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S Bonanomi

Publications and source records attributed to S Bonanomi.

10 recordsLinked to original sources

Allogeneic bone marrow stem cell transplantation following CD34+ immunomagnetic enrichment in patients with inherited metabolic storage diseases.

T-cell depletion is an essential step in reducing the risk of graft-versus-host disease (GVHD) in patients with inherited metabolic storage diseases (IMSD) undergoing hematopoietic stem cell transplantation. This goal can be achieved either by selective removal of T cells or by positive selection of CD34+ cells. Large-scale preparations of purified CD34+ cells from bone marrow products have not been extensively described. We report our results with bone marrow CD34+ cell enrichment using the CliniMACS system in eight children with IMSD. The median recovery of positively selected CD34+ cells was 46.2% with a purity of 97.5%, and a residual T cell content of 0.04 x 10(6). A median of 5.5 x 10(6)/kg of CD34+ cells was infused. All patients engrafted at a median time of 12 days and none of the patients developed GVHD. This method is technically feasible and can be successfully used to transplant children with IMSD.

Antigens, CD34↗

Red blood cell support and alloimmunization rate against erythrocyte antigens in patients undergoing hematopoietic stem cell transplantation.

We retrospectively analyzed red blood cell (RBC) support and alloimmunization rate in 218 consecutive patients - 128 from the Pediatric Department and 90 from the adult Hematology Department - undergoing hematopoietic stem cell transplantation (HSCT) between 1994 and 2000. In the pre-HSCT period, the pediatric patients undergoing auto-HSCT required more RBC support. In the post-HSCT period, pediatric patients transplanted with an unrelated donor required more RBC support (median 13.5 U/10 kg bw) than patients receiving HSCT from a related donor (median 6 U/10 kg bw) or from an autologous source (median 4 U/10 kg bw, P=0.0004). In the pre-HSCT period, 159 out of 218 patients (73%) received a total of 1843 RBC units, with an overall median of 9 U/patient over a median of 24 months (range 4-62); 10 patients (6%) developed a total of 12 alloantibodies, with an alloimmunization rate of 5.4/1000 RBC units. In the post-HSCT period, all but three patients were given a total of 2420 RBC units, with an overall median of 6 U/patient over a median of 4 months (range 1-18); all but one of the pre-existing alloantibodies disappeared and three patients (1%) developed new alloantibodies with an alloimmunization rate of 1.2/1000 RBC units. These newly produced alloantibodies (one anti-M and two anti-E) were detected at +58, +90 and +210 days after HSCT. These findings might suggest a different approach to alloantibody screening tests in patients receiving HSCT, with a subsequent reduction of costs and laboratory workload.

Adolescent↗

Rituximab for immune hemolytic anemia following T- and B-Cell-depleted hematopoietic stem cell transplantation.

The treatment of immune-mediated hemolytic anemia (IHA) complicating hematopoietic stem cell transplantation (HSCT) is often unsatisfactory. We report a case of IHA which occurred after T- and B-cell depleted unrelated donor HSCT carried out for mucopolysaccharidosis type I-H (Hurler syndrome) which was successfully treated with anti-CD20+ monoclonal antibody

Anemia, Hemolytic, Autoimmune↗

Peripheral blood stem cell collection in children with acute leukemia: effectiveness of the 'DIAVE' mobilizing regimen.

Few experiences of peripheral blood (PB) hematopoietic stem cell mobilization for autologous transplantation have been reported to date in children with acute leukemia (AL). The five-drug-chemotherapy 'DIAVE' (dexamethazone, idarubicine, cytosine-arabinoside, vincristine, etoposide), followed by G-CSF, previously reported as consolidation, was adopted as a mobilization regimen in 29 children (median age: 8 years, range: 3-21; median weight: 34 kg, range: 15-73) with ALL in second remission (CR2: 21), in CR3 (2) or ANLL in CR1 (6). A median peak of 94 x 10(6) CD34(+)cells/l (range: 10-604) was reached at a median time of 12 days (range: 10-18) after the beginning of the mobilizing regimen, which was well tolerated. A median of 10.9 x 10(6) CD34(+)cells/kg (range: 2.4-56.6) were collected in 25 patients (86%), approaching 40 x 10(6)/l CD34(+) cells in the PB (ALL in CR2: 20/21, in CR3: 0/2; ANLL: 5/6) by means of one (20) or two (5) leukaphereses; a median of 2.5 blood volumes was processed. Patients with ANLL mobilized more cells than patients with ALL; moreover, the shorter the interval between remission and mobilizing therapy, the higher was the yield. The products collected underwent purification, aiming at achieving complete removal of possibly contaminating leukemic cells, in 21 cases; also, unmanipulated aliquots were stored as rescues for all but one patient. All the 23 patients undergoing transplantation engrafted (ANC >0.5 x 10(9)/l) at a median of 12 days. In conclusion, the DIAVE regimen compares favorably with conventional mobilizing regimens, usually containing cyclophosphamide, in terms of low toxicity, collection time predictability, and efficacy, as shown by the high proportion of patients mobilizing, the large amounts of stem cell collected by means of one or two leukaphereses only, and the prompt engraftment after infusion.

Acute Disease↗

Purified autologous grafting in childhood acute lymphoblastic leukemia in second remission: evidence for long-term clinical and molecular remissions.

Autologous transplantation is a treatment option for relapsed childhood acute lymphoblastic leukemia (ALL) in second complete remission (CR2) when a suitable donor is not available. In an attempt to prevent relapses originating from graft leukemic contamination, the experimental protocol of in vitro purification of leukapheretic products with monoclonal antibodies (MoAbs), previously reported for adults, was adopted in 11 of 12 consecutive patients (median age, 9 years) with B cell precursor ALL in CR2 after late relapse (median, 37; range, 31-51 months after the onset) enrolled between July 1997 and July 1999 at a single pediatric center. At a median of 12 days after the mobilizing chemotherapy followed by G-CSF, a median of 13.9 (range, 5.9-18.7) x 10(6) CD34+ cells/kg were collected from each patient and a median of 7.5 (range, 4.1-12.6) x 10(6) CD34+ cells/kg underwent the purification procedure. The first step of immunorosetting allowed a one-log reduction of the total cell count, by eliminating more than 90% of the CD11b+ cells; the second step, performed after incubation with anti-CD19 MoAbs, allowed the depletion of 99% (range, 93-100) of the CD19+ cells, kept within the magnetic field of the immunodepletion column, with a median recovery of 73% (range, 55-87) of the collected CD34+ cells. Molecular analysis assessed the in vitro eradication of detectable leukemic cells. A median reinfusion of 5.2 (range, 3.2-9.1) x 10(6) CD34+ cells/kg for each patient (median viability, 90%), after conditioning with the 'TBI-VP16-CY' regimen, allowed prompt engraftment and immunological reconstitution; no patients experienced severe transplant-related toxicity or major infections. One patient relapsed 7 months after transplantation, while 10 patients are alive in clinical and molecular remission, at a median follow-up of 29 months (range, 15-40) (2-year EFS, 89%, s.e. 9). In conclusion, the procedure proved to be reproducible for pediatric purified autografting, highly efficient concerning stem cell recovery and depletion of leukemia-lineage specific cells, and promising in terms of final outcome.

Adolescent↗

Impact of thrombotic thrombocytopenic purpura on leukemic children undergoing bone marrow transplantation.

Thrombotic thrombocytopenic purpura (TTP) has emerged as one of the main transplant-related complications over the last 15 years. The current study defines the incidence and the risk factors for the occurrence of TTP in 131 consecutive leukemic children who were transplanted between January 1994 and December 1997 at four Italian pediatric centers. Patients with ALL (101), AML (21), MDS (9), underwent an HLA-identical sibling BMT (82) or an HLA-identical unrelated BMT (49), receiving a conditioning regimen consisting of high-dose chemotherapy in 24 patients and of F-TBI combined with high-dose chemotherapy in 107 patients. The diagnosis of TTP was retrospectively evaluated on the basis of parallel criteria. TTP treatment varied according to the protocol of each treatment center. Twenty-eight of 131 patients (21.4%) developed TTP at a median of 46 days (range 21-80) after BMT. Multivariate analysis demonstrated that the risk of TTP was higher in patients who underwent unrelated BMT (P value = 0.02). Acute GVHD, stage of disease at BMT, conditioning with TBI, gender, age, did not appear to be associated with the occurrence of TTP. As to the outcome, TTP resolved in 19 patients while in nine it was the principal cause of death (32.1%). In patients with TTP, LDH peak value was the only statistically significant factor (P = 0.001) related to severe TTP. In conclusion, our experience demonstrates that leukemic children undergoing BMT, especially from an unrelated donor, should be carefully assessed for TTP which appears to be a severe and relatively common transplant-related complication when strict diagnostic criteria are applied.

Acute Disease↗

[Fertilization in vitro and embryo transfer].

After a brief historical survey and review of the main Swiss centres engaged in medically assisted procreation, the indications for in vitro fertilization and embryo transfer (IVF-ET) are discussed. This technique offers the sterility specialist a new approach in allowing separate investigation of the two gametes and study of their interactions. This therapeutic approach to infertility is thus supplemented by biological data which may modify or highlight some of the etiologic aspects and promote new treatments. The techniques employed at our centre and the results obtained over the past four years are presented. Analysis of IVF pregnancies shows that the obstetric risks can be associated with the characteristics of the groups treated rather than with the IVF technique.

Corpus Luteum Maintenance↗