The diagnosis of a patient with anemia can be based on the red blood cell indices and reticulocyte count.
Initial data:
(1) based on red blood cell indices (MCV, MCH, MCHC), is the patient?
(a) hypochromic, microcytic
(b) normochromic, normocytic
(c) macrocytic
(2) Is there evidence of reticulocytosis?
|
Indices |
Reticulocytosis |
Other Findings |
Consider |
|
hypochromic, microcytic |
yes |
|
hemoglobinopathy |
|
hypochromic, microcytic |
no |
decreased iron stores |
iron deficiency |
|
hypochromic, microcytic |
no |
iron stores not decreased |
anemia of chronic disease |
|
hypochromic, microcytic |
no |
iron stores not decreased |
bone marrow production failure |
|
normochromic, normocytic |
yes |
|
acute blood loss |
|
normochromic, normocytic |
yes |
|
hemolytic anemia |
|
normochromic, normocytic |
no |
|
anemia of chronic disease |
|
normochromic, normocytic |
no |
|
bone marrow production failure |
|
macrocytic |
yes |
|
prior hemorrhage |
|
macrocytic |
yes |
|
treated vitamin B12 or folate deficiency |
|
macrocytic |
no |
decreased levels of vitamin B12 and/or folate |
vitamin B12 and/or folate deficiency |
|
macrocytic |
no |
|
antimetabolite drugs |
where:
• Evaluation of reticulocytosis should assess whether the degree of the reticulocyte response is appropriate to the degree of anemia. Mild marrow hypoproduction may be masked if other causes of anemia are also present. The evaluation may be based on the reticulocyte production index or other reticulocyte index.
• Assessment of vitamin B12 status should include measurement of methylmalonic acid (MMA) in addition to serum vitamin B12.
Limitations:
• The flow diagram assumes that the anemia is due to a single cause. A person with anemia from multiple etiologies may need to be re-evaluated after each cause is identified and treated, based on the residual features. For example, mixed iron deficiency and beta-thalassemia often requires demonstration of microcytosis after repletion of the depleted iron stores.
Specialty: Hematology Oncology, Clinical Laboratory
