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Biomedical subjects

A Oakhill

Publications and source records attributed to A Oakhill.

At least 37 records · Page 2Linked to original sources
PubMed2000

Pediatric marrow transplantation for acute leukemia using unrelated donors and T-replete or -depleted grafts: a case-matched analysis.

A retrospective, case-matched analysis of the short-term toxicity, risk of GVHD and relapse as well as outcome in pediatric unrelated marrow transplantation was conducted by comparing recipients of T-replete and -depleted grafts in a two-center setting. Both groups contained 30 patients with acute leukemia matched by age at transplant, gender, primary diagnosis and disease status. Acute (90% vs 53%) and chronic (48% vs 0%) GVHD were more common among recipients of T-replete grafts. No significant differences in graft rejection/failure or viral infections were encountered between the two groups. Relapses were more prevalent (37% vs 15%) among recipients of T-depleted grafts. Outcome (EFS) was similar in the two groups. Consequently, in the analysis of transplant outcome, the higher risk of procedure-related, toxic complications among pediatric recipients of T-replete marrow grafts appears to be balanced by an increased risk of relapse among the recipients of T-depleted grafts.

Acute Disease↗
PubMed2000

Outcome and clinical course of 100 patients with adenovirus infection following bone marrow transplantation.

We conducted a retrospective review of the clinical features and outcome of adenovirus infection in 572 consecutive patients transplanted in a single centre over a 10 year period. One hundred patients (17%) had a total of 105 episodes of adenovirus infection diagnosed at a median of 18 days post transplant (range 2-150 days). The incidence was higher in children than adults (21% vs 9%, P < 0.001) and in unrelated donor vs matched sibling donor transplants (26% vs 9%, P < 0.001). Diarrhoea and fever were the most common presenting features. Reflecting these symptoms, the most common site of isolation was the stool. Serotypes 1, 2 and 7 were the most frequently seen (total of 41/68 or 60% of evaluable cases). In six patients (6%) adenovirus infection was the direct cause of death occurring at a median of 72 days post transplant (range 18-365 days). Five of these six patients had pulmonary involvement and four had associated graft-versus-host disease (GVHD). Three further patients were considered to have severe adenoviral disease (total incidence 9%). Isolation of virus from multiple sites correlated with a poor outcome (P < 0.001). Comorbid viral infection was common in this group with 50% of all patients having other viruses isolated (predominantly polyoma virus and cytomegalovirus). We conclude that adenovirus is commonly isolated after bone marrow transplant and is a cause of significant morbidity but was a rare cause of mortality (6/572 = 1%) in our patient group as a whole. The relative infrequency of severe infection will make it difficult for the transplant physician to decide which patients should receive experimental antiviral drugs such as ribavirin and cidofovir or immunomodulatory therapy with donor white cell infusions.

Adenovirus Infections, Human↗
PubMed2000

The UK experience in treating relapsed childhood acute lymphoblastic leukaemia: a report on the medical research council UKALLR1 study.

We have examined the toxicity and overall outcome of the Medical Research Council UKALL R1 protocol for 256 patients with relapsed childhood acute lymphoblastic leukaemia (ALL). Second remission was achieved in over 95% of patients. Two patients died during induction and seven patients died of resistant disease. The overall actuarial event-free survival (EFS) at 5 years for all patients experiencing a first relapse was 46% (95% CI 40-52). Duration of first remission, site of relapse, age at diagnosis and sex emerged as factors of prognostic significance. Five-year EFS was only 7% for children relapsing in the bone marrow within 2 years of diagnosis, but was 77% for those relapsing without bone marrow involvement > 2.5 years from diagnosis. All analyses in this report are by treatment received. For those receiving chemotherapy alone, the 5-year EFS was 48%; for autologous bone marrow transplantation (BMT), the 5-year EFS was 47%; for unrelated donor BMT, it was 52%; and for related donor BMT, the 5-year EFS was 45%. The groups, however, were not comparable with respect to risk factor profile, and therefore direct comparison of EFS is misleading. Adjustment for time to transplant and prognostic factors was used to reduce the effects of biases between treatment groups, but did not suggest benefit for any particular treatment. There was failure of our planned randomization scheme in this trial with only 9% of those eligible being randomized, which highlights the difficulties in running randomized trials especially in patients who have relapsed from a previous trial. The optimal treatment for relapsed ALL therefore remains uncertain. Alternative approaches are clearly needed for those with early bone marrow relapse if outcome is to improve.

Antineoplastic Combined Chemotherapy Protocols↗
PubMed2000

Functional analysis of the CD8+CD57+ cell population in normal healthy individuals and matched unrelated T-cell-depleted bone marrow transplant recipients.

The biological activities of CD8+ that co-express CD57 remain poorly defined. It is unclear whether all CD8+ cells have the potential to become CD57+ or whether they represent a unique subset with distinct functions. Several studies have reported the association between elevated numbers of CD8+CD57+ and a wide range of clinical disorders such as viral reactivation of human cytomegalovirus (HCMV). In this study, we have investigated the relationship between viral reactivation and the effect of diminished interleukin (IL)-2 production. Using CD8+ cells isolated from patients at various times after allogeneic transplants and in vitro models of HCMV infection, we determined their combined effect on CD8+CD57+. Our results show that high numbers of CD8+CD57+ correlated with diminished killing of HCMV-infected targets. In addition, we showed a synergistic effect between IL-2 and HCMV in the expansion of CD8+CD57+ cells. Furthermore, these cells after anti-CD3 stimulation did not produce tumour necrosis factor (TNF)-alpha or interferon (IFN)-gamma. Interestingly, IL-10 production was elevated in several patients which appeared to be associated with the time from transplant.

Adolescent↗
PubMed2000

Malignant infantile osteopetrosis presenting with neonatal hypocalcaemia.

Presentation characteristics were reviewed in 14 children from 12 families with malignant infantile osteopetrosis seen at two large referral centres for bone marrow transplantation. Children from six of these families presented initially with symptoms of hypocalcaemia. These comprised early or late neonatal convulsions in six cases (corrected serum calcium < 1.5 mmol/l), and vomiting and irritability (serum calcium 1.68 mmol/l) in another. One other related child had severe and persistent jittering episodes almost certainly attributable to hypocalcaemia. In seven of eight cases, these symptoms developed during the first 14 days of life. Although occasionally reported previously, malignant infantile osteopetrosis remains essentially unrecognised as a cause of neonatal hypocalcaemia, often resulting in diagnostic confusion and delay. This is important in the context of curative haemopoietic stem cell transplantation where preservation of sight may depend on early intervention.

Biomarkers↗
PubMed1999

Children with acute lymphoblastic leukemia who receive T-cell-depleted HLA mismatched marrow allografts from unrelated donors have an increased incidence of primary graft failure but a similar overall transplant outcome.

Disparity for HLA in unrelated donor bone marrow transplantation (BMT) increases the risk of graft rejection and graft-versus-host disease (GVHD) and may compromise transplant outcome. We have compared the outcome of matched and mismatched transplants from unrelated donors in 137 children with acute lymphoblastic leukemia (ALL). Their disease status was complete remission (CR)-1, 24 patients; CR-2, 88 patients; CR-3, 18 patients; CR-4, 2 patients; and relapse, 5 patients. CAMPATH monoclonal antibodies were used for T-cell depletion and cyclosporin A was given to 134 children together with short-course methotrexate in 43, mainly when there was HLA disparity. Fifty-two donor/recipient pairs were HLA-mismatched, 41 at HLA-A and -B and 11 at HLA-DR and -DQ loci. Overall graft failure was increased in recipients of marrow mismatched at either HLA-A, -B, -DR, or -DQ (15.7% v 4.8%; P =.057) mainly because there was a higher proportion of children with primary graft failure (11. 8% v 1.2%; P =.012). The presence of an HLA-C locus mismatch did not independently increase the likelihood of graft failure. There was no significant difference in the incidence of acute GVHD >/= grade 2 between the matched and mismatched groups (P =.849). For patients in CR-2, the risk of relapse post-BMT was significantly lower if leukemic relapse occurred off-treatment (P =.005). The Kaplan-Meier overall and leukemia-free survival (LFS) estimates for recipients of matched and mismatched BMT, respectively, at 36 months were 49% versus 42% (P =.380) and 45% versus 40% (P =.654). Although HLA mismatching results in an increased occurrence of primary graft failure with T-cell-depleted allografts, it allows more donors to be identified rapidly for children with ALL without compromising overall transplant outcome.

Adolescent↗
PubMed1999

FLAG (fludarabine, high-dose cytarabine, and G-CSF) for refractory and high-risk relapsed acute leukemia in children.

BACKGROUND: The treatment of relapsed and refractory leukemia in children remains a challenge. The morbidity of further chemotherapy is considerable, as most patients have already been exposed to intensive multiagent chemotherapy. The FLAG (fludarabine, high-dose cytarabine, and G-CSF) regimen is as intensive but less cardiotoxic because of the avoidance of anthracyclines. PROCEDURE: Nineteen children were treated in two U.K. centers with the FLAG regimen for relapsed and refractory acute myeloid leukemia (AML) and acute lymphoblastic leukemia (ALL). There were 13 males and 6 females, with an age range of 1.9 to 14.2 years. AML was the diagnosis in 12 children, ALL in 4, biphenotypic leukemia in 3. Eight patients had refractory disease, 11 were in relapse (5 in first relapse, 4 in second, and 2 in third). RESULTS: Complete remission was obtained in 13 patients, partial remission was obtained in 4, and 2 patients were considered nonresponders. There were seven patients alive at 12 months (mean) posttherapy; one of these is awaiting bone marrow transplantation (BMT). All patients experienced grade 4 hematological toxicity; no patient died of infection. Thirteen patients received BMT as consolidation (seven unrelated donor; six sibling allografts). Six of these have died, four due to pneumonitis. CONCLUSIONS: FLAG can be regarded as an effective protocol for inducing remission in a group of heavily pretreated children. Its toxicity is acceptable due to the avoidance of anthracyclines.

Adolescent↗
PubMed1999

Role of surgical biopsies in the management of bone marrow transplant patients.

BACKGROUND: Bone marrow transplantation (BMT) patients frequently develop life-threatening problems that have similar clinical presentations but differing aetiologies. Despite intensive investigation by haematological, biochemical, and microbiological means, accurate diagnosis is not always possible. Histological and microbiological examination of biopsies from the affected organ may be indicated to enable an accurate diagnosis to be made in these patients. Here we assess the indications, findings, and outcomes in patients who have required surgical biopsy after BMT. PROCEDURE: We retrospectively reviewed all BMT patients who had surgical biopsies between February 1994 and January 1997. Twenty-six patients (1-46 years, median age 10 years) underwent 40 biopsies from the upper and lower GI tract, lung, or liver. Indications for BMT were: relapsed leukaemia = 18; other types of leukaemia = 3; aplastic anaemia=3; other diseases = 2. Type of BMT: matched related donor = 3, unrelated T-cell depleted donor = 23. RESULTS: Eleven (42%) cases had a change in management; 4 (16%) patients avoided further aggressive therapy because of poor prognosis. Unexpected diagnoses were found in 7 biopsies: 1 acute colitis, 1 duodenal ulcer, 1 liver aspergilloma, 2 transfusion siderosis, 1 radiation fibrosis of the lung, and 1 cytomegalovirus infection of the lung. Three patients were noted to have complications after their procedure. CONCLUSIONS: Surgical biopsies for undiagnosed problems can be of benefit in the management of very sick patients who have received bone marrow transplantations. Despite the fact that these patients are so unwell, there is a low rate of complications related to surgery and anaesthesia.

Adolescent↗
PubMed1999

The outcome of 26 patients with respiratory syncytial virus infection following allogeneic stem cell transplantation.

Respiratory syncytial virus (RSV) is known to cause acute lung injury in the immunocompromised host, especially recipients of bone marrow allografts. Specific prognostic factors for the development of severe life-threatening disease remain to be identified as does the optimum treatment of established disease. Over a 5-year period the incidence and outcome of RSV in BMT recipients was analysed retrospectively. Prognostic factors assessed included type of transplant, engraftment status at the time of infection, the presence of lower respiratory tract disease, viral genotype and treatment received. During the study period, 26 of 336 (6.3%) allogeneic stem-cell recipients were identified as having RSV. Five patients (19.2%) died as a direct result of RSV. One patient died secondary to an intracranial bleed with concomitant RSV. There were four patients with graft failure (two primary and two secondary) attributable to the presence of RSV, two of whom subsequently died of infections related to prolonged myelosuppression. The presence of lower respiratory tract infection and a poor overall outcome was the only statistically significant association. Unrelated donor transplants and AML as the underlying disease appeared to be associated with a poorer outcome. Engraftment status, viral genotype and RSV treatment received did not correlate with outcome. We conclude that future studies are required to identify early sensitive and reproducible prognostic factors of RSV in the immunocompromised host. The roles of intravenous and nebulised ribavirin need to be clarified by prospective controlled trials.

Adolescent↗
PubMed1999

Infections in adults undergoing unrelated donor bone marrow transplantation.

This study retrospectively reviews infections over a 7-year period in 60 consecutive adults (median age 25 years) undergoing their first unrelated donor bone marrow transplant (UD-BMT). T-cell depletion was employed in 93%. More than half the patients had one or more severe, potentially life-threatening, infections. There was a high incidence of invasive fungal infections (Aspergillus 17, Candida four), despite the use of itraconazole or amphotericin prophylaxis. Ten Aspergillus infections occurred beyond 100 d. Two patients (11%) with invasive aspergillosis survived. Clustering of infections was noted, with invasive fungal infections significantly associated with bacteraemias (OR 3.73, P=0.06) and multiple viral infections (OR 4.25, P=0.05). There were 21 severe viral infections in 16 patients, with CMV disease occurring in four patients only; viral pneumonitis was predominantly due to 'community respiratory' viruses. Most early bacteraemias (68%) were due to Gram-positive organisms. The majority of episodes of Gram-negative sepsis were caused by non-fastidious non-fermentative bacteria, such as Pseudomonas spp. and Acinetobacter spp., historically regarded as organisms of low pathogenicity. In patients with successful engraftment and minimal graft-versus-host disease, late infections suggestive of continued immune dysfunction (shingles, recurrent lower respiratory infections, Salmonella enteritis and extensive warts) were common.

Adolescent↗
PubMed1998

Minimal residual disease status before allogeneic bone marrow transplantation is an important determinant of successful outcome for children and adolescents with acute lymphoblastic leukemia.

The efficacy of allografting in acute lymphoblastic leukemia (ALL) is heavily influenced by remission status at the time of transplant. Using polymerase chain reaction (PCR)-based minimal residual disease (MRD) analysis, we have investigated retrospectively the impact of submicroscopic leukemia on outcome in 64 patients receiving allogeneic bone marrow transplantation (BMT) for childhood ALL. Remission BM specimens were taken 6 to 81 days (median, 23) before transplant. All patients received similar conditioning therapy; 50 received grafts from unrelated donors and 14 from related donors. Nineteen patients were transplanted in first complete remission (CR1) and 45 in second or subsequent CR. MRD was analyzed by PCR of Ig or T-cell receptor delta or gamma rearrangements, electrophoresis, and allele-specific oligoprobing. Samples were rated high-level positive (clonal band evident after electrophoresis; sensitivity 10(-2) to 10(-3)), low-level positive (MRD detected only after oligoprobing; sensitivity 10(-3) to 10(-5)), or negative. Excluding 8 patients transplanted in CR2 for isolated extramedullary relapse (all MRD-), MRD was detected at high level in 12 patients, low level in 11, and was undetectable in 33. Two-year event-free survival for these groups was 0%, 36%, and 73%, respectively (P <.001). Follow-up in patients remaining in continuing remission is 20 to 96 months (median, 35). These results suggest that MRD analysis could be used routinely in this setting. This would allow identification of patients with resistant leukemia (who may benefit from innovative BMT protocols) and of those with more responsive disease (who may be candidates for randomized trials of BMT versus modern intensive relapse chemotherapy).

Adolescent↗
PubMed1998

UKCCSG's germ cell tumour (GCT) studies: improving outcome for children with malignant extracranial non-gonadal tumours--carboplatin, etoposide, and bleomycin are effective and less toxic than previous regimens. United Kingdom Children's Cancer Study Group.

BACKGROUND: We report the efficacy and late effects of carboplatin, etoposide, and bleomycin (JEB) for extracranial non-gonadal tumours (GCII, 1989-95) compared with the 5 previous regimens (GCI, 1979-1988) consisting of 3 vincristine, actinomycin, and cyclophosphamide (VAC) and 2 platinum-based protocols. METHODS AND RESULTS: Median follow-up for 52 patients in the GCI study and 46 in GCII was 105 and 48 months, respectively. For GCI, 5- and 10-year actuarial survival was 63% (95% Confidence interval 50 to 75%) or 72% (57 to 83%) if 6 cases given low-dose VAC were excluded. For GCII, 5-year survival was significantly greater at 95% (83 to 99%), p = 0.01. Event-free survival was 46% at 5 years for GCI (33 to 59%) or 52% excluding the low-dose VAC cases (38 to 66%), while for GCII it was 87% (74 to 94%), p = 0.002. Five-year event-free survival of 21 children given cisplatin, etoposide, and bleomycin (BEP) in GCI was 57% (37 to 76%) compared with 87% (74 to 94%) for 46 given JEB in GCII, P = 0.02. Late effects in 30 evaluable survivors of GCI and 43 GCII included renal impairment in 6 in GCI and 0 in GCII and deafness in 11 and 4, respectively. Among 17 survivors of sacrococcygeal tumours treated in GCI, 4 have neuropathic bladder/bowel and another shortening of a leg. In GCII, 4 of 26 have neuropathic bladder/bowel with lower limb weakness in one. CONCLUSIONS: We found JEB to be more effective and less toxic than our previous regimens. Some survivors of sacrococcygeal tumours have neurological late effects.

Adolescent↗
PubMed1998

Second allogeneic bone marrow transplants from unrelated donors for graft failure following initial unrelated donor bone marrow transplantation.

Graft failure is a common and severe complication of unrelated donor bone marrow transplantation (UD-BMT). However, there are few reports of a second UD-BMT in this setting. We describe 12 patients with graft failure (five primary, seven secondary) who had a second transplant, five from their original donor and seven from a different donor. Their median age was 9 years. Two patients died before day 10 of regimen-related toxicity. Nine of 10 evaluable patients engrafted in a median of 17 days. Secondary graft failure was seen in one patient. Transplant-related morbidity was significant. Six of nine developed acute GHVD, there were five severe infections and five patients developed Bearman grade 3 or 4 extramedullary toxicity. Overall, five patients survive at a median of 38 months after the second BMT and two are in continuous complete remission. Second transplants from unrelated donors for graft failure can result in prolonged survival.

Adolescent↗
PubMed1998

Double T cell depletion of bone marrow using sequential positive and negative cell immunoaffinity or CD34+ cell selection followed by Campath-1M; effect on CD34+ cells and progenitor cell recoveries.

An advantage of CD34+ cell selection over antibody purging is that a component allograft is produced comprising a stem cell enriched and an unadsorbed fraction, the latter containing T cells which may be used for post-transplant immunotherapy. Initial reports with PBSC allografts suggested that T cell depletion (TCD) by CD34+ cell selection and post-graft cyclosporin A +/- methotrexate was insufficient prophylaxis against acute GVHD. We compared sequential TCD (of a CD34+ cell-selected fraction) using a second (CD2) immunoaffinity step or Campath-1M monoclonal antibody and complement. Since a high stem cell 'dose' enhances engraftment across HLA barriers and improves overall post-transplant outcome, the recovery of CD34+ cells and progenitors were assessed. Sequential positive (CD34+) and negative (CD2+) immunoaffinity selection resulted in a 3.4 log depletion of T cells as compared to a 4.05 log depletion when CD34+ cell selection was followed by Campath-1M treatment. Recoveries of CD34+ cells, CFU-GM and BFU-E following double depletion using CD34+ cell selection plus CD2+ cell depletion were 28, 25 and 17% as compared to 20, 18 and 16% when CD34+ cells were treated with Campath-1M. The unadsorbed fraction contained 85% of the original T cells, from which donor leukocyte infusions in the range of 10(5) to 10(7) CD3+ cells per kg body weight of the recipient were harvested. Despite the advantages of component allografts, the loss of stem/progenitor cells may restrict sequential TCD steps unless single BM harvests are supplemented and/or replaced with mobilised PBSCs.

Alemtuzumab↗
PubMed1998

Minimal residual disease analysis for the prediction of relapse in children with standard-risk acute lymphoblastic leukaemia.

We report a largely retrospective analysis of minimal residual disease (MRD) in a cohort of 66 children suffering from acute lymphoblastic leukaemia (ALL). All patients lacked high-risk features at diagnosis, i.e. the presenting white cell count was <50 x 10(9)/l, age 1-16 years and translocations t(9;22) and t(4;11) were not present. All were treated according to either the MRC protocols UKALL X or XI. PCR of IgH, TCRdelta and TCRgamma gene rearrangements and allele-specific oligoprobing were employed for the detection of MRD. Sensitivity was at least 10(-4) in 78/82 (93%) probes examined. A total of 33 patients relapsed (seven on therapy and 26 off) and 33 remain in continuing complete remission (CCR) (median follow-up 69 months from diagnosis). Of those who remain in CCR, MRD was present in the bone marrow in 32%, 10% and 0% at 1, 3 and 5 months into therapy respectively. This is in marked contrast to the presence of MRD at these times in 82%, 60% and 41% of patients who relapsed (P<0.001, P<0.005 and P<0.005). These results provide further evidence of a strong correlation between clearance of MRD early in therapy and clinical outcome in childhood ALL.

Adolescent↗
PubMed1998

The outcome of children requiring admission to an intensive care unit following bone marrow transplantation.

We report the results of a retrospective study of the role of intensive care unit (ICU) admission in the management of 367 children who underwent bone marrow transplantation (BMT) at a tertiary referral institution. 39 patients (11%) required 44 ICU admissions for a median of 6 d. 70% received marrow from unrelated donors, half of which were mismatched; 80% had leukaemia and two-thirds were considered high-risk transplants. Respiratory failure was the major reason for admission to ICU. 75% of admissions required mechanical ventilation (for a median of 5 d) and 20 patients had lung injury as defined by the criteria of the Seattle group. None of 11 patients with proven viral pneumonitis survived (P = 0.06) and only one of 20 patients with lung injury survived (P < 0.01). Six of seven patients with a primary neurological problem survived (P < 0.001); these appear to represent a good outcome group. Age, the presence of graft-versus-host disease, the use of inotropes, isolated renal or hepatic impairment, and paediatric risk of mortality (PRISM) score were not predictive of outcome. In total, 12 patients (27% of admissions) survived and were discharged from hospital 30d or more after admission and eight (18%) survived >6 months. ICU admission can be beneficial to selected children post-BMT but it may be less useful in proven viral pneumonitis. Where mechanical ventilation is required, the duration of this support should be limited unless there is rapid improvement.

Acute Disease↗
PubMed1998

Cytomegalovirus infection in recipients of related and unrelated donor bone marrow transplants: no evidence of increased incidence in patients receiving unrelated donor grafts.

Recent reports suggest an increased incidence of cytomegalovirus (CMV) infection in recipients of unrelated donor (UD) bone marrow transplantation (BMT). In this study we have collated the incidence of CMV infection and disease in sequential UD (n = 119) and related donor (RD; n = 79) BMT performed in a single institution over a 7-year period. Low-risk patients (CMV seronegative recipient and donor) accounted for 51% of UD BMT (n = 61) and 62% of RD BMT (n=49), with CMV excretion documented in one RD BMT only. The remaining high-risk patients received identical prophylaxis regimens with aciclovir and intravenous immunoglobulin (IVIG). Two groups consisting of 58 UD BMT (median age 9.0 years, range 0.7-45.3 years) and 30 RD BMT (median age 13.6 years. range 1.6-47.6 years) were analysed. CMV reactivation/re-infection was documented in 15 UD BMT (26%) and 10 RD BMT (33%) (P = 0.72), and CMV disease in four UD BMT (8%) and four RD BMT (13%) (P = 0.533). In this series the risk of CMV excretion and disease following UD BMT was similar to that following RD BMT.

Acyclovir↗