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P M Stefani

Publications and source records attributed to P M Stefani.

11 recordsLinked to original sources

Heparin-induced thrombocytopenia.

BACKGROUND AND OBJECTIVE: There are two types of heparin-induced thrombocytopenia (HIT). HIT I is characterized by a transitory, slight and asymptomatic reduction in platelet count, occurring in the first 1-2 days of therapy, that resolves spontaneously; in contrast, HIT II, which has an immunologic origin, is characterized by a significant thrombocytopenia generally after the fifth day of therapy that usually resolves in 5-15 days only after therapy withdrawal. HIT II is the most frequent and dangerous side-effect of heparin therapy; in fact, in spite of thrombocytopenia, it can be complicated by venous and arterial thrombosis. Therefore, the recognition of HIT II may be difficult due to the underlying thrombotic symptoms for which heparin is administered. The aim of this article is to review the most recent advances in the field and to give critical guidelines for the clinical diagnosis and treatment of HIT II. STATE OF THE ART: The prevalence of HIT II, as confirmed by laboratory tests, seems to be about 2% in patients receiving unfractionated heparin (UH), while it is much lower in those receiving low molecular weight heparin (LMWH). The immunologic etiology of HIT II is largely accepted. Platelet factor 4 (PF4) displaced from endothelial heparan sulphate or directly from the platelets, binds to the heparin molecule to form an immunogenic complex. The anti-heparin/ PF4 IgG immunocomplexes activate platelets and provoke an immunologic endothelial lesion with thrombocytopenia and/or thrombosis. The IgG anti-heparin/PF4 immunocomplex activates platelets mainly through binding with the FcgRIIa (CD32) receptor. The onset of thrombocytopenia is independent of the dosage, schedule and route of administration of heparin. Orthopedic and cardiovascular surgery patients receiving post-surgical prophylaxis or treatment for deep venous thrombosis are at higher risk of HIT II. Besides thrombocytopenia, cutaneous allergic manifestations and skin necrosis may be present. Hemorrhagic events are not frequent, while the major clinical complications in 30% of patients are both arterial and venous thromboses which carry a 20% mortality. The diagnosis of HIT II should be formulated on the basis of clinical criteria and in vitro demonstration of heparin-dependent antibodies. Functional tests, such as platelet aggregation and (14)C-serotonin release assay and immunologic tests, such as the search for anti-PF4/heparin complex antibodies by an ELISA method are available. If HITT II is probable, heparin must be immediately suspended and an alternative anticoagulant therapy should be initiated before resolution of thrombocytopenia and the following treatment with a vitamin K antagonist. The general opinion is to administer low molecular weight heparin (in the absence of in vitro cross-reactivity with the antibodies), heparinoids such as Orgaran or direct thrombin inhibitors such as hirudin. PERSPECTIVES: Further studies are required to elucidate the pathogenesis of HIT II and especially to discover the clinical and immunologic factors that induce the occurrence of thrombotic complications. The best therapeutic strategy remains to be confirmed in larger clinical trials.

Heparin↗

Antithrombotic drugs in the primary medical management of intermittent claudication: a meta-analysis.

BACKGROUND: There is no consensus on the efficacy of the antithrombotic drugs available for patients with intermittent claudication. METHODS: A Medline and manual search was used to identify relevant publications. Uncontrolled or retrospective studies, double reports or trials without clinical outcomes were excluded. Included studies were graded as level 1 (randomised and double- or assessor-blind), level 2 (open randomised), or level 3 (non-randomised comparative). Mortality, cerebro- or cardiovascular events, amputations, arterial occlusions or number of revascularization procedures performed in the lower limbs, pain-free and total walking distance, ankle brachial index and calf blood flow, were the main outcomes considered. When feasible, end of treatment results, either continuous or binary, were combined with appropriate statistical methods. RESULTS: Mortality was significantly decreased by ticlopidine compared to placebo (common odds ratio 0.68, 95% C.I., 0.49 - 0.95); clopidogrel decreased vascular events in comparison to aspirin (odds ratio 0.76, 95% C.I., 0.63 - 0.92) in level 1 studies. Arterial occlusions and the number of revascularization procedures performed were statistically significantly decreased by aspirin and ticlopidine, respectively. A small but statistically significant improvement in pain-free walking distance was determined by picotamide, indobufen, low molecular weight heparins, sulodexide and defibrotide, in small studies. CONCLUSIONS: Clopidogrel and ticlopidine do reduce clinically important events in patients with intermittent claudication and could be added to the primary medical treatment of these patients. The use of aspirin in these patients cannot be based on direct evidence, but only on analogy with coronary and cerebral atherosclerosis, where it has documented efficacy. Other antithrombotic drugs were not properly evaluated in patients with intermittent claudication.

Fibrinolytic Agents↗

Prevalence and patterns of symptomatic thromboembolism in oncohematology.

BACKGROUND AND OBJECTIVE: Approximately 15% of patients with cancer will experience a thrombotic episode at some time. Some patients are at particularly high risk depending on the histology of the malignant disease. The aim of the study was to determine the actual prevalence of thrombotic episodes in oncohematologic patients. DESIGN AND METHODS: We conducted a retrospective cohort analysis on a total of 515 patients that were admitted to the out-patients clinic (Institute of Medical Semeiotics) from January 1, 1986 to January 31, 1996. Two main groups were selected for this study: 133 patients suffering from a myeloproliferative disorder and 382 patients affected by a lymphoproliferative disorder. Follow-up lasted a median of 33 months in both groups (range 3-144 months). The difference between the observed events for each group was estimated by the odds ratio and chi square. Age and sex distribution were estimated by the Mann-Whitney test. Distribution of overall survival was estimated by the Kaplan-Meier method and compared between groups (DVT patients and non DVT patients) by the log-rank test. RESULTS: Twenty-three patients experienced a venous thrombotic disorder. The prevalence of deep vein thrombosis (DVT) in myeloproliferative and lymphoproliferative disorders was 8.27% (n = 11) and 3.14% (n = 12) respectively (odds ratio = 0.36; 95% CI = 0.14-0.90; chi-square = 4.94 p = 0.028). DVT was apparently idiopathic in 17 cases. In 4 patients another cancer was present; in the remaining 2 patients the thrombotic episode was associated with other predisposing factors. Although 7 of the 23 patients with DVT died, we cannot find any difference in the overall survival compared to oncohematologic patients who did not experience DVT. INTERPRETATION AND CONCLUSIONS: The prevalence of symptomatic DVT in the oncohematological patients is lower than reported for solid tumor. Patients affected by myeloproliferative disease have a higher risk of developing thrombosis. DVT if well-treated does not influence the survival of oncohematological patients.

Adolescent↗

Clinical and laboratoristic remission after cryosupernatant plasma exchange in thrombotic thrombocytopenic purpura.

We describe a case of thrombotic thrombocytopenic purpura (TTP) resistant to conventional therapy with fresh-frozen plasma (FFP)-plasma exchange (PEX) as well as to steroids, immunoglobulins, vincristine, dipyridamole, dextran and iloprost, achieving complete remission with cryosupernatant-plasma exchange. Our case shows the effectiveness of cryosupernatant PEX, when FFP-PEX and alternative therapies have failed.

Adult↗

Hypertriglyceridemia during long-term interferon-alpha therapy in a series of hematologic patients.

Adverse reactions to interferon-alpha (IFN-alpha) therapy include flu-like syndrome, bone marrow suppression, neurotoxic effects, and autoimmunity. A slight increase in triglyceride levels has been described less frequently during IFN-alpha administration. The incidence of IFN-alpha-induced hypertriglyceridemia seems variable, and there are no clear data on how to treat it. We report the effect of long-term (more than 12 months) IFN-alpha treatment on triglyceride levels in 43 patients suffering from hairy cell leukemia (18), multiple myeloma (10), chronic myelogenous leukemia (6), cryoglobulinemia (5), non-Hodgkin's lymphoma (3), and Sezary syndrome (1). Hypertriglyceridemia was found in 6 patients (15%). In 3 patients, gemfibrozil restored normal triglyceride values. This study suggests that hypertriglyceridemia is a minor side effect of long-term IFN-alpha therapy and that gemfibrozil might be considered the treatment of choice.

Adult↗

Remission in hairy cell leukemia-variant following splenic radiotherapy alone.

The therapeutic approach to hairy cell leukemia (HCL) is in some instances still debated. A variant form of HCL (HCL-V) characterized by high white cell count, splenomegaly, hypercellular and aspirable bone marrow has been described; differential diagnosis often arises with some other B-cell disorders which also show circulating hairy or villous lymphocytes. Conventional treatment for HCL is often less effective in HCL-V. In this report we describe a case with features consistent with HCL-variant treated with splenic radiotherapy. We not only obtained an hematological response but also the near total disappearance of bone marrow infiltration, compatible with a clinical complete remission. Clinical and biological implications of this phenomenon are discussed on the basis of this unexpected therapeutic result, obtained with splenic radiotherapy alone.

Aged↗

Idiopathic myelofibrosis with neutrophil myeloperoxidase deficiency: a case report.

We describe a case of idiopathic myelofibrosis with total neutrophil myeloperoxidase deficiency. The combination of this enzymatic defect with myelofibrotic changes in the nuclear shape of neutrophils confers a peculiar appearance on leukograms produced by a Technicon H*1. The clinical course of the disease was shortened by recurrent infections that may be ascribed, at least in part, to reduced leukocyte microbicidal ability.

Bone Marrow↗

Primary breast lymphoma.

Breast involvement by non-Hodgkin lymphoma is uncommon. Differences between primary and secondary breast lymphoma have been well-defined. However, histopathological features, therapeutic approach and outcome are still debated. We report the clinical and pathological features of 5 cases of malignant lymphoma primarily involving the breast. The literature is extensively reviewed paying particular attention to pathological features, therapeutic approach and survival analysis. All patients were women; the median age was 63.2 yr. The clinical course was indistinguishable from that of breast carcinoma. High-grade lymphoma was found in 4 cases; T cell lineage antigens were expressed in one case. All patients were in stage I or II. Treatment consisted of chemotherapy and/or radiotherapy. The follow-up period ranged from 20 to 54 months (mean, 33.2). All patients are still in complete clinical remission. Analysis of the literature showed that about 80% of cases are high grade lymphoma. In this group, stage I at presentation statistically gives the best survival rate; surgery does not appear to have a role in high-grade lymphoma treatment.

Adolescent↗