A client with suspected vitamin B12 deficiency anemia has the following laboratory results: macrocytic (large), hypochromic (pale) RBCs with low hemoglobin (Hgb) and hematocrit (Hct) levels.
The mean corpuscular volume (MCV) is above 100 fL.
Which of the following laboratory tests would further confirm the diagnosis of vitamin B12 deficiency anemia?

Choice A rationale:

Oral supplements are less effective in raising vitamin B12 levels.

Rationale: Vitamin B12 deficiency anemia often results from malabsorption issues in the gastrointestinal tract, where the body cannot adequately absorb vitamin B12 from the digestive system.

In such cases, oral supplements may not be effective because they rely on the digestive system for absorption.

In contrast, vitamin B12 injections bypass the gastrointestinal tract, delivering the vitamin directly into the bloodstream, ensuring absorption, and increasing the effectiveness of treatment.

Choice B rationale:

Injections are less painful for the client.

Rationale: While the pain associated with injections can vary from person to person, it is not the primary reason for choosing injections over oral supplements in the treatment of vitamin B12 deficiency anemia.

The primary consideration is the effectiveness of absorption, as discussed in Choice A's rationale.

Choice C rationale:

Injections have fewer side effects.

Rationale: Both oral supplements and vitamin B12 injections have their own set of potential side effects, but the choice between the two primarily depends on the underlying cause of the deficiency and the ability to absorb vitamin B12.

Therefore, the assertion that injections have fewer side effects is not the primary reason for choosing them.

Choice D rationale:

Oral supplements may cause gastrointestinal distress.

Rationale: This is the correct answer.

Oral supplements of vitamin B12 may cause gastrointestinal distress, particularly in individuals with gastrointestinal issues.

These supplements can be hard for some individuals to tolerate, leading to discomfort, gas, or other gastrointestinal symptoms.

This is a significant consideration when choosing the route of administration for vitamin B12 treatment.

Choice A rationale:

Pale skin (pallor) is a common symptom of anemia, but it is not specific to vitamin B12 deficiency anemia.

Many types of anemia can lead to paler skin.

Choice B rationale:

Joint pain and stiffness are not typically associated with vitamin B12 deficiency anemia.

This symptom is more characteristic of other conditions, such as arthritis.

Choice C rationale:

This is the correct answer.

Feeling lightheaded and dizzy when standing up quickly is a common symptom of anemia, including vitamin B12 deficiency anemia.

Anemia can lead to decreased oxygen delivery to the brain, resulting in dizziness upon sudden position changes.

Choice D rationale:

Higher energy levels are not a typical symptom of vitamin B12 deficiency anemia.

Fatigue and weakness are more common symptoms of this condition.