What condition is characterized by an MCV greater than 100?

A condition characterized by a mean corpuscular volume (MCV) greater than 100 is known as megaloblastic anemia. This type of anemia typically results from deficiencies in vitamin B12 or folate, leading to the production of abnormally large red blood cells (macrocytes). The enlarged size of these cells is reflected in the increased MCV value.

Megaloblastic anemia is often associated with impaired DNA synthesis, which affects the maturation of red blood cells and causes them to be larger than normal. This condition can be detected through a complete blood count (CBC), where an elevated MCV is one of the key indicators. The condition may also present with symptoms like fatigue, weakness, and pallor, along with potential neurological symptoms if vitamin B12 deficiency is involved.

In contrast, other types of anemia listed, such as microcytic anemia, normocytic anemia, and hemolytic anemia, do not typically present with such an elevated MCV or are associated with different underlying causes or mechanisms.