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)

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

We observed increased hemoglobin A2 (HbA2) levels in an asymptomatic human immunodeficiency virus-1 (HIV1) patient with no previous history of beta-thalassemia. He was treated only with zidovudine (AZT). In an attempt to understand this observation, a retrospective study was initiated to determine whether mean HbA2 levels are higher in AZT-treated patients than in subjects not receiving this drug and to assess if other hematologic alterations are associated with elevated HbA2. One hundred fifty-one HIV-positive cases were investigated; AZT was administered to 81 of them. The mean value of HbA2 was 0.032 (SD +/- 0.005) for the treated group vs. 0.027 (SD +/- 0.004) for the controls. This difference was highly significant (P < 0.001). Twenty-four patients (31%) in the treated group had elevated HbA2 levels vs. none in the controls. Bone marrow toxicity seemed to be more significant in patients with heightened HbA2 values, and HbA2 levels did not increase with CDC clinical stage. We conclude that AZT may be linked to high HbA2 levels in some patients.
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PMID:Increase of hemoglobin A2 in human immunodeficiency virus-1-infected patients treated with zidovudine. 834 56

Bone marrow toxicity is a dose-limiting side effect of chloroethylnitrosourea (CNU) chemotherapeutic alkylating agents. A major determinant of CNU cytotoxicity is the methylation of guanine at the O6-position and the subsequent formation of interstrand DNA cross-links. O6-Methylguanine DNA methyltransferase (MGMT) removes alkyl groups from the O6 position of guanine and has been shown to repair CNU-induced DNA damage. We have previously demonstrated that transplantation of murine bone marrow cells transduced with a recombinant retroviral vector expressing MGMT via the human phosphoglycerate kinase promoter (PGK-MGMT) protects animals in vivo from acute myelotoxicity associated with CNU treatment. In the present study, we examined the effects of 1,3-bis(2-chloroethyl)-1-nitrosourea (BCNU), a commonly used CNU, on long term recovery of the lymphoid compartment, including thymus reconstitution, peripheral T and B cell populations, and lymphocyte mitogen responses in mice reconstituted with PGK-MGMT-transduced hemopoietic cells. Mice transplanted with either mock-infected control or PGK-MGMT-transduced stem cells were treated with five weekly doses of BCNU. Analysis of the lymphoid compartment demonstrated significant damage 3 mo after the last BCNU dose in control animals. In contrast, the profound deficiency in CD4+CD8+ double-positive thymocytes and mature lymphocytes observed in control mice surviving BCNU treatment was completely reversed in mice transplanted with PGK-MGMT-transduced bone marrow and was associated with molecular evidence of in vivo selection of transduced cells in the lymphoid compartment. Thus, long term immunodeficiency following CNU therapy may be prevented by genetic modification of murine hemopoietic stem cells with MGMT, leading to significant improvement in post-transplant immune function.
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PMID:Reversal of 1,3-bis(2-chloroethyl)-1-nitrosourea-induced severe immunodeficiency by transduction of murine long-lived hemopoietic progenitor cells using O6-methylguanine DNA methyltransferase complementary DNA. 899 23