This calculator will help pinpoint potential causes of anemia based on an automated flowchart approach.  Start by making your first selection below, then press analyze.

Background

Anemia is defined as a decrease in the total amount of red blood cells (RBCs) or hemoglobin in the blood and is present when it falls below certain thresholds depending on the age, gender, and race of the patient.   Based on WHO criteria, the lower limit of normal in adults is 13 g/dL in men and 12 g/dL in women. The blood hemoglobin concentration may more accurately indicate the total red cell mass compared with the hematocrit.  The various types of anemia are due to blood loss (usually gastrointestinal bleeding, trauma, others),  decreased red blood cell production (iron deficiency, a lack of vitamin B12, folic acid, thalassemia, and a number of neoplasms), or increased red blood cell breakdown ( genetic conditions such as sickle cell anemia, infections e.g. malaria, and certain autoimmune diseases).  The type of anemia can also be classified based on the size of the red blood cells and the amount of hemoglobin present in each cell.  Examples  include: microcytic (smaller RBC's), macrocytic (larger), or normocytic (normal RBC size).  Hypochromic (paler than normal - less red).

Symptoms vary greatly and depend on the onset and the individual's ability to compensate for a loss in oxygen-carrying capacity.  Anemia with a slow onset may go undetected or present with vague symptoms including tiredness, weakness, shortness of breath, poor concentration or reduced exercise tolerance.  Anemia that occurs rapidly often has more obvious symptoms such as confusion, mental status changes, lightheadedness, loss of consciousness, palpitations, respiratory distress, or hypotension.  Symptoms are often more severe if there is underlying coronary artery disease, congestive heart failure, or  intrinsic pulmonary or cerebrovascular disease. Typical signs exhibited may include pallor (pale skin, lining mucosa, conjunctiva and nail beds), however, further testing is required to confirm the diagnosis.

References

1. Alldredge BK, Corelli RL, Ernst ME, Guglielmo BJ, eds. Anemias. In: Koda-Kimble & Young's Applied Therapeutics: The Clinical Use of Drugs. 10th ed. Philadelphia, PA: Lippincott Williams & Wilkins;2013;303-307.
   
   
2. Beata I, Mason BJ, and Thompson EG. Anemias. In: DiPiro JT, Talbert RL, Yee GC, et al, eds. Pharmacotherapy: A Pathophysiologic Approach. 6th ed. New York, NY: McGraw-Hill Inc; 2005:1806-1817.
   
   
3. Cook JD. Diagnosis and management of iron-deficiency anaemia. Best Pract Res Clin Haematol 2005;18:319-32.
   
   
4. Guyatt GH, Oxman AD, Ali M, Willan A, McIlroy W, Patterson C. Laboratory diagnosis of iron-deficiency anemia: an overview. J Gen Intern Med. 1992 Mar-Apr;7(2):145-53.
   
   
5. Lopez A, Cacoub P, Macdougall IC, Peyrin-Biroulet L. Iron deficiency anaemia. Lancet. 2016 Feb 27;387(10021):907-16. doi: 10.1016/S0140-6736(15)60865-0. Epub 2015 Aug 24.
   
   
6. Wians FH Jr, Urban JE, Keffer JH, Kroft SH. Discriminating between iron deficiency anemia and anemia of chronic disease using traditional indices of iron status vs transferrin receptor concentration. Am J Clin Pathol. 2001 Jan;115(1):112-8.  [Pubmed]
   
   
7. Zarychanski, R; Houston, DS (Aug 12, 2008). "Anemia of chronic disease: a harmful disorder or an adaptive, beneficial response?". CMAJ : Canadian Medical Association Journal. 179 (4): 333–7. [Pubmed]