[Pernicious anemia and other megaloblastic anemias]

OBJECTIVE

To describe the clinical and biological characteristics of a series of patients with megaloblastic anemia (MA) and to identify potential differences between patients with pernicious anemia (PA(+)) and patients with other MA (PA(-)).

METHOD

Retrospective study of 50 patients with MA diagnosed in our service between 1993 and 1998.

RESULTS

MA was diagnosed in 50 patients. The median age in the moment of diagnosis was 70.7 years. The causes of MA were: cobalamin deficiency (CD) in 40 cases (80%), folate deficiency (FD) in 7 cases (14%) and both deficiencies in 3 cases (6%). PA was diagnosed in 19 patients (38%). All cases showed hyper-segmented neutrophils and 41 cases (81%) macroovalocytosis. Hemoglobin level < 8 g/dl was present in 22 patients (44%). The median serum LDH level was 2.059 +/- 1.739 U/l. There was a lower frequency of female sex and a higher RDW in the group PA(+). There were no significant differences between both groups in the rest of studied features, except for the presence of antiparietal cell antibodies and anti-intrinsic factor antibodies in the group PA(+).

CONCLUSIONS

CD was the most frequent cause of MA in our series. PA was the most frequent cause of CD. Most cases of MA corresponded to a severe macrocytic anemia with hyper-segmented neutrophils, macroovalocytosis and very high serum LDH level. We did not identify any clinical or biological characteristic, except for the presence of antiparietal cell antibodies and anti-intrinsic factor antibodies and a higher RDW in the group PA(+), to permit distinguish the groups PA(+) and PA(-).

A diagnostic advice system based on pathophysiological models of diseases

Medical decision-support systems in which uncertainty plays an essential role are increasingly based on the formalism of probabilistic networks. Although this formalism is very powerful, the construction of actual networks is not straightforward, and requires the availability of clearly structured medical domain models as a starting point. In this paper it is argued that medical pathophysiological knowledge constitutes a good start for the development of such models, even though pathophysiological knowledge is semantically different from probabilistic knowledge. Two models concerning anaemia, which are part of a broad system covering the domain of anaemia, are discussed to illustrate the general approach.

Idiopathic non-obstructive hypertrophic cardiomyopathy, vitamin B12 deficiency and gastric adenocarcinoma: an unreported association in a teenager

A 14-year-old boy presented with anorexia and weakness whereon the diagnosis of dimorphic anaemia was made. An excellent response to iron and vitamin B12 was observed. In addition, the patient had non-obstructive hypertrophic cardiomyopathy. At endoscopy 2.5 years later, an adenocarcinoma was diagnosed and the patient underwent a high subtotal gastrectomy. To the best of our knowledge, this rare association has never been reported in children.

CONCLUSION

We report a youngster with pernicious anaemia, associated with nonobstructive hypertrophic cardiomyopathy in whom gastric adenocarcinoma was found. Patients with pernicious anaemia are at greater risk of developing gastric carcinoma than the general population, therefore we recommend routine periodic gastroscopic surveillance in the paediatric population with pernicious anaemia.

Oral cobalamin for pernicious anemia: back from the verge of extinction

BACKGROUND

High dose oral cobalamin therapy was shown to be effective for pernicious anemia and other cobalamin deficiency states 30 years ago, and physicians and patients state that they would find oral therapy useful, but a survey conducted in 1989 found that physicians were generally unaware of it.

OBJECTIVE

To assess physician awareness and use of oral cobalamin since 1989.

DESIGN, SETTING, AND PARTICIPANTS

Minneapolis area internists not listed as having subspecialties or academic business addresses were surveyed in 1989 and in 1996.

MEASUREMENTS AND RESULTS

There were 245 responses to the 1989 survey and 223 responses to the 1996 survey for response rates of 68% and 69%, respectively. The percentage of internists who ever used oral cobalamin to treat pernicious anemia increased from 0 in 1989 to 19% in 1996 (P < .001). The percentage who were aware of an effective oral cobalamin preparation for treating cobalamin deficiency states also increased significantly from 4 to 29% (P < .001). The percentage of internists who agreed with the incorrect view that sufficient quantities of cobalamin cannot be absorbed when given orally declined from 91% in 1989 to 71% in 1996 (P < .001).

CONCLUSION

Minneapolis internists' awareness and use of oral cobalamin treatment for pernicious anemia increased substantially between 1989 and 1996, but the majority of internists remained unaware of this treatment option.

[Polyneuropathy caused by vitamin B12 deficiency secondary to chronic atrophic gastritis and giardiasis]

INTRODUCTION

In chronic atrophic gastritis atrophy of the stomach glands leads to intrinsic factor deficit, with consequent failure to absorb vitamin B12 and gastric achylia, which predisposes to Giardia infection which in itself leads to depletion of vitamin B12. We describe the case of a patient with peripheral and central nervous system pathology due to lack of vitamin B12 secondary to the combined effect of these two disorders.

CLINICAL CASE

A 54 year old woman consulted us for paraesthesia and weakness of the legs which had been progressive for the previous two years. She presented with tactile hypoaesthesia, hypoparaesthesia, distal hyperreflexia and dysymmetry of the legs, ataxic-spastic gait and a positive Romberg sign. The investigations carried out showed the serum vitamin B12 level to be 3 pg/ml (N: 180-900), hemoglobin 13 g/dl and MCV 111 fl with MCHC 348/dl; neurophysiological studies: compatible with demyelinating motor polyneuropathy. Schilling test: deficit of absorption of vitamin B12 which was corrected on administration of intrinsic factor; gastroscopy; atrophic gastritis which confirmed the morbid anatomy findings. There was also flora containing Helicobacter and massive Giardia infection. Replacement and antibiotic therapy was followed by complete remission of the clinical picture.

CONCLUSION

We emphasize the excellent clinical response to treatment in spite of the time elapsed since onset of symptoms.

[Late manifestation of common variable immunodeficiency by Biermer's disease]

BACKGROUND

Common variable immunodeficiency (CVI) is a heterogeneous disorder characterized by decreased production of antibodies. Clinical presentation of CVI is generally that of recurrent pyogenic infections. Autoimmune diseases can also occur. The age of onset of symptoms shows two peaks at 1-5 and 16-20 years.

CASE REPORT

A 77-year-old man was admitted in hospital for pernicious anemia. We discovered hypogammaglobulinemia with low levels of immunoglobulin G, A and M, but normal T-cell levels. We diagnosed common variable immunodeficiency. This patient had not had recurrent pyogenic infections.

DISCUSSION

This case shows that common variable immunodeficiency can be revealed late by an autoimmune disease. The pathogenesis of autoimmune diseases in this immunodeficiency remains unknown despite several possible explanations.

[A Chinese patient with pernicious anemia; a medical experience from the Indonesian period]

On May 19th 1952 a 64-year-old Chinese man was admitted to a hospital at Yogyakarta (Indonesia) on account of a sawing noise in both ears and some soreness of the tongue. He had macrocytic anemia (haemoglobin: 3.7 mmol/l) and the tongue showed some smooth patches. A presumptive diagnosis of pernicious anaemia was confirmed by gastric analysis which revealed a histamine fast achlorhydria. On treatment with vitamin B12 the noise in the ears rapidly disappeared and there was a characteristic rise in reticulocytes and haemoglobin content. After 3 years the patient died of inoperable gastric carcinoma. There probably was a hereditary component as in a 54-year-old cousin, who also suffered (and died) from gastric carcinoma, gastric analysis showed a histamine fast achlorhydria. The patient is the first case of pernicious anaemia described in a Chinese resident of Indonesia. A survey of the literature revealed that until now pernicious anaemia has been recorded in 31 Chinese patients, in chronological order from the following countries: U.S (1945), Indonesia (1954), Singapore (1967), Hong-Kong (1969) and China (1990). In the autochthonous Chinese population no case has yet been reported.

Fortification of the food supply with folic acid to prevent neural tube defects is not yet warranted

The relationship between adequate folate intake by pregnant women and reduced risk of delivering infants with neural tube defects (NTDs) has raised the public health issue of increasing folate intake among women of reproductive age. The U.S. Food and Drug Administration has proposed fortifying cereal and grain products with folate, although at a level less than half that recommended by its sister agency, the Centers for Disease Control and Prevention. We question the wisdom of fortifying foods with folate at this time, given a variety of uncertainties, which include the following: 1) the fact that neural tube defects seem to be a multifactorial group of disorders that are polygenic as well, so folate will not help in all or perhaps even in most cases; 2) the incidence of NTDs, which varies geographically, has been decreasing in the United States for years; 3) fortifying more food with folate may pose safety concerns for some not as risk for NTDs; 4) no dose-response relationship has been established between folate and NTDs; and 5) fortification in this case would represent a conceptually new intervention strategy for addressing what may be a metabolic abnormality where pharmacological doses of a nutrient may be required. Launching a major nutritional intervention before better understanding the relationship between nutrients and NTDs and without reasonable assurance that it will not shift health risks from one group (developing embryos) to another (primarily adults with pernicious anemia) might prove ineffective and/or harmful.

[Addison-Biermer disease combined with chronic posthemorrhagic iron-deficiency anemia (dimorphic anemias)]

The paper reports 7 cases of dimorphic anemia, development of Addison-Biermer disease in preexisting chronic posthemorrhagic anemia. The authors consider some diagnostic and therapeutic aspects. It is thought valid to discontinue iron preparations prior to vitamin B12 therapy and to start them again upon the arising reticulocytic crisis.

Cobalamin

Cobalamin (vitamin B12) is an essential nutrient derived exclusively from bacterial sources. It is an essential cofactor for three known enzymatic reactions. Untreated deficiency, caused by either the autoimmune disease pernicious anemia or nutritional lack, results in a macrocytic anemia and/or subacute combined degeneration of the spinal cord and is eventually fatal. Cobalamin in serum is bound to two proteins, transcobalamin and haptocorrin. The former is responsible for the essential delivery of cobalamin to most tissues. Inadequate tissue availability of cobalamin results in increased concentration of methylmalonic acid and homocyst(e)ine due to inhibition of methylmalonyl-CoA mutase and methionine synthase, respectively. Strict vegetarians have long been known to be at risk of cobalamin deficiency, which develops insidiously over many years. It is now clear that a significant number of the elderly and HIV-positive individuals are also at increased risk of deficiency. Any individual with reduced ability to split cobalamin from food-protein may also become deficient even though intrinsic factor is present. Diagnosis of cobalamin deficiency has frequently relied on total serum cobalamin and the Schilling test. Newer approaches such as analysis of methylmalonic acid, homocyst(e)ine, holotranscobalamin, anti-intrinsic factor antibodies, and serum gastrin may provide more cost-effective testing, as well as identify those with a covert deficiency.

[A case of rheumatoid arthritis associated with pernicious anemia and bronchiolitis obliterans organizing pneumonia]

A case of rheumateid arthritis (RA) with pernicious anemia (PA) and wandering multiple patchy densities in bilateral lung fields is reported. A 72-year-old woman was hospitalized in February 1994, because of cough. She had already advanced RA (Class IV, Stage IV). She showed macrocytic and hyperchromic anemia as follows ; red-cell count (RBC), 176 x 10(4)/microliters; hemoglobin (Hb),7.2 g/dl; hematocrit (Ht), 21.0% ; MCV, 119.3 fl; and MCH, 40.9 pg. Chest roentgenogram revealed multiple patchy densities in bilateral lung fields and there was no response to the administration of antibiotic agents. From these clinical pictures bronchiolitis obliterans organizing pneumonia (BOOP) was highly suspected. After steroid injection into the joint space, the abnormal lung shadows disappeared. Anemia had been recovering spontaneously, but recurred in July. The results of blood examination were as follows ; RBC, 162 x 10(4)/microliters; Hb, 6.7ng/dl; Ht, 19.1%; MCV, 117.9 fl; and MCH, 41.4 pg. Anti-intrinsic factor antibody was positive. The level of serum vitamin B12 was low, 76 pg/ml. Sternal bone marrow aspiration showed magaloblastic changes with hypersegmentation of granulocytes. PA was diagnosed and improvement was noted after the intramuscular administration of vitamin B12. Subjective symptoms based on RA did not change during the clinical course. It is suggested that the pathogenesis about the combination of RA, BOOP and PA is related to common immunological abnormalities in our patient. A case of RA with PA and BOOP has not been reported previously, thus this case is considered clinically valuable.

Bioassay of gastrin using the isolated vascularly perfused rat stomach. A new, simplified and sensitive method

Radioimmunoassays are sensitive and specific methods for measurement of the concentrations of regulatory peptides. However, aspects of physiological, pathophysiological and pharmacological research require knowledge about the biological activity which does not necessarily vary concomitantly with immunological activity. The present work describes a simplified bioassay for gastrin based on the gastric histamine releasing properties of this peptide, using an isolated vascularly perfused rat stomach preparation with a crystalline perfusate and a specific radioimmunoassay for histamine. The establishment of a dose-response curve is described, as well as the utilization of the bioassay on sera from patients with hypergastrinaemia. The method is sensitive for gastrin in the low (4 pmol L-1) picomolar range.

Vitamin B12 deficiency: underdiagnosed, overtreated?

Neurologic damage may become permanent when the disorder is mistaken for multiple sclerosis or diabetic neuropathy--hence the need for prompt parenteral B12 in patients with pernicious anemia. The need for B12 injections is questionable for patients with achlorhydria and for those with a marginal or low serum B12 level but no signs or symptoms of deficiency.