What lab values are normal in pernicious anemia?

In the case of pernicious anemia, which is a type of megaloblastic anemia caused by vitamin B12 deficiency, understanding the lab values is crucial. The correct choice highlights that values like mean corpuscular volume (MCV) and mean corpuscular hemoglobin concentration (MCHC) are often normal or can show varying results in different contexts.

Pernicious anemia typically presents with macrocytic red blood cells, which means that the MCV is usually elevated due to the larger size of the red blood cells. However, MCHC can often remain within normal limits or experience slight variations. This means that while MCV can provide a clue indicating the presence of anemia, MCHC may not indicate abnormalities.

The reason the other options are chosen as incorrect relates to the typical presentation of pernicious anemia. For instance, hemoglobin (Hgb) and hematocrit (Hct) can be low due to the anemia but might show normal values early in the disease or in cases of mild deficiency. Similarly, mean corpuscular hemoglobin (MCH) can be affected as well; in macrocytic anemias, it's often lower, contrary to what might be normal. Total iron binding capacity (TIBC) can vary