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Query: UMLS:C0024523 (malabsorption)
 7,319 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

To evaluate the feasibility of gastroscopic screening for gastric malignancy in patients with pernicious anemia, all individuals treated with vitamin B12 in a well-defined population were identified. Individuals treated for an uncertain diagnosis were submitted to supplementary examinations. Of all individuals treated with vitamin B12 41% had unequivocal pernicious anemia, 13% possible pernicious anemia, 26% vitamin B12 malabsorption other than pernicious anemia, and 20% no verified vitamin B12 deficiency. The maximum crude prevalence of pernicious anemia was 1.98 per mile and the crude maximum incidence 16.7 x 10(-5) x year-1. The estimated annual cost of endoscopic gastric screening at 3-year intervals in patients with pernicious anemia younger than 75 years of age would be SEK 15,000/100,000 inhabitants, a cost that to a great extent could be financed by a more adequate prescription of vitamin B12 treatment.
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PMID:Prevalence and incidence of pernicious anemia. An evaluation for gastric screening. 671 30

Patients with jejunal diverticula usually are asymptomatic unless bacterial overgrowth within the diverticula is sufficient to cause vitamin B12 deficiency, by direct uptake of the vitamin by the bacteria, or malabsorption resulting from bacterial deconjugation of bile salts and impaired lipid digestion. The administration of broad-spectrum antibiotics usually constitutes effective treatment that suppresses bacterial flora, with surgery reserved for complications such as hemorrhage, perforation, and abscess formation, and acute or chronic intestinal obstruction. Our patient had many diverticula, and two courses of antibiotics failed to provide prolonged relief of symptoms. After surgical exploration to exclude the presence of partial intestinal obstruction or infiltrating disease of the terminal ileum, the segment of jejunum bearing diverticula was resected. Since operation the patient has remained asymptomatic, which suggests that in certain patients, even with many diverticula, surgical exploration and excision of the diverticula may be curative.
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PMID:Malabsorption in jejunal diverticulosis treated with resection of the diverticula. 677 18

The causes of megaloblastic anemia were studied in a survey of patients admitted to six Israeli hospitals over a period of 15 yr. Among the 203 patients identified, 69% had pernicious anemia, 12% had gastrointestinal disease, 9% had primary nutritional deficiency of whom only 1% were associated with pregnancy, and 7% had selective vitamin B12 malabsorption with albuminuria. Comparison with previously published surveys showed, that in contrast with earlier studies where primary nutritional deficiency was the cause of megaloblastic anemia in about 70% of cases and pernicious anemia in only 20%, in more recent studies the proportion of cases with primary nutritional anemia in general and those associated with pregnancy in particular was much lower. This is most probably the result of improved standards of living and a national program of preventive folate supplementation at maternity clinics. A potential hazard of such preventive programs is the aggravation of neurological complications in patients with undiagnosed vitamin B12 deficiency. Early recognition of pernicious anemia and other forms of selective B12 malabsorption is a new challenge created by the changing pattern of megaloblastic anemias.
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PMID:The changing pattern of megaloblastic anemia: megaloblastic anemia in Israel. 684 25

The absorption of vitamin B12, labelled with radioactive 58Co, was measured in 19 patients with cystic fibrosis and one child with the Shwachman-Diamond syndrome using the whole body counting technique. We found vitamin B12 absorption reduced to 7.97 on average, compared to 59.2% for the control group. The low vitamin B12 absorption correlated well with the reduced fat retention coefficients. After adding 0.212 pancreatin to the radioactive vitamin B12 test dose, the absorption quotas improved in all cases, the average being 61%. A meal poor in vitamin B12 tended to increase the absorption of the radioactive test dose to 23% on average. As yet there is no satisfactory explanation for the effect of the diet on the absorption of vitamin B12 in exocrine pancreatic insufficiency. This could be the reason why the malabsorption of vitamin B12 in patients with EPI can go unnoticed for many years and could possibly explain why vitamin B12 malabsorption in exocrine pancreatic insufficiency does not cause symptoms and signs of vitamin B12 deficiency for many years.
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PMID:Vitamin B12 absorption and exocrine pancreatic insufficiency in childhood. 721 91

A retrospective study was undertaken to audit physician's management of patients with a low serum level of vitamin B12 who were admitted to a university-affiliated teaching hospital during 1 year. Among the 34 patients 13 were proved to have pernicious anemia or vitamin B12 malabsorption, but for 12 of them there were unnecessary delays (several days or weeks) before initiation of investigation and therapy. An additional six patients, who had low serum levels of vitamin B12 and macrocytosis, most likely had true vitamin B12 deficiency, but proper investigation was not done and they did not receive any vitamin B12 or folic acid therapy. In another nine cases unexplained low serum levels of vitamin B12 were not properly investigated, and the patients either did not receive any vitamin B12 therapy or received it without proper documentation of a deficiency. Suggestions for facilitating early detection, investigation and treatment of megaloblastic anemia or vitamin B12 deficiency are given.
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PMID:Physician's management of suspected vitamin B12 deficiency. 745 53

Vitamin B12 metabolism and requirements during pregnancy and lactation are reviewed. Pregnant women who have been strict vegetarians for only a few years, and even those who consume low amounts of animal products, are more likely to become vitamin B12 deficient during pregnancy and lactation, to give birth to an infant who develops clinical or biochemical signs of B12 deficiency, and/or to have low levels of this vitamin in their breast milk. Populations that consume large amounts of animal products ingest 3-32 mcg/day, compared to 0-0.25 mcg/day for strict vegetarians. Changes in B12 metabolism during pregnancy affect intestinal absorption, changes in plasma concentrations, and placental transport. The recommended dietary allowance (RDA) during pregnancy is an increase from 2.0 mcg/day to 2.2 mcg/day to cover fetal storage. The World Health Organization (WHO) advises an increase of 0.4 mcg/day to a total of 1.4 mcg/day. Vitamin B12 metabolism during lactation involves the mechanism of secretion and forms in milk. For lactating women the WHO recommends that intake be increased by 0.3 mcg/day to a total of 1.3 mcg/day, while the RDA is increased from 2.0 to 2.6 mcg/day. There is some evidence that the infant's urinary methylmalonic acid excretion is reduced by intakes slightly higher than the current RDA, therefore the adequacy of the current RDA for vitamin B12 during infancy should be verified. More information is needed concerning the roles of the different transcobalamins during pregnancy and lactation, including their impact on placental and mammary transfer of cobalamin and their effect on intestinal absorption in the infant. Knowledge is also needed about the relative importance of maternal stores and current dietary intake on fetal storage of the vitamin, and on its concentration in breast milk. It is possible that vitamin B12 deficiency is more common in pregnant and lactating women and their young children in developing countries than has been recognized previously, primarily because of malabsorption.
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PMID:Vitamin B12 metabolism and status during pregnancy, lactation and infancy. 783 46

The high incidence of megaloblastic anemia observed at our institution (2.1% of hospital admissions) prompted us to analyze the causes of cobalamin and/or folate deficiency in 30 patients admitted during the period 1983-1991 to the Medical Department of Locarno District Hospital. The study population includes 19 women and 11 men with a mean age of 69 years (range 28-91 years). All patients had severe macrocytic anemia (mean hemoglobin 74 +/- 23 g/l, MCV 121 +/- 12 fl), striking megaloblastic changes in aspirated marrow, and an elevated serum level of LDH (2170 +/- 2150 U/l). 19 patients had associated thrombocytopenia, 12 leukopenia and 11 both thrombocytopenia and leukopenia. Treatment led to prompt reticulocytosis and correction of megaloblastic changes in all patients, as well as to nearly complete resolution of the neurologic disorder in a patient with severe spastic ataxia. In 15 patients, megaloblastic anemia was caused by folate deficiency related to alcoholism (n = 6, mean age 55 years) and old age or poverty (n = 9, mean age 73 years). Cobalamin deficiency was present in 9 patients (mean age 69 years); it was due to pernicious anemia in 6 patients and to malabsorption in 2, while the cause remained unexplained in 1. The last patients (mean age 76 years) had deficiency of both cobalamin and folate, related to alcoholism (n = 3) or poverty (n = 3).
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PMID:[Megaloblastic anemia: 30 cases in a district hospital]. 787 99

Deficiency of vitamin B12 is commonly reported in HIV-infected patients. We measured vitamin B12 levels in 36 HIV-infected patients with chronic diarrhea (> 3 stools/day for six weeks or more). Eight patients had an identifiable cause of diarrhea. Vitamin B12 levels were low in 39%. Sixteen of these patients were selected to undergo further testing, eight patients with low levels of vitamin B12 and eight with normal B12 levels. These 16 patients had both a stage II Schilling test and measurement of multiple serum D-xylose concentrations performed after both oral and intravenous doses of D-xylose. Integrated areas under the curves (AUC) for D-xylose concentration versus time were calculated for intravenous and oral doses, and D-xylose bioavailability was determined. Stage II Schilling tests were abnormal in 11 patients, (69%). D-Xylose bioavailability correlated closely with vitamin B12 absorption (r = 0.648, P < 0.01). Comparisons of mean values for CD4 count, serum albumin, Karnovsky score, six-month weight loss, 1-hr serum D-xylose levels and MCV failed to reveal a significant difference between those with and without abnormal serum vitamin B12 levels. These data indicate that below-normal levels of vitamin B12 are highly prevalent in HIV-infected patients with chronic diarrhea. Malabsorption of vitamin B12 occurs in the setting of an enteropathic process effecting both the proximal and distal small bowel. Since no risk factors for vitamin B12 deficiency could be identified, screening for vitamin B12 deficiency in HIV-infected patients with chronic diarrhea is strongly recommended.
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PMID:Malabsorption and deficiency of vitamin B12 in HIV-infected patients with chronic diarrhea. 792 36

Two brothers in a Chinese family with selective malabsorption of vitamin B12 associated with proteinuria (Imerslund-Grasbeck syndrome) presented with widespread mottled skin pigmentation, termed poikiloderma. In contrast to anaemia, this pigmentary disturbance remained unresponsive to vitamin B12 replacement. This is different from the reported hyperpigmentation sometimes seen in vitamin B12 deficiency which is reversible following treatment. As far as is known, an irreversible and persistent skin disorder has not been reported in this syndrome before.
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PMID:Imerslund-Grasbeck syndrome in a Chinese family with distinct skin lesions refractory to vitamin B12. 796 12

The clinical course is described of a 69-year-old patient with a malabsorption syndrome since her stay in Indonesia. Besides chronic diarrhoea and weight loss she suffered from malnutrition and had partial villous atrophy. Coeliac disease was considered in the differential diagnosis but considering the endemic appearance of postinfectious tropical sprue (PTS) in Indonesia and the extreme vitamin B12 deficiency our patient experienced, PTS appeared more likely. A good response to the therapy prescribed for PTS confirmed the diagnosis.
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PMID:[Postinfectious tropical malabsorption and the differences from non-tropical sprue (celiac disease)]. 813 27


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