Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0021051 (immunodeficiency)
 71,517 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Described here is a patient with severe watery diarrhea associated with common variable immunodeficiency. Malabsorption for fat, bile acids, vitamin B12 and xylose was demonstrated, but the patient failed to respond to all the usual therapeutic maneuvers. The diarrhea responded only to high dose steroid therapy. Intestinal perfusion studies showed a hitherto undescribed, presumably acquired, glucose-stimulated water, sodium and chloride secretion in the jejunum and ileum, whereas normal fluid and electrolyte transport occurred from bicarbonate and mannitol solutions. Glucose absorption itself was normal and no hormonal, morphologic or biochemical defect was demonstrated to account for the phenomenon. The patient was also interesting when compared with other patients with common variable immunodeficiency in having normal plasma cells in the intestinal mucosa and an extensive family involvement.
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PMID:Immunodeficiency, malabsorption and secretory diarrhea. A new syndrome. 47 4

The diagnoses which may be arrived at by examination of peroral small bowel mucosal biopsy specimens are presented. Celiac sprue, unclassified sprue (refractory sprue), infectious gastroenterititis, stasis syndrome and kwashiorkor have a severe mucosal lesion. Other clinical conditions are required to establish the diagnosis in these diseases. A number of diseases have specific diagnostic features. Included are Whipple's disease, abetalipoproteinemia, collagenous sprue, primary intestinal lymphoma, eosinophilic gastroenteritis, giardiasis, coccidiosis, strongyloidiasis, lymphangiectasis and the intestinal immunodeficiency diseases. Mucosal abnormalities may be present in other diseases but the diagnoses are usually made on other criteria than small bowel biopsy. These include vitamin B12 or folic acid deficiency, Crohn's disease, gastrinoma, acrodermatitis enteropathica, amyloidosis, chronic granulomatous disease, lipid storage diseases, histoplasmosis, capillariasis, cytomegalovirus infection, schistosomiasis and macroglobulinemia.
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PMID:Histologic diagnosis of diseases of malabsorption. 51 56

Transcobalamin II (TC II) is a serum protein responsible for transporting vitamin B12 to the cells. A previous observation of a child with congenital TC II deficiency and agammaglobulinemia suggested that this protein plays an important role in the immune response. Accordingly, TC II levels ere determined in 32 patients with autoimmune disease (AID) (i.e. 26 with lupus erythematosus, 4 with dermatomyositis, and 2 with autoimmune hemolytic anemia) and in 40 patients with acquired immunodeficiency due to chemotherapy. It was found that elevated TC II levels corresponded to active phases of AID. Changes in TC II levels correlated better with the clinical course of AID than complement, antinuclear antibody or native DNA binding capacity. This suggests that TC II could be a valuable parameter in following up activity of AID.
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PMID:[Increase of unsaturated transcobalamine II in autoimmune diseases; effect of immunosuppressive therapy (proceedings)]. 69 99

HLA typing was performed on 384 individuals of an isolated population of 1,500 people with a familial aggregate of lymphoma and immunodeficiency cases. Eighty-five % of the total population were descendants of the founding couple. First cousin marriages were common. There was a three-fold or higher increase of the following haplotypes as compared to the frequencies in Sheffield: HLA-A28,Bw35, HLA-A28, B18, HLA-A10, B18, HLA-A2, B18,HLA-A11, Bw40 and HLA-A11, B7. The frequency of HLA-A1, B8 was low (5.4%). The most common genotype was HLA-A2, B12/A2, B12 followed by HLA-A2, B12/A28, Bw35. We found 20 HLA homozygous individuals, of these 15 were HLA-A2, b12/a2, b12. There were two possible HLA cross-overs which may be confirmed and three postulated cross-overs which can never be confirmed as one or both parents of the individuals in question are deceased. Some of the haplotypes could be traced back to the first, second and third generations, i.e. to the first half of the nineteenth century. No single haplotype or antigen was shared by the patients.
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PMID:HLA haplotypes in a genetic isolate in Newfoundland. A population showing 8% homozygosity and a familial aggregate of lymphoma and immunodeficiency cases. 97 11

AIDS-associated gastric secretory failure has been characterized by decreased secretion of acid, pepsin, and gastric juice volume. To determine whether decreased intrinsic factor secretion and vitamin B12 malabsorption occur in this entity, we performed prospective measurements of maximal acid output, intrinsic factor output, vitamin B12 absorption, serum vitamin B12, and holotranscobalamin II in 10 consecutive AIDS patients. Four of 10 patients had low maximal acid output, i.e., < or = 1.5 mEq/h (control = 12.8 +/- 9.0, range 2.5-25 mEq/h). Four patients had low intrinsic factor output, i.e., < or = 1.1 microgram/h (control = 8.2 +/- 6.9, range 3.1-19.4 micrograms/h). One patient with low intrinsic factor output had low serum vitamin B12 and a Schilling test consistent with pernicious anemia. A second patient with very low intrinsic factor output (0.16 micrograms/h) had low parts I and II Schilling tests; malabsorption most likely resulted from both low intrinsic factor secretion and ileal disease. One of three vitamin B12 malabsorbing patients, with normal serum vitamin B12, had low holotranscobalamin II, 25 pg/ml (control holotranscobalamin II = 76 +/- 44, range 44-152 pg/ml). Maximal acid output and intrinsic factor output did not correlate in AIDS (r = 0.36, p = 0.30) in contrast to the expected correlation in controls (r = 0.91, p = 0.03). We conclude that low intrinsic factor secretion is common in AIDS and contributes to vitamin B12 malabsorption. Decreased parietal cell secretion of intrinsic factor and acid may occur independently in human immunodeficiency virus-associated gastric secretory failure. Low holotranscobalamin II, an early manifestation of vitamin B12 malabsorption, results in decreased delivery to vitamin B12-dependent tissues prior to depletion of serum vitamin B12. Regular supplementation with vitamin B12 may therefore be warranted in patients with advanced HIV infection.
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PMID:Decreased intrinsic factor secretion in AIDS: relation to parietal cell acid secretory capacity and vitamin B12 malabsorption. 144 41

Three Chinese infants with methylmalonic acidaemia were described. They presented in the neonatal period with recurrent episodes of poor feeding, lethargy, apnoea and severe acidosis. The diagnosis was established by increased methylmalonic acid concentration in the plasma and/or urine. Pancytopenia was a prominent feature in all three patients. Only patient three had assessment of lymphocyte subsets and it showed diminished population of B-lymphocytes and a reversed CD4/CD8 ratio. All three patients were unresponsive to vitamin B12. They experienced severe infections including Gram-negative septicaemia, candidiasis and Pneumocystis carinii pneumonia which caused their deaths. Patients with this disease should be regarded as having severe immunodeficiency, and in addition to optimal metabolic control, they should be treated aggressively for any suspected infective episodes.
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PMID:Immunodeficiency in methylmalonic acidaemia. 156 72

Studies of cognitive function in subjects with human immunodeficiency virus type 1 (HIV-1) infection who remain relatively asymptomatic (ie, Centers for Disease Control stages II and III) have provided widely variable estimates of cognitive impairment. In view of the finding that approximately 25% of asymptomatic HIV-1-infected subjects demonstrate either marginal or overt vitamin B12 deficiency, we have investigated plasma vitamin B12 status as a potential cofactor in studies of HIV-1-related cognitive impairment. When cognition was assessed in asymptomatic (Centers for Disease Control stages II and III) HIV-1-infected participants taking into consideration vitamin B12 status, those subjects with low plasma vitamin B12 levels (less than 180 pmol/L) performed more poorly than did those with normal (greater than or equal to 180 pmol/L) vitamin B12 status on specific measures of information processing speed and visuospatial problem-solving skills. These findings suggest that concurrent vitamin B12 deficiency may be a cofactor in subtle cognitive changes observed in the asymptomatic stages of HIV-1 infection. These differences in prevalence of low plasma vitamin B12 levels may help to explain differences among studies in the proportion of HIV-1-infected subjects showing cognitive impairment.
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PMID:Plasma vitamin B12 level as a potential cofactor in studies of human immunodeficiency virus type 1-related cognitive changes. 850 91

The myelopathy associated with human immunodeficiency virus (HIV) infection closely resembles that in subacute combined degeneration, a disorder of vitamin B12 metabolism. To investigate whether the disorders share a pathogenetic mechanism, S-adenosylmethionine (SAM) and S-adenosylhomocysteine (SAH) were measured in the cerebrospinal fluid (CSF) of 20 HIV-seropositive patients and 30 HIV-negative patients who were undergoing lumbar puncture for other medical reasons. The HIV-seropositive patients had significantly lower CSF concentrations of SAM (mean 77 [SD 25] vs 131 [35] nmol/l; p less than 0.001) and significantly higher concentrations of SAH (30.5 [6.8] vs 19.0 [7.1] nmol/l; p less than 0.001) than the controls. There was therefore a significant difference between the groups in the SAM/SAH (methylation) ratio (HIV 2.7 [1.0] vs control 7.6 [3.4]; p less than 0.001). There were no correlations between SAM or SAH concentrations or methylation ratio and age or sex in both groups, or serum B12 and folate concentrations, CSF folate, serum or CSF methylmalonic acid, risk factors, body mass index, specific drug treatment received, or disease stage in the HIV group. This finding suggests that HIV affects the brain from a very early stage of the infection. We suggest that, as in the pig, the CSF methylation ratio closely reflects that in the brain. In HIV-infected patients a reduced brain methylation ratio would inhibit methyltransferase enzymes, which would lead to hypomethylation in the central nervous system and ultimately to neurological lesions. In a pig model of subacute combined degeneration and in vitamin-B12-deficient human beings, the primary cause of the low methylation ratio is impaired recycling of SAH back to SAM, a process which requires vitamin-B12-dependent methionine synthase. The HIV patients in this study were vitamin B12 and folate replete, which suggests a different cause for the low methylation ratio.
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PMID:Evidence of brain methyltransferase inhibition and early brain involvement in HIV-positive patients. 167 30

An increased prevalence of vitamin B12 deficiency has been reported in patients infected by the human immunodeficiency virus (HIV). We report an unexpectedly high prevalence (20%) of such abnormal vitamin B12 metabolism in a population of HIV-infected patients referred for neurological evaluation. This abnormality was associated with both peripheral neuropathy and myelopathy. A majority of those treated with cyanocobalamin had a therapeutic response. Selected neuropathological results suggest a relationship between vitamin B12 deficiency and vacuolar myelopathy. Vitamin B12 deficiency may be a frequent and treatable cause of neurological dysfunction in patients with HIV infection.
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PMID:Abnormal vitamin B12 metabolism in human immunodeficiency virus infection. Association with neurological dysfunction. 184 71

The possible mechanisms of neutropenia associated with both human immunodeficiency virus (HIV) infection and drug treatment in adults are examined, and the current and investigational strategies for managing neutropenia are reviewed. Neutropenia associated with HIV arises from diverse mechanisms, including cellular immune dysfunction, direct effects on progenitor cells, humoral immune dysfunction, and vitamin deficiencies. Drug-induced neutropenia may be related to direct cytotoxic effects, immunologic mediators, and the effects of vitamin depletion on the bone marrow. Bone marrow toxicity in patients receiving zidovudine appears to be more frequent in those patients with advanced disease, low CD4 cell counts, a pretreatment anemia, low serum vitamin B12 levels, and low or low normal serum folic acid levels. Patients with AIDS also are at increased risk for adverse events associated with folate antagonists and sulfonamides compared with other patient populations. Lithium therapy has improved neutrophil counts in patients receiving zidovudine; however, the toxicities associated with use of lithium, combined with the lower dosages of zidovudine now recommended, may obviate its use. The use of colony-stimulating factors appears promising for increasing the number and function of circulating neutrophils. Although concomitant use of interferon alfa and zidovudine may result in a strong synergistic anti-HIV effect, dose-limiting neutropenia has been reported in patients receiving the combination. There are currently no controlled data assessing the effectiveness of intravenous immune globulin in the treatment of HIV-related or drug-related neutropenia. In evaluating neutropenia, the clinician must attempt to discern whether the neutropenia is more likely related to disease state(s) or drug therapies. Potential management strategies include modulation of the disease state, discontinuation or dose reduction of the offending agent, or administration of exogenous immune enhancer.
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PMID:Neutropenia in patients infected with human immunodeficiency virus. 203 44


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