Pagana: Mosby’s Manual of Diagnostic and Laboratory Tests, 6th Edition
Iron-Deficiency Anemia
Case Study
A 72-year-old man developed chest pain whenever he was physically active. The pain ceased on
stopping his activity. He has no history of heart or lung disease. His physical examination was
normal except for notable pallor.
Studies Result
Electrocardiogram (EKG), p. 485 Ischemia noted in anterior leads
Chest x-ray study, p. 956 No active disease
Complete blood count (CBC), p.
156
Red blood cell (RBC) count, p.
396
2.1 million/mm (normal: 4.7–6.1 million/mm)
RBC indices, p. 399
Mean corpuscular volume
(MCV)
72 mm3
(normal: 80–95 mm3
)
Mean corpuscular hemoglobin
(MCH)
22 pg (normal: 27–31 pg)
Mean corpuscular hemoglobin
concentration (MCHC)
21 pg (normal: 27–31 pg)
Red blood cell distribution width
(RDW)
9% (normal: 11%–14.5%)
Hemoglobin (Hgb), p. 251 5.4 g/dL (normal: 14–18 g/dL)
Hematocrit (Hct), p. 248 18% (normal: 42%–52%)
White blood cell (WBC) count, p.
466
7800/mm3
(normal: 4,500–10,000/mcL)
WBC differential count, p. 466 Normal differential
Platelet count (thrombocyte
count), p. 362
Within normal limits (WNL) (normal: 150,000–
400,000/mm3
)
Half-life of RBC 26–30 days (normal)
Liver/spleen ratio, p. 750 1:1 (normal)
Spleen/pericardium ratio <2:1 (normal)
Reticulocyte count, p. 407 3.0% (normal: 0.5%–2.0%)
Haptoglobin, p. 245 122 mg/dL (normal: 100–150 mg/dL)
Blood typing, p. 114 O+
Iron level studies, p. 287
Iron 42 (normal: 65–175 mcg/dL)
Total iron-binding capacity
(TIBC)
500 (normal: 250–420 mcg/dL)
Transferrin (siderophilin) 200 mg/dL (normal: 215–365 mg/dL)
Transferrin saturation 15% (normal: 20%–50%)
Case Studies
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Ferritin, p. 211 8 ng/mL (normal: 12–300 ng/mL)
Vitamin B12, p. 460 140 pg/mL (normal: 100–700 pg/mL)
Folic acid, p. 218 12 mg/mL (normal: 5–20 mg/mL or 14–34 mmol/L)
Diagnostic Analysis
The patient was found to be significantly anemic. His angina was related to his anemia. His
normal RBC survival studies and normal haptoglobin eliminated the possibility of hemolysis..
His RBCs were small and hypochromic. His iron studies were compatible with iron deficiency.
His marrow was inadequate for the degree of anemia because his iron level was reduced.
On transfusion of O-positive blood, his angina disappeared. While receiving his third unit of
packed RBCs, he developed an elevated temperature to 38.5°C, muscle aches, and back pain.
The transfusion was stopped, and the following studies were performed:
Studies Results
Hgb, p. 251 7.6 g/dL
Hct, p. 248 24%
Direct Coombs test, p. 157 Positive; agglutination (normal: negative)
Platelet count, p. 362 85,000/mm3
Platelet antibody, p. 360 Positive (normal: negative)
Haptoglobin, p. 245 78 mg/dL
Diagnostic Analysis
The patient was experiencing a blood transfusion incompatibility reaction. His direct Coombs
test and haptoglobin studies indicated some hemolysis because of the reaction. His platelet count
dropped because of antiplatelet antibodies, probably the same ABO antibodies that caused the
RBC reaction.
He was given iron orally over the next 3 weeks, and his Hgb level improved. A rectal
examination indicated that his stool was positive for occult blood. Colonoscopy indicated a rightside colon cancer, which was removed 4 weeks after his initial presentation. He tolerated the
surgery well.
Critical Thinking Questions
1. What was the cause of this patient’s iron-deficiency anemia?
2. Explain the relationship between anemia and angina.
3. Would your recommend B12 and Folic Acid to this patient? Explain your rationale for
the answer
4. What other questions would you ask to this patient and what would be your rationale for
them?
- The cause of this patient’s iron-deficiency anemia can be attributed to chronic occult gastrointestinal bleeding, likely from the right-side colon cancer discovered later in the diagnostic process. The low hemoglobin (Hgb) and hematocrit (Hct) levels, along with the reduced iron levels, elevated total iron-binding capacity (TIBC), and low ferritin levels, are consistent with iron deficiency anemia. The positive fecal occult blood test and subsequent colonoscopy confirmed the presence of gastrointestinal bleeding, which was the underlying cause of his anemia.
- The relationship between anemia and angina is primarily related to the decreased oxygen-carrying capacity of the blood. Anemia results in a reduced number of red blood cells, which are responsible for transporting oxygen to the body’s tissues and organs. When there are fewer red blood cells, less oxygen is delivered to the heart muscle, which can lead to myocardial ischemia or inadequate oxygen supply to the heart. This can manifest as chest pain or angina, especially during physical activity when the heart requires more oxygen. In this case, the patient’s chest pain during physical activity was a result of his anemia, as indicated by the improvement in his angina symptoms after receiving a blood transfusion.
- It would be reasonable to consider vitamin B12 and folic acid supplementation for this patient, especially if further testing confirms deficiencies. However, based on the provided lab results, the patient’s vitamin B12 and folic acid levels are within the lower end of the normal range, but they are not severely deficient. The normal ranges for vitamin B12 and folic acid are 100-700 pg/mL and 5-20 mg/mL (or 14-34 mmol/L), respectively, and the patient’s values are 140 pg/mL and 12 mg/mL, respectively. While not severely deficient, these levels are at the lower end of the normal range.
Given the patient’s advanced age and the presence of gastrointestinal bleeding from colon cancer, it would be prudent to monitor his vitamin B12 and folic acid levels over time and supplement if there is any evidence of further decline or deficiency. Additionally, addressing the underlying cause of his anemia by treating the colon cancer will also help improve his overall nutritional status.
- Additional questions to ask the patient and their rationale could include:
a. Have you experienced any changes in bowel habits, such as blood in the stool, constipation, or diarrhea? This question aims to gather more information about gastrointestinal symptoms and potential signs of colorectal pathology.
b. Do you have a family history of anemia or gastrointestinal disorders? Family history can provide valuable insights into the patient’s risk factors for certain conditions.
c. Have you noticed any unintentional weight loss or changes in appetite? Unexplained weight loss can be indicative of various underlying medical conditions, including cancer.
d. Do you have any other medical conditions or take any medications regularly? This information can help identify potential factors contributing to the patient’s anemia or other health issues.
e. Have you had any recent surgeries or procedures other than the colonoscopy? Knowledge of recent medical interventions can aid in understanding the patient’s medical history.
f. Do you experience any other symptoms, such as fatigue, weakness, shortness of breath, or dizziness? These symptoms can be associated with anemia and provide further context for the patient’s overall health.
g. Are there any dietary restrictions or changes in your diet that you have made recently? Understanding dietary habits can help assess nutritional factors contributing to the patient’s condition.
h. Have you ever had any allergic reactions or transfusion reactions in the past? This information is relevant due to the patient’s adverse reaction to the blood transfusion in this case.
i. Are there any other concerning symptoms or changes in your health that you have noticed? This open-ended question allows the patient to share any additional information that may be relevant to their medical history.
j. Are you currently taking any iron supplements or any other over-the-counter medications or supplements? This question helps ascertain whether the patient is already receiving iron supplementation or taking any substances that may impact their iron levels.