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Ayalew Tefferi

Publications and source records attributed to Ayalew Tefferi.

At least 127 records · Page 7Linked to original sources
PubMed2004

Primer on medical genomics. Part XIII: Ethical and regulatory issues.

Ethics in the new genomics era has become an increasingly complex subject that often arouses passion and confusion. Although 50 years have elapsed since the elucidation of the DNA molecule, the recent near-complete sequencing of the human genome has sharply accelerated the incorporation of genetics into the medical mainstream. Along with these scientific advances, however, have surfaced challenges, liabilities, and issues regarding the processing and management of genetic information as they relate to core ethical principles such as respect for autonomy, beneficence, nonmaleficence, and justice. Institutions and state and federal governments have initiated systematic and preemptive measures in education, resource development, and protective legislation to address these cardinal ethical issues. Genetic research is also being scrutinized carefully by institutional review boards, an activity that should not be perceived as being adversarial but rather as a protective shield for investigators and research participants alike. Ultimately, it is hoped that genomics medicine will diminish rather than enhance existing sex-, race-, and socioeconomic class-based inequities in health care access and delivery. This article describes some but not all aspects of the ethical, legal, and social implications of genomics in clinical practice.

Genetics, Medical↗
PubMed2004

Durable responses to thalidomide-based drug therapy for myelofibrosis with myeloid metaplasia.

OBJECTIVE: To present the results of a long-term analysis of 2 sequential phase 2 trials of thalidomide (alone or in combination) for palliation of myelofibrosis with myeloid metaplasia (MMM). PATIENTS AND METHODS: We analyzed (March 1999 to August 2003) initial and long-term outcomes from 36 patients with symptomatic MMM who had enrolled in either our thalidomide single-agent trial (n=15) or our trial of low-dose thalidomide (50 mg/d) combined with prednisone (n=21). RESULTS: Among the 36 study patients, 20 (56%) showed some improvement in their clinical course. Response rates for specific end points included improvements in anemia (15 of 36 [42%]), thrombocytopenia (10 of 13 [77%]), or splenomegaly (5 of 30 [17%]). The combination of low-dose thalidomide and prednisone, as opposed to single-agent thalidomide, was better tolerated and more efficacious. After a median follow-up of 25 months (range, 20-56 months), 10 of 36 patients (28%) showed an ongoing response, including 8 patients in whom protocol treatment has been discontinued for a median of 21 months (range, 16-31 months). Durable treatment responses were documented for only anemia and thrombocytopenia. Treatment response was not affected by the baseline status of bone marrow fibrosis, angiogenesis, osteosclerosis, cytogenetics, or circulating myeloid progenitor (CD34) cell count. Unusual drug effects, all reversible, included leukocytosis (8 patients) and/or thrombocytosis (6 patients). CONCLUSIONS: Thalidomide (alone or combined with prednisone) is an effective first-line treatment of symptomatic anemia or thrombocytopenia in MMM. Thalidomide-based therapy has the potential to produce durable responses in MMM-associated cytopenias, even after discontinuation of the drug.

Adult↗
PubMed2004

Systemic mastocytosis: current concepts and treatment advances.

Systemic mastocytosis (SM), as opposed to cutaneous-only mastocytosis, implies the presence of neoplastic mast cell infiltration in extracutaneous tissue. Mast cell disease in adults is often systemic and often involves the bone marrow. Typical clinical and laboratory features of SM include urticaria pigmentosa, mast cell mediator symptoms (eg, headache, flushing, lightheadedness, urticaria and pruritus, nausea, diarrhea, abdominal pain, and vasodilatory shock), bone pain (eg, osteoporosis, lytic bone lesions, and fractures), hepatosplenomegaly, cytopenia, eosinophilia, elevated serum tryptase and histamine, and bone marrow fibrosis and angiogenesis. SM may be indolent (no evidence of organ dysfunction), aggressive (presence of organ dysfunction), associated with another often chronic myeloid hematologic disease (SM-AHD), or present as mast cell leukemia or sarcoma. Mast cell-mediator symptoms are treated with histamine antagonists and cromolyn sodium. Indolent SM does not require cytoreductive therapy. Aggressive SM and SM-AHD are managed based on their molecular profile. Recent information suggests that FIP1-like-1-platelet-derived growth factor receptor-alpha(+) SM responds well to imatinib mesylate, whereas interferon-alpha should be considered as a first-line treatment in all of the other cases, including patients with Asp816Val(+) SM. Cladribine has been shown to be effective in patients who develop resistance to interferon treatment.

Algorithms↗
PubMed2004

FIP1L1-PDGFRA and c-kit D816V mutation-based clonality studies in systemic mast cell disease associated with eosinophilia.

Laboratory methods to detect both FIP1L1-PDGFRA and c-kit D816V mutations were combined with immunomagnetic cell separation to study the extent of clonal involvement by both myeloid and lymphoid cells in 3 patients with systemic mastocytosis associated with eosinophilia. The results suggested an early stem cell origin for the FIP1L1-PDGFRA mutation.

Aged, 80 and over↗
PubMed2004

Pathogenesis and management of bleeding in essential thrombocythemia and polycythemia vera.

Patients with essential thrombocythemia (ET) and polycythemia vera (PV) have a paradoxical predisposition to bleeding and thrombotic complications that are major causes of morbidity and mortality. Bleeding manifestations are often associated with extreme thrombocytosis that may lead to acquired von Willebrand syndrome (AVWS). Symptomatic AVWS, in this instance, is managed by platelet cytoreductive therapy and, in case of a life-threatening situation, platelet apheresis may be of additional value. Qualitative platelet defects are prevalent in PV and ET but have not been consistently linked to clinical bleeding. However, in vitro and in vivo hemostatic defects in these disorders are either precipitated or exacerbated by the use of aspirin or other nonsteroidal anti-inflammatory drugs. Additional patient management issues are raised during systemic anticoagulation and surgery. This review summarizes putative pathogenetic mechanisms of bleeding and their management in ET and PV.

Aspirin↗
PubMed2004

Anagrelide-associated cardiomyopathy in polycythemia vera and essential thrombocythemia.

A comprehensive database inquiry at our institutions identified 11 patients with echocardiogram-documented idiopathic cardiomyopathy that post-dated a diagnosis of either polycythemia vera or essential thrombocythemia. Anagrelide therapy was temporally associated with the particular complication in 6 patients, all of whom experienced symptomatic and/or objective improvement after drug discontinuation.

Cardiomyopathies↗
PubMed2004

Bone marrow angiogenesis and its clinical correlates in myelofibrosis with myeloid metaplasia.

BACKGROUND AND OBJECTIVES: Previous retrospective studies have indicated markedly increased bone marrow angiogenesis (BMA) in myelofibrosis with myeloid metaplasia (MMM). This issue is further examined in the current prospective study and clinico-pathological correlates sought. DESIGN AND METHODS: This was a prospective single institutional study of 66 patients with bone marrow biopsy-proven MMM who were consecutively accrued. Bone marrow angiogenesis was evaluated by assessing microvessel density through immunohistochemical staining for the CD34 antigen. Laboratory and clinical information was collected concurrently. RESULTS: The 66 patients (median age 62 years, 46 males) included 36 with fibrotic phase agnogenic myeloid metaplasia (AMM), 6 with cellular phase AMM, 4 with hypocellular variant AMM, 10 with post-polycythemic myeloid metaplasia, and 10 with post-thrombocythemic myeloid metaplasia. Overall, increased BMA was documented in 61 patients (92%). All of the aforementioned sub-categories of MMM were similarly affected in terms of either grade 3 or 4 BMA but differed in the prevalence of grade 4 BMA (25%, 0%, 0%, 10%, and 10%, respectively). In a univariate analysis the only histological feature that significantly correlated with BMA was the degree of megakaryocyte clustering. Among clinical features, increased BMA was significantly associated with younger age of the patient, lower hemoglobin level, intact spleen, and absence of active therapy. On multivariate analysis, only the latter two retained their significance. INTERPRETATION AND CONCLUSIONS: The current prospective study confirms the consistent association of BMA with MMM and suggests that the process starts early, is progressive, and might be dampened by both splenectomy and drug therapy. The study also suggests either a megakaryocyte origin or a megakaryocyte effect for the putative angiogenic cytokine.

Age Factors↗
PubMed2003

Neutrophil PRV-1 expression across the chronic myeloproliferative disorders and in secondary or spurious polycythemia.

Recent studies have demonstrated neutrophil overexpression of the polycythemia rubra vera-1 (PRV-1) gene in polycythemia vera (PV) but not in secondary or spurious polycythemia (SP). To validate as well as expand upon this novel observation, we conducted a prospective study of 88 subjects: 30 with PV, 22 with SP, 14 with essential thrombocythemia (ET), 12 with myelofibrosis with myeloid metaplasia (MMM), and 10 controls. To minimize interstudy methodologic differences, we used a published real-time polymerase chain reaction (PCR)-based assay. The proportion of patients with increased neutrophil PRV-1 expression was 83% in PV, 21% in ET, 42% in MMM, 18% in SP, and 0% in controls. All 5 MMM patients with PRV-1 up-regulation had an antecedent history of PV. We conclude that neutrophil PRV-1 up-regulation is a characteristic feature of PV that may not be affected by fibrotic transformation. However, quantifying neutrophil PRV-1 mRNA, while complementary to other tests, is not in itself sufficient for the diagnosis of PV.

Case-Control Studies↗