From the Guidelines
Low MCV (mean corpuscular volume) is primarily caused by iron deficiency anemia, which is the most common cause worldwide, and can also be caused by thalassemia, lead poisoning, anemia of chronic disease, and sideroblastic anemia. The causes of low MCV can be categorized into several groups, including:
- Iron deficiency anemia, which occurs due to inadequate dietary intake, poor absorption, or blood loss, particularly from gastrointestinal bleeding or heavy menstrual periods 1
- Thalassemia, a genetic disorder affecting hemoglobin production, which is another significant cause of low MCV 1
- Lead poisoning, which can interfere with heme synthesis, resulting in microcytic anemia 1
- Anemia of chronic disease, associated with conditions like rheumatoid arthritis, cancer, or kidney disease, which may also present with low MCV 1
- Sideroblastic anemia, where the body cannot properly use iron to make hemoglobin, which can cause microcytosis 1
- Certain medications like isoniazid or chloramphenicol, which may induce low MCV as a side effect 1
Diagnosis of low MCV typically involves:
- Complete blood count (CBC) to determine the MCV and other blood cell parameters 1
- Iron studies, including serum ferritin and transferrin saturation, to assess iron deficiency 1
- Sometimes genetic testing for thalassemia or other genetic disorders 1
Treatment of low MCV depends on the underlying cause, ranging from:
- Iron supplementation for iron deficiency anemia 1
- Specific management for genetic disorders, such as thalassemia 1
- Addressing chronic conditions, such as anemia of chronic disease 1
From the Research
Causes of Low MCV
The causes of low Mean Corpuscular Volume (MCV) can be attributed to various factors, including:
- Iron deficiency anemia, which is the most common cause of microcytic anemia 2, 3
- Thalassemia, a genetic disorder that affects the production of hemoglobin 2, 3
- Anemia of chronic disease, which can be caused by chronic inflammation or infection 2, 4
- Sideroblastic anemia, a rare disorder that affects the production of red blood cells 3
- Sickle cell anemia, a genetic disorder that affects the shape of red blood cells 3
Acquired and Congenital Causes
The causes of microcytic anemia can be classified into acquired and congenital causes, which should be considered separately according to the age of the patient, risk factors, and coexisting signs and symptoms 3.
- Acquired causes include iron deficiency anemia, anemia of chronic disease, and sideroblastic anemia
- Congenital causes include thalassemia, sickle cell anemia, and other genetic disorders
Diagnostic Features
Certain diagnostic features can help differentiate between different causes of microcytic anemia, including: