Absorption Of Radioactive Vitamin B12 Research Articles

Use of radioisotope techniques in the clinical evaluation of patients with megaloblastic anemia

Because virtually all cases of vitamin B12 deficiency seen in this country are due to malabsorption, the availability of radioactive vitamin B12 for direct measurement of absorption of this essential nutrient has proved to be of great clinical value. These tests are useful not only in demonstrating vitamin B12 malabsorption but also often in defining the pathophysiological mechanism responsible for this abnormality. The urinary excretion test of Schilling remains the most useful test for vitamin B12 absorption. Minor precautions and modifications in technique make the test results more reliable and easier to interpret. The 8-hr plasma test for vitamin B12 absorption can no longer be considered acceptable. Some patients with vitamin B12 malabsorption have results in the normal range when studied by this method. Serum vitamin B12 assays utilizing radioactive vitamin B12 and the isotope dilution principle are not widely used and are useful screening tests. Low normal or borderline results observed in patients with clinical evidence suggestive of vitamin B12 deficiency should be interpreted with caution or confirmed by radioactive vitamin B12 absorption studies. Radioactive vitamin B12 can also be used for rapid, reliable assay of gastric intrinsic factor, antibody to intrinsic factor and unsaturated vitamin B12 serum. Methods using radioactive folate compounds for similar in vivo and in vitro studies are not yet applicable for routine use in nuclear medicine laboratories.

Congenital Pernicious Anemia with Coexistent Transitory Intestinal Malabsorption of Vitamin B12

Abstract Pernicious anemia with coexistent transitory intestinal malabsorption of vitamin B12 has been established in adults. In this report a child with congenital pernicious anemia was documented to have had transitory selective intestinal malabsorption of vitamin B12. The diagnosis of congenital pernicious anemia was established by the age of the patient, absence of intrinsic factor in gastric fluid, lack of antibodies to intrinsic factor and parietal cells, presence of HCl in gastric fluid, and normal gastric biopsy. The xylose excretion test, 72-hour fecal fat determination, upper gastrointestinal series, and biopsy of the jejunum were normal, but the Schilling test was abnormal with hog intrinsic factor of known potency on two occasions, indicating selective malabsorption of vitamin B12. Seven months after therapy the Schilling test was still abnormal without intrinsic factor, but was normal with both human and hog intrinsic factor. The normal absorption with intrinsic factor after therapy is indicative that the selective malabsorption which was originally present was probably a consequence of the vitamin B12 deficiency resulting from lack of intrinsic factor. In patients with abnormal radioactive vitamin B12 absorption tests with administration of intrinsic factor, coexistent pernicious anemia must be excluded by demonstration of intrinsic factor in gastric fluid.

54 Congenital Pernicious Anemia with Coexistent Transitory Intestinal Malabsorption of Vitamin B12

Pernicious anemia (PA) with coexistent transitory intestinal malabsorption of vitamin B12 has been documented in adults. This report is the first description of proven transitory selective intestinal malabsorption of vitamin B12 in congenital PA. A vitamin B12 responsive anemia was demonstrated in the patient, a 2 ½-year-old girl, by change in the bone marrow from megaloblastic hyperplasia to normoblastic hyperplasia 48 h after 5 μg of vitamin B12. No intrinsic factor (IF) was found in gastric fluid by in vitro assay before and again 4 and 6 weeks after therapy. Congenital PA was established by the age of the patient, absence of IF in gastric fluid, lack of antibodies to IF and parietal cells, presence of HCl in gastric fluid, and normal gastric biopsy. The xylose tolerance test, 72 h fecal fat determination, upper GI series, and biopsy of the jejunum were normal, but the Schilling test was abnormal with hog IF of known potency on two occasions, indicating selective malabsorption of vitamin B12. Six months after therapy the Schilling test was still abnormal without IF, but was normal with both human and hog IF. This normal absorption with IF after therapy is indicative that selective malabsorption was originally present, probably as a consequence of the vitamin B12 deficiency resulting from IF lack. In patients with abnormal radioactive vitamin B12 absorption tests with administration of IF, coexistent PA must be excluded by demonstration of IF in gastric fluid. (SPR)

The absorption of radioactive vitamin B12 and the secretion of hydrochloric acid in patients with atrophic gastritis

The absorption of radioactive vitamin B12 and the secretion of hydrochloric acid in patients with atrophic gastritis

The differential diagnosis of megaloblastic anaemia.

SUMMARYIn a series of 179 adult patients with megaloblastic anæmia there were 95 cases of pernicious anæmia and 38 cases of nutritional megaloblastic anæmia. These two conditions were difficult to distinguish clinically in many instances, especially if the patient was elderly and did not have an obviously faulty diet. The estimation of serum vitamin B12 concentration and radioactive vitamin B12 absorption tests were valuable in differential diagnosis ; but there was some overlap in results in the two groups, and these tests need interpretation in the light of other clinical and laboratory findings.Fourteen patients suffered from post‐gastrectomy megaloblastic anæmia. In five, the mechanism appeared to be lack of intrinsic factor secretion, in five, nutritional deficiency of folic acid, and in four, intestinal malabsorption.

Funicular myeloses. Considerations apropos of 110 cases

O autor, revendo o conceito atual da etiopatogenia das mieloses funiculares, conclui que, na determinação do processo desmielinizante, além da carência de vitamina B12 e da acloridria gástrica, participam outros fatores, carenciais e/ou alérgicos. Baseado no estudo de 110 casos com lesões gástricas constitucionais (100 casos) ou adquiridas (10 casos), o autor discute o problema do diagnóstico. São consideradas as síndromes periférica, funicular dorsal, "piramidal" e encefálica. É ressaltada a importância do exame da sensibilidade vibratória, particularmente por método quantitativo, que revelou, em elevada percentagem dos casos, distúrbios da palestesia também nas mãos. Entre os exames complementares, é salientado o valor do hemograma, do mielograma, da dosagem da acidez gástrica, da determinação da absorção da vitamina B12 radioativa; são também consideradas as alterações electrencefalográficas e do liqüido cefalorraqueano. Os resultados terapêuticos em 44 casos são avaliados através do estudo semiquantitativo da sintomatologia neurológica. Embora a vitamina B12 tenha proporcionado maiores índices de melhora, os demais medicamentos (extrato hepático, ácido fólico e adrenocorticotropina) também influenciaram favoravelmente o quadro neurológico. Em vista da pequena representação numérica da casuística nos grupos correspondentes aos quatro esquemas terapêuticos, o autor não emite conclusão definitiva. Salienta, porém, que êsses resultados demonstram a necessidade de prosseguir nos estudos sôbre a etiopatogenia das mieloses funiculares, no sentido de esclarecer as numerosas incógnitas que ainda perduram.

Rare malabsorption syndromes.

Excerpt New observations and new technics have made it possible in recent years to identify and to define previously poorly characterized or even unrecognized disorders of the small intestine. Cert...

Newer physiology of absorption from the intestine.

Article1 November 1959NEWER PHYSIOLOGY OF ABSORPTION FROM THE INTESTINERICHARD J. REITEMEIER, M.D.RICHARD J. REITEMEIER, M.D.Search for more papers by this authorAuthor, Article, and Disclosure Informationhttps://doi.org/10.7326/0003-4819-51-5-993 SectionsAboutPDF ToolsAdd to favoritesDownload CitationsTrack CitationsPermissions ShareFacebookTwitterLinkedInRedditEmail ExcerptIncrease in knowledge of the physiology of absorption by the gastrointestinal tract has not kept pace with advances in knowledge of renal and cardiac physiology. Contributing factors that, in part, explain this lack of progress include the relative inaccessibility of the gastrointestinal tract, its considerable length, the difficulty of sampling the portal blood, and the scarcity of adequate methods for measurement of absorption. In recent years, however, new tools and technics have appeared and have stimulated new interest and efforts. An attempt has been made in this discussion to survey only a part of the considerable literature in the field...Bibliography1. BensonChandlerVansteenhuyseGagnon JAGNFEJO: Studies concerning the site of fat absorption in the small intestine of the rat, Gastroenterology 30: 53, 1956. CrossrefMedlineGoogle Scholar2. BorgströmDahlqvistLundhSjövall BAGJ: Studies of intestinal digestion and absorption in the human, J. Clin. Investigation 36: 1521, 1957. CrossrefMedlineGoogle Scholar3. BeresWengerKirsner PJJB: The use of I131 triolein in the study of absorptive disorders in man, Gastroenterology 32: 1, 1957. CrossrefMedlineGoogle Scholar4. McKennaBourneMatzko RDRHA: The use of I131 labeled fat in the study of fat digestion and absorption in normal individuals and in patients with diseases of fat absorption, Gastroenterology 32: 17, 1957. CrossrefMedlineGoogle Scholar5. ShingletonBaylinIsleySandersRuffin WWGJJKAPJM: The evaluation of pancreatic function by use of I131 labeled fat, Gastroenterology 32: 28, 1957. CrossrefMedlineGoogle Scholar6. RuffinKeeverChearsShingletonBaylinIsleySanders JMICCWWGJJKAP: Further observations on the use of I131-labeled lipids in the study of diseases of the gastrointestinal tract, Gastroenterology 34: 484, 1958. CrossrefMedlineGoogle Scholar7. GrossmanJordan MIPH: The radio-iodinated triolein test for steatorrhea, Gastroenterology 34: 892, 1958. CrossrefMedlineGoogle Scholar8. KaplanEdidinFruinBaker EBDRCLA: Intestinal absorption of iodine131-labeled triolein and oleic acid in normal subjects and in steatorrhea, Gastroenterology 34: 901, 1958. CrossrefMedlineGoogle Scholar9. BerkowitzSklaroffWoldowJacobsLikoff DDAAGW: Blood absorptive patterns of isotopically-labeled fat and fatty acid, Ann. Int. Med. 50: 247, 1959. LinkGoogle Scholar10. MoertelOwenScudamoreWollaeger CGCAHHEE: Personal communication to the author. Google Scholar11. Van HandelZilversmit EDB: Limitation of radioiodine as a label for fat, J. Lab. and Clin. Med. 52: 831, 1958. MedlineGoogle Scholar12. BensonCulverRaglandJonesDrummeyBougas JAPJSCMGDE: The d-xylose absorption test in malabsorption syndromes, New England J. Med. 256: 335, 1957. CrossrefMedlineGoogle Scholar13. HalstedSwendseidLewisGasster JAMEPMM: Mechanisms involved in the development of vitamin B12 deficiency, Gastroenterology 30: 21, 1956. CrossrefMedlineGoogle Scholar14. ScudamoreHagedornWollaegerOwen HHABEECA: Diverticulosis of the small intestine and macrocytic anemia with report of two cases and studies on absorption of radioactive vitamin B12 , Gastroenterology 34: 66, 1958. CrossrefMedlineGoogle Scholar15. Glass GB: Intestinal absorption and hepatic uptake of vitamin B12 in diseases of the gastrointestinal tract, Gastroenterology 30: 37, 1956. CrossrefMedlineGoogle Scholar16. GräsbeckKanteroSiurala RIM: Influence of calcium ions on vitamin B12 absorption in steatorrhea and pernicious anaemia, Lancet 1: 234, 1959. CrossrefMedlineGoogle Scholar17. BoothMollin CCDL: The site of absorption of vitamin B12 in man, Lancet 1: 18, 1959. CrossrefMedlineGoogle Scholar18. VisscherFetcherCarrGregorBusheyBarker MBESCWHPMSDE: Isotopic tracer studies on the movement of water and ions between intestinal lumen and blood, Am. J. Physiol. 142: 550, 1944. CrossrefGoogle Scholar19. ScholerCode JFCF: Rate of absorption of water from stomach and small bowel of human beings, Gastroenterology 27: 565, 1954. CrossrefMedlineGoogle Scholar20. ScholerOrvisHigginsCode JFALJACF: Use of dual isotopes in determination of rates of absorption in intact animals, Am. J. Physiol. 183: 659, 1955. Google Scholar21. ReitemeierCodeOrvis RJCFAL: Comparison of rate of absorption of labeled sodium and water from upper small intestine of healthy human beings, J. Appl. Physiol. 10: 256, 1957. CrossrefMedlineGoogle Scholar22. LeeCodeScholer PRCFJF: The influence of varying concentrations of sodium chloride on the rate of absorption of water from the stomach and small bowel of human beings, Gastroenterology 29: 1008, 1955. CrossrefMedlineGoogle Scholar23. HigginsLeeScholerReitemeierCodeWollaeger JAPRJFRJCFEE: Absorption of water and sodium from the small intestine of patients with nontropical sprue, J. Clin. Investigation 36: 265, 1957. CrossrefMedlineGoogle Scholar24. HigginsCodeOrvis JACFAL: The influence of motility on the rate of absorption of sodium and water from the small intestine of healthy persons, Gastroenterology 31: 708, 1956. CrossrefMedlineGoogle Scholar This content is PDF only. To continue reading please click on the PDF icon. Author, Article, and Disclosure InformationAffiliations: Rochester, Minnesota*Received for publication May 16, 1959.Presented at the Fortieth Annual Session of The American College of Physicians, Chicago, Illinois, April 22, 1959.From the Section of Medicine, Mayo Clinic and Mayo Foundation, Rochester, Minnesota.The Mayo Foundation is a part of the Graduate School of the University of Minnesota.Requests for reprints should be addressed to Section of Publications, Mayo Clinic, Rochester, Minnesota. PreviousarticleNextarticle Advertisement FiguresReferencesRelatedDetails Metrics Cited byPHARMACOKINETICS AS A BASIC MEDICAL PROBLEM 1 November 1959Volume 51, Issue 5Page: 993-1002KeywordsBileBloodCalciumDigestionGastrointestinal tractGraduate medical educationIleumNutrientsRenal physiology ePublished: 1 December 2008 Issue Published: 1 November 1959 PDF downloadLoading ...

Observations on vitamin B12 absorption in primary pernicious anemia during administration of adrenocortical steroids.

IT has been adequately demonstrated that the basic defect in pernicious anemia is failure of the mucosal cells in the fundal portion of the stomach to secrete intrinsic-factor substance. This factor is necessary for normal absorption of vitamin B12 from the small intestine. A few reports in the literature have shown suboptimal reticulocyte responses in patients with pernicious anemia in relapse receiving ACTH and cortisone.1 2 3 4 We have recently studied the effect of adrenocortical-steroid administration on the absorption of radioactive vitamin B12 in classic primary pernicious anemia utilizing the Schilling test, which measures the absorption of orally administered radioactive . . .

Diagnostic value of radioactive vitamin B12.

SummaryThe intestinal absorption of orally administered radioactive vitamin B12 has been studied by a modified urinary excretion test. Subjects were given a standard oral dose of 0.6 microgramme of 60Co vitamin B12. The mean 48‐hour urinary radioactivity in 22 control individuals was 23.9% of the oral dose. In five patients with megaloblastic anæmia due to folic acid deficiency, a similar mean excretion of 22 4% was found. In 15 patients with pernicious anæmia in relapse, impaired absorption of radioactive vitamin B12 was demonstrated. The mean urinary radioactivity was 2.4%. This was increased to 19.6% when the oral dose was given with an intrinsic factor preparation.Twenty‐five patients on maintenance therapy because of a previous diagnosis of pernicious anæmia were studied. The diagnosis was disproved in to patients, who were shown to be able to absorb orally administered radioactive vitamin B12 normally.

Megaloblastic anaemia associated with anticonvulsant drug therapy.

SummaryAn epileptic boy of 16 years developed megaloblastic anæmia while being treated with primidone and phenytoin. There was an optimal hæmatological response to folic acid therapy. Laboratory investigations showed a normal serum concentration of vitamin B12 and normal radioactive vitamin B12 absorption. This is the thirty‐third reported case of megaloblastic anæmia associated with anticonvulsant therapy.Certain features common to the majority of these cases suggest that a folic acid deficiency or a derangement of folic acid metabolism is responsible for the megaloblastic anæmia. All 20 patients treated with folic acid responded optimally. Eight patients are reported to have responded to vitamin B12, one to liver extract and four to a combination of folic acid and vitamin B12.It is suggested that the anticonvulsant drugs have an antifolic acid action which is too mild to produce megaloblastic anæmia in the majority of epileptics unless one or more co‐factors operate. A suboptimal folic acid intake is postulated as the main co‐factor in at least five of the 20 cases in which there was a response to folic acid and perhaps also in some of the cases in which a response has been reported to vitamin B12. In one case repeated hæmorrhage, in another pregnancy and in a third case a possible latent steatorrhœa are postulated as additional co‐factors.

Incidence of megaloblastic anemia after subtotal gastrectomy.

MEGALOBLASTIC anemia indistinguishable from pernicious anemia is a late but inevitable sequela of total gastrectomy and probably of proximal subtotal gastrectomy with esophagoantrostomy.1 2 3 This conclusion was reached with the use of the absorption of radioactive vitamin B12 as an assay of intrinsic factor in the gastrointestinal tract and the determination of the incidence of megaloblastosis after total gastrectomy when all patients undergoing this operation at one institution were followed for more than three years. Megaloblastic anemia has been reported after distal subtotal gastrectomy, but the true incidence has never been investigated. Anemia after subtotal gastrectomy is common (as high . . .

Differentiation of macrocytic anemias and diagnosis of pernicious anemia and sprue in remission by accelerated measurement of hepatic uptake of radioactive Co60B12.

Excerpt The differential diagnosis of various types of macrocytic anemia often presents difficult clinical problems. Many cases of dietary folic acid or B12deficiency and sprue cannot be distinguis...

Absorption of radioactive vitamin B12 after total gastrectomy; relation to macrocytic anemia and to the site of origin of Castle's intrinsic factor.

Twenty-five years ago Castle1 showed that the oral administration of normal gastric juice mixed with beef muscle to patients with pernicious anemia resulted in a hematologic response, although neither substance was effective by itself. This led to the concept that pernicious anemia is caused by deficiency of a gastric or "intrinsic factor" that normally reacts with an "extrinsic" or food factor to produce a substance necessary for hematopoiesis. The intrinsic factor was found to be present not only in normal human gastric juice but also in the intestinal and gastric mucosa of other animal species, particularly swine.2 Since 1929 a . . .