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Biomedical subjects

S Guidi

Publications and source records attributed to S Guidi.

At least 55 records · Page 3Linked to original sources
PubMed1991

Early haemostatic modifications following cryopreserved graft infusion.

The nature of the graft used for the rescue of patients undergoing autologous bone marrow transplantation is that of a complex mixture of pharmacological agents and cellular debris known to have a number of effects on the haemostatic system. The present study was undertaken to evaluate the occurrence and the degree of haemostatic alterations during and immediately following graft infusion in 24 patients suffering from haematological malignancies. On day 0, before graft infusion, the majority of patients appeared with laboratory signs of enhanced thrombin generation, platelet activation, and endothelial damage, most likely due to the conditioning regimen. However, the graft infusion per se was accompanied in the short term by a further increment of some parameters indicating a thrombotic risk (as thrombin-antithrombin complex, beta-thrombo globulin, platelet factor four, and von Willebrand factor antigen, together with a concomitant prolongation of partial thromboplastin time and a reduction of prothrombin time. In contrast there was no further modification of antithrombin III or protein C levels nor an increase in fibrinopeptide A levels. We hypothesize that complex interactions between agents contained in the graft mixture and host haemostatic system are involved in the pathogenesis of the haemostatic alterations which followed cryopreserved graft infusion; however, in our series, these were not accompanied by clinical signs of thrombotic or haemorrhagic events.

Antithrombin III↗
PubMed1991

Serum erythropoietin levels in patients undergoing autologous bone marrow transplantation.

Serum erythropoietin (sEpo) levels were serially measured with a radioimmunoassay in 14 patients undergoing autologous bone marrow transplantation (BMT), starting before the institution of the conditioning regimen up to day +45. An increase in sEpo levels was observed soon after starting the chemotherapy regimen, and before an evident fall in hemoglobin (Hb) levels took place. The peak in sEPo levels (221 +/- 181 mU/ml) was reached at day 0 in 9/14 patients, and was delayed up to day + 10 in the remaining five. There was a negative correlation between loge sEpo and Hb values (r = -0.730; p less than 0.01); the regression line of this correlation was comparable to the one obtained in a group of 15 iron-deficiency anemic subjects. Therefore, patients undergoing autologous BMT appear to be able to develop adequately increased sEpo levels in response to the severity of anemia. No correlation was found between sEpo and white blood cell or platelet count. On the other hand, sEpo value at day 0 was significantly related to the day of neutrophil recovery (r = -0.806; p less than 0.001): patients with the highest sEpo levels at day 0 showed significantly faster (p less than 0.001) neutrophil recovery.

Adolescent↗
PubMed1988

Renal involvement in IgD myeloma.

Nine patients affected from IgD myeloma were studied retrospectively in order to elucidate the incidence and peculiar traits of related nephropathy. Eight patients developed chronic renal failure, and as many as 5 were already suffering from renal failure since first admission to the hospital. In 3 cases acute renal failure was the major presenting symptom of the disease. Five patients underwent a regular dialytic treatment. We suggest that the high incidence of renal involvement found in IgD myeloma is related to the high incidence of Bence-Jones proteinuria observed in this disease. Presenting atypical symptoms, among which renal failure is the most important, are misleading and characteristic of the disease. Survival time seems to be negatively influenced by the presence of renal failure at the time of diagnosis.

Adult↗
PubMed1983

Different patterns of platelet turnover in chronic idiopathic thrombocytopenic purpura.

Platelet turnover, platelet production, platelet mean life span (MLS), platelet count, mean platelet volume (MPV) and platelet-associated antibodies have been examined in 26 patients with chronic idiopathic thrombocytopenic purpura (ITP) and in 1 patient with hypomegakaryocytic thrombocytopenia (HT). 15 ITP patients had normal or increased platelet turnover and platelet production, while 11 had subnormal values despite shortened MLS, while the patient with HT had normal MLS. The differences between the two groups with high and low platelet turnover were statistically significant. No correlation was found between kinetics parameters and bone marrow pattern in a total of 19 patients examined. These data suggest that in some cases of chronic ITP, the pathogenesis of thrombocytopenia can be due not only to the peripheral destruction of platelets, but also to a deficient platelet production by megakaryocytes. Since the number of megakaryocytes in bone marrow slides is not decreased in the low turnover compared with the high turnover group, it is possible that an impaired pattern of megakaryocyte maturation be the cause of the low platelet production in these patients, unlike in the HT patient where megakaryocytes are almost absent.

Adolescent↗
PubMed1983

Chronobiological aspects of phosphohexoseisomerase in monitoring multiple myeloma.

In the field of oncology, the most important aim to date has been the finding of new means to improve the diagnosis and treatment of neoplastic diseases. Chronobiologically we have studied the behavior of phosphohexoseisomerase (PHI) in 11 multiple myeloma patients before treatment and in another group of 11 patients undergoing polychemotherapy treatment. From all patients, under the same standard conditions, 6 venous samples were taken at 4-hour intervals starting at 08.00 h, for a day. PHI serum levels were determined spectrophotometrically. The data obtained were analyzed by 'group mean cosinor' and from this analysis a mesor reduction of more than 50% was noted in subjects after polychemotherapy (M2) correlated with the absence of a circadian rhythm. The data suggest that PHI levels can be related to the characteristics of tumor growth and we feel they can be used as a guide in monitoring multiple myeloma patients.

Aged↗
PubMedDate not supplied

Allogeneic stem cell transplantation.

Allogeneic stem cell transplantation (HSCT) requires the harvest of an adequate number of stem cells (SC) from a histocompatible donor and their infusion into a patient following a conditioning regimen. During the past 35 years, the role of HSCT has changed from an experimental procedure for terminally ill patients to a curative treatment. In 2003, 1170 procedures were registered in Italy (Italian Group for Blood and Marrow Transplantation). The main reported indications were as follows: leukemia, lymphoproliferative diseases, myelodysplasia, and nonmalignant diseases such as thalassemia and severe aplastic anemia. Important changes have been observed in the last 5 years: the shift from bone marrow to peripheral blood as the SC source, the increasing number of alternative donors such as unrelated, partially matched family donors and cord blood SC, and the new extra-hematological indications including solid tumors. Moreover, the development of nonmyeloablative conditioning regimens have allowed physicians to perform HSCT in patients with advanced age or important comorbidities. In contrast, the availability of the Tyrosine kinase inhibitor (STI-571) for treatment of patients affected by chronic myelogenous leukemia, which was formerly the main indication for HSCT, has produced a dramatic decrease in the number of transplantations in this setting. HSCT performed in the early phases of disease and in young patients offers more than a 50% cure rate. The transplant-related mortality still represents the greatest obstacle, ranging from 20%-30%, despite the less toxic conditioning regimens, high-resolution HLA typing, and better supportive care. GvHD and infections remain the main causes of morbidity. As regards relapses, they correlate with disease status at the time of transplantation. Promising results have been recently obtained with haploidentical and with cord blood SC transplantation also in adult patients.

Hematologic Diseases↗
PubMedDate not supplied

Ophthalmological aspects in allogenic bone marrow transplantation: Sjögren-like syndrome in graft-versus-host disease.

PURPOSE: A major complication of allogenic bone marrow transplantation (BMT) is graft-versus-host disease (GVHD), characterized principally by involvement of the eyes, producing a Sjögren-like syndrome (SLS). This study assessed the predictive role of the eye involvement in the onset of GVHD. METHODS: Thirty-five patients transplanted for hematological malignancies were routinely examined for ocular manifestation of dry eye. Examination includes the Schirmer I test, break-up time, Lissamine Green staining, fluorescein test, lactoferrin test and impression cytology. A threshold was established for quantitative analysis of SLS. RESULTS: Fifteen of 35 patients (40%) developed SLS during long-term follow-up. Ten of these (77%) developed acute or chronic GVHD. CONCLUSIONS: The possible etiology of SLS includes three factors: total body irradiation, ocular toxicity of chemotherapy and GVHD. A correlation was found between poor-prognosis GVHD and the occurrence of SLS.

Adult↗
PubMedDate not supplied

Inadequate erythropoietin production in allogeneic bone marrow transplant patients.

BACKGROUND: There is some evidence that the erythropoietin (Epo) feedback mechanism in response to anemia can be altered in the period immediately following allogeneic bone marrow transplantation (BMT). METHODS: By using a RIA, serum erythropoietin (sEpo) levels were serially measured in 10 BMT patients, from day -10 up to day +30, and the results correlated with the concurrent hemoglobin (Hb) value. Thirty healthy subjects and 15 iron-deficiency anemic patients were used in order to construct our own reference sEpo vs Hb curve. A sEpo value recorded in BMT patients was considered to be inappropriate for any given Hb value when falling below the lower 95% confidence limit of the control curve. RESULTS: Basal sEpo levels were significantly higher than in healthy subjects, and increased further during the BMT procedure, being still higher than controls on day +30. However, Epo production resulted inappropriate for each given Hb value, when compared with the control curve, in 60 out of 67 sEpo determinations performed following graft infusion. The inadequate Epo production was not associated with the development of clinically manifest signs of kidney toxicity. CONCLUSION: These data indicate that Epo production is impaired in the period immediately following BMT and suggest a role for the administration of recombinant human Epo in the short-term management of the anemia associated with BMT.

Anemia↗
PubMedDate not supplied

Kinetics of anti-CMV antibodies after administration of intravenous immunoglobulins to bone marrow transplant recipients.

Polyspecific iv immunoglobulins (IVIG) are routinely used to prevent cytomegalovirus (CMV) infections in bone marrow transplant recipients; however, the plasma disappearance pattern of CMV-specific antibodies after administration of this product remains unclear because conflicting kinetic data have been reported previously. We studied the half-life of CMV-specific antibodies in 9 patients undergoing bone marrow transplantation after administration of 500 mg/kg of a conventional polyspecific IVIG preparation (Sandoglobulin, Sandoz Pharmaceuticals). Eight serial blood samples were drawn for kinetic evaluation after the dose. The titer of CMV-specific antibodies in the sample was determined by the FIAX method, and the decay curves of CMV-specific antibodies were analyzed kinetically using model-independent method. The 9 kinetic curves showed that a titer above 20 Fiax units was maintained for only 7 days after dosing. The mean half-life of CMV-specific antibodies was 5.6 days (range 3.5 to 12.5 days), indicating that their elimination rate was much faster than that found in several other studies. Our results suggest that the optimal dosing interval for these products is around 1 week in bone marrow transplant recipients.

Adult↗
PubMedDate not supplied

Treatment of a delayed graft failure after allogeneic bone marrow transplantation with IL-3 and GM-CSF.

We report on the partial effectiveness of sequential IL-3 and GM-CSF administration, following an ineffective 5-day trial with G-CSF, in a case of delayed graft failure after allogeneic bone marrow transplantation. Therapy with these growth factors was followed by a prompt (within 2 days) increase of neutrophil count, suggesting the possibility of a priming effect due to the previous G-CSF administration. The potential usefulness of this growth factor schedule administration in the treatment of graft failures after allogeneic bone marrow transplantation requires confirmation in controlled trials.

Adult↗
PubMedDate not supplied

Early hemostatic alterations following bone marrow transplantation: a prospective study.

BACKGROUND: The occurrence of coagulation system alterations after bone marrow transplantation (BMT) and their possible role in the pathogenesis of thrombotic complications such as veno-occlusive disease of the liver (VOD) are still a matter of debate. The aim of this study was to evaluate prospectively the alterations in hemostatic balance developing during the early period after BMT (up to day +21) and their relationships (if any) with VOD. PATIENTS AND RESULTS: Twenty-nine patients (15 autologous and 14 allogeneic BMT) entered the study. No patient suffered from thrombotic and/or major hemorrhagic events. Since there were no differences between the two groups of patients with regard to modifications of coagulation parameters, they were considered together for the purposes of the study. We observed a progressive increase from baseline levels of fibrinogen, factor VIII activity (fVIII:C) and von Willebrand factor antigen (vWf), while factor VII antigen (fVIIAg), protein C and plasminogen significantly decreased. The alterations in these test values were maximal on day +14, with a trend towards normal levels one week later. There was no modification of PT, PTT, prothrombin fragment 1 + 2 (F 1 + 2), fXIIC, tPA, PAI-1, D dimer or protein S levels; serum levels of tumor necrosis factor-alpha were also unchanged. CONCLUSIONS: These results suggest that some alterations of the hemostatic system, probably a consequence of endothelial damage, can be detected early after BMT, but their clinical significance remains uncertain due to the lack of a correlation between hemostatic test alterations and the occurrence of thrombotic complications.

Adolescent↗
PubMedDate not supplied

Prostaglandin E2 bladder instillation for the treatment of hemorrhagic cystitis after allogeneic bone marrow transplantation.

BACKGROUND: Hemorrhagic cystitis (HC) is a major complication of high-dose cyclophosphamide therapy used in the preparative regimen for allogeneic or autologous bone marrow transplantation. Several viruses (adenovirus, cytomegalovirus and polyomavirus BK) have also been implicated in the etiology of HC. No one established method of treatment is as yet available. MATERIALS AND METHODS: HC developed in 10 patients after allogeneic bone marrow transplantation and was BK viruria-associated in all cases. All patients were treated with instillations of prostaglandin E2 (PGE2) directly into the bladder. RESULTS: A complete resolution of hematuria within a short time (5 +/- 1 days) was observed in all cases; in 4/10 patients urine cleared within 24 hours of the initial treatment. Intravesical PGE2 therapy caused no systemic circulatory or respiratory problems, although bladder spasms occurred in all patients. CONCLUSIONS: Intravesical prostaglandin E2 instillation appears to be an effective treatment for hemorrhagic cystitis in bone marrow transplant patients; further studies are required to assess the actual role of BK virus in the pathogenesis of HC in bone marrow transplant patients.

Administration, Intravesical↗