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

A 44-year-old woman had a transient ischemic stroke, fibroelastoma of the mitral valve being the source of the embolus. The patient evolved with neutropenia induced by ticlopidine after 10 days of treatment. We report the major clinical features, therapeutical options, and medicamentous toxicity resulting from the use of antiplatelet drugs.
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PMID:Fibroelastoma of the mitral valve as a cause of transient ischemic stroke. 1150 Jul 51

Data accumulated over the last 10 years have led to the popular hypothesis that neutrophils and other inflammatory cells play a prominent role in the neuropathology of cerebral ischemia. This hypothesis was derived from a large number of studies involving three general observations: (1) leukocytes, particularly neutrophils, are present in ischemic tissue at the approximate time that substantial neuronal death occurs; (2) neutropenia is sometimes associated with reduced ischemic damage; and (3) treatments that prevent leukocyte vascular adhesion and extravasation into the brain parenchyma can be neuroprotective. This review reexamines the literature to ascertain its support for a pathogenic role for neutrophils in ischemia-induced neuronal loss. To accomplish this goal, we employed several logical theorems of "cause-effect" relationships, as they pertain to leukocytes and ischemic brain damage. Since the majority of studies focused on neutrophils as the most likely pathogenic inflammatory cell, this review necessarily does so here. We reasoned that if neutrophils play an important pathogenic (i.e., cause-effect) role in the neuronal damage that follows a stroke, then one should expect to find clear evidence that: (1) neutrophils invade the ischemic area prior to terminal stage infarction, (2) greater numbers of early appearing neutrophils are accompanied by evidence of greater neuronal loss, and (3) dose-related inhibition of neutrophil trafficking or activity produces a corresponding decrease in the degree of brain damage following ischemia. This review of the literature reveals that the existing evidence does not readily support any of these predictions and that, therefore, it consistently falls short of establishing a clear cause-effect relationship between leukocyte recruitment and the pathogenesis of ischemia. While the available evidence does not necessarily rule out a potential pathogenic role of neutrophils and other leukocytes, it nevertheless does expose serious weaknesses in the existing studies intended to support that hypothesis. For this reason we also offer suggestions for additional experiments and the inclusion of control groups that, in the future, might provide more effective or conclusive tests of the hypothesis.
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PMID:The role of leukocytes following cerebral ischemia: pathogenic variable or bystander reaction to emerging infarct? 1177 49

In patients with transient ischemic attack (TIA) or ischemic stroke of noncardiac origin, antiplatelet drugs are able to decrease the risk of stroke by 11% to 15%, and decrease the risk of stroke, myocardial infarction (MI), and vascular death by 15% to 22%. Aspirin leads to a moderate but significant reduction of stroke, MI, and vascular death in patients with TIA and ischemic stroke. Low doses are as effective as high doses, but are better tolerated in terms of gastrointestinal side effects. The recommended aspirin dose, therefore, is between 50 and 325 mg. Bleeding complications are not dose-dependent, and also occur with the lowest doses. The combination of aspirin (25 mg twice daily) with slow-release dipyridamole (200 mg twice daily) is superior compared with aspirin alone for stroke prevention. Ticlopidine is effective in secondary stroke prevention in patients with TIA and stroke. For some end points, it is superior to aspirin. Due to its side-effect profile (neutropenia, thrombotic thrombocytopenic purpura ), ticlopidine should be given to patients who are intolerant of aspirin. Prospective trials have not indicated whether ticlopidine is suggested for patients who have recurrent cerebrovascular events while on aspirin. Clopidogrel has a better safety profile than ticlopidine. Although not investigated in patients with TIA, clopidogrel should also be effective in these patients assuming the same pathophysiology than in patients with stroke. Clopidogrel is second-line treatment in patients intolerant for aspirin, and first-line treatment for patients with stroke and peripheral arterial disease or MI. A frequent clinical problem is patients who are already on aspirin because of coronary heart disease or a prior cerebral ischemic event, and then suffer a first or recurrent TIA or stroke. No single clinical trial has investigated this problem. Therefore, recommendations are not evidence-based. Possible strategies include the following: continue aspirin, add dipyridamole, add clopidogrel, switch to ticlopidine or clopidogrel, or switch to anticoagulation with an International Normalized Ratio (INR) of 2.0 to 3.0. The combination of low-dose warfarin and aspirin was never studied in the secondary prevention of stroke. In patients with a cardiac source of embolism, anticoagulation is recommended with an INR of 2.0 to 3.0. At the present time, anticoagulation with an INR between 3.0 and 4.5 cannot be recommended for patients with noncardiac TIA or stroke. Anticoagulation with an INR between 3.0 and 4.5 carries a high bleeding risk. Whether anticoagulation with lower INR is safe and effective is not yet known. Treatment of vascular risk factors should also be performed in secondary stroke prevention.
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PMID:Antithrombotic Secondary Prevention After Stroke. 1219 15

Patients with sickle cell disease (N = 3) and thalassemia (N = 1) with high-risk features received hematopoietic stem cell transplantations (HCT) to induce stable (full or partial) donor engraftment. Patients were 9-30 years of age. Fludarabine, rabbit anti-thymocyte globulin (ATG), and 200 cGy total body irradiation were administered pre-transplant. Patients received bone marrow (N = 3) or peripheral blood stem cells (N = 1) from HLA-identical siblings, followed by mycophenolate mofetil and cyclosporine for post-grafting immunosuppression. Significant lymphopenia, but only moderate neutropenia and thrombocytopenia developed post transplant. No grade IV nonhematological toxicities or acute graft-versus-host disease (GVHD) were observed. At 3 months after transplantation, three of four patients had evidence of donor myeloid chimerism (range, 15-100%). However, after post transplant immunosuppression was discontinued, graft rejection occurred in all but one patient. This patient is now doing well 27 months post transplant with full donor engraftment. One patient died after a second transplant, and another patient experienced a stroke as her graft was being rejected. These results suggest that stable donor engraftment after nonmyeloablative HCT is difficult to achieve among immunocompetent patients with hemoglobinopathies and that new approaches will need to be developed before wider application of this transplantation method for hemoglobinopathies.
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PMID:Hematopoietic stem cell transplantation for multiply transfused patients with sickle cell disease and thalassemia after low-dose total body irradiation, fludarabine, and rabbit anti-thymocyte globulin. 1553 1

Patients experiencing stroke or transient ischemic attack (TIA) are at high risk for recurrent (secondary) strokes, which comprise 29% of all strokes in the United States. Current recommendations for prevention of secondary stroke from the American College of Chest Physicians (ACCP) call for the broad use of platelet antiaggregation (antiplatelet) agents for patients with a history of noncardioembolic stroke or TIA. Five agents--aspirin, ticlopidine, clopidogrel, extended-release dipyridamole (ER-DP), and triflusal--have demonstrated efficacy in large-scale clinical studies in the prevention of recurrent vascular events and/or stroke in patients with a history of stroke. The results of the following studies are reviewed and compared: the Swedish Aspirin Low-Dose Trial (SALT), the United Kingdom Transient Ischaemic Attack (UK-TIA) Aspirin Trial, Dutch Transient Ischemic Attack (Dutch TIA) study (aspirin), the Canadian American Ticlopidine Study (CATS), the Ticlopidine Aspirin Stroke Study (TASS), the African American Antiplatelet Stroke Prevention Study (AAASPS) (ticlopidine), the Clopidogrel versus Aspirin in Patients at Risk of Recurrent Ischemic Events (CAPRIE) trial, the Management of Atherothrombosis With Clopidogrel in High-Risk Patients study (MATCH) (clopidogrel), the second European Stroke Prevention Study (ESPS2) (aspirin plus ER-DP), and the Triflusal versus Aspirin in Cerebral Infarction Prevention (TACIP) study. In comparative monotherapy studies of patients with previous stroke, ticlopidine demonstrates statistically significant improved efficacy over aspirin, and clopidogrel demonstrates nonsignificant slight improvement over aspirin for the prevention of ischemic cardiac and cerebrovascular events; however, the adverse event profile of ticlopidine (including rash, diarrhea, and neutropenia) will probably limit its long-term use. Among combination approaches, only aspirin plus ER-DP has demonstrated statistically significant, clinically meaningful additive benefit over monotherapy with each agent. Clopidogrel plus aspirin did not significantly improve preventive efficacy and increased the risk of serious side effects, including life-threatening bleeding episodes. The 15,500-patient PRoFESS (the Prevention Regimen for Effectively Avoiding Second Strokes) study, with results expected in 2008, will directly compare aspirin plus ER-DP with clopidogrel monotherapy for the prevention of recurrent stroke and should provide statistically robust estimates of comparative efficacy for the development of improved recommendations.
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PMID:Review of antiplatelet therapy in secondary prevention of cerebrovascular events: a need for direct comparisons between antiplatelet agents. 1621 Dec 3

(1) Chemotherapy does not appear to prolong the survival of patients with inoperable pleural mesothelioma, and the tumour response rate barely exceeds 20%. A combination of cisplatin + doxorubicin seems to provide the best response rates. (2) In a trial of second-line docetaxel therapy in patients with non small cell lung cancer, survival was extended by about 3 months compared with palliative care (7.5 versus 4.6 months). (3) Pemetrexed, an antifolate closely related to methotrexate and raltitrexed, has been authorized for use for both conditions. (4) In a randomised single-blind trial involving 456 patients with previously untreated pleural mesothelioma, survival was prolonged by about 3 months by a cisplatin + pemetrexed combination in comparison with cisplatin + placebo (12.1 versus 9.3 months). The respective tumour response rates were 41.3% and 16.7%. This is the only available comparative trial of pemetrexed in patients with mesothelioma. A more appropriate comparator would have been a cisplatin-based regimen such as cisplatin + doxorubicin. (5) A "non inferiority" trial of second-line treatment in 571 patients with locally advanced or metastatic non small cell lung cancer showed no significant difference in median survival time with pemetrexed versus docetaxel (about 8 months with both treatments). However, this trial does not rule out the possibility that pemetrexed is less effective than docetaxel. (6) Supplementation with folic acid and vitamin B12 reduces haematological and gastrointestinal complications associated with the antifolate activity of pemetrexed. (7) Despite this supplementation, more than 15% of patients in the mesothelioma trial developed severe neutropenia, leukopenia or fatigue during cisplatin + pemetrexed therapy. Pemetrexed aggravates the nausea and vomiting provoked by cisplatin, a drug that is highly emetic. (8) The adverse effects of pemetrexed were similar to those of docetaxel in the trial comparing the two drugs. However, neutropenia (5% versus 40%) and febrile neutropenia (2% versus 13%) occurred less frequently with pemetrexed. (9) Patients receiving pemetrexed must be monitored closely for some rare but potentially severe adverse effects; they include angina, myocardial infarction and stroke, liver damage, and bullous skin rash. (10) According to the summary of product characteristics (SPC), pemetrexed therapy must be administered in combination with folic acid and vitamin B12 supplementation in order to reduce haematological toxicity, and also with corticosteroid therapy to reduce the risk of serious skin reactions. (11) In practice, given the absence of a better alternative, and pending the results of a second trial, the cisplatin + pemetrexed combination can be used as a first-line regimen for patients with pleural mesothelioma. However, pemetrexed cannot replace docetaxel in second-line treatment of non small cell lung cancer.
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PMID:Pemetrexed: new drug. Pleural mesothelioma: a first encouraging trial. 1640 Jul 41

Barth syndrome is an inherited disorder characterized by dilated cardiomyopathy, neutropenia, growth retardation, and skeletal myopathy. We describe a case of acute stroke owing to Barth syndrome that required intra-arterial thrombolysis. This case suggests that cardiovascular complications can be observed in patients with Barth syndrome. Stroke prevention measures, including the use of antithrombotic agents, might be warranted.
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PMID:Stroke associated with Barth syndrome. 1697 Aug 91

Systemic inflammatory stimuli, such as infection, increase the risk of stroke and are associated with poorer clinical outcome. The mechanisms underlying the impact of systemic inflammatory stimuli on stroke are not well defined. We investigated the impact of systemic inflammation on experimental stroke and potential mechanisms involved. Focal cerebral ischemia was induced by intraluminal filament occlusion of the middle cerebral artery (MCAo). Brain damage and neurological deficit 24 h after MCAo were exacerbated by systemic lipopolysaccharide (LPS) administration. This exacerbation was critically dependent on interleukin (IL)-1, because coadministration of IL-1 receptor antagonist abolished the effect of LPS on brain damage. Systemic administration of IL-1 increased ischemic damage to a similar extent as LPS and also exacerbated brain edema. IL-1 markedly potentiated circulating levels of the acute phase proteins, serum amyloid A and IL-6, and the neutrophil-selective CXC chemokines, KC and macrophage inflammatory protein-2. Neutrophil mobilization and cortical neutrophil infiltration were aggravated by IL-1 before changes in ischemic damage. Neutropenia abolished the damaging effects of systemic IL-1. These data show for the first time that an acute systemic inflammatory stimulus is detrimental to outcome after experimental stroke and highlight IL-1 as a critical mediator in this paradigm. Our data suggest IL-1-induced potentiation of neutrophil mobilization via CXC chemokine induction is a putative mechanism underlying this effect. Our results may help to explain the poorer outcome in stroke patients presenting with infection and may have implications for neurodegenerative diseases involving neurovascular alterations, such as Alzheimer's disease, in which systemic inflammation can modulate disease progression.
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PMID:Systemic inflammatory stimulus potentiates the acute phase and CXC chemokine responses to experimental stroke and exacerbates brain damage via interleukin-1- and neutrophil-dependent mechanisms. 1744 25

A 36-year-old transfusion-dependent thalassemia major patient presented with febrile neutropenia and anemia. Deferiprone (L1) was discontinued as it was suspected to be the offending agent and prompt broad-spectrum antibiotic therapy was initiated after which the patient improved. After 11 days the patient developed hemorrhagic stroke and seizure whereby aspirin was discontinued and supportive therapy was given. Agranulocytosis is the most serious complication reported with L1 but, to the best of our knowledge, there are no previous reports on hemorrhagic stroke associated with the use of the agent, and hence, the etiology of the stroke which followed agranulocytosis caused by L1 remains obscure.
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PMID:Febrile neutropenia and hemorrhagic stroke in a thalassemia major patient. 1799 86

The clinical application of G-CSF is broadening. In addition to treating neutropenia and in bone marrow transplants, it is now being considered for functional recovery after myocardial infarction and stroke. It is thus very important that the effects of extended G-CSF administration on the skeleton are investigated. To simulate this potential clinical use of G-CSF in postmyocardial infarction or cerebral vascular accident, a 2-week course of administration was selected. Ten C57BL/6 mice at 22 weeks of age were given intraperitoneal injection of saline, and another nine of the same age were given G-CSF. Four weeks later, femurs were harvested and three-point-bend tests were performed until fracture. From the load-displacement curve recorded during the test, the stiffness, Young's modulus, fracture strength of the bone, fracture energy, and the total energy to break the femur were determined. The test data show that mice treated with G-CSF have significantly lower modulus in their femurs when compared to the controlled mice treated with saline. The stiffness demonstrates the largest decrease, by as much as 25%. As its clinical use increases, G-CSF effects on the mechanical properties of the skeleton become increasingly more important because many of these diseases occur in older patients with already compromised skeleton by osteopenia or osteoporosis. How G-CSF administration achieves these alterations in skeletal biomechanical properties is unclear. Although the current findings confirm its known temporary catabolic effects on bone homeostasis, it also suggests that a transient state of higher bone compliance following the end of G-CSF administration can be achieved that may have clinical benefits.
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PMID:Granulocyte colony-stimulating factor administration alters femoral biomechanical properties in C57BL/6 mice. 1825 84


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