Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0027947 (neutropenia)
 17,527 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Bone marrow suppression is the major dose-limiting toxic effect of zidovudine (azidothymidine; AZT) in children with human immunodeficiency virus infection. We evaluated the effect of subcutaneously administered granulocyte colony-stimulating factor (G-CSF) in pediatric patients whose absolute neutrophil count was less than 0.8 x 10(9)/L during AZT therapy despite dosage reductions to 120 mg/m2 every 6 hours. Nineteen patients between 6 months and 20 years of age were treated with AZT and G-CSF and monitored for 2 to 12 months. All had previously shown improvement while receiving AZT but had required dosage reduction or discontinuation. By using a sliding dosing schedule of G-CSF, we attempted to maintain the absolute neutrophil count between 1.5 and 5.0 x 10(9)/L. Administration of G-CSF resulted in a significant increase in the median leukocyte count (2.0 x 10(9)/L to 4.14 x 10(9)/L; p = 0.004), and the median absolute neutrophil count (1.02 x 10(9)/L to 2.96 x 10(9)/L; p = 0.0006). G-CSF was well tolerated, but mild thrombocytopenia developed in nine children. Administration of G-CSF and AZT was discontinued in two patients because of continuing neutropenia. With doses of G-CSF ranging from 1 to 20 micrograms/kg per day, 17 of 19 patients were able to tolerate AZT at a dose of 120 to 180 mg/m2 every 6 hours. We conclude that G-CSF therapy enables patients who have had AZT-related neutropenia to receive therapeutic doses of AZT.
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PMID:Combination treatment with azidothymidine and granulocyte colony-stimulating factor in children with human immunodeficiency virus infection. 127 53

Zidovudine (formerly azidothymidine) is a potent inhibitor of the human immunodeficiency virus (HIV) reverse transcriptase and represents the first approved drug showing clinical efficacy in HIV-associated diseases. However, considerable toxicity causing macrocytic anemia, neutropenia, and myopathy has been reported, with severe mitochondrial alterations as a special feature of this myopathy. The mitochondrial changes are consistent with the fact that zidovudine acts as an inhibitor of the mitochondrial gamma-polymerase. Electron microscopically, we could confirm the presence of severely altered mitochondria in a 32-year-old male, who developed a necrotizing myopathy after daily administration of 1,000 mg zidovudine over a period of 15 months. In addition, there were even more severe nuclear changes that, for the most part, have not been documented electron microscopically in HIV-related myopathy either with or without zidovudine treatment, especially in non-necrotic and non-regenerating fibers. Since various in vitro studies have shown interference of zidovudine with nuclear DNA metabolism even in human cell lines, we assume that the nuclear changes that we observed are at least in part related to zidovudine treatment.
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PMID:Nuclear and mitochondrial changes of muscle fibers in AIDS after treatment with high doses of zidovudine. 128 95

The drug zidovudine (AZT), a synthetic thymidine analogue, has been used in the treatment of acquired immunodeficiency syndrome (AIDS). Clinical use of zidovudine has induced haematopoietic toxicity manifested by anaemia, neutropenia, frequent thrombocytopenia, and overall bone-marrow suppression. The monovalent cation lithium has been shown to be an effective agent capable of modulating several aspects of haematopoiesis such as the induction of neutrophilia, thrombopoiesis, and protection against suppression of haematopoietic progenitor stem cells following exposure to anticancer drugs and/or radiation in the treatment of malignant disease. We here report the results of studies designed to evaluate the effectiveness of lithium in reversing and/or protecting against either murine or human bone marrow derived haematopoietic progenitors, i.e. (CFU-GM, CFU-Meg, and BFU-E) when co-cultured in the presence of zidovudine in vitro. Lithium chloride (LiCl) reversed zidovudine toxicity to either murine or human derived CFU-GM and CFU-Meg that was optimal at a concentration of 1 mM (P less than 0.05). However, the addition of lithium failed to influence zidovudine toxicity toward either murine or human BFU-E. In summary, these results support the scant clinical studies that have described the presence of neutrophilia and/or thrombopoiesis in zidovudine-treated AIDS patients receiving lithium. In addition, these data further confirm the need for more detailed evaluation of lithium as an adjuvant agent to reduce the haematopoietic toxicity associated with the use of antiviral therapy in HIV-infected patients.
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PMID:Effective modulation of the haematopoietic toxicity associated with zidovudine exposure to murine and human haematopoietic progenitor stem cells in vitro with lithium chloride. 131 88

Granulocyte-macrophage colony-stimulating factor (GMCSF) is a hematopoietic protein that has been studied both in vitro and in vivo in human immunodeficiency virus (HIV) infection. Since both HIV infection primarily and zidovudine (formerly AZT) treatment secondarily may result in neutropenia, administration of GMCSF to persons with HIV infection is generating considerable interest. Despite in vitro studies demonstrating that the agent may stimulate HIV replication, in the presence of zidovudine a synergistic inhibition of replication occurs. Early clinical studies in patients with the acquired immunodeficiency syndrome indicate that GMCSF can raise neutrophil counts with or without concurrent zidovudine treatment. The long-term safety and tolerance of the combination has to be established.
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PMID:Granulocyte-macrophage colony-stimulating factor and zidovudine in the treatment of neutropenia and human immunodeficiency virus infection. 149 10

Zidovudine, a nucleoside analog, was the first agent proved to be effective in the management of human immunodeficiency virus type 1 (HIV-1) infection. After demonstration of zidovudine's in-vitro activity against HIV-1 in 1985, the drug was rapidly evaluated in phase I and phase II clinical trials and was found to be effective in decreasing both mortality and the incidence of opportunistic infections in patients with the acquired immunodeficiency syndrome (AIDS) and advanced AIDS-related complex; the drug was also found to have a substantial but tolerable toxicity profile. Since the licensure of zidovudine in 1987, an intensive clinical research effort has established the drug's efficacy in the prevention of disease progression in asymptomatic and mildly symptomatic HIV-infected persons and has established the success of lower-dose therapy in patients at all stages of disease. The current recommendation is to use zidovudine at a dose of 500 to 600 mg/d in both symptomatic and asymptomatic persons with CD4 counts of less than 500/mm3. The major toxicities of anemia and neutropenia are less frequent at the lower doses presently used and can be managed by dose reduction or by use of hematopoietic growth factors. The inexorable disease progression seen despite zidovudine therapy and the isolation of clinical strains of HIV-1 resistant to zidovudine in vitro highlight the limitations of prolonged monotherapy with this agent. Although alternative dideoxynucleoside agents (for example, didanosine [dideoxyinosine and zalcitabine dideoxycytidine]) are available for the management of HIV-infected persons, zidovudine remains the cornerstone of antiretroviral therapy. Current research efforts are directed at elucidating the clinical relevance of zidovudine resistance and studying regimens in which zidovudine is used in combination with other agents. This latter approach holds great promise for improving efficacy, limiting toxicity, and perhaps preventing the emergence of viral resistance. For the forseeable future, zidovudine will continue to play a role in the development and in our understanding of antiretroviral therapy.
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PMID:Zidovudine: five years later. 844 32

Thirty-five children diagnosed of AIDS were studied in order to evaluate toxicity and efficacy of oral Zidovudine treatment (AZT), as well as to analyze the clinical, biochemical, immunological and virological evolution of HIV infection throughout the treatment. Patients (19 males and 16 females) were studied from April 1988 to May 1990 with a mean follow-up time of 13.5 months (SD = 6.7 months). The mean age of the group was 4.68 years. The means of acquisition of this disease was 71.45 vertical and 28.6% via hemo-derivatives. Tolerance has been good with the main toxicity being hematological (28.5% anemia and/or neutropenia), 23% of which required blood supplements. The presence of neurological involvement and thrombopenia were observed in the incidence of greater toxicity. No influence on weight during AXT treatment was observed and hepatosplenomegalia and adenopathies were not modified. Bacterial and opportunistic infections were observed in 97.1% and 20% of patients, respectively. Neurological evolution was irregular and the improvement observed in some patients was mild and transitory. Three patients died during the follow-up from intercurrent infectious process. A progressive increase in MCV and a tendency towards leucopenia and lymphopenia (mainly in hemo-derivative infected patients) was observed. Neither significant immunological nor virological changes were observed during the treatment (except the tendency to diminish basal hypergammaglobulinemia). The results of this study were compared to other pediatric series treated with AZT.
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PMID:[Long-term follow-up study of 35 children with ADS treated with zidovudine (AZT)]. 157 12

Fifteen children (11 males and four females), on oral Zidovudine (AZT) for symptomatic HIV infection were studied retrospectively. Twelve acquired HIV via blood products, two from vertical transmission (maternal intravenous needle sharing) and one through breast feeding. Their mean age at the start of therapy was 8.6 years (s.d. 4.4 years, range 1.8-15.3 years). The main indications for therapy were failure to thrive (FTT) in 10, recurrent respiratory tract infections (RRTI) in eight, and developmental delay (DD) in one, with overlapping indications being Pneumocystis carinii pneumonia (PCP) in one and pulmonary lymphoid hyperplasia (PLH) in two. The mean commencement dose was 24 mg/kg per day orally in 3-6 divided doses (range 16-35 mg/kg per day). The duration of therapy was 2 weeks-2 1/2 years. Significant improvement in growth was observed by 2 months; at 6 months, growth was sustained in these otherwise ill children, with only two falling below pretreatment weight. Decrease in the frequency of RRTI based on subjective reports of the attending clinicians was observed in seven of the eight evaluable children still on therapy. Improvement in PCP and PLH occurred in two children and modest improvement was subjectively reported in PLH in one while still early in the course of therapy. Overall, AZT was well tolerated. Dose modifications were for neutropenia in three (of which only two were drug related), rapidly falling neutrophil count in one, anaemia in two (with concurrent history of chronic gastrointestinal tract blood loss in one), severe GIT irritation in one and transient sedation in one. Seven opportunistic infections were reported (three in the same patient) of which two occurred following cessation of therapy, one after only 2 weeks of therapy, and one had not been on primary prophylactic therapy. Three deaths occurred, one associated with opportunistic infections and two while off therapy (one respiratory failure, one PCP).
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PMID:Zidovudine (AZT) therapy in children with HIV infection: the Australian experience. 170 96

The efficacy of recombinant human granulocyte colony-stimulating factor (rhG-CSF) on neutropenia was evaluated in 14 patients with AIDS and AIDS-related complex (ARC). In all patients, including 11 neutropenic patients, 100 or 200 micrograms/m2 of rhG-CSF significantly increased the neutrophil counts. The response was greater in patients with higher neutrophil counts before the treatment, and was also dose-dependent. Although the effect seemed to be less potent, the agent also increased the neutrophil counts even when zidovudine (azidothymidine, AZT) and other myelosuppressive antiviral agents were administered simultaneously. These observations indicate that rhG-CSF may be beneficial in preventing and treating some secondary infections, and will make it easier to continue therapy with antiviral agents in patients with AIDS or ARC.
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PMID:Efficacy of recombinant human granulocyte colony-stimulating factor on neutropenia in patients with AIDS. 170 65

To evaluate the effect of recombinant granulocyte-macrophage colony-stimulating factor (GM-CSF) on patients with acquired immunodeficiency syndrome (AIDS) or AIDS-related complex (ARC) who were intolerant to zidovudine because of neutropenia, we performed a randomized, open-label study in which patients were assigned to one of two groups. Zidovudine was discontinued in group A patients before instituting GM-CSF treatment and was restarted in a graduated fashion over 4 weeks. Group B patients continued on full-dose (1,200 mg/d) zidovudine therapy while beginning GM-CSF therapy. A total of 17 patients were entered, eight in group A and nine in group B. Five of eight patients in group A and seven of nine in group B had a history of Pneumocystis carinii pneumonia (PCP). All were homosexual males, except one female in group A who was the sex partner of a bisexual male with AIDS. All patients had neutropenia (absolute neutrophil count [ANC] less than 1,000/microL) while taking full-dose zidovudine. The mean CD4 (+/- SD) lymphocyte level was 37 (+/- 29)/microL and 39 (+/- 44)/microL in groups A and B, respectively. After randomization, patients were begun on subcutaneous GM-CSF at a dose of 1.0 microgram/kg/d. Patients in group A received 2 weeks of daily GM-CSF, at which time zidovudine was restarted if the ANC was greater than 1,000/microL; if the ANC was less than 1,000/microL, the dose of GM-CSF was increased to 3.0 micrograms/kg, and at 2-week intervals either zidovudine was restarted or the dose of GM-CSF was increased to 5 micrograms/kg and then 10 micrograms/kg, to maintain the ANC greater than 1,000/microL. Group B patients received full-dose zidovudine concurrently with GM-CSF administration. The dose of GM-CSF was increased every 2 weeks if necessary to keep the ANC greater than 1,000/microL while maintaining full-dose zidovudine therapy. Patients in each group showed an increase in total white blood cell (WBC) count. Neutrophils and eosinophils were responsible for the majority of this increase. Patients in group A had a more rapid increase in WBC than those in group B; however, by week 8, the WBC in each group was essentially equal. Viral replication as measured by human immunodeficiency virus (HIV) p24 antigen (Ag) was decreased in four patients in each group, increased in one patient in each group, and remained unchanged in the remainder. The ability to culture virus from peripheral blood mononuclear cells was not changed by the regimen. The major toxicities of the regimen were fever and malaise.(ABSTRACT TRUNCATED AT 400 WORDS)
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PMID:Recombinant human granulocyte-macrophage colony-stimulating factor ameliorates zidovudine-induced neutropenia in patients with acquired immunodeficiency syndrome (AIDS)/AIDS-related complex. 174 82

This report describes the one-year results of a noncomparative study designed to assess the safety and tolerance of low-dose zidovudine (azidothymidine) given orally to 60 human immunodeficiency virus type 1-infected infants and children. At baseline, the mean age was 1.9 years (+/- 1.4), and all were symptomatic: 43% were P2A and 57% were P2B to F according to the Centers for Disease Control classification. All the patients received zidovudine for at least 6 months, and 52 of them (87%) completed a full year of therapy. The mean duration of follow-up was 346 days (+/- 42) (range, 183 to 366 days). The initial therapy consisted of four daily doses of 100 mg/m2 (400 mg/m2 per day, equivalent to 20 mg/kg per day). However, this treatment was modified when neutropenia or anemia was observed. Twenty-nine children (48%) remained at the initial therapy for the entire study. Zidovudine dosage was adjusted 92 times in the other 31 children (52%), mostly due to neutropenia (83%). Altogether, the time under full-dose therapy represented 81% of the total duration of the protocol for all patients. Children with mild symptoms, P2A at study entry, were more likely to remain under full-dose therapy than children with severe symptoms, P2B to F: the time under full-dose therapy represented 91% of the duration of the protocol for the former group and only 74% for the latter one (P less than .02). No clinical adverse experiences were attributed directly to zidovudine. Thirty-seven children were prescribed trimethoprim-sulfametoxazole as a prophylaxis for Pneumocystis carinii pneumonia.(ABSTRACT TRUNCATED AT 250 WORDS)
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PMID:Low-dose zidovudine in children with an human immunodeficiency virus type 1 infection acquired in the perinatal period. 190 64


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