intrinsic-factor and Hematologic-Diseases

At one time, the diagnosis of a deficiency of vitamin B12 or folate was considered to be relatively straightforward. As knowledge has accumulated, the limitations of such tests as serum vitamin level measurements and the Schilling test have become apparent. With the development of newer tests, atypical and subclinical deficiency states have been recognized. In this review, available tests used in the diagnosis of vitamin B12 and folate deficiency are discussed, and a rational approach to the diagnosis of these deficiency states is presented.

Topics: Antibodies; Clinical Laboratory Techniques; Clinical Trials as Topic; Decision Trees; Diagnosis, Differential; Erythrocytes; Folic Acid Deficiency; Hematologic Diseases; Homocysteine; Humans; Intrinsic Factor; Methylmalonic Acid; Nervous System Diseases; Parietal Cells, Gastric; Primary Health Care; Schilling Test; Vitamin B 12; Vitamin B 12 Deficiency

Topics: Blood Coagulation; Blood Group Antigens; Blood Platelets; Blood Transfusion; Bone Marrow Examination; Cell Survival; Complement System Proteins; Erythrocyte Aggregation; Erythrocytes; Erythropoiesis; Feces; Folic Acid; Hematologic Diseases; Hematopoietic System; Hemolysis; Humans; Intrinsic Factor; Iron; Isoantibodies; Kinetics; Leukocytes; Mononuclear Phagocyte System; Radioisotopes; Vitamin B 12

Topics: Anemia, Pernicious; Blood Volume Determination; Chromium Isotopes; Erythrocyte Aging; Erythrocytes; Hematologic Diseases; Hematology; Humans; Intrinsic Factor; Iron; Iron Isotopes; Leukocytes; Organ Size; Radioisotope Dilution Technique; Radioisotopes; Radiometry; Radionuclide Imaging; Schilling Test; Serum Albumin, Radio-Iodinated; Spleen; Splenectomy

Parietal cell antibody is a marker for autoimmune gastritis. With identification of gastric H/K ATPase as its molecular target, ELISAs have been introduced. We compared performance of ELISA with immunofluorescence in a retrospective and prospective sera set and correlated the results with intrinsic factor antibody. In 138 retrospective sera selected for positivity or negativity for intrinsic factor antibody, 87 reacted with gastric H/K ATPase by Euroimm ELISA but only 62 reacted by immunofluorescencence.. Similar results were obtained with Inova ELISA with 78 positives that were also positive by Euroimm ELISA. In 161 prospective sera, 29 sera tested positive by ELISA compared to 24 by immunofluorescence. ELISA positive but immunofluoresnce negative sera are bona fide positives because a representative set of 16 sera reacted with both 95kD α and 60-90kDβ subunits of gastric H/K ATPase. ELISA values rose with age regardless of whether immunofluorescence tests were positive or negative. Of 53 sera containing antibody to intrinsic factor, 46/53 (87%) reacted to gastric H/K ATPase by ELISA. Taken together, the data indicates an enhanced detection rate by ELISA over immunofluorescence and validates it as a robust diagnostic assay for parietal cell antibody. As parietal cell antibody marks asymptomatic autoimmune gastritis that may progress to end stage gastric atrophy and haematological complications, and as autoimmune gastritis is associated with autoimmune thyroiditic and type 1 diabetes mellitus, early detection of parietal cell antibody by a sensitive ELISA will enable early follow-up of at risk subjects.

Topics: Adult; Age Factors; Aged; Aged, 80 and over; Autoantibodies; Autoimmune Diseases; Enzyme-Linked Immunosorbent Assay; Erythrocytes, Abnormal; Female; Fluorescent Antibody Technique; Gastritis; H(+)-K(+)-Exchanging ATPase; Hematologic Diseases; Humans; Intrinsic Factor; Male; Middle Aged; Parietal Cells, Gastric; Retrospective Studies; Vitamin B 12 Deficiency; Young Adult

The diagnostic interest of a search for anti-intrinsic factor antibodies is emphasized from the authors research on more than 200 patients or controls. Antibodies of type I, so-called blocking antibodies, were detected in 66% of cases where the diagnosis of pernicious anemia was made. Type II, so-called precipitating antibodies, were found in 47% of patients with antibodies of type I and only in the latter. Certain etiological factors, already noted in the world literature, were found, in particular the link with the female sex and with blood group A. The specificity of these antibodies is very great and false positives are exceptional. We did not find them in any of the 104 controls. They were observed, however, in 5 of the 56 patients where the diagnosis of pernicious anemia was not definite, but it is likely that, in these 5 cases, pernicious anemia existed with some other disease. Our study also showed the limits of other methods of investigation of this disease; hypovitaminimia B12 is often corrected by treatment without proper inductions and B12 malabsorption on the Schilling test may not be corrected by the addition of intrinsic factor.

Topics: Anemia, Macrocytic; Anemia, Pernicious; Antibody Specificity; Autoantibodies; Autoimmune Diseases; Blood Group Antigens; Diagnosis, Differential; False Positive Reactions; Female; Gastric Juice; Hematologic Diseases; Humans; Immunodiffusion; Intrinsic Factor; Male; Precipitins; Radioimmunoassay; Schilling Test; Sex Factors; Vitamin B 12

Topics: Adolescent; Adult; Cobalt Isotopes; Female; Hematologic Diseases; Humans; Intrinsic Factor; Leukemia; Male; Middle Aged; Radioisotope Dilution Technique; Vitamin B 12

Topics: Anemia, Hemolytic; Anemia, Hemolytic, Autoimmune; Anemia, Hypochromic; Anemia, Macrocytic; Antibodies; Cell Survival; Cobalt Isotopes; Diagnosis, Differential; Erythrocytes; Feces; Female; Folic Acid; Gastric Juice; Hematologic Diseases; Hemorrhage; Humans; Intrinsic Factor; Iron; Iron Isotopes; Plasma Volume; Radioimmunoassay; Radioisotope Dilution Technique; Radioisotopes; Radionuclide Imaging; Schilling Test; Spleen; Vitamin B 12; Whole-Body Counting

Topics: Anemia; Anemia, Pernicious; Autoantibodies; Hematologic Diseases; Humans; Intrinsic Factor; Pathology; Stomach; Thyroid Gland; Thyroiditis; Thyroiditis, Autoimmune; Vitamin B 12