RESUMEN
INTRODUCTION: The aim of the study was to determine the frequency of occurrence of antibodies participating in the development of endocrine diseases in patients with autoimmune haematopoietic disease, thus documenting the potential suitability of specific diagnostic and screening tests. MATERIAL AND METHODS: The study group consisted of 124 persons (men and women) with newly diagnosed pernicious anaemia (PA) and a control group (C) of 41 healthy people. Antibodies against: intrinsic factor (IFAb), gastric parietal cells (APCA), thyroid peroxidase (TPOAb), thyroglobulin (TgAb), adrenal cortex (AdrenalAb), and pituitary anterior lobe (PituitaryAb) were determined in the blood. RESULTS: 1. The risk of the presence of antibodies against endocrine glands in patients with PA can be classified in order: TPOAb and/or TgAb - 41.1%, TPOAb - 36.3%, TgAb - 25.0%, TPOAb and TgAb - 20.2%, AdrenalAb - 1.6%, PituitaryAb - 0.8%. 2. TPOAb and/or TgAb (mainly TPOAb) are more frequently present in patients with PA, who have IFAb and/or APCA. This correlation is most evident in patients with simultaneous occurrence of IFAb and APCA. 3. Among patients with PA, the simultaneous presence of antibodies IFAb and/or APCA with TPOAb and/or TgAb antibodies is most likely in women over 45 years of age. 4. In group C, 12% had at least one of two antithyroid antibodies (TgAb twice as often as TPOAb), and 2.4% had both. AdrenalAb and PituitaryAb are not found in healthy persons. CONCLUSIONS: In patients with PA, a screening for autoimmune thyroid disease is justified, which should first involve the determination of TPOAb (further TgAb) in the blood. The assessment of antithyroid antibodies should be recommended primarily to patients with PA, who have IFAb and/or APCA, and in particular those with concurrent IFAb and APCA.
Asunto(s)
Anemia Perniciosa/sangre , Anemia Perniciosa/inmunología , Anticuerpos/sangre , Adulto , Factores de Edad , Anemia Perniciosa/diagnóstico , Autoanticuerpos/sangre , Estudios de Casos y Controles , Ensayo de Inmunoadsorción Enzimática , Femenino , Humanos , Factor Intrinseco/sangre , Yoduro Peroxidasa/sangre , Masculino , Persona de Mediana Edad , Células Parietales Gástricas/inmunología , Tiroglobulina/sangreRESUMEN
Pernicious anaemia is an autoimmune disease caused by intrinsic factor antibody; it leads to vitamin B12 deficiency and is marked by ineffective erythropoiesis. Haematological features reveal macrocytosis, hyperchromasia and hypersegmented neutrophils. Schistocytes are typically seen in microangiopathy, such as in thrombotic thrombocytopaenic purpura (TTP)/haemolytic uraemic syndrome or disseminated intravascular haemolysis (DIC). We report a case of a patient with severe anaemia who presented to the emergency room. Peripheral smear revealed macrocytosis, hypersegmented neutrophils and marked schistocytosis. The patient also had high reticulocyte count with high serum lactate dehydrogenase, elevated D-dimer, low fibrinogen and low haptoglobin. Vitamin B12 level came back low and the presence of intrinsic factor antibody confirmed pernicious anaemia. ADAMTS13 level was noted to be mildly reduced, which raised the suspicion of the association of acquired TTP with pernicious anaemia. Acquired TTP is another autoimmune disorder and its association with pernicious anaemia needs further evaluation.
Asunto(s)
Proteínas ADAM/sangre , Anemia Perniciosa/complicaciones , Autoanticuerpos/sangre , Eritrocitos Anormales , Factor Intrinseco/sangre , Púrpura Trombocitopénica Trombótica/complicaciones , Vitamina B 12/sangre , Proteína ADAMTS13 , Anciano , Anemia Macrocítica/sangre , Anemia Macrocítica/complicaciones , Anemia Macrocítica/diagnóstico , Anemia Perniciosa/sangre , Anemia Perniciosa/diagnóstico , Enfermedades Autoinmunes/sangre , Recuento de Eritrocitos , Eritropoyesis , Femenino , Productos de Degradación de Fibrina-Fibrinógeno/metabolismo , Fibrinógeno/metabolismo , Haptoglobinas/metabolismo , Síndrome Hemolítico-Urémico/sangre , Síndrome Hemolítico-Urémico/complicaciones , Humanos , L-Lactato Deshidrogenasa/sangre , Neutrófilos , Púrpura Trombocitopénica Trombótica/sangre , Púrpura Trombocitopénica Trombótica/diagnósticoRESUMEN
OBJECTIVE: To investigate the correlation between insulin resistance (IR) and serum 25-OH-Vit D concentrations and hormonal parameters in lean women with polycystic ovary syndrome (PCOS). PATIENTS AND METHODS: 50 lean women with PCOS and 40 body mass index (BMI) matched controls were compared in terms of fasting insulin and glucose, homeostatic model assessment insulin resistance (HOMA-IR), 25-OH-Vit D, high sensitivity C-reactive protein (hs-CRP), luteinizing hormone (LH), follicle-stimulating hormone (FSH), total testosterone, dehydroepiandrosterone sulfate (DHEA-S), total cholesterol, high density lipoprotein (HDL), low density lipoprotein (LDL), triglycerides and Ferriman-Gallway (FG) scores. Correlation analyses were performed between HOMA-IR and metabolic and endocrine parameters. RESULTS: 30% of patients with PCOS demonstrated IR. Levels of 25-OH-Vit D, hsCRP, cholesterol, HDL, LDL, triglyceride and fasting glucose did not differ between the study and control groups. Fasting insulin, HOMA-IR, LH, total testosterone, and DHEA-S levels were higher in PCOS group. HOMA-IR was found to correlate with hs-CRP and total testosterone but not with 25-OH-Vit D levels in lean patients with PCOS. CONCLUSIONS: An association between 25-OH-Vit D levels and IR is not evident in lean women with PCOS. hs-CRP levels do not indicate to an increased risk of cardiovascular disease in this population of patients. Because a strong association between hyperinsulinemia and hyperandrogenism exists in lean women with PCOS, it is advisable for this population of patients to be screened for metabolic disturbances, especially in whom chronic anovulation and hyperandrogenism are observed together.
Asunto(s)
Resistencia a la Insulina/fisiología , Factor Intrinseco/sangre , Síndrome del Ovario Poliquístico/sangre , Delgadez/sangre , Deficiencia de Vitamina D/sangre , Vitamina D/sangre , Adulto , Biomarcadores/sangre , Índice de Masa Corporal , Femenino , Humanos , Insulina/sangre , Síndrome del Ovario Poliquístico/diagnóstico , Testosterona/sangre , Delgadez/diagnóstico , Deficiencia de Vitamina D/diagnósticoRESUMEN
OBJECTIVES: To systematically assess five automated cobalamin assays for intrinsic factor binding antibody (IFBA)-induced interference using pooled serum. METHODS: Six pools created from IFBA-negative and IFBA-positive serum representing low, normal, and high cobalamin concentrations were analyzed before and after polyethylene glycol (PEG) precipitation of immunoglobulins on five cobalamin assays: the Centaur XP (Siemens Healthcare Diagnostics, Tarrytown, NY), IMMULITE 2000 (Siemens Healthcare Diagnostics), ARCHITECT i2000SR (Abbott Diagnostics, Abbott Park, IL), UniCel Dxl 800 (Beckman Coulter, Chaska, MN), and Modular E170 (Roche Diagnostics, Indianapolis, IN). RESULTS: Cobalamin concentrations before and after PEG treatment were similar, almost all within a 30% total allowable error, with no difference in pattern between the IFBA-negative and IFBA-positive pools regardless of the cobalamin concentration. CONCLUSIONS: Our results suggest that, under optimal conditions, the five automated cobalamin assays assessed are not susceptible to IFBA-mediated interference.
Asunto(s)
Anticuerpos/inmunología , Inmunoensayo , Factor Intrinseco/sangre , Vitamina B 12/análisis , Automatización/métodos , Humanos , Inmunoensayo/métodos , Valores de Referencia , Reproducibilidad de los Resultados , Vitamina B 12/inmunologíaRESUMEN
OBJECTIVE: To evaluate the presence of intrinsic factor antibody in vitamin B12 deficient patients. STUDY DESIGN: Cross-sectional, observational study. PLACE AND DURATION OF STUDY: Fauji Foundation Hospital, Foundation University Medical College and Armed Forces Institute of Pathology, Rawalpindi, from January 2011 to June 2012. METHODOLOGY: A total of 120 patients of megaloblastic anaemia were selected on the basis of low serum vitamin B12 level. The intrinsic factor antibody tests were performed by ELISA method. The patients were considered positive or negative on the basis of presence or absence of intrinsic factor antibody respectively. The data was analyzed by using SPSS version 14. RESULTS: Pernicious anaemia with intrinsic factor deficiency was found in 13.3% in 120 vitamin B12 deficient patients. The mean age of patients of pernicious anaemia was 41.5 years, with a male to female ratio of 1:2.5. It was relatively more common in older age (17% in age more than 60 years) as compared to other age groups. CONCLUSION: Frequency of pernicious anaemia in megaloblastic anaemia was 13.3%. The male to female ratio was 1:2.5 and it was relatively more common in age group of more than 60 years.
Asunto(s)
Anemia Perniciosa/congénito , Anemia Perniciosa/etiología , Autoanticuerpos/sangre , Factor Intrinseco/deficiencia , Factor Intrinseco/inmunología , Deficiencia de Vitamina B 12/complicaciones , Vitamina B 12/sangre , Adulto , Anciano , Anciano de 80 o más Años , Anemia Perniciosa/sangre , Anemia Perniciosa/epidemiología , Estudios Transversales , Ensayo de Inmunoadsorción Enzimática , Femenino , Humanos , Factor Intrinseco/sangre , Masculino , Persona de Mediana Edad , Pakistán/epidemiología , Prevalencia , Distribución por Sexo , Deficiencia de Vitamina B 12/sangre , Deficiencia de Vitamina B 12/epidemiologíaRESUMEN
OBJECTIVES: Atrophic body gastritis (ABG) is an autoimmune condition eventually manifesting itself as pernicious anemia (PA). Parietal cell autoantibodies (PCAs) and intrinsic factor autoantibodies (IFAs) are considered characteristics of these conditions. Recent studies on IFA and PCA frequency with respect to cobalamin deficiency in biopsy-proven ABG patients are lacking. We addressed this issue using new enzyme-linked immunosorbent assay (ELISA)-based assays. METHODS: Sera from 165 patients with histologically diagnosed ABG and 113 controls were tested for IFA and PCA using ELISA. A total of 81 ABG patients had cobalamin deficiency and macrocytic anemia (Group 1-PA), 36 had cobalamin deficiency without macrocytic anemia (Group 2), and 48 had normal cobalamin levels (Group 3). RESULTS: IFAs were detected in 44/165 ABG patients (27% sensitivity) and in 0/113 controls (100% specificity). PCAs were detected in 134 ABG patients (81% sensitivity) and in 11 controls (90% specificity). In Group 1, IFAs showed 37% sensitivity and 100% specificity, whereas PCAs showed 81% sensitivity and 90% specificity. Combining IFA and PCA testing increased the sensitivity to 61% in all ABG patients and to 73% in Group 1, while maintaining 100% specificity. CONCLUSIONS: IFAs are 100% specific for biopsy-proven ABG and occurred in 27% of patients. PCAs occurred in 81% of ABG patients and in 10% of controls. Combining IFA and PCA testing significantly increases their diagnostic performance for ABG and PA, yielding a 73% sensitivity for PA. The non-invasive combined PCA and IFA assessment may be useful in selecting patients at risk for autoimmune gastritis to be confirmed by gastroscopic-histologic examination.
Asunto(s)
Autoanticuerpos/sangre , Gastritis Atrófica/sangre , Gastritis Atrófica/complicaciones , Factor Intrinseco/sangre , Células Parietales Gástricas/inmunología , Deficiencia de Vitamina B 12/sangre , Deficiencia de Vitamina B 12/complicaciones , Adulto , Femenino , Gastritis Atrófica/diagnóstico , Humanos , Masculino , Persona de Mediana EdadRESUMEN
To study the clinical and hematologic features of pernicious anemia in Chinese, we describe 181 Chinese with megaloblastic anemia and low serum cobalamin, in association with either classic Schilling test results (82 patients) or the presence of serum antibody to intrinsic factor (99 patients), encountered in a regional hospital in Hong Kong from May 1994 to May 2005. The median age was 75 years (range, 32-95 yr) and the male to female ratio was 1:1.5. The chief presenting feature was anemia, and fewer than 10% of patients presented predominantly with neurologic deficit. Gastric biopsies of 109 patients showed glandular atrophy in 73, endocrine cell hyperplasia in 5, polyps in 14, adenocarcinoma in 1, and chronic gastritis in the rest. Gastric adenocarcinoma occurred in 1.7% of patients after a median follow-up of 35 months (range, 0.5-132 mo). Diabetes mellitus occurred in 24% of patients and thyroid disease in 7%. No specific ABO blood group was associated with pernicious anemia. Serum antibody to intrinsic factor (73%) occurred more frequently than serum antibody to gastric parietal cell (65%) (p=0.353). The frequency of serum antibody to gastric parietal cell was higher in male (78%) than in female patients (53%) (p=0.018). Pernicious anemia is a major cause of megaloblastic anemia in Chinese.
Asunto(s)
Anemia Perniciosa/diagnóstico , Anemia Perniciosa/etnología , Pueblo Asiatico , Células Parietales Gástricas/inmunología , Adulto , Anciano , Anciano de 80 o más Años , Anemia Perniciosa/fisiopatología , Femenino , Fluoroinmunoensayo , Hong Kong/epidemiología , Hospitalización , Humanos , Factor Intrinseco/sangre , Factor Intrinseco/deficiencia , Masculino , Persona de Mediana Edad , Estudios Prospectivos , Medición de Riesgo , Factores de Riesgo , Prueba de Schilling , Pruebas Serológicas , Vitamina B 12/sangreRESUMEN
Diabetes is a well-recognised risk factor for atherosclerotic cardiovascular disease and in fact most diabetic patients die from vascular complications. The Diabetes Control and Complications Trial (DCCT) and the U.K. Prospective Diabetes Study (UKPDS) indicate a consistent relationship between hyperglycaemia and the incidence of chronic vascular complications in patients with diabetes. Platelets are essential for haemostasis, and abnormalities of platelet function may cause vascular disease in diabetes. Diabetic patients have hyperreactive platelets with exaggerated adhesion, aggregation and thrombin generation. In summary, the entire coagulation cascade is dysfunctional in diabetes. This review provides a comprehensive overview of the physiological role of platelets in maintaining haemostasis and of the pathophysiological processes that contribute to platelet dysfunction in diabetes and associated cardiovascular diseases, with special emphasis on proteomic approaches and leukocyte-platelet cross-talk.
Asunto(s)
Plaquetas/fisiología , Enfermedades Cardiovasculares/prevención & control , Complicaciones de la Diabetes/complicaciones , Leucocitos/fisiología , Proteínas/metabolismo , Animales , Coagulación Sanguínea , Enfermedades Cardiovasculares/sangre , Enfermedades Cardiovasculares/etiología , Comunicación Celular , Ensayos Clínicos como Asunto , Complicaciones de la Diabetes/sangre , Genómica , Hemostasis , Humanos , Factor Intrinseco/sangre , Activación Plaquetaria , Agregación Plaquetaria , Proteínas/genética , Proteómica , Factores de RiesgoRESUMEN
GOALS: To determine whether serum vitamin B12 levels in non-vitamin B12 deficient healthy adults correlate with serological evidence of H. pylori infection. BACKGROUND: An association between H. pylori infection and vitamin B12 deficiency has been recently reported. STUDY: 133 adults, presenting to a community based primary care clinic who met the following exclusion criteria; history of H. pylori eradication or antacid use, liver disease, inflammatory bowel disease, previous gastrointestinal surgery, a vegetarian diet or multivitamin supplementation were studied. Blood was drawn for a complete blood count, serum vitamin B12, gastrin, folic acid and H. pylori IgG antibodies. Subjects with vitamin B12 < or = 145 ng/mL (deficient range) were excluded. RESULTS: Of 133 subjects 96 (72.2%) were seropositive for H. pylori IgG antibodies (HP+). Age of HP(+) subjects did not differ from that of seronegative subjects (HP-); 52.8 +/- 1.6 mean +/- SE versus 49.2 +/- 2.9 ( = NS). Prevalence of HP seropositivity was significantly higher among subjects with borderline (>145-180 pg/mL) or low normal (>180-250 pg/mL) vitamin B12 levels than among those with vitamin B12 > 250 pg/mL; among 25 subjects with vitamin B12 > 145-180 pg/mL 92% were seropositive and among 47 subjects with vitamin B12 > 180-250 pg/mL 89% were seropositive as compared with 31/61 (51%) of subjects with B12 > 250 pg/mL, Fisher exact test < 0.0001. Vitamin B12 levels did not correlate with age (r = -0.07). Gastrin levels (pg/mL) did not differ significantly between groups; 70.2 +/- 5.8 in HP(+) versus 56.0 +/- 12.4 in HP(-). CONCLUSIONS: The higher prevalence of H. pylori infection among subjects with serum vitamin B12 levels that are within the lower end of the normal range suggests a causal relationship between H pylori infection and vitamin B12 levels in healthy adults.
Asunto(s)
Infecciones por Helicobacter/sangre , Helicobacter pylori , Vitamina B 12/sangre , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Biomarcadores/sangre , Índices de Eritrocitos , Femenino , Ácido Fólico/sangre , Gastrinas/sangre , Gastrinas/inmunología , Infecciones por Helicobacter/diagnóstico , Infecciones por Helicobacter/epidemiología , Hematócrito , Hemoglobinas/metabolismo , Humanos , Inmunoglobulina G/inmunología , Factor Intrinseco/sangre , Factor Intrinseco/inmunología , Masculino , Persona de Mediana Edad , Células Parietales Gástricas/inmunología , Células Parietales Gástricas/metabolismo , Prevalencia , Valores de Referencia , Estudios Seroepidemiológicos , Estadística como AsuntoRESUMEN
Intrinsic factor (IF) is a vitamin B12 binding protein that is secreted from the gastric mucosa. We tested secretagogues which stimulate IF secretion in rat gastric perfusion and found that carbachol and cholecystokinin octapeptide (CCK-8) stimulated secretion, but histamine and tetragastrin did not. To confirm these results, we examined IF secretion from isolated rat chief cells. For this purpose, we established an enzyme immunoassay (EIA) using an avidin-biotin peroxidase complex to measure small amounts of IF. To prepare an anti-rat IF, IF was isolated from the stomach, and was injected into a rabbit for immunization. Rat gastric chief cells were isolated from the gastric mucosa with Dispase and a Percoll gradient centrifugation, and were cultured. We examined the effects of chemicals by adding them to culture dishes of chief cells in a CO2 incubator. Released IF in culture medium was determined by EIA. Carbachol, CCK-8 and secretin stimulated IF secretion from cultured chief cells, while histamine and tetragastrin did not; Forskolin and A23187 also stimulated the secretion. We concluded that carbachol and CCK-8 stimulated IF secretion via an increase of intracellular Ca2+ concentration and that secretin did so via a cAMP accumulation.
Asunto(s)
Mucosa Gástrica/metabolismo , Factor Intrinseco/metabolismo , Transcobalaminas/metabolismo , Animales , Western Blotting , Calcimicina/farmacología , Calcio/metabolismo , Carbacol/farmacología , Células Cultivadas , Centrifugación por Gradiente de Densidad , Cromatografía de Afinidad , Colforsina/farmacología , AMP Cíclico/metabolismo , Electroforesis en Gel de Poliacrilamida , Mucosa Gástrica/citología , Mucosa Gástrica/efectos de los fármacos , Histamina/farmacología , Técnicas para Inmunoenzimas , Inmunohistoquímica , Factor Intrinseco/sangre , Factor Intrinseco/aislamiento & purificación , Riñón/metabolismo , Hígado/metabolismo , Conejos , Ratas , Sincalida/farmacología , Bazo/metabolismo , Glándula Submandibular/metabolismo , Tetragastrina/farmacología , Distribución Tisular , Transcobalaminas/análisisRESUMEN
Recent evidence suggests that vitamin B12 deficiency in the elderly is more than classic pernicious anemia. Instead, it is a continuum from negative B12 balance to frank deficiency, which can be detected by low serum B12 levels long before changes occur in hemoglobin levels. Current findings in the literature suggest that subtle B12 deficiency is indeed clinically significant. Treatment may prevent significant neurologic and/or hematologic disease.
Asunto(s)
Transcobalaminas/metabolismo , Deficiencia de Vitamina B 12/tratamiento farmacológico , Vitamina B 12/uso terapéutico , Anciano , Anciano de 80 o más Años , Esquema de Medicación , Humanos , Factor Intrinseco/sangre , Prueba de Schilling , Vitamina B 12/administración & dosificación , Vitamina B 12/sangre , Deficiencia de Vitamina B 12/sangre , Deficiencia de Vitamina B 12/diagnósticoRESUMEN
A protein-bound Schilling test incorporating chick serum was used to study 16 elderly vitamin B12-deficient inpatients. Thirteen of these also underwent standard Schilling tests. They were compared with an age-matched control group of non-deficient inpatients. The lower limit of normal for assimilation of protein-bound vitamin B12 was 0.7%. Fourteen out of 16 deficient patients assimilated protein-bound vitamin B12 subnormally. Twelve of these were fully Schilling tested. Five assimilated free B12 normally, and five responded to intrinsic factor. One patient did not respond to intrinsic factor and had jejunal diverticulosis and one could not be categorized. One of two patients with normal assimilation had a borderline vitamin B12 intake. No subjects had neurological sequelae and only three were anaemic. In this population, B12 deficiency is usually asymptomatic but nearly always results from impaired assimilation possibly justifying replacement therapy. Schilling testing only affects treatment if there is other evidence of small-bowel dysfunction.
Asunto(s)
Deficiencia de Vitamina B 12/etiología , Factores de Edad , Anciano , Anciano de 80 o más Años , Proteínas Portadoras/sangre , Femenino , Ferritinas/sangre , Ácido Fólico/sangre , Humanos , Factor Intrinseco/sangre , Masculino , Persona de Mediana Edad , Distribución Aleatoria , Prueba de Schilling , Deficiencia de Vitamina B 12/sangre , Deficiencia de Vitamina B 12/diagnósticoRESUMEN
The ratio of pepsinogen I to pepsinogen II in the circulation decreases progressively with increasing severity of atrophic gastritis of the fundic gland mucosa. Fasting blood was obtained from 359 free-living and institutionalized elderly people (age range, 60 to 99 years). A pepsinogen I/pepsinogen II ratio less than 2.9, indicating atrophic gastritis, was found in 113 (31.5%) subjects. The prevalence of atrophic gastritis increased significantly with advancing age (P less than .05). Within the atrophic gastritis group, 84 had a pepsinogen I level greater than or equal to 20 micrograms/L, indicating mild to moderate atrophic gastritis, and 29 had a pepsinogen I level less than 20 micrograms/L, indicating severe atrophic gastritis or gastric atrophy. A significant increase in the prevalences of elevated serum gastrin levels (P less than .005), low serum vitamin B12 levels (P less than .005), circulating intrinsic factor antibody (P less than .005), and anemia (P less than .025) was observed with stepwise increases in severity of atrophic gastritis. Subjects with atrophic gastritis exhibited a lower mean serum vitamin B12 level (P less than .05) and a higher mean folate level (P less than .05), but no difference was detected in mean hemoglobin levels or serum levels of iron, ferritin, retinol or alpha-tocopherol. It is concluded that serum pepsinogen I and pepsinogen II levels can be used to determine the prevalence and severity of atrophic gastritis, that atrophic gastritis is common in an elderly population, and that atrophic gastritis is associated with vitamin B12 deficiency and anemia. Further, higher folate levels in atrophic gastritis may be related to an accumulation of 5-methyl tetrahydrofolate in serum due to vitamin B12 deficiency and/or greater folate synthesis by the intestinal flora resulting from bacterial overgrowth secondary to hypo- or achlorhydria.
Asunto(s)
Anciano de 80 o más Años , Envejecimiento , Gastritis Atrófica/sangre , Gastritis/sangre , Pepsinógenos/sangre , Anciano , Boston , Femenino , Gastrinas/sangre , Gastritis Atrófica/diagnóstico , Gastritis Atrófica/epidemiología , Gastritis Atrófica/etiología , Hemoglobinas , Humanos , Factor Intrinseco/sangre , Masculino , Persona de Mediana Edad , Estado Nutricional , Deficiencia de Vitamina B 12/sangreRESUMEN
The clinical importance of a reliable human serum vitamin B12 assay to aid the diagnosis of pernicious anemia (PA) cannot be overemphasized. Our review of the literature indicates that a reference method for the quantitation of serum vitamin B12 (serum B12) with the required accuracy, precision and rapidity has not been reported to-date. Controversies, debates and criticisms over human serum B12 assays (especially commercial kits) have been common-place. Various methods of quantitation of B12 reviewed in this communication include: microbiological, radioisotopic, high-performance liquid chromatography (HPLC) and the most recent radioimmunoassay (RIA) techniques. This review attempts to provide awareness of the limitations of these methods and establishes the base for eventual development of a B12 reference method in our laboratory.
Asunto(s)
Vitamina B 12/sangre , Unión Competitiva , Bioensayo , Cromatografía Líquida de Alta Presión , Humanos , Factor Intrinseco/sangre , Radioinmunoensayo , Técnica de Dilución de RadioisótoposAsunto(s)
Anemia Perniciosa/inmunología , Anticuerpos/análisis , Factor Intrinseco/sangre , Intercambio Materno-Fetal , Células Parietales Gástricas/inmunología , Complicaciones Hematológicas del Embarazo/inmunología , Adulto , Femenino , Humanos , Lactante , Recién Nacido , Embarazo , Vitamina B 12/uso terapéuticoRESUMEN
Recent evidence (Kolhouse et al., N. Engl. J. Med. 299: 785-792, 1978) demonstrates that commercial cobalamin (Vitamin B12) radioassay kits contain nonspecific R-protein binding agents that can give falsely normal results in patients who are actually cobalamin deficient. We tested three kits: with "purified" intrinsic factor as the binder, with intrinsic factor and the nonspecific R-protein sites blocked with "cobinamide," and non-purified intrinsic factor-R-protein binder. Results with use of the first two compared well with those by a microbiological assay (Lactobacillus leichmannii) and are in harmony with clinical impressions.
Asunto(s)
Proteínas Portadoras/sangre , Factor Intrinseco/sangre , Transcobalaminas/sangre , Bioensayo , Cobamidas , Humanos , Lactobacillus , Radioinmunoensayo , Juego de Reactivos para DiagnósticoRESUMEN
A patient with granulomatous gastritis is described. Two years after the presentation of his gastric disease he developed pernicious anemia. Lack of intrinsic factor production secondary to Crohn's disease of the stomach is felt to be the cause of his Vitamin B12 malabsorption.
Asunto(s)
Anemia Perniciosa/etiología , Gastritis/complicaciones , Adulto , Anemia Perniciosa/sangre , Enfermedad de Crohn/complicaciones , Gastritis/patología , Humanos , Factor Intrinseco/sangre , Masculino , Vitamina B 12/metabolismoRESUMEN
Since R protein binds cobalamin (vitamin B12) and cobalamin analogues, whereas intrinsic factor is highly specific for true cobalamin, we compared the serum cobalamin values obtained with these proteins in radioisotope dilution assays. With R protein, eight of 21 patients with cobalamin deficiency had serum cobalamin levels (mean, 204, range, 85 to 355 pg per milliliter) that overlapped with values for 74 normal subjects (mean, 576, range, 220 to 1230). With intrinsic factor, no patient values (mean, 36, range, less than 10 to 78 pg per milliliter) overlapped with the normal values (mean, 322, range, 130 to 785). Paper chromatography showed that these differences were due to the presence of cobalamin analogues. R protein constituted 51 to 85 per cent of the cobalamin-binding protein in 10 commercial serum cobalamin assay kits, which were said to contain "intrinsic factor". Human plasma contains cobalamin analogues that can mask cobalamin deficiency with current radioisotope dilution assays.
Asunto(s)
Técnica de Dilución de Radioisótopos/normas , Deficiencia de Vitamina B 12/diagnóstico , Vitamina B 12/análogos & derivados , Adulto , Cromatografía en Papel , Radioisótopos de Cobalto , Errores Diagnósticos , Femenino , Humanos , Factor Intrinseco/sangre , Masculino , Persona de Mediana Edad , Unión Proteica , Juego de Reactivos para Diagnóstico , Transcobalaminas/sangre , Vitamina B 12/sangre , Deficiencia de Vitamina B 12/sangreRESUMEN
Mucosal biopsies from multiple sites in the stomachs of 21 patients with pernicious anaemia have been examined. The histological changes almost always involved the entire gastric mucosa, including that of the pyloric antrum. Metaplastic changes were almost universal and consisted of intestinal metaplasia in the body and antrum and pyloric metaplasia in the body. The severity of the pyloric metaplasia was such as to make the distinction between body and antrum on biopsy impossible. No relationship was found between serum gastrin activity and the histological appearances of the gastric antrum or body.
Asunto(s)
Anemia Perniciosa/patología , Mucosa Gástrica/patología , Gastrinas/sangre , Adulto , Anciano , Anemia Perniciosa/sangre , Anemia Perniciosa/inmunología , Anticuerpos/análisis , Atrofia , Femenino , Gastritis/sangre , Gastritis/inmunología , Gastritis/patología , Humanos , Hiperplasia , Factor Intrinseco/sangre , Masculino , Metaplasia , Persona de Mediana Edad , Antro Pilórico/patologíaRESUMEN
Pernicious anemia is a rare disease of the pediatric age-group. Two kinds of pernicious anemia are known for this period, the "congenital" and the "iuvenile" form. Both are characterized by a megaloblastic anemia and a deficiency of the intrinsic-factor. The congenital form unusually begins before the second year of age and does not have changes of the mucous membranes of the stomach. The iuvenile form also called "adolescent or auto-immune pernicious anemia" has its beginning in the later childhood and shows like the adult form atrophy of the mucous membrane of the stomach, anacidity and antibodies against the intrinsic factor and parietalcells. A patient with congenital pernicious anemia is presented; the symptoms, diagnosis, differentialdiagnosis and therapy of this disease is reviewed.