Jay Tor

Because the symptoms of pernicious anemia are similar to those of many other diseases/conditions, there are quite a few tests that can be done in order to obtain an accurate diagnosis.

This is a link to the MedLinePlus blood/lymphatic system topics:
[url="http://www.nlm.nih.gov/medlineplus/bloodlymphaticsystem.html"]http://www.nlm.nih.gov/medlineplus/bloodlymphaticsystem.html[/url]

Here's a cut & paste from a medical Web site [emedicine]:

"Pernicious anemia is a chronic illness caused by impaired absorption of vitamin B-12 because of a lack of intrinsic factor (IF) in gastric secretions.

Lab Studies:

Peripheral blood - CBC Diff [differential]
Serum - indirect bilirubin, serum lactic dehydrogenase, other red blood cells, enzymes, and serum iron saturation, serum potassium, cholesterol, and skeletal alkaline phosphatase

Gastric: Total gastric secretions are decreased to about 10% of the normal amount. Most patients with pernicious anemia are achlorhydric, even with histamine stimulation. IF either is absent or markedly decreased.

Serum Cbl levels: homocysteine and methylmalonic acid indicating a tissue Cbl deficiency.

Elevated serum methylmalonic acid and homocysteine levels are found in patients with pernicious anemia. They probably are the most reliable test for Cbl deficiency in patients who do not have a congenital metabolism disorder. In the absence of an inborn error of methylmalonic acid metabolism, methylmalonic aciduria is a sign of Cbl deficiency.

Schilling test: The Schilling test measures Cbl absorption by increasing urine radioactivity after an oral dose of radioactive Cbl. The test is useful in demonstrating that the anemia is caused by an absence of IF and is not secondary to other causes of Cbl deficiency. Likewise, it is helpful because it identifies patients with classic pernicious anemia, even after they have been treated with vitamin B-12.
The test is performed by administering 0.5-2.0 mCi of radioactive cyanocobalamin in a glass of water to patients who have fasted. Two hours later, the patient is injected with 1 mg of unlabeled vitamin B-12 to saturate circulating transcobalamins. A 24-hour urine sample is collected, and the radioactivity in the specimen is measured and compared to a standard. Specimens showing less than 7% excretion in their urine are abnormal and indicate that poor absorption of the oral test dose occurred. If abnormal low values are obtained, a stage II Schilling test is performed. In this test, 60 mg of active hog IF is administered with the oral test dose to determine if this enhances the absorption of the vitamin B-12. If poor absorption of vitamin B-12 value is normalized, the patient presumably has classic pernicious anemia. If poor absorption is observed in a stage II test, search for other causes of vitamin B-12 malabsorption. Performance of a stage I Schilling test after 5 days of tetracycline therapy is used to exclude a blind loop as the etiology for Cbl deficiency (stage III). Similarly, if administration of trypsin or pancreatic enzyme with the radiolabeled test dose corrects the absorption of vitamin B-12, suspect pancreatic disease (stage IV).
False-positive Schilling test results are observed in patients with incomplete 24-hour urine collections or renal insufficiency, by using inactive IF, or because of neutralization of the IF in the stage II test by any IF antibodies in the stomach and severe ileal megablastosis. Occasionally patients are seen with Cbl deficiency and a normal stage I Schilling test. These patients can absorb vitamin B-12 in the fasting state, but not when it is presented with food. Adding the radiolabeled vitamin B-12 to egg white and testing the absorption usually reveals this cause of Cbl deficiency.

Clinical trial: The administration of a 1000 mcg of vitamin B-12 intramuscularly can be used as a clinical trial for suspected Cbl deficiency. Subjectively, this usually provides a marked sense of well-being in patients who are Cbl deficient within 24 hours after administration. Objectively, this produces a marked reticulocytosis, which is maximal in 5-7 days after the administration of the Cbl, and a correction of the anemia occurs in about 3 weeks."

Currently, there are 178 clinical trials on various types of anemia:
[url="http://clinicaltrials.gov/ct/gui/c/a1r/action/ChangeQuery?JServSessionIdzone_ct=1znij7 3sj1"]http://clinicaltrials.gov/ct/gui/c/a1r/action/ChangeQuery?JServSessionIdzone_ct=1znij7 3sj1[/url]