In pernicious anemia, which lab values tend to be decreased?

In pernicious anemia, the primary issue is a deficiency in vitamin B12, which is essential for producing healthy red blood cells. This deficiency leads to characteristic laboratory findings.

The correct answer highlights the lab values of hemoglobin (Hgb) and hematocrit (Hct), which are typically decreased in pernicious anemia as a result of the body producing fewer and larger red blood cells due to impaired DNA synthesis. Additionally, serum vitamin B12 levels are decreased because the condition is specifically related to the body's inability to absorb this nutrient properly due to a lack of intrinsic factor, which is necessary for vitamin B12 absorption in the intestine.

Understanding these changes in lab values is crucial because they reflect the underlying pathophysiology of pernicious anemia, where the deficiency in vitamin B12 directly impacts red blood cell production, leading to anemia. Recognizing these specific lab values can help in diagnosing this type of anemia and differentiating it from other anemias, such as those caused by iron deficiency or chronic disease.

Other options mention different values that are not typically decreased in the context of pernicious anemia, making them less relevant when considering the direct implications of this condition.