDS, gastrointestinal reflux disease, and Crohn’s disease are all prone to anemia of chronic or inflammatory disease. Unintended weight loss and hypoalbuminemia are characteristics of this disease. Laboratory values for anemia of chronic disease include low hemoglobin, hematocrit, serum iron, and TIBC however MCV and ferritin are within normal range.
Since anemia is symptomatic of a disease and its prevalence increases with age, laboratory evaluation should be included in the individual’s assessment.
1. Department of Health and Human Services. CMS Manual System. State Operations: Provider Certification. Center for Medicare & Medicaid Services (CMS) Guidance to Surveyors for Long-Term Care Facilities. Transmittal 4. November 12, 2004. DHHS Pub. 100-07.
About The Author
Mary Ellen Posthauer RDN, CD, LD, FAND is an award winning dietitian, consultant for MEP Healthcare Dietary Services, published author, and member of the Purdue University Hall of Fame, Department of Foods and Nutrition, having held positions on numerous boards and panels including the National Pressure Ulcer Panel and the American Dietetic Association’s Unintentional Weight Loss work group.
The views and opinions expressed in this blog are solely those of the author, and do not represent the views of WoundSource, Kestrel Health Information, Inc., its affiliates, or subsidiary companies.