Symptom Finder - Anemia
ANEMIA
In developing a list of diagnostic possibilities in cases of anemia, physiology is the key. Anemia may be caused by a decrease in red cell production, a break in the transport system (blood loss), or excessive red cell destruction.
Decreased production: This should bring to mind iron deficiency anemia, folate deficiency, and pernicious anemia. Production also is decreased when the bone marrow is infiltrated with leukemia or metastatic neoplasms. Replacement of the marrow by fibrous tissue (as occurs in myelofibrosis) also decreases production. Cirrhosis of the liver may be associated with anemia due to lack of ability to store B12, folic acid, and
iron, thus reducing production. Decreased production should also bring to mind aplastic anemia, toxic or idiopathic.
Break in the transport system (blood loss): Trauma to any part of the body may cause significant blood loss. Massive hematemesis associated with esophageal varices or gastric ulcers is also obvious. However, chronic GI blood loss from bleeding ulcers, neoplasms, and diverticulitis is not.
Also, insidious is the anemia associated with excessive menses or metrorrhagia. This can be dysfunctional or associated with fibroids or endometrial carcinoma and other tumors.
Increased destruction: This should prompt recall of the haemolytic anemias—hereditary or acquired. Sickle cell anemia, thalassemia (major and minor), and hereditary spherocytosis are the major genetic anemias.
Acquired hemolytic anemias include hemolytic anemias associated with lymphoma, leukemia, collagen disease, and idiopathic type. Hemolytic anemia may also be associated with infectious diseases such as malaria, Oroya fever, babesiosis, and septicemia. The hemolytic anemia associated with transfusion should not pose a diagnostic dilemma. Finally, toxins and drugs such as phenacetin, primaquine, and lead may induce a haemolytic anemia.
Miscellaneous conditions: A large spleen from whatever cause may induce anemia based on both excessive red cell destruction and decreased red cell production. Hypothyroidism is also associated with an anemia that may be due to multiple causes. Simple chronic anemia associated with chronic inflammatory conditions, neoplasms, and renal disease is also caused by both decreased production and increased destruction of red cells.
Approach to the Diagnosis
Clinical evaluation should involve looking for occult blood in the stool, noting jaundice and splenomegaly, and taking a careful history to exclude drugs, toxins, blood loss, or nutrition as possible factors. The history should focus on possible causes of chronic blood loss such as tarry stools, hematemesis, or excessive menstruation. On physical examination, one may also note a smooth tongue (pernicious anemia), spoon nails (iron
deficiency anemia), and myxedema. The initial laboratory workup includes a CBC and differential, serum iron and iron-binding capacity or ferritin levels, serum B12, folic acid and homocysteine levels, chemistry profile, and serum haptoglobin level. The clinician should look at a blood smear. If these studies are not revealing, a hematologist should be consulted for a bone marrow examination.
Other Useful Tests
1. Sedimentation rate (infectious disease)
2. Red cell indices (pernicious anemia, iron deficiency anemia)
3. Reticulocyte count (hemolytic anemia)
4. Gastric analysis (pernicious anemia)
5. Schilling test (pernicious anemia)
6. Liver spleen scan (hemolytic anemia)
7. CT scan (liver or spleen size, malignancy)
8. Bone marrow biopsy (aplastic anemia)
9. Therapeutic trials (pernicious anemia, iron deficiency anemia)
10. Platelet count (aplastic anemia)
11. GI series (bleeding gastric ulcer, malignancy)
12. Barium enema (malignancy, colitis)
13. Endoscopy (malignancy, ulcer, diverticulitis)
14. Red blood cell survival (hemolytic anemia)
15. Serum erythropoietin (chronic renal disease)
16. Urinary, methylmalonic acid (pernicious anemia)
17. Peripheral blood smear (malaria, babesiosis)
In developing a list of diagnostic possibilities in cases of anemia, physiology is the key. Anemia may be caused by a decrease in red cell production, a break in the transport system (blood loss), or excessive red cell destruction.
Decreased production: This should bring to mind iron deficiency anemia, folate deficiency, and pernicious anemia. Production also is decreased when the bone marrow is infiltrated with leukemia or metastatic neoplasms. Replacement of the marrow by fibrous tissue (as occurs in myelofibrosis) also decreases production. Cirrhosis of the liver may be associated with anemia due to lack of ability to store B12, folic acid, and
iron, thus reducing production. Decreased production should also bring to mind aplastic anemia, toxic or idiopathic.
Break in the transport system (blood loss): Trauma to any part of the body may cause significant blood loss. Massive hematemesis associated with esophageal varices or gastric ulcers is also obvious. However, chronic GI blood loss from bleeding ulcers, neoplasms, and diverticulitis is not.
Also, insidious is the anemia associated with excessive menses or metrorrhagia. This can be dysfunctional or associated with fibroids or endometrial carcinoma and other tumors.
Increased destruction: This should prompt recall of the haemolytic anemias—hereditary or acquired. Sickle cell anemia, thalassemia (major and minor), and hereditary spherocytosis are the major genetic anemias.
Acquired hemolytic anemias include hemolytic anemias associated with lymphoma, leukemia, collagen disease, and idiopathic type. Hemolytic anemia may also be associated with infectious diseases such as malaria, Oroya fever, babesiosis, and septicemia. The hemolytic anemia associated with transfusion should not pose a diagnostic dilemma. Finally, toxins and drugs such as phenacetin, primaquine, and lead may induce a haemolytic anemia.
Miscellaneous conditions: A large spleen from whatever cause may induce anemia based on both excessive red cell destruction and decreased red cell production. Hypothyroidism is also associated with an anemia that may be due to multiple causes. Simple chronic anemia associated with chronic inflammatory conditions, neoplasms, and renal disease is also caused by both decreased production and increased destruction of red cells.
Approach to the Diagnosis
Clinical evaluation should involve looking for occult blood in the stool, noting jaundice and splenomegaly, and taking a careful history to exclude drugs, toxins, blood loss, or nutrition as possible factors. The history should focus on possible causes of chronic blood loss such as tarry stools, hematemesis, or excessive menstruation. On physical examination, one may also note a smooth tongue (pernicious anemia), spoon nails (iron
deficiency anemia), and myxedema. The initial laboratory workup includes a CBC and differential, serum iron and iron-binding capacity or ferritin levels, serum B12, folic acid and homocysteine levels, chemistry profile, and serum haptoglobin level. The clinician should look at a blood smear. If these studies are not revealing, a hematologist should be consulted for a bone marrow examination.
Other Useful Tests
1. Sedimentation rate (infectious disease)
2. Red cell indices (pernicious anemia, iron deficiency anemia)
3. Reticulocyte count (hemolytic anemia)
4. Gastric analysis (pernicious anemia)
5. Schilling test (pernicious anemia)
6. Liver spleen scan (hemolytic anemia)
7. CT scan (liver or spleen size, malignancy)
8. Bone marrow biopsy (aplastic anemia)
9. Therapeutic trials (pernicious anemia, iron deficiency anemia)
10. Platelet count (aplastic anemia)
11. GI series (bleeding gastric ulcer, malignancy)
12. Barium enema (malignancy, colitis)
13. Endoscopy (malignancy, ulcer, diverticulitis)
14. Red blood cell survival (hemolytic anemia)
15. Serum erythropoietin (chronic renal disease)
16. Urinary, methylmalonic acid (pernicious anemia)
17. Peripheral blood smear (malaria, babesiosis)
