Mutations in the gene encoding B1 subunit of H+-ATPase cause renal tubular acidosis with sensorineural deafness.

H+-ATPases are ubiquitous in nature; V-ATPases pump protons against an electrochemical gradient, whereas F-ATPases reverse the process, synthesizing ATP. We demonstrate here that mutations in ATP6B1, encoding the B-subunit of the apical proton pump mediating distal nephron acid secretion, cause distal renal tubular acidosis, a condition characterized by impaired renal acid secretion resulting in metabolic acidosis. Patients with ATP6B1 mutations also have sensorineural hearing loss; consistent with this finding, we demonstrate expression of ATP6B1 in cochlea and endolymphatic sac. Our data, together with the known requirement for active proton secretion to maintain proper endolymph pH, implicate ATP6B1 in endolymph pH homeostasis and in normal auditory function. ATP6B1 is the first member of the H+-ATPase gene family in which mutations are shown to cause human disease.

Hematopoietic stem cell transplantation in severe congenital neutropenia.

BACKGROUND: Severe congenital neutropenia (SCN) is an immunodeficiency characterized by disturbed myelopoiesis and an absolute neutrophil count (ANC) <0.5 × 10(9)/L. SCN is also a premalignant condition; a significant proportion of patients develop myelodysplastic syndrome or leukemia (MDS/L). Allogeneic hematopoietic stem cell transplantation (HSCT) is the only curative treatment for SCN. PROCEDURE: Since 2004, eight HSCT have been performed in seven patients at our center. The indications were transformation to MDS/L (n = 2), granulocyte colony-stimulating factor receptor (CSF3R) mutation(s) (n = 2), granulocyte colony-stimulating factor (G-CSF) resistance (n = 2), and at the patient's own request (n = 1). RESULTS: The mean age at transplantation was 13 years (2.8-28 years) (mean follow-up 32 months, range 21-60). Three patients harbored ELANE mutations, three HAX1 mutations, and in one patient no causative mutation was identified. Two of the ELANE mutations were novel mutations. Three patients initially received myeloablative conditioning and four had reduced intensity conditioning (RIC). Three grafts were from HLA-identical siblings, three from matched unrelated donors and two were cord blood units. Engraftment occurred in all patients. Two of seven (29%) patients died; both had MDS/L and both were among the three that underwent myeloablative conditioning. One patient has chronic GVHD 2 years post-transplant. CONCLUSIONS: The role of HSCT should be explored further in patients with SCN. In particular, the influence of the conditioning regime needs to be evaluated in a larger cohort of patients.

Targeted monitoring of patients at high risk of post-transplant lymphoproliferative disease by quantitative Epstein-Barr virus polymerase chain reaction.

BACKGROUND: Epstein-Barr virus (EBV)-associated post-transplantation lymphoproliferative disease (PTLD) is a serious complication after allogeneic stem cell transplantation (SCT). The likelihood of PTLD is increased in the presence of specific risk factors. Monitoring of EBV DNA load and early administration of rituximab in patients with high EBV loads is recommended for high-risk patients. METHODS: Patients at high risk of EBV-associated PTLD were defined as those showing an EBV serological mismatch between donor and recipient, those with lymphoma, those given cord blood grafts, and those with primary EBV disease before SCT. High-risk patients were prospectively monitored by weekly measurement of EBV DNA by quantitative polymerase chain reaction assay, and rituximab was given when the EBV load reached 10,000 copies/mL or symptoms were suggestive of EBV disease. During the study period (July 2005 to the end of June 2007) 131 patients underwent SCT, of whom 53 had high risk factors. A historical control group transplanted between January 2003 to the end of June 2005 was retrospectively used to evaluate the effect of the prospective monitoring strategy. RESULTS: Of the patients, 30% were positive for EBV DNA at least once; 10% of patients with EBV DNAemia developed PTLD. Risk factors of EBV DNAemia were younger age (P=0.04), receiving transplants from mismatched family or unrelated donors (P=0.01), and acute graft-versus-host disease grades II-IV (P=0.001). The overall frequency of PTLD was 3%; 5.7% in the high-risk group and 1.3% in the standard-risk group. Previous splenectomy (P=0.046) was the only significant risk factor associated with PTLD. In the control group, 6 of 150 patients (4%) developed PTLD; 5/53 (9.4%) in the high-risk group and 1/97 (1%) in the standard-risk group. Human leukocyte antigen-mismatched donors (P<0.01) and EBV-positive donors/EBV-negative recipients (P=0.01) had a significant impact on the risk of PTLD. CONCLUSION: A targeted monitoring strategy among patients at a high risk of EBV-associated PTLD might be helpful to decrease the risk of development of PTLD. However, larger prospective studies are needed to verify this hypothesis.

Safe administration of oral BU twice daily during conditioning for stem cell transplantation in a paediatric population: a comparative study between the standard 4-dose and a 2-dose regimen.

We compared outcome and toxicity in two paediatric groups undergoing SCT and treated with busulphan (BU) by the oral route of administration. One group receiving the standard dose of 1 mg/kg q.i.d. for a total of 16 doses was compared with age- and disease-matched patients receiving 2 mg/kg of BU b.i.d. for a total of eight doses. Seventy-two patients from two Swedish paediatric transplantation centres were included; one centre used a standard q.i.d. administration (n=37) and the second centre used a b.i.d. administration setting (n=35). Our primary objective was to determine the incidence of veno-occlusive disease (VOD), graft-versus-host disease (GVHD), relapse frequency and transplant-related mortality in both cohorts. A total of 17 autologous and 55 allogeneic transplantations was performed for malignant (n=47) and non-malignant (n=25) diseases in the two centres during the period 1990-2005. No significant difference in the incidence of VOD, graft rejection, GVHD, relapse rate or overall survival was observed between the two centres. The clinical outcome of SCT for paediatric patients conditioned with oral BU at a dose of 2 mg/kg for eight doses is comparable to that found for children conditioned using the standard regimen given 1 mg/kg q.i.d. for 16 doses.

BK-viruria and haemorrhagic cystitis are more frequent in allogeneic haematopoietic stem cell transplant patients receiving full conditioning and unrelated-HLA-mismatched grafts.

The influence of conditioning regimen, donor background and HLA matching on development of BK virus (BKV)-associated haemorrhagic cystitis (HC) was examined in 175 allogeneic haematopoietic stem cell transplant (HSCT) patients, undergoing 179 HSCT events. Twenty-seven patients presented late-onset HC, and BK viruria was verified in 23/27 HC events. Seventy-one (40%) HSCTs were performed with myeloablative conditioning (MC), 108 (60%) were performed with reduced intensity conditioning (RIC), 66 (37%) were performed with a related donor (RD) grafts and 113 (63%) with an unrelated donor (URD) graft. BK viruria was more common during HC, than non-HC events, after MC as compared to RIC (both P<0.001), and with an HLA-mismatched donor (P<0.01). By multivariate logistical regression analysis, independent risk factors for HC were BKV (OR 6.7; 95% CI 2.0-21.7; P=0.001), MC (OR 6.0; 95% CI 2.1-17.3; P<0.001) and URD (OR 3.4; 95% CI 1.1-10.6; P=0.03). However, when analysing HSCT performed with URD or RD grafts separately, BKV (OR 8.5; 95% CI 1.8-19.3; P=0.004) and MC (OR 5.9; 95% CI 1.3-11.3; P=0.009) increased the risk for HC only with a URD, but not with an RD graft.

Long-term renal function following bone marrow transplantation.

Renal function, evaluated as glomerular filtration rate (GFR) and effective renal plasma flow (ERPF), was investigated in 187 pediatric patients who underwent allogeneic (n=169) or autologous bone marrow transplantation (BMT). Allogeneic BMT patients were divided into three groups: hematological malignancies, aplastic anemia and non-malignant diseases, whereas autologous patients constituted a fourth group. A total of 64% received total body irradiation (TBI) as conditioning therapy, and 50 healthy children served as controls. GFR and ERPF were normal before transplantation. After 1 year, both GFR and ERPF were significantly reduced. GFR had recovered slightly after 3 years and remained stable thereafter. Recovery in ERPF was not apparent. Renal impairment was found in 41% of patients at 1 year, in 31% at 3 years and in 11% 7 years after BMT. Patients with hematological malignancies had lower GFRs than patients with non-malignant diseases at all time points. The most important risk factor as regards chronic renal impairment was TBI. Type of donor, cyclophosphamide (CY), or acute graft-versus-host disease (GVHD) did not seem to contribute to the development of chronic renal impairment. We suggest that tests of renal function should be included in long-term followup after BMT.

Risk factors for fatal infectious complications developing late after allogeneic stem cell transplantation.

Infectious complications remain a major problem contributing to significant mortality after hematopoietic allogeneic stem cell transplantation (HSCT). Few studies have previously analyzed mortality due to late infections. Forty-four patients dying from an infectious complication were identified from a cohort of 688 consecutive patients surviving more than 6 months without relapse. A control group of 162 patients was selected using the year of HSCT as the matching criterion. Out of 44 patients, 30 (68%) died from pneumonia, 7/44 (16%) from sepsis, 5/44 (11%) from central nervous system infection and 2/44 (4.5%) from disseminated varicella. The cumulative incidences of different types of infection were 1.6% for viral, 1.5% for bacterial and 1.3% for fungal infections and 0.15% for Pneumocystis jirovecii pneumonia. The majority (66%) of the lethal infections occurred within 18 months after HSCT. Acute GVHD (relative risk (RR): 7.19, P<0.0001), chronic GVHD (RR: 6.49, P<0.001), CMV infection (RR: 4.69, P=0.001), mismatched or unrelated donor (RR: 3.86, P=0.004) and TBI (RR: 2.65, P=0.047) were independent risk factors of dying from a late infection. In conclusion, infections occurring later than 6 months after HSCT are important contributors to late non-relapse mortality after HSCT. CMV infection or acute GVHD markedly increase the risk.

Fludarabine-based disease-specific conditioning or conventional myeloablative conditioning in hematopoietic stem cell transplantation for treatment of non-malignant diseases.

Fludarabine-based conditioning (FBC) was given to 24 patients and conventional myeloablative conditioning (MC) to 33 patients, most children, before hematopoietic stem cell transplantation (HSCT) for non-malignant diseases. The donors were human leukocyte antigen (HLA)-A, -B, -DRbeta1-identical related (33%) or unrelated (67%). In the FBC group, two grafts failed versus three in the MC group; all were successfully regrafted. Fever was more common in the MC patients (P=0.003). Bacteremia occurred in 25% of the FBC group and 50% in the MC group (P=0.1). In the FBC group, platelet engraftment was faster and transfusions were fewer (P<0.05). Mucositis and renal function were similar in the two groups. The MC group had higher maximum bilirubin (P=0.03) and less often normal spirometry (P=0.04) after HSCT. A 7-year-old girl in the MC group had permanent alopecia. No patients had severe acute graft-versus-host disease (GVHD). Chronic GVHD was rare. Complete donor CD3+ chimerism was more common in the MC group (P=0.01), but CD33+ engraftment was better with FBS (P=0.03). Treatment-related mortality was 4 and 15%, and 5-year survival was 89 and 85% in the FBC and MC groups. Although survival was similar, FBC is a promising alternative to MC in non-malignant disorders.

Quality of life and health in children following allogeneic SCT.

A total of 52 children, age 9 or over and at least 3 years (median=8) beyond SCT for leukaemia (n=32) or nonmalignant diseases, participated in a single-centre study of health and quality of life (QoL). QoL and self-esteem were assessed with SCHQ-CF87, a generic multidimensional self-report instrument, and with 'I think I am'. As a group, the children had good QoL, but were below norm in the bodily pain (P<0.05), general health and self-esteem dimensions (P<0.01). Lansky or Karnofsky function levels were at a median of 90. Sense of coherence (SOC-13) was normal and correlated with SCHQ-CF87. Most children were subjectively and objectively in good health according to a self-assessment symptom inventory or by a medical record-based scoring of late effects, although pain was commonly reported. A total of 25% of the patients were rated as having moderate to severe late effects, without considering cataracts or infertility. Neither age at SCT, gender, malignant vs nonmalignant disease, nor stature influenced QoL significantly. Children with moderate to severe chronic graft-versus-host disease or cognitive deficits had lower QoL in some dimensions. No correlation was, however, found between the physician-rated total late effects score and overall QoL. Contrarily, QoL was clearly related to the degree of self-rated symptoms.

Adverse health events and late mortality after pediatric allogeneic hematopoietic SCT-two decades of longitudinal follow-up.

Treatment-related late toxicities after pediatric allogeneic hematopoietic SCT (allo-HSCT) are increasingly important as long-term survival has become an expected outcome for many transplanted children and adolescents. In a retrospective cohort study, we assessed long-term health outcomes in 204 allo-HSCT survivors transplanted in childhood or adolescence (<20 years) between 1978 through 2000 after a median follow-up time of 12 (range 4-28) years. Data on conditioning regimen, adverse health events (AE) and growth and hormonal substitutions (hormone replacement therapies (HRTs)) were obtained from medical records. AEs were graded retrospectively according to Common Terminology Criteria for Adverse Events v3.0. Late deaths (⩾48 months after allo-HSCT) were evaluated separately. Multivariate analysis demonstrated that chronic GVHD (P<0.000) and longer follow-up time (P<0.05) correlated with AEs, whereas CY-based conditioning was inversely correlated (P<0.002). TBI and longer follow-up duration predicted more severe AEs (P<0.001 and P<0.001, respectively). HRTs were more frequent after TBI. Diabetes type II, dyslipidemia and hypertension were detected in 9, 7 and 7% of the survivors, respectively. Late deaths (n=22) were most frequently due to pulmonary failure (n=7), followed by secondary malignancy (n=5). The occurrence of AEs after pediatric allo-HSCT is high and likely to increase during extended follow-up, particularly in patients who have received TBI.

Subjective xerostomia in long-term surviving children and adolescents after pediatric bone marrow transplantation.

BACKGROUND: The aim of the present investigation was to evaluate whether the subjective symptoms of dry mouth in long-term-surviving pediatric bone marrow transplant (BMT) patients are associated with low unstimulated salivary secretion rates (USSR) and with stimulated whole salivary secretion rates (SSSR). METHODS: Fifty-three patients surviving > or =2 years after pediatric allogeneic BMT were included. USSR, SSSR, and the change in salivary secretion rates since the previous year were estimated. A questionnaire regarding subjective symptoms of xerostomia was answered. RESULTS: The mean USSR and SSSR were 0.24+/-0.17 and 0.90 +/- 0.58 ml/min, respectively. Salivary gland dysfunction, defined as USSR < or =0.1 ml/min or SSSR < or =0.5 ml/min, was present in 35% of the patients. Seventy-nine percent of the patients expressed one or more symptom of dry mouth, and 49% gave at least two answers indicating dry mouth. The number of complaints increased with age at examination (P<0.05). Both USSR (P<0.01) and SSSR (P<0.01) were inversely correlated to the total number of complaints of xerostomia. A reduction in SSSR compared with the year before was correlated to two or more complaints of xerostomia (P<0.01). The presence of dry mouth at night or on awakening was indicative of both low USSR (P<0.01) and SSSR (P<0.001). Patients reporting dryness during the day had significantly lower SSSR (P<0.05). CONCLUSION: The expression of subjective complaints of xerostomia among long-term surviving pediatric BMT patients is correlated to salivary gland dysfunction and age. It is very important to identify these patients with salivary gland dysfunction to relieve their symptoms and prevent secondary complications.

Successful allogeneic bone marrow transplantation in a 2.5-year-old boy with ongoing cytomegalovirus viremia and severe aplastic anemia after orthotopic liver transplantation for non-A, non-B, non-C hepatitis.

BACKGROUND: A 2.5-year-old boy received a cadaveric orthotopic liver transplant for acute liver failure due to non-A, non-B, non-C hepatitis. After transplantation, he developed thrombocytopenia and neutropenia and subsequently severe aplastic anemia. The patient also suffered from recurrent cytomegalovirus (CMV) viremia, treated with foscarnet and ganciclovir. METHODS: For treatment of his aplastic anemia, the patient underwent an allogeneic bone marrow transplantation from his HLA-identical sister after conditioning with cyclophosphamide at 200 mg/kg and antithymocyte globulin at 3 mg/kg for 5 days. Prophylactic acyclovir was given because of ongoing CMV viremia at the time of bone marrow transplantation. RESULTS: The transplant course was uneventful, with rapid engraftment. There were no signs of liver dysfunction, graft-versus-host disease, or reactivation of CMV. The patient is in excellent health, with normal liver and bone marrow function 3 years after bone marrow transplantation. CONCLUSION: This case report shows that allogeneic bone marrow transplantation is feasible and well tolerated in a patient with severe aplastic anemia after liver transplantation for acute fulminant viral hepatitis.

Does high-dose intravenous immune globulin treatment after bone marrow transplantation increase mortality in veno-occlusive disease of the liver?

Forty-five recipients of bone marrow from HLA-identical siblings were given intravenous immune globulin (IVIG) 0.5 g/kg once a week during the first 3 months after transplantation. Fifty-three consecutive previously transplanted HLA-identical siblings were included as controls. Only patients who were cytomegalovirus (CMV) seropositive or had a CMV-seropositive donor were included. There were no major differences in patient characteristics between the two groups. However, more patients in the IVIG group received individualized graft-versus-host disease (GVHD) prophylaxis with less cyclosporine (P < 0.01), more controls received liposomal amphotericin B (P = 0.01), and more patients in the IVIG group received low-dose heparin as prophylaxis against veno-occlusive disease of the liver (P < 0.001). Median follow-up was 21 months in the IVIG group and 47 months in the control group. There were no differences between the groups with regard to time to engraftment, hospitalization time, or days with fever. No differences between the IVIG group and control group were detected in the incidence of acute GVHD grade II-IV (17% vs. 23%) or chronic GVHD (30% vs. 42%). The incidence of bacterial septicemias (53% vs. 63%) and invasive fungal infections (9% vs. 6%) was unaffected by IVIG treatment. The incidence of symptomatic CMV infection was the same in the two groups (14% vs. 16%). One control patient died of CMV interstitial pneumonitis, and 1 patient from each group died from viral interstitial pneumonitis of other origin. The incidence of veno-occlusive disease (VOD) was 16% in the IVIG group versus 6% in the controls (P = NS). Fatal VOD occurred in 11% of the IVIG group compared with none of the controls (P = 0.02). Other transplant-related complications did not differ between the two groups. Two-year survival was 62% in the IVIG group and 60% in the controls (P = NS). No significant beneficial effect was seen with IVIG, which may increase mortality in VOD. The use of high dose IVIG as prophylaxis in marrow transplant recipients is questioned.

Treatment of hepatic venoocclusive disease with recombinant human tissue plasminogen activator or orthotopic liver transplantation after allogeneic bone marrow transplantation.

Ten allogeneic bone marrow transplant (BMT) recipients with hepatic venoocclusive disease (VOD) were treated with recombinant human tissue plasminogen activator (rt-PA). Two of them subsequently underwent orthotopic liver transplantation (OLT). One additional patient with VOD underwent OLT without prior rt-PA treatment. Treatment with rt-PA was started a median of 14 (1--35) days after BMT. The dose of rt-PA given to adults was 10-50 mg i.v. and that given to children was 3-10 mg i.v. Treatment was given for 2-4 days. In three patients, the dose was administered over a longer period or it was repeated. Four patients responded to rt-PA therapy and six did not. Eight patients suffered from hemorrhages, one intracranial and three gastrointestinal. Four patients required blood transfusions. Four had minor subcutaneous hemorrhages and/or epistaxis. One patient died of intracranial hemorrhage and five from hepatic and/or multiorgan failure. Two patients treated with rt-PA, 10 mg/day for 4 days, are alive; one is alive and well 3 months after BMT, the other has relapsed after 7 months. The three patients undergoing OLT died of chronic hepatic failure, cerebral edema, and pneumonia. Our experience suggests that rt-PA should not be administered in high doses and that the treatment should not be given over a longer period, because of the risk of severe hemorrhages.

Results of different strategies for reducing cytomegalovirus-associated mortality in allogeneic stem cell transplant recipients.

BACKGROUND: Several preventive strategies against cytomegalovirus (CMV) disease have been developed during the last decade. These have frequently been used in combination, and it has been difficult to identify each strategy's contribution. METHODS: Risk factors for CMV disease, death in CMV disease and transplant-related mortality were analyzed in 584 patients, who underwent a total of 594 allogeneic bone marrow transplants. RESULTS: The overall probability of CMV disease was 8.9%. No seronegative patient who had a seronegative marrow donor developed CMV disease. The corresponding probabilities for seronegative patients with seropositive donors, seropositive patients with seronegative donors, and seropositive patients with seropositive donors were 5.4%, 13.7%, and 11.7%, respectively. In multivariate Cox models, the use of preemptive antiviral therapy and being CMV-seronegative reduced the risk for CMV disease, CMV-associated death, and transplant-related mortality (TRM). Patients who received unrelated or mismatched family donor transplants had increased risks for CMV disease, CMV-associated death, and TRM. Older age was a significant risk factor for CMV disease and TRM. A total of 258 patients who were monitored by polymerase chain reaction for CMV DNA were analyzed separately to assess whether addition of another CMV preventive strategy could give benefit. Patients who received mismatched or unrelated donor transplants had increased risk for CMV disease, death in CMV disease, and TRM. High-dose acyclovir prophylaxis or addition of intravenous immune globulin had no influence. CONCLUSIONS: Preemptive therapy based on polymerase chain reaction for CMV DNA was associated with reduced risks for CMV disease, CMV-associated death, and TRM, whereas other prophylactic modalities did not give additional benefit.

Low incidence of acute graft-versus-host disease, using unrelated HLA-A-, HLA-B-, and HLA-DR-compatible donors and conditioning, including anti-T-cell antibodies.

BACKGROUND: Using unrelated bone marrow, there is an increased risk of graft-versus-host disease (GVHD). METHODS: HLA-A-, HLA-B-, and HLA-DR-compatible unrelated bone marrow was given to 132 patients. The diagnoses included chronic myeloid leukemia (n=43), acute lymphoblastic leukemia (n=29), acute myeloid leukemia (n=27), myelodysplastic syndrome (n=4), lymphoma (n=3), myeloma (n=1), myelofibrosis (n=1), severe aplastic anemia (n=12), and metabolic disorders (n=12). The median age was 25 years (range 1-55 years). HLA class I was typed serologically, and class II was typed by polymerase chain reaction using sequence-specific primer pairs. Immunosuppression consisted of antithymocyte globulin or OKT3 for 5 days before transplantation and methotrexate combined with cyclosporine. RESULTS: Engraftment was seen in 127 of 132 patients (96%). Bacteremia occurred in 47%, cytomegalovirus (CMV) infection in 49%, and CMV disease in 8%. The cumulative incidences of acute GVHD > or = grade II and of chronic GVHD were 23% and 50%, respectively. The 5-year transplant-related mortality rate was 39%. The overall 5-year patient survival rate was 49%; in patients with metabolic disorders and severe aplastic anemia, it was 61% and 48%, respectively. The disease-free survival rate was 47% in patients with hematological malignancies in first remission or first chronic phase and 38% in patients with more advanced disease (P=0.04). Acute GVHD was associated with early engraftment of white blood count (P=0.02). Poor outcome in multivariate analysis was associated with acute myeloid leukemia (P=0.01) and CMV disease (P=0.04). CONCLUSION: Using HLA-A-, HLA-B-, and HLA-DR-compatible unrelated bone marrow and immunosuppression with antithymocyte globulin, methotrexate, and cyclosporine, the probability of GVHD was low and survival was favorable.

Unrelated bone marrow transplantation in children: outcome and a comparison with sibling donor grafting.

The clinical course of 59 children, who underwent BMT during 1988-1998 with a matched unrelated donor (MUD), was compared with 59 case controls receiving a sibling donor marrow. Thirty-eight patients had haematological malignancies while 21 had a nonmalignant disorder. The cumulative incidence of acute GVHD grade II-IV was 28% for MUD recipients vs 11% (P = 0.014) for sibling recipients. Extensive chronic GVHD was rare in both groups. The 5-year probability of survival was 52% for MUD vs 77% for sibling recipients (P= 0.014). For children with malignancies the 4-year probability of survival was 52% for MUD vs 67% for sibling recipients with a RFS of 49% vs 62%. In the ALL patients the survival of the MUD recipients was 77% and equalled that of the sibling group. For SAA survival was 43% vs 86% (P = 0.09) and for metabolic disorders 63% vs 89% (P = 0.025). The transplant-related mortality was higher in the MUD group, while death due to relapse was equally distributed. These results of MUD BMT in children compare favourably with most previous reports, and support the use of alternative donors in cases who lack an HLA-identical siblings. Bone Marrow Transplantation (2000).

Graft-versus-leukaemia effect in children: chronic GVHD has a significant impact on relapse and survival.

To examine whether graft-versus-host-disease (GVHD) is associated with a graft-versus-leukaemia (GVL) effect that also influences the outcome of allogeneic stem cell transplantation (SCT) in childhood acute leukaemia, we evaluated all consecutive (n=169) children who had undergone SCT for ALL and AML at our centre. Median follow-up was 7 years. The 5-year probability of chronic GVHD was 34%. Median time to relapse was 24 months in children with chronic GVHD and 6 months in those without. The corresponding 5-year probabilities of relapse were 30 and 45% (P=0.01). The 5-year probability of survival was 54%. Patients with chronic GVHD had a significantly better survival, 77 vs 51% (P=0.01). In a Cox regression model, chronic GVHD independently decreased the risk of relapse (RR 0.44) and further predicted an increased chance of relapse-free survival (RR 1.7) and survival (RR 2.6). The impact of chronic GVHD on survival was most apparent in late-stage disease and in ALL. Acute GVHD was not an independent predictor for relapse or death in this study. This study is in support of a GVL effect in childhood leukaemia related to chronic GVHD, reducing the risk of relapse and improving survival.

Bone marrow transplantation in two children with congenital amegakaryocytic thrombocytopenia.

Two thrombocytopenic infants with essentially normal initial bone marrow morphology were believed to have idiopathic thrombocytopenic purpura. However, they failed to respond to steroids and intravenous immunoglobulins and had a normal platelet recovery after transfusions. The diagnosis was revised to congenital amegakaryocytic thrombocytopenia after bone marrow biopsies, which revealed a marked paucity of megakaryocytes. Repeated biopsies disclosed gradually decreasing numbers of megakaryocytes and increasing marrow hypoplasia. At the ages of 42 and 22 months the children underwent allogeneic bone marrow transplants, one of them with an unrelated marrow donor. Both patients are well with good engraftment of donor marrow and normal peripheral blood counts, 31 and 12 months after BMT, respectively.

Methotrexate combined with cyclosporin A decreases graft-versus-host disease, but increases leukemic relapse compared to monotherapy.

Forty patients with leukemia receiving HLA-identical sibling marrow and treated with four doses of methotrexate (MTX) in combination with cyclosporin A (CSA) for prevention of graft-versus-host disease (GVHD) were compared with retrospective controls consisting of 57 patients treated with MTX alone and 30 patients treated with CSA alone. Follow-up time ranged from 2.6 to 6.7 years after bone marrow transplantation. Patients in the MTX + CSA group were older and received a smaller marrow cell dose, but were otherwise comparable regarding disease status, donor/recipient sex match and seropositivity for cytomegalovirus (CMV) and other herpes viruses. Engraftment was slowest in the MTX + CSA group and fastest in the CSA group (p = 0.005 vs MTX and p less than 0.001 vs CSA). The incidence of moderate to severe acute GVHD (grade II-IV) was 8% among patients on MTX + CSA and 26% and 47% in the MTX (p = 0.028) and CSA (p = 0.0001) groups respectively. The corresponding figures for chronic GVHD were 25, 42 and 40% (n.s.). The incidence of CMV interstitial pneumonia was 0% in patients treated with MTX + CSA compared to 23% in the MTX treated patients (p = 0.01) and 11% in the CSA treated patients (p = 0.05). The actuarial 3-year survival in the three groups was similar, 56% for the MTX + CSA patients and 53% for both the MTX and CSA patients (n.s.).(ABSTRACT TRUNCATED AT 250 WORDS)