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T N Small

Publications and source records attributed to T N Small.

At least 19 recordsLinked to original sources
PubMed2005

Pre- and post-engraftment bloodstream infection rates and associated mortality in allogeneic hematopoietic stem cell transplant recipients.

We report on bloodstream infection (BSI) rates, risk factors, and outcome in a cohort of 298 adult and pediatric hematopoietic stem cell transplantation (HSCT) recipients at Memorial Sloan-Kettering Hospital from September 1999 through June 2003. Methods. Prospective surveillance study. BSI rates are reported per 10,000 HSCT days. Date of engraftment is defined as the first of at least 3 consecutive dates of absolute neutrophil count >500/mm(3) after stem cell infusion. BSI severity grades: severe (intravenous antibiotics), life threatening (sepsis), or fatal (caused or contributed to death). Results. The incidence of pre- and post-engraftment BSI was 22% and 19.5%, respectively. Pre-engraftment highest rates were observed for viridans streptococci (58), Enterobacteriaceae (39), and Enterococcus faecium (34). Post-engraftment rates ranged from 0.2 to 2.9 without any predominant pathogen. In multivariate analyses, pre-engraftment BSI was associated with diagnosis of chronic myelogenous leukemia, age >18 years and peripheral blood stem cell graft; post-engraftment BSI was associated with acute graft-versus-host disease, neutropenia, and liver or kidney dysfunction. Attributable mortality was 12.5% and 1.7% for pre- and post-engraftment BSI, respectively. BSI fatality rates were 24% for viridans streptococci, 8% for E. faecium, 11% for Staphylococcus aureus, and 67% for Candida. Conclusions. Pre-engraftment BSI, especially by viridans streptococci and E. faecium, was associated with substantial attributable mortality. Post-engraftment BSI was a marker of post-transplant complications and rarely the primary cause of death.

Adolescent↗
PubMed2002

Safe and cost effective use of alteplase for the clearance of occluded central venous access devices.

PURPOSE: To determine whether cryopreserved solutions of the thrombolytic agent alteplase could be used as a safe, effective, and economically reasonable alternative to urokinase in patients presenting with occluded central venous access devices (CVADs). MATERIALS AND METHODS: Alteplase has been reported as an efficacious alternative to urokinase for treatment of occluded CVADs. However, the practicality of using alteplase as the thrombolytic of choice for this indication remained conjectural. To make this approach economically feasible, alteplase was diluted to 1 mg/mL and 2.5-mL aliquots were stored at -20 degrees C until use. A need to confirm that the cryopreserving and thawing of the reconstituted solution did not compromise the safety and efficacy reported from prior trials was recognized. A quality assessment initiative was undertaken to concurrently monitor the safety and efficacy of this approach. Patients presenting with occluded CVADs received a sufficient volume of the thawed alteplase solution to fill the occluded catheter(s). Data, including efficacy, adverse reactions, dwell time, and catheter type, were collected over a 5-month period. RESULTS: One hundred twenty-one patients accounting for 168 attempted clearances were assessable for safety and efficacy. One hundred thirty-six (81%) of the 168 catheter clearance attempts resulted in successful catheter clearance (95% confidence interval, 74% to 86%). No adverse events were reported. CONCLUSION: Cryopreserved 1-mg/mL aliquots of alteplase are safe and effective in the clearance of occluded CVADs when stored at -20 degrees C for 30 days. The ability to cryopreserve alteplase aliquots makes it an economically reasonable alternative to urokinase in the setting of CVAD occlusion.

Adolescent↗
PubMed2002

Respiratory syncytial virus infection following hematopoietic stem cell transplantation.

Respiratory syncytial virus, one of the most common causes of respiratory infections in immunocompetent individuals, is frequently spread to recipients of HSCT by family members, other patients, and health care workers. In immunosuppressed individuals, progression from upper respiratory tract disease to pneumonia is common, and usually fatal if left untreated. We performed a retrospective analysis of RSV infections in recipients of autologous or allogeneic transplants. The incidence of RSV following allogeneic or autologous HSCT was 5.7% and 1.5%, respectively. Of the 58 patients with an RSV infection, 16 of 21 patients identified within the first post-transplant month, developed pneumonia. Seventy-two percent of patients received aerosolized ribavirin and/or RSV-IGIV, including 23 of 25 patients diagnosed with RSV pneumonia. In this aggressively treated patient population, three patients died of RSV disease, each following an unrelated HSCT.

Adolescent↗
PubMed2001

Lung transplantation after allogeneic marrow transplantation in pediatric patients: the Memorial Sloan-Kettering experience.

BACKGROUND: Chronic lung disease and pulmonary failure are complications that can occur after bone marrow transplantation (BMT) and are associated with severe morbidity and mortality. METHODS: We report on four patients who developed chronic, progressive, and irreversible lung disease 1 to 3 years after allogeneic BMT in childhood. These patients had chronic graft-versus-host disease (n=3) or radiation-related pulmonary fibrosis (n=1). Three patients underwent double lung transplants and one patient underwent a single lung transplant 2 to 14 years after BMT. RESULTS: All four patients tolerated the lung transplantation procedure well and showed significant clinical improvement with normalization of pulmonary function tests by 1 year posttransplant. One patient died from infectious complications 3 years after lung transplantation, and one patient died after chronic rejection of the transplanted lungs 6 years posttransplant. Two patients remain alive without significant respiratory impairment 2 and 7 years after lung transplantation. CONCLUSION: We conclude that lung transplantation offers a viable therapeutic option for patients who develop respiratory failure secondary to BMT.

Adolescent↗
PubMed2000

Disseminated toxoplasmosis following T cell-depleted related and unrelated bone marrow transplantation.

More than 95% of reported cases of disseminated toxoplasmosis following BMT have occurred following an unmodified transplant. Most have been fatal, diagnosed at autopsy and without antemortem institution of specific therapy. From 1989 to 1999, we identified 10 cases of disseminated toxoplasmosis, in 463 consecutive recipients of a T cell-depleted (TCD) BMT. Transplants were from an unrelated donor (n = 5), an HLA-matched sibling (n = 4) or an HLA-mismatched father (n = 1). In 40%, both the donor and recipient had positive IgG titers against T. gondii pre-transplant; in 30%, only the recipient was sero-positive. Three recipients of an unrelated TCD BMT developed toxoplasmosis despite both donor and host testing negative pretransplant. All 10 patients presented with high grade fever. CNS involvement ultimately occurred in seven patients, with refractory respiratory failure and hypotension developing in nine. Eight of 10 cases were found only at autopsy, involving the lungs (n = 7), heart (n = 5), GI tract (n = 5), brain (n = 8), liver and/or spleen (n = 5). The only survivor, treated on the day of presentation with fever and headache, was diagnosed by detection of T. gondii DNA by polymerase chain reaction (PCR) performed on the blood and spinal fluid. This study demonstrates the similar incidence of toxoplasmosis following TCD BMT and that reported post T cell-replete BMT, and underscores the need for rapid diagnostic tests in an effort to improve outcome.

Adult↗
PubMed2000

Stem cell transplantation for the treatment of Fanconi anaemia using a fludarabine-based cytoreductive regimen and T-cell-depleted related HLA-mismatched peripheral blood stem cell grafts.

We have employed a new cytoreductive regimen to transplant two patients with Fanconi anaemia (FA), using T cell-depleted two HLA-allele disparate related peripheral blood stem cell transplants (PBSCTs). Patient 1, a 5-year-old male with FA and aplastic anaemia, initially received an HLA two-antigen mismatched unrelated cord blood transplant and failed to engraft. He received fludarabine (Flu) and cyclophosphamide (Cy), followed by a CD34(+) E-rosette(-) (CD34(+)E(-)), T cell-depleted, granulocyte colony-stimulating factor (G-CSF)-mobilized PBSCT from his HLA B-DRB1 mismatched father. He received anti-thymocyte globulin (ATG), steroids, FK506 and G-CSF after transplant for rejection and graft-versus-host disease (GVHD) prophylaxis. The patient is now 23 months after SCT with no evidence of GVHD and with full haematopoietic and immune reconstitution. Patient 2, a 10-year-old boy with FA and myelodysplastic syndrome, received single-dose total body irradiation (SDTBI), Flu and Cy followed by a CD34(+)E(-), T-cell-depleted, G-CSF-mobilized PBSCT from his HLA B-DRB1 mismatched sister. He also received ATG, steroids, FK506 and G-CSF after transplant. The patient is now 12 months after SCT in complete remission with no evidence of GVHD. Absolute neutrophil counts (ANC) of > 1 x 10(9)/l were achieved on day 11 and day 10 post transplant respectively. Both patients are fully engrafted. In summary, we report two successful T-cell-depleted stem cell transplants from mismatched related donors for the treatment of Fanconi anaemia, using a fludarabine-based cytoreduction. Both patients experienced minimal toxicity, rapid engraftment and no GVHD.

Child, Preschool↗
PubMed1999

Comparison of immune reconstitution after unrelated and related T-cell-depleted bone marrow transplantation: effect of patient age and donor leukocyte infusions.

Unrelated bone marrow transplantation (BMT) is often complicated by fatal opportunistic infections. To evaluate features unique to immune reconstitution after unrelated BMT, the lymphoid phenotype, in vitro function, and life-threatening opportunistic infections after unrelated and related T-cell-depleted (TCD) BMT were analyzed longitudinally and compared. The effects of posttransplant donor leukocyte infusions to treat or prevent cytomegalovirus (CMV) or Epstein-Barr virus (EBV) infections on immune reconstitution were also analyzed. This study demonstrates that adult recipients of TCD unrelated BMTs experience prolonged and profound deficiencies of CD3(+), CD4(+), and CD8(+) T-cell populations when compared with pediatric recipients of unrelated BMT and adults after related BMT (P <.01), that these adults have a significantly increased risk of life-threatening opportunistic infections, and that the rate of recovery of CD4 T cells correlates with the risk of developing these infections. Recovery of normal numbers of CD3(+), CD8(+), and CD4(+) T-cell populations is similar in children after related or unrelated BMT. This study also demonstrates that adoptive immunotherapy with small numbers of unirradiated donor leukocytes can be associated with rapid restoration of CD3(+), CD4(+), and CD8(+) T-cell numbers, antigen-specific T-cell responses, and resolution of CMV- and EBV-associated disease after unrelated TCD BMT.

Adolescent↗
PubMed1999

Posterior leukoencephalopathy syndrome may not be reversible.

The association of an acute reversible encephalopathy with transient occipital lobe abnormalities on imaging studies is well known. This condition has been called reversible posterior leukoencephalopathy syndrome. The clinical presentation usually includes seizures, headache, altered mental status, and blindness, often associated with hypertension and immunosuppressants. The authors discuss a two-year-old male with Down syndrome who presented 2 months after allogeneic bone marrow transplantation with severe oculogyric crisis, without other complaints. The patient was being treated for hypertension and was receiving cyclosporine for prophylaxis of graft-vs-host disease. A computed tomography scan of the head revealed marked bilateral lucencies mainly involving the white matter of the occipital lobes, with a few foci of punctate hemorrhage. The condition improved when cyclosporine was discontinued, but an area of leukomalacia was identified on follow-up magnetic resonance imaging. To the authors' knowledge, oculogyric crisis as a presentation of reversible posterior leukoencephalopathy has not been previously described. Recognizing this association is important, because patients receiving cyclosporine are often receiving other medications that can potentially cause dystonic eye movements, possibly leading to a delay in diagnosis and treatment, which can result in an irreversible neurologic deficit.

Bone Marrow Transplantation↗
PubMed1999

Allogeneic bone marrow transplantation versus chemotherapy for the treatment of childhood acute lymphoblastic leukemia in second remission: a single-institution study.

PURPOSE: A retrospective analysis of the treatment of childhood acute lymphoblastic leukemia (ALL) in second remission (CR2) was undertaken at our institution to compare the outcome and prognostic factors of patients treated with chemotherapy or allogeneic bone marrow transplantation (BMT). PATIENTS AND METHODS: Seventy-five children who suffered a medullary relapse and achieved a second remission were treated with either an unmodified allogeneic HLA-matched sibling BMT after hyperfractionated total body irradiation (TBI) and cyclophosphamide (n = 38) or chemotherapy according to institutional chemotherapy protocols (n = 37). To avoid the bias of survival from the attainment of second remission in favor of BMT, the final comparative statistical analysis used the landmark approach and comprised 37 and 29 patients from the BMT and chemotherapy groups, respectively RESULTS: The disease-free survival (DFS) rate was 62% and 26% at 5 years, respectively, for the BMT and the chemotherapy groups (P = .03), with relapse rates of 19% and 67%, respectively, for these two groups (P = .01). There was an overall advantage for the BMT therapeutic approach, as compared with chemotherapy, for patients with ALL in CR2 (1) for patients with a WBC count (at diagnosis) of 20 x 10(9)/L or higher (DFS, 40% v 0%) and those with a WBC count of less than 20 x 10(9)/L (DFS, 73% v35%), (2) for patients whose duration of CR1 was less than 24 months (DFS 48% v 9%) and for patients whose duration of CR1 was 24 months or longer (DFS, 81% v 37%) and (3) for patients who were initially treated with intensive regimens incorporating more than five chemotherapy agents (DFS, 57% v 20%) and for patients treated with five agents or fewer (DFS, 72% v 32%). CONCLUSION: In our single-institution series, unmodified HLA-matched allogeneic sibling transplants using hyperfractionated TBI and cyclophosphamide for patients with ALL in CR2 have resulted in superior outcome with a significantly improved probability of DFS and a lower relapse rate, as compared with those for patients treated with chemotherapy, regardless of the duration of first remission, the disease characteristics at diagnosis, or the intensity of prior treatment during first remission.

Antineoplastic Agents↗
PubMed1998

T-cell-depleted allogeneic bone marrow transplantation as postremission therapy for acute myelogenous leukemia: freedom from relapse in the absence of graft-versus-host disease.

Thirty-one consecutive patients with acute myelogenous leukemia (AML) in first complete remission and 8 with AML in second complete remission received T cell-depleted allogeneic bone marrow transplants from HLA-identical sibling donors. Patients received myeloablative cytoreduction consisting of hyperfractionated total body irradiation, thiotepa, and cyclophosphamide. Those patients at risk for immune-mediated graft rejection received additional immune suppression with antithymocyte globulin and methylprednisolone in the early peritransplant period. Patients with AML who underwent allogeneic T-cell-depleted bone marrow transplantations (BMT) in first or second remission have achieved respective disease-free survival (DFS) probabilities of 77% (median follow-up at approximately 56 months) and 50% (median follow-up at approximately 48 months). Ten of 31 patients transplanted in first remission were > or = 40 years old and have attained a DFS at 4 years of 70%. For patients with AML transplanted in first or second remission, the respective cause-specific probabilities of relapse were 3.2% or 12.5%, and those of nonleukemic mortality were 19.4% or 37.5%. There were no cases of immune-mediated graft rejection and no cases of grade II to IV acute graft-versus-host disease (GVHD). All survivors enjoy Karnofsky performance scores (KPS) of 100%, except 2 patients with KPS of 80% to 90%. T-cell-depleted allogeneic BMT can provide durable DFS together with an excellent performance status in the majority of patients with de novo AML. In addition, GVHD is not an obligatory correlate of the graft-versus-leukemia benefit or freedom from relapse afforded by allogeneic BMT administered as postremission therapy for AML. This study provides a basis for prospective comparison with other postremission therapies considered standard in the management of patients with this disease.

Adolescent↗
PubMed1998

High-dose induction chemoradiotherapy followed by autologous bone marrow transplantation as consolidation therapy in rhabdomyosarcoma, extraosseous Ewing's sarcoma, and undifferentiated sarcoma.

PURPOSE: To improve response and survival rates in patients with high-risk rhabdomyosarcoma (RMS), extraosseous Ewing's sarcoma, and undifferentiated sarcoma, we used a short course of induction with multi-agent chemotherapy, hyperfractionated radiotherapy, and surgery when possible. Consolidation was with intensive chemotherapy and autologous bone marrow transplantation (ABMT). PATIENTS AND METHODS: Twenty-six patients (21 with RMS, three with undifferentiated sarcoma, and two with extraosseous Ewing's sarcoma) were entered onto the protocol between June 1990 and March 1994. Induction consisted of ifosfamide, etoposide, doxorubicin, dactinomycin, cyclophosphomide, and vincristine, and a split course of hyperfractionated radiotherapy. Patients who attained a complete response (CR) or good partial response (GPR) received consolidation with high-dose melphalan and etoposide followed by ABMT. RESULTS: Of 26 previously untreated patients 19 (73%) achieved a CR (n=13) or GPR (n=6) at the completion of induction and underwent ABMT. Two-year overall survival (OS) was 56% (95% confidence interval [CI], 36% to 76%) and progression-free survival (PFS) was 53% for the whole group (95% CI, 33% to 73%). CONCLUSION: Consolidation of response by myeloablative chemotherapy was well tolerated. Split-course hyperfractionated radiotherapy did not increase the rate of local control. The results of this short-course therapy were comparable to previous therapies of 1 to 2 years' duration. Induction and consolidation chemotherapy, as well as radiation dose, could be further intensified, since no death due to toxicity occurred among these patients.

Adolescent↗
PubMed1997

Mutation analysis of IL2RG in human X-linked severe combined immunodeficiency.

Severe combined immunodeficiency (SCID) is a syndrome of profoundly impaired cellular and humoral immunity. In humans, SCID is most commonly caused by mutations in the X-linked gene IL2RG, which encodes the common gamma chain, gamma c, of the leukocyte receptors for interleukin-2 and multiple other cytokines. To investigate the frequency and variety of IL2RG mutations that cause SCID, we analyzed DNA, RNA, and B-cell lines from a total of 103 unrelated SCID-affected males and their relatives using a combination of molecular and immunologic techniques. Sixty-two different mutations spanning all eight IL2RG exons were found in 87 cases, making possible correlations between mutation type and functional consequences. Although skewed maternal X chromosome inactivation, single-strand conformation polymorphism, mRNA expression, and cell surface staining with anti-gamma c antibodies were all helpful in establishing IL2RG defects as the cause of SCID, only dideoxy fingerprinting and DNA sequence determination each detected 100% of the IL2RG mutations in our series. Abnormal gamma c chains may be expressed in the lymphocytes of as many as two thirds of patients with X-linked SCID. Specific mutation diagnosis thus remains technically challenging, but it is important for genetic counseling and perhaps for helping to select appropriate subjects for retroviral gene therapy trials, This is a US government work. There are no restrictions on its use.

DNA Fingerprinting↗
PubMed1997

Risk of extramedullary relapse following allogeneic bone marrow transplantation for acute myelogenous leukemia with leukemia cutis.

Leukemia cutis (LC) is a rare feature of acute myeloblastic leukemia (AML). Little information is available regarding its prognostic influence on post-transplant outcome. In our institution, 202 patients with AML received an allogeneic HLA-identical marrow transplant from related donors between March 1982 and January 1994. Thirteen patients had prior leukemic involvement of the skin (leukemia cutis or LC group) while 189 patients did not (non-LC group). There was a higher incidence of patients with the M4-M5 FAB subtypes in the LC group (83%) as compared to the non-LC group (33%). In addition, the percentage of patients transplanted in relapse was also higher in the LC group (69 vs 15%). While there were no differences observed in the rates of relapse post-transplant in the LC and non-LC groups when matched for stage of disease at transplant, the sites of relapse differed markedly. Five of six relapses in the LC group involved extramedullary sites as compared to only six of 38 relapses in the non-LC group (P = 0.002), with a 6-year probability of extramedullary relapse of 38.5% in the LC group as compared to 3.9% in the non-LC group. This increased probability of extramedullary relapse was independent of the FAB morphology (50 vs 2% for patients with the M4-M5 subtypes in the LC and the non-LC group respectively) and of disease status at the time of transplant. Moreover, only three relapses post-transplant involved the skin, all of which were in the LC group, with a probability of skin relapse of 23.1% in this group. Patients with AML and leukemia cutis have a remarkable propensity to relapse in extramedullary sites following marrow transplantation. These relapses occur in the skin as well as other organs. Further investigations are needed to understand the biological basis of this clinical feature.

Adult↗
PubMed1997

Biology and adoptive cell therapy of Epstein-Barr virus-associated lymphoproliferative disorders in recipients of marrow allografts.

Epstein-Barr virus (EBV) is an ubiquitous herpesvirus which is carried as a latent infection of B lymphocytes and salivary gland epithelial cells in over 90% of normal adults. Latently infected EBV-transformed B cells circulate at low frequency in the blood for the life of the host. These transformed B cells stimulate a heterogeneous and complex host cell response, ultimately leading to the development and maintenance of high frequencies of HLA-restricted T cells specific for the EBV-encoded nuclear antigens EBNA2-EBNA6 and the latency membrane proteins LMP-1 and LMP-2. Responses to latent EBV-encoded proteins are hierarchical with responses to certain epitopes predominating, dependent upon the HLA genotype of the host. Profound suppression of T-cell immunity may permit the emergence of polyclonal, oligoclonal or monoclonal EBV antigen-expressing lymphoproliferative disorders or malignant B-cell lymphomas expressing these latent EBV antigens. Adoptive transfer of small numbers of peripheral blood mononuclear cells or HLA-partially matched T cells from in vitro expanded EBV-specific T-cell lines derived from a seropositive marrow donor has induced durable regressions of bulky, widely metastatic monoclonal EBV lymphomas in a high proportion of cases. This review describes the current state of knowledge and hypothesis regarding the biology and immunology of EBV infection in the normal host, the features of donor, host and virus which contribute to the development of EBV-associated lymphoproliferative diseases and the mechanisms whereby they are controlled by adoptive transfer of immune T cells.

Bone Marrow Transplantation↗
PubMed1997

Comparison of long-term outcome of children with severe aplastic anemia treated with immunosuppression versus bone marrow transplantation.

Children with severe aplastic anemia (SAA) are treated with bone marrow transplantation (BMT) if a human leukocyte antigen (HLA) compatible sibling donor is available, or alternatively with immunosuppressive therapy (IST). Three retrospective trials examining BMT vs IST in pediatric patients treated from 1970-1988 found BMT resulted in a superior survival rate. Advances have been made in general supportive care and in the approach to each of these treatment modalities in the last decade. To compare survival following BMT and IST in a more recent era, we retrospectively analyzed the results of 48 consecutively treated children with SAA presenting to Memorial Sloan-Kettering Cancer Center (MSKCC) between 1983 and 1992. In contrast to the previous studies, the estimated survival of the BMT and IST groups at 120 months are equivalent, 75.6% and 73.8%, respectively. The IST results in our series are superior to the 42-48% (2-10 year) survival previously published, but similar to survival data observed in more recent IST trials employing more intensive immunosuppression (antithymocyte globulin and cyclosporine). The overall BMT survival rates are similar to those previously published, although BMT results improved dramatically during the latter five years of this analysis, with all 11 patients transplanted surviving with a minimum follow-up of 3 years. No surviving BMT patient has extensive chronic graft-versus-host disease (GvHD), a major cause of long-term mortality post-BMT. Therefore, it is likely the BMT survival curve will remain stable. In contrast, the survival curve of the IST patients is likely unstable, since patients are still at risk for relapse or development of clonal disease. Thus, despite overall similar survival rates, we continue to recommend BMT as first-line therapy in pediatric SAA patients with matched sibling donors.

Adolescent↗