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Query: UMLS:C0027947 (neutropenia)
 17,527 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

To assess the incidence and mechanisms of thrombocytopenia and neutropenia in neonates with Rh hemolytic disease, we studied 20 consecutive patients with this condition who were born at our hospital. All five patients with severe disease (hydrops) had neutropenia and thrombocytopenia before and after exchange transfusions. Two of six patients with moderately severe disease (not hydropic but requiring exchange transfusion) had neutropenia; all six had thrombocytopenia. Of nine patients with mild disease (not treated with exchange transfusions), two had neutropenia but none had thrombocytopenia. The mean platelet volume was low or normal (7.5 +/- 0.2 ft) in the patients with thrombocytopenia, and the neutropenia was not accompanied by a "left shift" (ratio of immature to total neutrophils 0.26 +/- 0.03, mean +/- SEM). In two severely affected patients, erythroid progenitor levels were elevated and their proliferative rates (tritiated thymidine suicide) were increased, whereas their granulocyte-macrophage progenitor levels and the proliferative rates of those progenitors were diminished. In a severely affected patient, the in vitro maturation of multipotent progenitors was altered, with production of a greater than normal proportion of normoblasts (p less than 0.01) but fewer neutrophils (p less than 0.02) and megakaryocytes (p less than 0.03). It appears that the marked increase in erythropoiesis in fetuses with Rh hemolytic disease can be accompanied by a down-modulation of neutrophil and platelet production.
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PMID:Neutropenia and thrombocytopenia in infants with Rh hemolytic disease. 249 15

Therapy of patients with the acquired immunodeficiency syndrome (AIDS) or AIDS-related complex (ARC) with azidothymidine (AZT) and 2'-3'-dideoxycytidine (ddC) is complicated by severe anemia, neutropenia, and thrombocytopenia, the cause of which is unknown. We therefore tested the effect of AZT, ddC, and an additional 2'-3'-dideoxynucleoside analogue, 2'-3'-dideoxyadenosine (ddA), on the hematopoietic progenitor cells derived from the bone marrow of normal persons and patients with AIDS/ARC. All three substances dose-dependently inhibited the in vitro colony formation of the pluripotent (CFU-GEMM), as well as the erythroid (BFU-E) and granulocyte-macrophage progenitor cells (CFU-GM). The 50% inhibition of normal progenitors by AZT occurred at 0.13 microM for CFU-GEMM, 0.32 microM for BFU-E, and 1.9 microM for CFU-GM, by ddA at 15 microM for CFU-GEMM, 40 microM for BFU-E, and 140 microM for CFU-GM. ddC was the most toxic agent and already inhibited 71% +/- 16% (mean +/- standard error of the mean [SEM]) of CFU-GEMM and 52% +/- 22% of BFU-E at 0.1 microM, whereas the 50% inhibition of CFU-GM was reached at 0.3 microM. Hematotoxicity occurred at concentrations lower than necessary to inhibit the human immunodeficiency virus (HIV), except for ddA, which is 100 times less toxic than AZT whereas its antiviral effect is only 10 times less. The inhibition of progenitor cells from AIDS patients by the 2'-3'-dideoxynucleosides was comparable to normal progenitors, except for a higher sensitivity of AIDS-derived CFU-GEMM and BFU-E to AZT.
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PMID:Inhibitory effect of azidothymidine, 2'-3'-dideoxyadenosine, and 2'-3'-dideoxycytidine on in vitro growth of hematopoietic progenitor cells from normal persons and from patients with AIDS. 254 17

The differentiation and maturation of hematopoietic progenitor cells are regulated by certain growth factors. Several of these glycoproteins have been characterized, and their amino acid sequences have been delineated. Modern DNA technology provides sufficient quantities of these hormones for testing in clinical trials. Erythropoietin (EPO) has been shown to increase the hemoglobin level and hematocrit in patients with end-stage renal disease. Granulocyte colony-stimulating factor (G-CSF) and granulocyte-macrophage CSF (GM-CSF) can increase the numbers of neutrophils and monocytes, in a dose-dependent fashion. The function of granulocytes and monocytes is also enhanced. Clinical studies of the toxicity and activity of G-CSF and GM-CSF have been conducted in patients with acquired immune deficiency syndrome, aplastic anemia, myelodysplastic syndromes, and neutropenia due to cancer and chemotherapy. In almost all patients the neutrophil count increased within 24 hours after the start of treatment. Side effects of G-CSF and GM-CSF are infrequent and usually mild. Combinations of CSFs may be even more effective.
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PMID:Clinical applications of recombinant human colony-stimulating factors. 264 25

Colony-stimulating factors (CSFs) have entered the clinical arena. Several investigators have explored, in first clinical phase I studies, different routes of administration to define the optimum biological dose, maximum tolerated dose, toxicity, and pharmacokinetics of these reagents. It has been demonstrated that recombinant human (rh) granulocyte-macrophage CSF (GM-CSF) and granulocyte CSF (G-CSF) can be safely administered over a broad dose range to increase number of circulating granulocytes in man. More recently, GM-CSF and G-CSF have been involved in phase Ib/II studies to assess the granulopoietic responses of patients with granulocytopenia due to various underlying disease states including myelodysplastic syndrome, aplastic anemia, cyclic neutropenia, Kostmann's syndrome, and the acquired immuno-deficiency syndrome. Both factors were also investigated with respect to their potential to prevent chemotherapy induced granulocytopenia or to accelerate recovery from that condition. The short-term effects of rh GM-CSF after autologous bone marrow transplantation for various solid tumors and lymphoid malignancies were assessed as well. In this article we will focus on recent results that have emerged from in vivo studies utilizing CSFs.
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PMID:Polypeptides controlling hematopoietic blood cell development and activation. II. Clinical results. 265 Jul 57

The toxicity, pharmacokinetics, and hematologic effects of granulocyte-macrophage colony-stimulating (GM-CSF) were studied in a phase I/II trial of 16 patients with myelodysplastic syndrome (MDS). The GM-CSF was administered subcutaneously (SC) daily so as to achieve prolonged blood levels and to establish an outpatient treatment regimen. Four dose levels were administered for ten days: 0.3 microgram/kg/d (three patients), 1.0 microgram/kg/d (three), 3.0 micrograms/kg/d (four), and 10.0 micrograms/kg/d (six). The most common toxicities were fever and a flu-like syndrome, which were dose-dependent. The maximum-tolerated dose was 10.0 micrograms/kg/d, which induced severe rigors (two patients), fever greater than 40 degrees C (one), severe bronchospasm (one), and WBC 60,000 (one). In one patient, refractory anemia with excess blasts in transformation (RAEB-T) progressed to acute nonlymphocytic leukemia after two doses of GM-CSF, and the patient died of leukemia that did not respond to chemotherapy. After doses of 3.0 and 10.0 micrograms/kg, serum GM-CSF levels peaked at 3.8 to 6.3 hours, and persisted for 14 and 24 hours, respectively. Circulating granulocytes (neutrophils and bands) increased in a dose-dependent manner, as 11 of 13 patients who received greater than or equal to 1.0 microgram/kg/d responded with a two- to 194-fold increase. Although the neutrophils usually returned to pretreatment levels shortly after stopping GM-CSF, two patients continue to exhibit an elevation of neutrophils for 6 months. Dose-related increases in circulating monocytes and eosinophils were also noted. Transient increases in platelet and reticulocyte counts were observed in two and three patients, respectively. Five of the 16 patients later received maintenance GM-CSF at 3 micrograms/kg/d for 2 to 9 weeks. All showed a dramatic increase in neutrophils after 2 weeks. Thereafter, despite continued therapy, the neutrophil count in four patients declined markedly. In conclusion, GM-CSF is well tolerated by the SC route and induces striking, but usually temporary, improvement in the neutropenia of MDS. Larger prospective phase III trials will determine the duration of hematologic responses and the impact on infection, morbidity, and mortality.
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PMID:Subcutaneous granulocyte-macrophage colony-stimulating factor in patients with myelodysplastic syndrome: toxicity, pharmacokinetics, and hematological effects. 265 78

A physiologic role for lactoferrin (Lf) has been implicated by (1) its antibacterial effect and (2) its involvement as a negative-feedback regulator for colony stimulating factor (CSF) and, therefore, granulocyte production. The isolation and purification of endotoxin-free, species-specific mouse and human Lf have enabled a study of the role of Lf both in vitro and in vivo. Injection of Salmonella typhimurium or LPS into mice resulted in a dose-dependent increase in plasma Lf. Treating normal and neutropenic mice with LPS showed that the plasma Lf level was directly related to the number of granulocytes found in the peripheral blood. The effect of neutropenia did not inhibit release of Lf. By incubating mouse bone marrow and adherent peritoneal cells with 0.1 microM mouse or human Lf in the absence or presence of the prostaglandin synthesis inhibitor, indomethacin (1.0 microM), no evidence could be obtained in support of a negative-feedback regulation of CSF. In fact, rather than an inhibition of CSF, the production of the latter was found to be stimulated from both cell types. Injection of endotoxin-free, mouse Lf (2 mg/animal) into mice at concentrations in the same order of magnitude as that found during bacterial infection, resulted in an increase in CSF production by 12 hours and prior to the increase in bone marrow granulocyte-macrophage progenitor cells (GM-CFC) at 48 hours. The results do not support a negative-feedback regulation of CSF by macrophages. Instead, they can be incorporated into a "demand signal" model for CSF production by macrophages.
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PMID:Lactoferrin stimulates colony stimulating factor production in vitro and in vivo. 267 3

Two siblings with congenital neutropenia are reported. The first patient, female, died after Pseudomonas sepsis. The second patient male, suffered from recurrent pyogenic infections, with a more benign course. Bone Marrow (BM) and Peripheral Blood (PB) analysis in the second patient revealed a reduced number of granules and myelin bodies in the PB neutrophils, suggesting a developmental defect of primary and secondary granules. BM promyelocytes were almost normal, but the myelocytes and metamyelocytes showed defective granulogenesis. The BM in vitro granulocyte-macrophage-colony-forming cell (GM-CFC) growth and the PB white blood cells (WBC) granulocyte-macrophage-colony-stimulating factor (GM-CSF) production, which were analyzed in the second patient, showed normal numbers of GM-CFC, with differentiation mostly toward monocytes and a defect in the GM-CSF production capacity. The second patient's PB mononuclear cells or serum did not inhibit normal GM-CFC when added to control BM cells. We suggest that in this specific form of congenital neutropenia, which is probably an autosomal recessive disorder, the abnormal neutrophil granule production and the defective provision of GM-CSF by PB WBC are unique pathognomonic characteristics, possibly associated with the overt neutropenia.
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PMID:Congenital dysgranulopoietic neutropenia in two siblings: clinical, ultrastructural, and in vitro bone marrow culture studies. 270 1

Administration of 3'-azido-3'-deoxythymidine (AZT) to patients with acquired immunodeficiency syndrome (AIDS) causes significant anemia and neutropenia. The bone marrow cytotoxicity of AZT has been attributed to deoxyribonucleotide pool perturbations that might result in impaired DNA synthesis in normal bone marrow elements. We examined the effect of human recombinant granulocyte-macrophage colony-stimulating factor (rGM-CSF) on AZT-mediated biochemical perturbations and in vitro growth inhibition of normal bone marrow myeloid progenitor cells. Exposure of nonadherent, bone marrow mononuclear cells (BMMC) to 100 ng/ml of rGM-CSF for 6 h resulted in approximately twofold increments in the mean intracellular deoxycytidine triphosphate (dCTP) and thymidine triphosphate (dTTP) levels. Administration of 10 microM AZT alone to BMMC for 6 h markedly reduced dCTP and dTTP levels and generated significant levels of AZT triphosphate (AZT-TP). Coadministration of rGM-CSF (100 ng/ml) along with AZT (10 microM) partly restored dCTP and dTTP levels and significantly reduced AZT-TP levels. Furthermore, simultaneous exposure of BMMC for 4 h to 100 ng/ml of rGM-CSF reduced the mean DNA incorporation of [3H]AZT (10 microM) from 27.2 to 19.1 pmol/micrograms of DNA. Additionally, the inhibitory effects of AZT (10 microM) on granulocyte-macrophage colony-forming unit (CFU-GM) colony growth were significantly reduced in the presence of 100 ng/ml of rGM-CSF. These in vitro studies suggest that rGM-CSF partly corrects AZT-mediated biochemical perturbations as well as reduces the cytotoxicity of AZT in normal human bone marrow myeloid progenitor cells.
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PMID:The effect of recombinant human granulocyte-macrophage colony-stimulating factor (rGM-CSF) on 3'-azido-3'-deoxythymidine (AZT)-mediated biochemical and cytotoxic effects on normal human myeloid progenitor cells. 278 47

A 45-year-old Caucasian female with seropositive rheumatoid arthritis was found coincidentally to have a circulating lymphocytosis (6.4 x 10(9)/l) and neutropenia (0.1 x 10(9)/l). Initial presentation was with mouth ulceration and recurrent infections. A spleen scan showed no evidence of splenomegaly and serum titres against EBV, CMV and toxoplasmosis were negative. No anti-neutrophil antibodies were found. Marrow aspiration demonstrated a lymphocytosis of 60% with reduced numbers of granular precursors. Lymphocytes in both blood and bone marrow were CD3, CD8, CD16 and HLA-DR positive. Lymphocyte conditioned medium (LCM) generated from the patient's blood lymphocytes (without phytohaemagglutinin) was found to inhibit allogeneic colony-forming unit, granulocyte-macrophage (CFU-GM) stem cells in semi-solid culture compared with control LCM. This inhibitory activity was abrogated by the cytolytic removal of CD8 cells prior to LCM production and was significantly reduced by co-culture with indomethacin. Culture of the patient's marrow at autostimulatory light density marrow cell concentrations showed poor spontaneous CFU-GM colony formation until marrow CD8 lymphocytes were removed cytolytically. Prednisolone was used therapeutically (40 mg/d) and resulted in the patient's neutrophil count rising from 0.06 x 10(9)/l to 1.1 x 10(9)/l and a fall in the total lymphocyte count to 1.9 x 10(9)/l. Reevaluation of the patient's LCM post steroid therapy showed loss of the previous inhibitory effect. The patient's neutrophil count is maintained on oral azathioprine and indomethacin.
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PMID:Inhibition of CFU-GM by prostaglandins in a case of chronic T-cell lymphocytosis and neutropenia. 281 37

The mechanisms underlying drug-induced neutropenia are poorly characterized. We have examined the mechanism of suppression of granulocytopoiesis by captopril and penicillamine using human and canine bone marrow cells in an in vitro culture system. Addition of captopril caused no significant change in granulocyte-macrophage colony formation at concentrations up to 30 micrograms/ml. In the presence of CuSO4 (1-3 micrograms/ml), however, captopril caused significant inhibition of colony growth (p less than 0.05). Penicillamine, another agent associated with neutropenia and, like captopril, having a reactive thiol group, also inhibited colony formation in the presence of copper. Chemical congeners of captopril lacking a reactive thiol group and enalaprilic acid, an alternative angiotensin-converting enzyme (ACE) inhibitor, failed to show inhibition, suggesting that the thiol group and not ACE inhibition was responsible. Analysis of day-7 colonies (98% neutrophilic) and day-21 colonies (37% neutrophilic, 30% macrophagic, 27% eosinophilic, and 6% mixed) showed that neutrophil-containing colonies, but not nonneutrophilic colonies were inhibited by the addition of captopril plus copper. Catalase totally reversed the inhibition of colony formation caused by these agents. Direct measurement of oxygen consumption in the presence of captopril showed marked enhancement with the addition of CuSO4 and a 48% reduction in the presence of added catalase. These data indicate that drugs with a reactive thiol group can interact with copper to generate H2O2, which can be toxic to neutrophilic progenitor cells. We postulate that this may be an important mechanism for drug-associated neutropenia and a general mechanism for drug-induced marrow cell injury.
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PMID:Suppression of in vitro granulocytopoiesis by captopril and penicillamine. 284 Nov 47


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