Prevalence and clinical implications of bone marrow involvement in pediatric anaplastic large cell lymphoma.

Anaplastic large cell lymphoma (ALCL) harbors the reciprocal chromosomal translocation t(2;5)(p23;q35) in approximately 80% of the cases. The genes involved are nucleophosmin (NPM) and anaplastic lymphoma kinase (ALK) and the resulting chimeric NPM-ALK protein is thought to play a key role in the pathogenesis of t(2;5) positive ALCL. Few data on bone marrow (BM) involvement in ALCL have been published and they mostly rely on morphological examination of BM smears. We studied 52 ALCL for NPM-ALK expression by RT-PCR: 47/52 biopsies were positive. In 41 of the 47 cases we obtained the BM at diagnosis and investigated the prevalence of minimal BM infiltration by RT-PCR and real-time PCR. Minimal disseminated disease was positive in 25/41 patients (61%), of whom six had morphologically infiltrated BM. Survival analysis demonstrated a 5-year progression-free survival of 41 +/- 11% for patients with molecularly positive BM vs 100% for patients with negative BM (P = 0.001). These results suggest that minimal BM involvement at diagnosis is a common event in pediatric ALCL and that minimal BM disease monitoring could identify patients at risk of relapse.

Unrelated bone marrow transplantation for high-risk anaplastic large cell lymphoma in pediatric patients: a single center case series.

OBJECTIVES: The use of allogeneic stem cell transplantation in NHL patients is not yet clearly defined, especially in children and adolescents, but this option offers the advantages of a tumor-free graft and the possible induction of a graft-vs.-tumor effect. PATIENTS AND METHODS: We report the results of four consecutive pediatric patients affected by anaplastic large cell lymphoma (ALCL) and treated with allogeneic stem cell transplantation from an unrelated donor. The conditioning regimen was based on total body irradiation given in association with etoposide in three patients, and with thiotepa and cyclophoshamide in one patient. Graft-vs.-host disease (GVHD) prophylaxis consisted of cyclosporin, a short course of methotrexate and rabbit antithymocyte globulin. RESULTS: All patients had rapid engraftment within 3-4 wk for neutrophils and platelets, and achieved a stable full donor chimerism that has been maintained to the last follow-up visit. One patient later developed a restrictive pneumonopathy. This patient had been heavily pretreated during the course of the disease having suffered four relapses and had received a cumulative dose of bleomycin of 160 mg/m(2). After a follow-up of 11-42 months, all patients are alive in complete hematological and molecular remission; and three of them without any chronic GVHD. CONCLUSIONS: The increasing number of volunteer bone marrow donors and the reduced toxicity of unrelated stem cell transplantation, especially in children, make this therapeutic option worth more extensive investigation in the treatment of high-risk failure ALCL, although more data is needed to evaluate the long-term benefits. In this regard, the presence of factors predictive of worst outcome such as an early relapse (within 12 months from diagnosis), a refractory or relapsing ALCL and the persistent detection on blood or bone marrow of nucleophosmin-anaplastic lymphoma kinase protein (NPM-ALK) transcript may help select the patients eligible to allogeneic related or unrelated stem cell transplantation.

Normal thrombopoietin and its receptor (c-mpl) genes in children with essential thrombocythemia.

BACKGROUND: Following the observation of thrombopoietin (TPO) gene abnormalities as the cause of familiar cases of thrombocythemia similar derangements of TPO and/or its receptor (c-mpl) might be surmised to be at the root of increased platelet count also in non-familiar (sporadic) cases. Although this was not demonstrated in adults, little data exist about childhood. PROCEDURES: We studied the molecular biology of TPO and c-mpl in seven children with non-familiar essential thrombocythemia (ET) and one child with secondary thrombocytosis (ST). Plasma TPO content was measured using a commercially available kit. Genomic DNA was extracted from whole blood by standard methods and TPO and c-mpl genes were amplified by polymerase chain reaction (PCR) and sequenced. RESULTS: Plasma TPO levels were normal in all our patients. No alteration was detected in either coding region, including the flanking intronic sequences of TPO and c-mpl genes. As compared to the published normal sequence of the TPO gene, one allelic base change in a non-coding region of intron 1 was found in all children with ET and ST, but this was reported as a common finding in normal subjects as well. CONCLUSIONS: High platelet count in our series of sporadic ET of childhood is not due to an abnormality either of TPO or c-mpl gene.

Incidence and treatment of hemorrhagic cystitis in children given hematopoietic stem cell transplantation: a survey from the Italian association of pediatric hematology oncology-bone marrow transplantation group.

The purpose of this multicenter study was to assess the incidence and the treatment of hemorrhagic cystitis (HC) in 1218 pediatric patients, with a mean age of 10.8 years, who underwent hematopoietic stem cell transplantation (HSCT). In all, 44 patients (3.6%) developed HC a median 23 days after HSCT. The incidence of HC was higher in allogeneic than in autologous HSCT recipients (P=0.0001). Of the 44 patients, 37 (84%) recovered from HC in a median 30 days (range 3-100); the other seven children died while still suffering from HC. Hyperbaric oxygen therapy (HOT) achieved significantly better results than prostaglandin therapy (P=0.02) in the treatment of grade II-III HC. By multivariate analysis, age <96 months and allogeneic HSCT were significantly associated with the occurrence of HC: P=0.008 and 0.013, respectively. After a median follow-up of 5.75 years, the 5-year survival of patients who did or did not develop HC was: 43 vs 52%, P=0.03, respectively. This study indicates that age and type of HSCT are factors predisposing to HC in children given HSCT and demonstrates the promising role of HOT in a conservative approach to HC treatment.

Prospective analysis of minimal bone marrow infiltration in pediatric Burkitt's lymphomas by long-distance polymerase chain reaction for t(8;14)(q24;q32).

The chromosomal translocation t(8;14)(q24;q32) represents a characteristic marker for Burkitt's lymphoma (BL). This translocation involves the MYC oncogene on chromosome 8 and the immunoglobulin heavy-chain (IgH) locus on chromosome 14. Since the translocation does not produce a fusion gene, we established a long-distance polymerase chain reaction (LD-PCR) assay that can detect the t(8;14) at the genomic level. The sensitivity of the LD-PCR was 10(-4). We used the LD-PCR assay to prospectively study 78 BL patients and found a specific PCR product in 52 of them. Among the 52 positive patients, we could test both the tumor and the bone marrow (BM) at diagnosis in 33 and determined the prevalence of minimal disseminated disease (MDD) at diagnosis. In 12/33 patients, BM was positive by LD-PCR and in 10 of them we conducted a study of minimal residual disease (MRD). Eight out of 10 children showed a clearance of MRD after one cycle of chemotherapy. The only two patients who did not achieve a negative MRD status died of disease progression. The comparative analysis of sensitivity of BM aspirate, BM biopsy and LD-PCR in t(8;14)-positive patients demonstrated a superiority of the molecular method in the assessment of MDD. The LD-PCR for t(8;14) is an important tool to study minimal BM infiltration at diagnosis and to determine its response kinetics in BL.

Successful unrelated bone marrow transplantation for Shwachman-Diamond syndrome.

A 5-year-old boy with Shwachman-Diamond syndrome underwent unrelated HLA-identical bone marrow transplantation for severe pancytopenia. Conditioning was with busulfan, thiotepa and cyclophosphamide plus rabbit anti-lymphocyte serum. Engraftment for neutrophils and platelets was observed on days +18 and +41, respectively. Transplant-related side-effects were mild and transient. After a follow-up of 32 months, the patient is alive and enjoys a normal life, off any immunosuppressives. Immunological and hematological reconstitution is complete while other phenotypic characteristics (pancreatic insufficiency, short stature, femur dysostosis) are stable. Although experience in this field is scarce, we speculate that bone marrow failure in Shwachman-Diamond syndrome (even if not linked to the appearance of clonal disorders or leukemic transformation) is an indication for bone marrow transplantation and may be associated with a better outcome.

Risk management of HBsAg or anti-HCV positive healthcare workers in hospital.

Recommendations are made for controlling the transmission of the hepatitis B and hepatitis C viruses from healthcare workers to patients. These recommendations were based both on the literature and on experts' opinions, obtained during a Consensus Conference. The quality of the published information and of the experts' opinions was classified into 6 levels, based on the source of the information. The recommendations can be summarised as follows: all healthcare workers must undergo hepatitis B virus vaccination and adopt the standard measures for infection control in hospitals; healthcare workers who directly perform invasive procedures must undergo serological testing and the evaluation of markers of viral infection. Those found to be positive for: 1) HBsAg and HBeAg, 2) HBsAg and hepatitis B virus DNA, or 3) anti-hepatitis C virus and hepatitis C virus RNA must abstain from directly performing invasive procedures; no other limitations in their activities are necessary. Infected healthcare workers are urged to inform their patients of their infectious status, although this is left to the discretion of the healthcare worker; whose privacy is guaranteed by law. If exposure to hepatitis B virus occurs, the healthcare worker must undergo prophylaxis with specific immunoglobulins, in addition to vaccination.

Saccharomyces cerevisiae fungemia in a neutropenic patient treated with Saccharomyces boulardii.

A case of Saccharomyces fungemia in an 8-month-old baby affected by acute myeloid leukemia while receiving intensive chemotherapy is reported. The patient was receiving prophylaxis treatment with Saccharomyces boulardii capsules (Codex) to prevent diarrhea, which is commonly associated with this type of chemotherapy. Fever spiked just the day after ending the chemotherapy course, and a strain of Saccharomyces cerevisiae was isolated from blood culture although the patient was also receiving antifungal prophylaxis with fluconazole. The patient recovered, though still neutropenic, with amphotericin-B and removal of the central venous catheter. The common biochemical characteristics make it difficult to differentiate between the strain of Saccharomyces cerevisiae and that of Saccharomyces boulardii with routine methods. In other cases, authors demonstrated an identity between the two strains with a more detailed analysis. These reports raise concern about the potential side effects of such biotherapeutic agents.

[Peripheral blood stem cell collection in pediatric oncohematology. Experience with patients weighing less than 15 kg]. / Raccolta di cellule staminali periferiche in oncoematologia pediatrica. Esperienza su soggetti di peso inferiore a 15 kg.

BACKGROUND: Leukapheresis for peripheral blood stem cell collection is increasingly being carried out in pediatric cancer patients. Aim of this study was to report experience of the Padua Apheresis Unit on a series of children weighting < 15 kg who have undergone such an apheresis procedure. METHODS: This retrospective study includes 15 pediatric patients affected with various malignancies (neuroblastoma: 7; acute myelogenous leukemia: 3; rhabdomyosarcoma: 2; PNET: 1; retinoblastoma: 1; Burkitt's lymphoma: 1) collecting peripheral blood stem cells by a Cobe Spectra blood cell separator. Main procedure parameters, including vascular access, leukapheresis duration, blood flow rate, processed blood volumes, side effects, mononuclear and CD34+ cell yields, have been registered. RESULTS: Altogether 22 sessions have been carried out, by processing a mean of 2.8 blood volumes. No leukapheresis related complications have been recorded, such as hypotension, hypocalcemia and hypothermia. Noteworthy, in 4 procedures two or more peripheral venipunctures have been performed to ensure an adequate blood flow. CONCLUSIONS: Leukapheresis for peripheral blood stem cell collection can be safely and efficaciously carried out in pediatric patients, even weighing < 15 kg, on the condition that certain aspects of apheresis practice in children (vascular access, volume shifts, anticoagulation, side effects) are carefully considered.

Quantitative multiparametric immunophenotyping in acute lymphoblastic leukemia: correlation with specific genotype. I. ETV6/AML1 ALLs identification.

The t(12;21)(p13;q22) fusion gene is the most frequent genetic lesion described in precursor B cell acute lymphoblastic leukemia (ALL) of childhood occurring in a quarter of cases. This gene rearrangement is associated with a good outcome presenting a high response rate to chemotherapy. In spite of its potential clinical relevance, the t(12;21) translocation usually goes undetected with conventional cytogenetic procedures. In the present study we utilized an objective flow cytometric approach (multiparametric quantitative analysis) for the phenotypic characterization of this type of ALL. We studied a total of 74 precursor B-ALL children, including 21 t(12;21)+ and 53 t(12;21)- cases. Our results show that the t(12;21)(p13;q22)+ ALLs display a higher intensity of CD10 (P = 0.0016) and HLADR (P = 0.005) expression together with lower levels of the CD20 (P = 0.01), CD45 (P = 0.01), CD135 (P = 0.003) and CD34 (P = 0.03) antigens as compared to the t(12;21) cases. Moreover, as regards CD34 expression, we observed a more heterogeneous antigen expression within individual patients with higher coefficients of variation (median of 202 vs 88, P = 0.0001). A multi-variate analysis disclosed that with the immunophenotypic approach used identification of t(12;21)+ cases can be achieved with a sensitivity of 86% and a specificity of 100%. We conclude that childhood precursor B-ALL carrying the t(12;21) translocation display characteristic phenotypic features which could provide a rapid, simple, sensitive and specific screening method to select for those cases that should undergo confirmatory molecular analysis.

Hematopoietic stem cell transplantation in childhood: report from the bone marrow transplantation group of the Associazione Italiana Ematologia Oncologia Pediatrica (AIEOP).

BACKGROUND AND OBJECTIVE: Transplantation of hematopoietic stem cells from different sources is being increasingly used to treat a variety of diseases in children. Transplant procedures and indications have changed considerably during recent years. Monitoring of information about these changes is useful for interpretation of nationwide collected data. DESIGN AND METHODS: Since 1985, Centers belonging to the AIEOP (Associazione Italiana Ematologia Oncologia Pediatrica), performing hematopoietic stem cell transplants (HSCT) in children, and members of the AIEOP-Bone Marrow Transplant (BMT) Group annually report data on their transplant activity to the AIEOP-BMT Registry employing specially prepared patient-oriented forms. RESULTS: From January 1985 to December 1998, a total of 2,474 bone marrow (BM), peripheral blood (PB) or umbilical cord blood (CB) transplants were reported: 1,296 (52%) were allogeneic (Allo) and 1,178 (48%) autologous (Auto) transplants. These transplants were performed in 19 Italian Centers on 2,249 patients aged less than 17 years. Among Allo-transplants, 1,198 (92%) were performed using BM progenitor cells, whereas 49 (4%) CB, 42 (3%) were PB, 4 BM plus PB, and 3 BM plus CB allografts; they were performed using HLA-identical sibling donors in 867 cases (67%) and alternative donors (i.e. partially-matched relatives or unrelated donors) in the remaining 429 (33%) cases. Allogeneic transplants were performed on 786 (67%) patients with malignancy and on 395 (33%) patients with non-malignant disorders. In the last 6 years, the number of Allo-transplants per year exceeded that of Auto-transplants. Of the Auto-transplants, 775 (66%) were performed using BM, and 403 (34%) using PB alone or combined with BM hematopoietic stem cells. Indications for Auto-BMT were myelo-lymphoproliferative disorders in 524 (49%) cases, solid tumor in 533 (50%) cases and non-malignant disease in 11 (1%) cases. In the last 5 years, the use of PB for autografts has increased from 7% to 70%. INTERPRETATION AND CONCLUSIONS: These data reflect the development and present status of HSCT in Italy and provide a basis for patient counseling and health care planning.

[Oral granisetron solution as prophylaxis for chemotherapy-induced emesis in children: double-blind study of 2 doses]. / Granisétron en solution buvable dans la prévention des vomissements chimio-induits de l'enfant: comparaison en double aveugle de deux posologies.

This multicentric double-blind, dose-ranging study was to compare efficacy and safety of two oral doses of granisetron solution in the prevention of chemotherapy-induced emesis in children with malignant diseases : 294 children, aged 1 to 16, treated with a moderately or highly emetogenic chemotherapy were randomly assigned to receive oral granisetron either 20 microg/kg (n = 143) or 40 microg/kg (n = 151) before and 6 to 12 hours after the start of chemotherapy. Fifty-one percent of patients treated with 20 microg/kg bd of oral granisetron solution achieved a complete response (no vomiting, no worse than mild nausea, no rescue therapy and no withdrawal during the specified period) and 59% achieved a major response (no more than one episode of vomiting, no worse than mild nausea, no rescue therapy and no withdrawal during the specified period). There was no difference between the two oral doses of granisetron. Treatment was rated as good or very good by investigators in 70% of cases. In conclusion, oral granisetron suspension either at 20 microg/kg bd or at 40 microg/kg bd showed good efficacy and safety in the prevention of chemotherapy-induced emesis in children with malignant diseases. Oral granisetron solution can be used as prophylaxis of emesis in children receiving moderately or highly emetogenic chemotherapy.

Outcome of 69 allogeneic stem cell transplantations for Fanconi anemia using HLA-matched unrelated donors: a study on behalf of the European Group for Blood and Marrow Transplantation.

Allogeneic stem cell transplantation is the only treatment that can restore a normal hematopoiesis in Fanconi anemia (FA). In this retrospective multicenter study, we analyzed the results of this approach using HLA-matched unrelated bone marrow donors, and tried to identify covariates predicting the outcome of the transplant. From January 1985 to June 1998, 69 FA patients were transplanted with unrelated HLA-matched donors. Patients' characteristics before and after transplant were provided by the European group blood and marrow transplant registry and were analyzed in collaboration with the European Fanconi Anemia Registry. The 3-year probability of survival was 33%. Extensive malformations, a positive recipient cytomegalovirus serology, the use of androgens before transplant, and female donors were associated with a worse outcome. Primary graft failures were observed more frequently when female donors were used, mainly because the grafts contained lower nucleated cell doses per kilogram of recipient body weight compared with grafts coming from male donors. The probability of grade III-IV acute graft-versus-host disease (GVHD) was 34%. Elevated serum alanine/aspartate transaminases before transplantation; limb, urogenital tract, or nephrologic malformations; and non-T-cell-depleted grafts were predictors of severe acute GVHD. This study shows the dramatic impact of preexisting congenital malformations on the outcome of FA patients transplanted with HLA-matched unrelated donors. If the use of T-cell depletion has led to a dramatic reduction of acute GVHD incidence, no significant outcome improvement was observed with this approach, mainly because of an increased risk of graft failure. (Blood. 2000;95:422-429)

Interferon treatment of chronic hepatitis C in patients cured of pediatric malignancies.

BACKGROUND AND OBJECTIVE: Chronic hepatitis C was a frequent complication in patients treated for malignancy until the introduction of anti-HCV screening tests for blood donors. The association between chronic hepatitis C and progression to cirrhosis and hepatocellular carcinoma has been reported in about 20% and 5% of patients, respectively, within 20-30 years of infection. In adult patients, interferon has proved to be effective in decreasing the abnormal values of transaminases and the level of HCV viremia. Our purpose was to assess efficacy of and tolerance to interferon in a group of young patients who had acquired HCV infection during a period of chemotherapy. DESIGN AND METHODS: Interferon-a (IFN) was administered to 26 adolescents and young adults (13 males, age range 17-36 years; median age 24) with chronic hepatitis C, including 4 with hepatitis B virus co-infection, who had been treated for leukemia or solid tumor 5 to 19 years before joining this trial. Patients were treated with natural IFN alpha at a dose of 4 MU/m(2) thrice weekly for 12 months and followed up for another 6 months thereafter. RESULTS: Nine patients stopped treatment during the first 6 months because of side effects (2 cases) or lack of response. At the end of the trial, 8 (31%) cases had responded, with alanine amino-transferase normalization and clearance of hepatitis C virus (HCV) RNA. A sustained response was only documented in 15% of cases, however, irrespective of any hepatitis B virus co-infection. The 2 patients with HCV genotype 2 were both responders, whereas only 8% of those with genotype 1 responded. INTERPRETATION AND CONCLUSIONS: These data show that the efficacy of IFN in this series of young patients is similar to that reported for otherwise healthy adults with hepatitis C. Patients with genotype 2 are strong candidates for IFN treatment while other therapeutic strategies should be designed for patients with HCV genotype 1.

Features of essential thrombocythaemia in childhood: a study of five children.

Essential thrombocythaemia (ET) is usually considered a disease of the middle-aged but, with the advent of automated platelet counting, ET is diagnosed with increasing frequency in young adults and, even more rarely, in children. We report five paediatric patients (four girls and one boy, mean age 89 months) diagnosed with ET in agreement with Polycythaemia Vera Study Group criteria. The patients had a persistent thrombocytosis over 900 x 10(9)/l and, at the time of diagnosis, their platelet count ranged between 1,112 and 3,178 x 10(9)/l. A 9-month-old girl had thrombosis of the inferior cava vein, two children had headaches and two others remained asymptomatic throughout the follow-up period. Megakaryocytes in the bone marrow were increased in number. The chromosomal analysis was normal, and bcr rearrangement was always negative. None of the patients had spontaneous BFU-E or altered levels of serum erythropoietin and thrombopoietin. Two patients showed alteration of platelet aggregation, and all had decreased levels of intraplatelet serotonin. In spite of the diagnosis of ET in our patients, we are not sure that the cases reported here are really myeloproliferative disorders. The features could suggest that the cases observed may be affected by an 'idiopathic thrombocytosis' without myeloproliferation. Possible variants of ET are described in young adults, and the heterogeneous nature of ET is also suggested by our paediatric patients. Only careful long-term follow-up of patients such as these will clarify the natural history of these disorders and suggest therapeutic management.

Long-term results of the Italian Association of Pediatric Hematology and Oncology (AIEOP) acute lymphoblastic leukemia studies, 1982-1995.

The first multicentric approach to childhood acute lymphoblastic leukemia (ALL) treatment in Italy started in the early 1970s when the Associazione Italiana di Ematologia ed Oncologia Pediatrica (AIEOP) was founded. Since then the AIEOP has conducted nationwide chemotherapy protocols. Results obtained in three different periods (1982-1986, 1987-1990, 1991-1995) are reported here. Treatment schedules have been characterized by a progressive intensification of systemic therapy and by a progressive substitution of protracted intrathecal therapy for cranial irradiation as central nervous system (CNS) preventive therapy. In the third period cranial radiotherapy (CRT) has been administered only to patients at high risk of relapse or with CNS involvement at diagnosis (about 15% of the overall population). A progressive improvement of therapeutic results, with a steady reduction of isolated CNS relapse rates have been obtained in the three periods considered here. The AIEOP experience shows that CRT can be safely omitted in non-high risk patients, unless they are T-ALL patients with WBC count at the diagnosis > or =100,000/mm3, and that intensification of treatment allows the improvement of overall results with a reduction of the impact of NCI prognostic criteria. Over the years, AIEOP has also continued to foster active cooperation at an international level. In the ongoing AIEOP ALL 2000 study, conducted in cooperation with the BFM group, patients are stratified according to the presence of translocations t(9;22) and t(4;11) and to treatment response (either initial steroid therapy or induction) or minimal residual disease). This cooperation will allow an adequate recruitment of patients to answer relevant randomized questions in the context of a study in which patients are stratified according to minimal residual disease findings.

Improved long-distance polymerase chain reaction for the detection of t(8;14)(q24;q32) in Burkitt's lymphomas.

The t(8;14)(q24;q32), involving MYC gene (8q24) and the immunoglobulin heavy chain (IgH) locus (14q32), represents about 75% of all translocations in Burkitt's lymphoma (BL). Due to the great variability of the breakpoint region, a standard polymerase chain reaction assay is not sufficient for the detection of this chromosomal translocation. The availability of new and more efficient DNA polymerases that allow the amplification of genomic fragments many kilobase-pairs long, makes it possible to identify the t(8;14) in BL cells by long-distance polymerase chain reaction (LD-PCR). We have established a simplified and efficient LD-PCR for the detection of t(8;14)(q24;q32) that relies on the use of one primer specific for MYC exon II combined, in different reactions, with four primers for the IgH locus: three for the constant regions Cmu, Cgamma, and Calpha, and one for the joining region (JH). We first studied seven BL cell lines and optimized LD-PCR reaction for analysis of tumor specimens. Five of seven cell lines were positive for the t(8;14), whereas two lines derived from endemic BL were negative, as expected. Of 15 biopsies obtained from pediatric BL and subsequently analyzed, 13 (87%) were positive for the translocation detected by LD-PCR and showed a product ranging in size from 2.0 to 9.5 kb. Cmu region was involved in 6 cases, Cgamma and Calpha in 2 cases each, and JH in 3 cases. Interestingly, 2 of the tumors positive for JH showed a second, larger PCR product with the Calpha- and Cgamma-specific primer, respectively. We established that our LD-PCR method could detect 10(-3) BL cells within a population of hematopoietic cells lacking the translocation. In conclusion, our LD-PCR method represents a fast, highly sensitive, and specific tool to study sporadic BL and to detect minimal disease and residual disease in patients affected by t(8;14)-positive lymphomas.

Allergic reaction to the liposomal component of liposomal amphotericin B.

A case of severe allergic reaction arising during treatment with Ambisome and unresponsive to antihistamine and steroid medication is reported. A 2.9-year-old female child with Hurler's syndrome received an allogeneic cord blood transplant from an unrelated donor. During the aplastic phase, liposomal amphotericin B (Ambisome) was administered as part of an empirical treatment for persistent fever. The patient developed an extensive maculopapular rash and severe itching that resolved only on discontinuation of the drug. The patient subsequently had interstitial pneumonia with ingravescent respiratory failure in spite of adequate antibiotic and antiviral treatment. Treatment with conventional amphotericin B was considered essential in this critically ill patient, and the conventional formulation was administered for 20 days without causing any reaction. Severe allergic reaction to Ambisome is a rare event but, taking into account that premedication or dose testing is not recommended for this formulation, careful monitoring of the patient being treated for the first time is warranted.