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Y Bonny

Publications and source records attributed to Y Bonny.

At least 19 recordsLinked to original sources
PubMed2000

Predictors of physical outcomes in pediatric bone marrow transplantation.

The purpose of the present study was to investigate the hypothesis that family factors, in conjunction with clinical factors, are associated with physical outcomes in pediatric BMT. A prospective study of 68 pediatric patients (mean age = 7.5 years; ranging from 4 months to 18 years) undergoing BMT was carried out over a 6.5 year period. Physicians rated initial prognosis on a (0-5) scale which incorporated the child's diagnosis, known risk factors, and type of donor. Both parents individually completed two psychometrically sound questionnaires assessing family well-being and marital satisfaction. Cox proportional hazards survival analyses were performed to determine predictors of death (44% of the patients died). Potential predictor variables included were: initial prognosis, type of transplant, patient's age, socioeconomic status, marital satisfaction and family status, and family stress. Initial prognosis, as estimated by the physician, (RR = 0.62, 95% CI = 0.40, 0.97) was the best predictor of survival. Initial clinical factors are clearly critical in outcomes for pediatric BMT patients.

Actuarial Analysis↗
PubMed2000

Relapse after bone marrow transplantation: evidence for distinct immunological mechanisms between adult and paediatric populations.

Donor lymphocyte infusions are particularly effective for remission induction in malignant cells in patients who relapse after allogeneic progenitor cell transplantation (PCT) and who remain sensitive to the administration of unprimed donor T and/or natural killer (NK) cells present in donor lymphocyte infusions. To determine whether relapse after unmanipulated PCT could be ascribed to donor T and/or NK cell loss or tolerization, we evaluated the chimeric status of 81 patients with haematological malignancies who were receiving allogeneic unmanipulated PCT. The incidence of mixed chimaerism (MC) in unfractionated mononuclear leucocyte samples decreased rapidly after transplant, and was not detectable 4 months after PCT, even in patients who subsequently relapsed. The chimeric status of immune effector cell subsets was then evaluated in 15 patients at the time of relapse. All adults demonstrated complete donor haematopoiesis (CDH) for all cell lineages, whereas T- and NK-cell MC was only found in patients younger than age 13 years (P = 0.004). MC was not found in T nor NK cells of a control group consisting of age-matched paediatric patients in remission after allogeneic PCT. Thus, in adults, T and NK cell MC disappears early after unmanipulated allogeneic PCT and is absent at the time of relapse. However, the identification of donor T and NK cell loss in the paediatric relapsed but not remission patients suggests a distinct mechanism of relapse.

Adolescent↗
PubMed1999

Endocrine complications of bone marrow transplantation in children.

Eighty-seven patients had a bone marrow transplantation (BMT) at our institution between 1980 and 1992. We wished to study the endocrine complications that accompany this procedure as long-term survival is now much more common. Forty-three patients were retrospectively available for review and their records were examined for evidence of thyroid, pubertal, and growth complications. Fifteen per cent of the patients showed evidence of thyroid involvement. Pubertal delay or gonadal damage was almost universal in pubertal-aged girls treated with busulfan/cyclophosphamide. Gonadal involvement was more frequent in girls than in boys (70% vs. 47%). Sixty per cent of children were shorter or grew at a slower rate. Sixty-five per cent of the children presented with one or more endocrine complications. These are the combined effects of different treatment regimens (chemotherapy, radiotherapy, combined therapy). It is essential to know the natural history of these patients in order to offer proper guidance and treatment as survival rates are increasing.

Adolescent↗
PubMed1998

Quantitative assessment of hematopoietic chimerism after allogeneic bone marrow transplantation has predictive value for the occurrence of irreversible graft failure and graft-vs.-host disease.

Primary graft failure, secondary to either host-vs.-graft reaction or delayed engraftment, and graft-vs.-host disease (GVHD) are among the most difficult clinical problems to manage in the field of allogeneic bone marrow transplantation (BMT). Early diagnosis of both conditions would greatly improve their outcome. Using fluorescence in situ hybridization (FISH) with an X- and Y-probe mixture, we sequentially monitored chimerism of neutrophils and lymphoid cells from day 1 to 100 in 28 consecutive recipients of sex-mismatched unmanipulated bone marrow grafts. The objective was to quantitatively assess the evolution of chimerism during this crucial time interval and to determine whether chimerism patterns would be predictive of engraftment and GVHD. In recipients with primary graft failure (n=7), the presence of donor-type neutrophils and NK cells as well as the predominance of donor-type T cells distinguished patients who responded to G-CSF (n=5) from nonresponders (n=2). Furthermore, the clearance of host CD3+CD56- cells during days 5-10 posttransplantation was significantly hastened in patients who subsequently developed acute (delta=80%) or chronic (delta=81%) GVHD compared with patients without GVHD (delta=17%). Thus, our data suggest that molecular monitoring of the fate of host/donor hematopoietic cells in the early posttransplantation period could be useful in differentiating patients with delayed engraftment from those with irreversible rejection and in predicting the occurrence of GVHD as soon as day 10. This investigational approach may provide an appropriate basis on which to select adequate treatment for primary graft failure and high-risk candidates that could benefit from novel preemptive therapies for GVHD.

Bone Marrow Transplantation↗
PubMed1996

Demonstration of an osteoblast defect in two cases of human malignant osteopetrosis. Correction of the phenotype after bone marrow transplant.

Osteopetrosis is an inherited disorder characterized by bone sclerosis due to reduced bone resorption. Here we report that human osteopetrotic osteoblast-like (Ob) cells express a defective phenotype in primary cultures in vitro, and that bone marrow transplant (BMT) corrects osteoblast function. DNA analysis at polymorphic short-tandem repeat loci from donor, recipient, and primary Ob-like cells pre-BMT and 2 yr post-BMT revealed that Ob were still of recipient origin post-BMT. Osteopetrotic Ob-like cells obtained pre-BMT showed normal and abnormal 1,25(OH)2D3-induced alkaline phosphatase (ALPase) and osteocalcin production, respectively, and failed to produce macrophage colony-stimulating factor (M-CSF) in response to IL-1a and TNF-alpha. These parameters were all normalized in primary Ob-like cells prepared 2 yr post-BMT. X-linked clonality analysis at the human androgen receptor (HUMARA) locus revealed that osteoblasts showed a polyclonal and an oligoclonal derivation pre- and post-BMT respectively, indicating that a limited number of progenitor reconstituted this population. Because osteoblasts were still of recipient origin post-BMT, this suggests that functional osteoclasts, due to the replacement of hematopoeitic cells, provided a local microenvironment in vivo triggering the differentiation and/or recruitment of a limited number of functional osteoblasts.

Alkaline Phosphatase↗
PubMed1996

Long-term immunosuppressive treatment of a child with Takayasu's arteritis and high IgE immunoglobulins.

A 7-year-old child presented with a severe form of Takayasu's arteritis, with two consecutive episodes involving the right testis and then the left kidney 6 months later. The renal artery obstruction was accompanied by severe hypertension. An aortography showed a complete obstruction of the left renal artery and a narrowing of the right subclavian artery. Plasma renin activity was high. Serum immunoglobulins were within the normal range, except for an increase in IgE (880 mu/l). Despite 4 months', treatment with antihypertensive drugs, prednisone, cyclophosphamide, and anticoagulant, the blood pressure never returned to normal and the left renal function remained completely absent. A nephrectomy was performed which immediately normalized plasma renin activity and blood pressure. The child was subsequently treated with alternate-day prednisone for 3 months, alternating with 3 months of cyclophosphamide or, later, azathioprine. Persantine (dipyridamole) and acetylsalicylic acid were administered continuously. The right radial pulse returned to normal within 2 years. An 8-year follow-up failed to detect any new episode of arteritis. The right kidney showed signs of compensatory hypertrophy. Finally, a recent arteriography demonstrated not only a normal right renal artery blood flow but almost total disappearance of the right subclavian artery obstruction. However, the IgE remained abnormally high (2,023 micrograms/l).

Anticoagulants↗
PubMed1996

Leucocyte adhesion deficiency presenting as a chronic ileocolitis.

CD11/CD18 leucocyte glycoprotein deficiency is a rare, congenital adhesion molecule disorder which, in its severe form, is usually fatal. Leucocytes in affected subjects have abnormal migration and adherence, rendering patients susceptible to life threatening infections. The CD11/CD18 integrins, and other adhesion molecules, are considered essential to the normal inflammatory response. It has been postulated that adhesion molecules may be responsible for mediating in part, the inflammatory changes observed in inflammatory bowel diseases and related disorders. This report describes the first case of CD11/CD18 deficiency characterised by a chronic ileocolitis. Bone marrow transplantation completely resolved the gastrointestinal symptoms, supporting a role for neutrophil dysfunction in the pathogenesis of the gut lesions. This case suggests that specific blockade of CD11/CD18 integrins alone may not halt the chronic inflammatory response observed in immune mediated bowel disorders, and that abnormalities of leucocyte function must be included in the differential diagnosis of paediatric Crohn's disease.

Bone Marrow Transplantation↗
PubMed1995

Family factors affecting bone marrow transplantation. A case report.

Bone marrow transplantation (BMT) is the last resort for children with leukemia for whom conventional treatments have failed. The case presented herein is one of an adolescent girl whose parents were unable to cope with the extreme challenge of BMT. Couple- and family-related data collected prior to the BMT showed this family was at risk. Indeed, throughout the ordeal the patient seriously regressed and her parents' reactions appeared to exacerbate her condition. At discharge, when left alone, the patient manifested somatic symptoms which required her parents to attend to her needs. How family factors may influence BMT outcome is discussed.

Adolescent↗
PubMed1995

Distinct patterns of minimal residual disease associated with graft-versus-host disease after allogeneic bone marrow transplantation for chronic myelogenous leukemia.

PURPOSE: Allogeneic bone marrow transplantation (BMT) has been shown to provide effective therapy for chronic myelogenous leukemia (CML), but previous reports have also demonstrated the persistence of bcr-abl-positive cells for months to years after BMT in the majority of patients. To evaluate the biologic significance of persistent bcr-abl-positive cells, we examined the relationship between clinical parameters known to affect the risk of relapse and the ability to detect bcr-abl-positive cells post-BMT. PATIENTS AND METHODS: We analyzed 480 samples from 92 patients at two transplant centers for the presence of bcr-abl-positive cells by polymerase chain reaction (PCR). Two different BMT preparative regimens and protocols for prevention of graft-versus-host disease (GVHD) were used. One center used cyclophosphamide plus total-body irradiation (CY/TBI) and T-cell-depleted marrow; the second center used busulfan plus cyclophosphamide (Bu/CY) and untreated marrow with cyclosporine and methotrexate (Csp/MTX) as GVHD prophylaxis. RESULTS: We first determined the percent of patients at each center with > or = one PCR-positive (PCR+) result at defined intervals post-BMT. Between 0 and 6 months post-BMT, the majority of patients (80% to 83%) in both populations had PCR-detectable bcr-abl-positive cells. Between 6 and 24 months post-BMT, 80% to 88% of patients who received T-cell-depleted marrow remained PCR+, as compared with 26% to 30% of patients who received unmodified marrow. After 24 months post-BMT, the percentage of PCR+ patients was not significantly different in the two populations. This pattern of detection of bcr-abl-positive cells post-BMT followed the development of chronic GVHD in patients who received unmodified marrow. All patients were also divided into three groups based on post-BMT PCR results as follows: (1) persistent PCR+ (n = 29), (2) intermittent PCR-negative ([PCR-] n = 40), and (3) persistent PCR- (n = 23). These three groups were found to have a low, intermediate, and high probability of maintaining remission and disease-free survival, respectively (P = .0001). Intermittent or persistent PCR- results, which reflect levels of minimal residual disease < or = the limit of detection by PCR, were clearly associated with both acute (P = .004) and chronic (P = .000005) GVHD. Nevertheless, 44% of patients without GVHD also had intermittent or persistent PCR- assays. CONCLUSION: The persistence of PCR-detectable bcr-abl-positive cells early post-BMT in more than 80% of patients suggests that neither BMT preparative regimen effectively eradicates CML cells in most patients. Subsequently, acute and/or chronic GVHD are associated with a decreased ability to detect residual bcr-abl-positive cells, which suggests that immunologic mechanisms mediated by donor cells are important for inducing long-term remissions after BMT. The demonstration that 44% of patients without GVHD had either low or undetectable levels of residual leukemia suggests the presence of mechanisms capable of suppression or eradication of CML independent of GVHD.

Acute Disease↗
PubMed1993

Acute graft-versus-host disease prophylaxis with methotrexate and cyclosporine after busulfan and cyclophosphamide in patients with hematologic malignancies.

The combination of two powerful immunosuppressive agents, methotrexate (MTX) and cyclosporine (CSP), has resulted in a significant decrease in the morbidity and mortality after allogeneic bone marrow transplantation (BMT). However, the additive toxicities from ablative preparative regimens may lead to suboptimal use of this combined immunoprophylaxis. We evaluated the efficacy and feasibility of administering MTX/CSP with busulfan (4 mg/kg/d for 4 days) and cyclophosphamide (50 mg/kg/d for 4 days) (BuCy4) in 101 consecutive patients with hematologic malignancies categorized into high- and low-risk groups receiving HLA-matched marrow grafts. Postgrafting immunosuppression consisted of MTX short course (15 mg/m2 on day 1 and 10 mg/m2 on days 3, 6, and 11) and intravenous CSP (1.5 mg/kg every 12 hours). Eighty-three patients (82.1%) received 100% of MTX calculated dose and 87 (86.1%) achieved a CSP therapeutic level (250 to 600 ng/mL) within a median of 16 days. Seventy-three patients (72.2%) received optimal immunosuppressive therapy comprising a full MTX course and achieving CSP therapeutic concentrations. The Kaplan-Meier estimated incidence of grade II to IV acute graft-versus-host disease (GVHD) was 9.2% for all patients and 5.5% in patients receiving optimal GVHD prophylaxis. Eighty-nine patients (88.2%) survived > or = 100 days posttransplant and 43 (48.3%) developed chronic GVHD, the majority of which were de novo (31 of 43). The estimated incidence of relapse was 28.9% for all patients and 14.8% in the low-risk group, with a median follow-up of 24.5 months. High-risk features and the absence of chronic GVHD were significantly associated with relapse (P = .002 and .036, respectively) in multivariate analyses. Projected disease-free survival at 2 years was 52.3% for all patients and 65.2% in low-risk patients. Disease-free survival was significantly improved in optimally treated patients (P = .03) due to a lower incidence of early deaths from acute GVHD and infectious episodes. In conclusion, optimal delivery of MTX/CSP in association with BuCy4 resulted in a near complete abrogation of acute GVHD in HLA-matched transplants and a significantly improved disease-free survival.

Adult↗
PubMed1993

Allogeneic bone marrow transplantation following busulfan-cyclophosphamide with or without etoposide conditioning regimen for patients with acute lymphoblastic leukaemia.

We have investigated the feasibility and efficacy of administering a radiation-free preparative regimen in the setting of allogeneic bone marrow transplantation (BMT) in 40 consecutive patients with acute lymphoblastic leukaemia (ALL). Busulfan (4 mg/kg/d x 4 d) and cyclophosphamide (50 mg/kg/d x 4 d) (BuCy4) were given in 29 patients and 11 received busulfan (4 mg/kg/d x 4 d), etoposide (60 mg/kg) and cyclophosphamide (60 mg/kg/d x 2 d) (BuCy+VP - 16). Median age was 22 years (range 1-50); 11 patients were children < or = 15 years of age. All children and 20 adults were at high risk of relapse pretransplant. Nine adults and one child died from transplant-related toxicity. 11 patients relapsed at a median of 11 months post-transplant (range 2-27). The 3-year Kaplan-Meier estimated probability of relapse was 42.1% and found to be significantly lower in patients with chronic GVHD (P = 0.03). 19 patients are leukaemia-free survivors with a median follow-up of 33 months (range 7-59). The Kaplan-Meier actuarial probability of disease-free survival at 3 years was 43% for all patients. 63.6% for children versus 30.2% for adults (P = 0.24) and 51.6% for patients transplanted in first remission versus 30.2% for those transplanted in subsequent remissions (P = 0.20).

Adolescent↗
PubMed1992

Cytogenic characterization of primary refractory anemia.

Refractory anemia (RA) is the only myelodysplastic syndrome (MDS) devoid of quantitative marrow diagnostic criteria. The diagnosis rests mainly on the subjective identification of qualitative abnormalities according to the French-American-British criteria (FAB) involving one or more bone marrow hematopoietic cell lineages. The occurrence of nonrandom chromosome abnormalities remains the hallmark of the disease and the only means of investigation which confirms the disease objectively. With the purpose in mind to further characterize RA among MDS, we have undertaken a prospective high resolution banding chromosome analyses of bone marrow cells in patients with primary refractory anemia (PRA) with the aim of defining a cytogenetic phenotype and of assessing the clinical relevance of clonal abnormalities at initial diagnosis. Of 39 patients consecutively referred for chromosome analyses with a diagnosis of RA according to the FAB criteria, 27 patients had PRA and fulfilled our criteria for adequate chromosome analyses. Median age was 68 years. Fourteen of 27 patients (52%) had clonal chromosomal abnormalities at diagnosis. None of the patients showed a complex karyotype; 9/14 (64%) had a mixture of normal and abnormal cells. Interstitial or terminal deletions, involving chromosomes 5, 6, 7, 9, 11, 12, and 20, were found in 11/14 (79%) of the patients. Comparison of survival between patients with and without abnormalities showed no difference. The presence of clonal abnormalities did not predict transformation to acute myeloblastic leukemia (AML) nor was it associated with poor survival. In this study, patients with PRA were found to have a predominant pseudodiploid karyotypic pattern characterized by interstitial and/or terminal deletions as opposed to derivatives, specific and non-specific balanced translocations, or other structural and numerical abnormalities. We were unable to reveal any prognostic significance to the presence of these clonal abnormalities at initial diagnosis.

Adult↗
PubMed1989

Chronic B-cell lymphocytosis.

Persistent elevation of lymphocyte counts is usually associated with a malignant monoclonal lymphoproliferative disease. Over the last 8 years, amongst patients investigated in our center for undetermined persistent lymphocytosis, a diagnosis of malignant lymphoproliferation was excluded in 6 cases as studies of surface membrane immunoglobulin light chains showed that they presented a polyclonal expansion of their B-lymphocyte pool. All patients were young-to-middle aged women presenting peculiar immunohematologic findings characterized by 1) persistent (2-7 yr) elevation of lymphocyte counts (4-14 x 10(9)/l), 2) presence of characteristic binucleated B cells on peripheral blood smears, 3) a normal bone marrow histology, 4) a polyclonal increase of serum IgM with low-to-normal IgG and IgA levels. Histologic examination of the spleen in 2 patients and lymph nodes in 1 showed a benign follicular lymphoid hyperplasia. The evolution was benign in every case. We suggest that chronic polyclonal B-cell lymphocytosis is a distinct clinicopathologic entity that should not be confused with malignant lymphoproliferative disorders.

Adult↗
PubMed1988

Bone marrow transplantation for myelodysplastic syndromes.

Eight patients with myelodysplastic syndromes (MDS) were treated with bone marrow transplantation (BMT). Median age was 34.5 years and ranged between 3 and 45. FAB diagnosis was refractory anaemia (RA) in three, RA with excess of blasts (RAEB) in four and RAEB in transformation (RAEB-t) in one case. Four patients were prepared with cyclophosphamide and total body irradiation whilst the other four received busulphan and cyclophosphamide. Engraftment was documented in seven of eight patients. Two patients died from complications related to the procedure. One had early veno-occlusive disease of the liver whilst the other died 46 months after BMT from pulmonary fibrosis. One patient died from recurrent disease 11 months after BMT. Five patients are alive and in complete remission 9-35 months post-transplantation. Four of these patients have a Karnofsky score greater than or equal to 90%. These results suggest that BMT can induce prolonged disease-free survival in patients under 50 years of age. If a compatible donor is available, marrow transplantation should be seriously considered in the treatment of MDS.

Adult↗