Clinical, functional and genetic characterization of 16 patients suffering from chronic granulomatous disease variants - identification of 11 novel mutations in CYBB.

Chronic granulomatous disease (CGD) is a rare inherited disorder in which phagocytes lack nicotinamide adenine dinucleotide phosphate (NADPH) oxidase activity. The most common form is the X-linked CGD (X91-CGD), caused by mutations in the CYBB gene. Clinical, functional and genetic characterizations of 16 CGD cases of male patients and their relatives were performed. We classified them as suffering from different variants of CGD (X910 , X91- or X91+ ), according to NADPH oxidase 2 (NOX2) expression and NADPH oxidase activity in neutrophils. Eleven mutations were novel (nine X910 -CGD and two X91- -CGD). One X910 -CGD was due to a new and extremely rare double missense mutation Thr208Arg-Thr503Ile. We investigated the pathological impact of each single mutation using stable transfection of each mutated cDNA in the NOX2 knock-out PLB-985 cell line. Both mutations leading to X91- -CGD were also novel; one deletion, c.-67delT, was localized in the promoter region of CYBB; the second c.253-1879A>G mutation activates a splicing donor site, which unveils a cryptic acceptor site leading to the inclusion of a 124-nucleotide pseudo-exon between exons 3 and 4 and responsible for the partial loss of NOX2 expression. Both X91- -CGD mutations were characterized by a low cytochrome b558 expression and a faint NADPH oxidase activity. The functional impact of new missense mutations is discussed in the context of a new three-dimensional model of the dehydrogenase domain of NOX2. Our study demonstrates that low NADPH oxidase activity found in both X91- -CGD patients correlates with mild clinical forms of CGD, whereas X910 -CGD and X91+ -CGD cases remain the most clinically severe forms.

Impact of a Bayesian Individualization of Cyclosporine Dosage Regimen for Children Undergoing Allogeneic Hematopoietic Cell Transplantation: A Cost-Effectiveness Analysis.

BACKGROUND: Cyclosporine A (CsA) is the main drug used to prevent graft-versus-host disease in patients undergoing allogeneic hematopoietic stem cell transplantation (HSCT). CsA therapeutic drug monitoring (TDM) has been performed for ages, with studies revealing clinical benefits, but failing to examine its economic impact. In this article, the main objective was to evaluate the economic impact of the CsA TDM strategy, based on a Bayesian approach, by assessing costs related to its clinical impact. Furthermore, TDM effectiveness was analyzed for pharmacokinetics and clinical outcomes. METHODS: A cost-effective, nonrandomized, retrospective, single-center study compared 2 CsA monitoring and dose adaptation strategies in pediatric patients undergoing HSCT. From 2014 to 2016, CsA TDM was performed using a population pharmacokinetics model-coupled Bayesian approach by a pharmacist ["pharmacist-assisted individualization" (PAI)]. From 2017 to 2018, CsA TDM was performed by the clinician without a Bayesian approach (non-PAI group). HSCT costs were evaluated from the French National Insurance perspective. Economic and clinical outcomes were assessed by measuring incremental cost-effectiveness ratios. RESULTS: The study included 144 patients: 90 and 54 patients in PAI and non-PAI groups, respectively. Both groups were comparable for sociodemographic and clinical characteristics. The mean total cost per patient was significantly lower (P < 0.01) in the PAI group (€85,947) than in the non-PAI group (€100,435). Multivariate analysis revealed that TDM based on the Bayesian approach was a protective factor (odds ratio = 0.86) for severe acute graft-versus-host disease. We noted that pharmacist-based TDM was the dominant strategy. Bayesian method-based TDM allowed an increase in the percentage of target attainment at any period post-HSCT. CONCLUSIONS: CsA TDM with a Bayesian approach is a cost-effective procedure, and highlighted clinical benefits encourage the development of new TDM strategies for HSCT.

Automatic depletion with Spectra Optia allows a safe 16% reduction of red blood cell pack consumption in exchanged sickle cell anemia patients.

BACKGROUND: Chronic red blood cell exchanges (RBCXs) are frequently used to prevent complications in patients with sickle cell anemia, but the scarcity of matched red blood cell packs (RBCPs) is a serious concern. The main goal of this study was to compare the number of RBCPs used during RBCXs between the Spectra Optia (SO) device (with the automatic depletion step) and the former Cobe Spectra (CSP) device. STUDY DESIGN AND METHODS: The performances and safety of 300 SO sessions using the automatic depletion step (SO/DE) in 50 patients with sickle cell anemia under a chronic transfusion program over a 1-year period were prospectively analyzed. The numbers of RBCPs saved using this protocol compared to the SO device without depletion and to the CSP device were determined. RESULTS: The SO/DE protocol appeared to be safe, as only 5% and 17% of the sessions were characterized by a significant decrease in blood pressure and increase in heart rate (grade 2 adverse events), respectively. Postapheresis hematocrit and fraction of cells remaining reached expected values. The SO/DE protocol required 16% fewer RBCPs compared to SO without depletion, allowing a mean saving of 12 RBCPs per patient and per year and 13% fewer compared to CSP device. Interestingly, the saving was more important for patients with high total blood volume and/or high preapheresis hematocrit. CONCLUSION: The SO/DE protocol is an efficient, safe and cost-effective procedure for patients with sickle cell anemia under a chronic transfusion program.

Using Genomic Location and Coalescent Simulation to Investigate Gene Tree Discordance in Medicago L.

Several well-documented evolutionary processes are known to cause conflict between species-level phylogenies and gene-level phylogenies. Three of the most challenging processes for species tree inference are incomplete lineage sorting, hybridization and gene duplication, which may result in unwarranted comparisons of paralogous genes. Several existing methods have dealt with these processes but none has yet been able to untangle all three at once. Here, we propose a stepwise method by which these processes can be discerned using information on genomic location coupled with coalescent simulations. In the first step, highly discordant genes within genomic blocks (putative paralogs) are identified and excluded from the data set and, in the second step, blocks of linked genes are grouped according to their hybrid history. Existing multispecies coalescent software can then be applied to recover the principal tree(s) that make up the species tree/network without violating the underlying model. The potential of the approach is evaluated on simulated data derived from a species network composed of nine species, of which one is of hybrid origin, and displaying a single-gene duplication that leads to paralogous comparisons. We apply our method to an empirical set of 12 genes from 7 species sampled in the plant genus Medicago that display phylogenetic discordance. We identify the causes of the discordance and demonstrate that the Medicago orbicularis lineage experienced an episode of ancient hybridization. Our results show promise as a new way to explore phylogenetic sequence data that can significantly improve species tree inference in presence of hybridization and undetected paralogy or other causes leading to extremely discordant gene trees. [Coalescent simulation; gene tree; genomic location; hybridization; incomplete lineage sorting; paralogy; phylogenetic incongruence; principal tree; species tree.].

A cryptic species produced by autopolyploidy and subsequent introgression involving Medicago prostrata (Fabaceae).

Although hybridisation through genome duplication is well known, hybridisation without genome duplication (homoploid hybrid speciation, HHS) is not. Few well-documented cases have been reported. A possible instance of HHS in Medicago prostrata Jacq. was suggested previously, based on only two genes and one individual. We tested whether this species was formed through HHS by sampling eight nuclear loci and 22 individuals, with additional individuals from related species, using gene capture and Illumina sequencing. Phylogenetic inference and coalescent simulations were performed to infer the causes of gene tree incongruence. We found no evidence that phylogenetic differences among M. prostrata individuals were the result of HHS. Instead, an autopolyploid origin of tetraploids with introgression from tetraploids of the M. sativa complex is likely. We argue that tetraploid M. prostrata individuals constitute a new species, characterised by a partially non-overlapping distribution and distinctive alleles (from the M. sativa complex). No gene flow from tetraploid to diploid M. prostrata is apparent, suggesting partial reproductive isolation. Thus, speciation via autopolyploidy appears to have been reinforced by introgression. This raises the intriguing possibility that introgressed alleles may be responsible for the increased range exploited by tetraploid M. prostrata with respect to that of the diploids.

Second malignant neoplasm following childhood cancer: A nested case-control study of a recent cohort (1987-2004) from the Childhood Cancer Registry of the Rhône-Alpes region in France.

From a population-based cohort of cases of first cancers diagnosed between 1987 and 2004, before the patient's age of 15 years, the authors conducted a nested case-control study, matching 64 patients who experienced a second malignant neoplasm (SMN) with 190 controls. SMNs comprised 10 leukemia or myelodysplastic syndromes, 5 lymphomas induced by Epstein-Barr virus after allograft, and 49 solid tumors, including mainly 25 carcinomas (17 of the thyroid), 9 bone sarcomas, and 7 central nervous system (CNS) tumors. The median latency occurrence was 6.5 years, and that of thyroid carcinomas induced by 12 Gy fractioned total body irradiation (TBI) was 7.6 years. The relative risk (RR) of an SMN was increased by genetic and family factors and increased 17 to 69 times according to the dose of radiotherapy administered in the region for the first cancer. Age younger than 4 years at the time of radiotherapy increased the risk of SMN. Chemotherapy adjusted according to the dose of radiotherapy administered in the field yielded a greater RR of an SMN only for cumulative doses exceeding 2 g/m2 of epipodophyllotoxin but not for alkylating agents or platinum compounds. The RR of secondary leukemia increased 10-fold following high doses of epipodophyllotoxin >2 g/m2 but was not affected by alkylating agents or anthracyclines. The crude RR of a solid SMN developing after radiotherapy was very high at 18 and reached 90.7 for thyroid carcinoma after TBI, whereas the authors observed no increased risk associated with chemotherapy. These results confirm the risk of secondary leukemia after epipodophyllotoxin and of solid tumor after radiotherapy.

Childhood acute lymphoblastic leukaemia and indicators of early immune stimulation: the Estelle study (SFCE).

BACKGROUND: Factors related to early stimulation of the immune system (breastfeeding, proxies for exposure to infectious agents, normal delivery, and exposure to animals in early life) have been suggested to decrease the risk of childhood acute lymphoblastic leukaemia (ALL). METHODS: The national registry-based case-control study, ESTELLE, was carried out in France in 2010-2011. Population controls were frequency matched with cases on age and gender. The participation rates were 93% for cases and 86% for controls. Data were obtained from structured telephone questionnaires administered to mothers. Odds ratios (OR) were estimated using unconditional regression models adjusted for age, gender, and potential confounders. RESULTS: In all, 617 ALL and 1225 controls aged ⩾1 year were included. Inverse associations between ALL and early common infections (OR=0.8, 95% confidence interval (CI): 0.6, 1.0), non-first born (⩾3 vs 1; OR=0.7, 95% CI: 0.5, 1.0), attendance of a day-care centre before age 1 year (OR=0.7, 95% CI: 0.5, 1.0), breastfeeding (OR=0.8, 95% CI: 0.7, 1.0), and regular contact with pets (OR=0.8, 95% CI: 0.7, 1.0) in infancy were observed. CONCLUSIONS: The results support the hypothesis that conditions promoting the maturation of the immune system in infancy have a protective role with respect to ALL.

Parental smoking, maternal alcohol, coffee and tea consumption during pregnancy, and childhood acute leukemia: the ESTELLE study.

PURPOSE: To investigate the role of parental smoking during pre-conception and pregnancy, maternal beverage consumption (alcohol, coffee and tea) during pregnancy and their possible interactions, in the etiology of childhood acute leukemia (CL). METHODS: The ESTELLE study included 747 cases of CL [636 cases of acute lymphoblastic leukemia (ALL) and 100 cases of acute myeloblastic leukemia (AML)] diagnosed in France in 2010-2011 and 1,421 population controls frequency-matched with the cases on age and gender. Data were obtained from structured telephone questionnaires administered to the mothers. The odds ratios (OR) and their 95 % confidence intervals were estimated using unconditional logistic regression models adjusted for potential confounders. RESULTS: AML, but not ALL, was non-significantly associated with alcohol drinking during pregnancy [OR = 1.3 (0.8-2.0)] with a significant positive dose-response trend (p-trend = 0.02). Pre-conception paternal smoking was significantly associated with ALL [OR = 1.2 (1.1-1.5)] and AML [OR = 1.5 (1.0-2.3)]. CL was not associated with maternal smoking [OR = 1.0 (0.8-1.2)], or maternal coffee [OR = 0.9 (0.8-1.1)] or tea drinking [OR = 0.9 (0.8-1.1)] during pregnancy. However, a high consumption of coffee (>2 cups/day) was significantly associated with ALL [OR = 1.3 (1.0-1.8)]. CONCLUSIONS: The findings constitute additional evidence that maternal alcohol drinking during pregnancy may be involved in AML, and that paternal smoking before pregnancy may be a risk factor for CL. The role of maternal coffee drinking in CL remains unclear and should be investigated further in consortium analyses and in large birth cohort studies with exposure assessment more contemporaneous with the exposure, before the occurrence of the disease.

High methotrexate exposure and toxicity in children with t(9;22) positive acute lymphoblastic leukaemia treated with imatinib.

WHAT IS KNOWN AND OBJECTIVE: Although there is one report on the possible reduced clearance of methotrexate in an adult patient when given concomitantly with imatinib, there is little information on the possible pharmacokinetic interaction. We report on three cases of delayed elimination of methotrexate in children with chromosome Philadelphia-positive acute lymphoblastic leukaemia treated concomitantly with imatinib. CASE SUMMARY: Three patients, aged 9-17 years, presented with high methotrexate blood levels following co-administration of imatinib and high-dose methotrexate. Two patients presented with clinical symptoms (nausea, epigastric pain and mucositis, acute renal failure, liver cytolysis). One patient required extra supplementary folinic acid doses than used in the standard protocol and one child required the use of carboxypeptidase-G2. WHAT IS NEW AND CONCLUSION: There is an apparent pharmacokinetic interaction between imatinib and methotrexate in children. Several mechanisms could explain this interaction, including competition for BCRP or ABCB transporters. Temporary withdrawal of imatinib may be necessary for preventing severe methotrexate-related adverse events.

Cytomegalovirus infection in pediatric allogenic hematopoietic stem cell transplantation. A single center experience.

We report a retrospective analysis of Cytomegalovirus (CMV) infection: incidence, recurrence, resistance, and subsequent disease of 81 children who underwent allogenic hematopoietic stem cell transplantation (HSCT). The recipient and/or donor's CMV serology was positive prior to transplant [recipient (R+) and/or donor (D+)]. CMV was monitored by RT-PCR starting from the first week post transplant. Forty patients showed CMV infection (49, 5%). Of them 10 manifested CMV disease leading to four deaths. In univariate analysis, factors associated with CMV infection were CMV R+ P < .01, CMV R+/D+ pair P < .01, nonbone marrow (BM) stem cell source P < .05, nonirradiation conditioning regimen P < .05, Antithymocyte globulin (ATG) P < .01. Factors associated with CMV resistance were: >1 HLA allele mismatch P < .05, CMV R +/D-pair P < .01, CMV D-P < .01, non-BM P < .05, nongenoidentical transplant P < .01. CMV disease was influenced by >1 HLA allele mismatch (P < .001), non-BM (P < .01). On multivariate analysis, CMV R+/D- (P < .05), corticosteroids ≥2 mg/kg P < .01, ATG P < .01 and non-BM (P < .05) were independent factors for CMV infection. CMV R+ transplant is associated with more CMV infection and resistance to preemptive treatment. Prolonged immune suppression (IS) worsens outcome of CMV infection and should be shortened whenever possible.

[Potential implication of the IgA-pIgR system in idiopathic pulmonary fibrosis]. / Implications potentielles du système IgA-pIgR dans la fibrose pulmonaire idiopathique.

Idiopathic pulmonary fibrosis (IPF) is a lethal respiratory disease characterized by the excessive deposition of extracellular matrix in the alveolar zones. The bronchiolar epithelium has been implicated in the development of this disease and is capable of secreting IgA into the airway lumen thanks to its expression of the polymeric immunoglobulin receptor. Several elements indicate a dysregulation of this system, such as raised serum IgA levels in IPF patients and the pro-fibrotic effect of IgA on several key cell types. Our work aims at studying the underlying mechanisms so as to better understand the role of IgA mucosal immunity in this disease.

Influence of glioma tumour microenvironment on the transport of ANG1005 via low-density lipoprotein receptor-related protein 1.

BACKGROUND: ANG1005 consists of three molecules of paclitaxel conjugated via ester bonds to the 19-amino-acid peptide Angiopep-2. The new chemical agent has been shown to cross the blood-brain barrier (BBB) by receptor-mediated transcytosis via low-density lipoprotein receptor-related protein 1 (LRP1). The experiments here examined the role of LRP1 in the subsequent endocytosis of drug into cancer cells. METHODS: Localisation of ANG1005 and Angiopep-2 was examined by immunohistochemistry and in-vivo near-infrared fluorescence imaging in mice carrying orthotopic glioma tumours. Transport of ANG1005 and Angiopep-2 was examined in U87 glioblastoma cell lines. RESULTS: Systemically administered ANG1005 and Cy5.5Angiopep-2 localised to orthotopic glioma tumours in mice. The glioma transplants correlated with high expression levels of LRP1. Decreasing LRP1 activity, by RNA silencing or LRP1 competitors, decreased uptake of ANG1005 and Angiopep-2 into U87 glioblastoma cells. Conversely, LRP1 expression and endocytosis rates for ANG1005 and Angiopep-2 increased in U87 cells under conditions that mimicked the microenvironment near aggressive tumours, that is, hypoxic and acidic conditions. CONCLUSION: ANG1005 might be a particularly effective chemotherapeutic agent for the wide array of known LRP1-expressing brain and non-brain cancers, in particular those with an aggressive phenotype.

CNS-3 status remains an independent adverse prognosis factor in children with acute lymphoblastic leukemia (ALL) treated without cranial irradiation: Results of EORTC Children Leukemia Group study 58951.

AIM: To evaluate the prognostic significance of initial central nervous system (CNS) involvement of children with acute lymphoblastic leukemia (ALL) enrolled in the EORTC 58951 trial. PATIENTS AND METHODS: From 1998 to 2008, 1930 ALL patients were included in the randomized EORTC 58951 trial. Overall treatment intensity was adjusted according to known prognostic factors including the level of minimal residual disease after induction treatment. CNS-directed therapy comprised four to 11 courses of i.v. methotrexate (5g/m2), and 10 to 19 intrathecal chemotherapy injections, depending on risk group and CNS status. Cranial irradiation was omitted for all patients. RESULTS: The overall 8-year event-free survival (EFS) and overall survival (OS) rates were 81.3% and 88.1%, respectively. In the CNS-1, TPL+, CNS-2, and CNS-3 groups, the 8-year EFS rates were 82.1%, 77.1%, 78.3%, and 57.4%, respectively. Multivariable analysis indicated that initial CNS-3 status, but not CNS-2 or TLP+, was an independent adverse predictor of outcome. The 8-year incidence of isolated CNS relapse was 1.7% and of isolated or combined CNS relapse it was 3.7%. NCI high-risk group, male sex, CNS-2 and CNS-3 status were independent predictors for a higher incidence of any CNS relapse. CONCLUSIONS: CNS-3 status remains associated with poor prognosis and requires intensification of both systemic and CNS-directed therapy. This trial was registered at https://clinicaltrials.gov/under/NCT00003728.

Acute childhood leukaemia and residence next to petrol stations and automotive repair garages: the ESCALE study (SFCE).

BACKGROUND: The association between acute childhood leukaemia and residing next to petrol stations and automotive repair garages was analysed in a national registry-based case-control study carried out in France in 2003-2004. METHODS: Population controls were frequency matched with cases on age and gender. Data were collected by standardised telephone interview with the mothers. The latter were asked to report the proximity of their homes to petrol stations, automotive repair garages and other businesses from the conception of the index child to the diagnosis (for cases) or interview (for controls). Odds ratios were estimated using unconditional regression models adjusted for age, gender, number of children under 15 years of age in the household, degree of urbanisation and type of housing. RESULTS: 765 cases of acute leukaemia and 1681 controls were included. Acute leukaemia was significantly associated with residence next to petrol stations or automotive repair garages (OR 1.6, 95% CI 1.2 to 2.2) and next to a petrol station (OR 1.9, 95% CI 1.2 to 3.0). The OR showed no tendency to increase with duration of exposure. The results were not modified by adjustment for potential confounding factors including urban/rural status and type of housing. CONCLUSIONS: The results support the findings of our previous study and suggest that living next to a petrol station may be associated with acute childhood leukaemia. The results also suggest that the role of low-level exposure to benzene in acute childhood leukaemia deserves further evaluation.

Is Acute Myeloblastic Leukemia in Children Under 2 Years of Age a Specific Entity? A Report from the FRENCH ELAM02 Study Group.

The clinical and biological characteristics of children under 2 years (infants) with acute myeloid leukemia (AML) are different from those of older children. We aimed to describe the specific characteristics of this population and the potential factors that influence the prognosis. We analyzed data concerning 438 children with newly-diagnosed AML treated in the ELAM02 protocol between March 2005 and December 2011, of which 103 were under 2 years old at diagnosis. The evaluation criteria were overall survival (OS) and event-free survival (EFS) of infants vs older children. The clinical and biological features were secondary criteria. Infants presented more frequent extra-medullary presentation than older children. They had a significantly higher proportion of skin lesions and central nervous system involvement (15% vs 3%, p < 0.0001 and 26% vs 12%, p = 0.0005, respectively). The global incidence of KMT2A rearrangements was nearly 55% for infants vs 11% for older children (p < 0.0001). Median 5-year OS was 70.4% for infants vs 71.4% for older children (p = 0.83). Five-year EFS was 67% for infants vs 58% for older children (p = 0.27). Infants with AML represent a cohort of patients with specific clinical and biological features. These remarkable differences had no significant impact on their outcome in the ELAM02 protocol.

Invasive aspergillosis and allogeneic hematopoietic stem cell transplantation in children: a 15-year experience.

Despite progress in diagnosis and treatment, invasive aspergillosis (IA) remains a principal cause of mortality due to infection after allogeneic hematopoietic stem cell transplantation (AHSCT). In order to clarify the course of IA among children receiving an AHSCT before the advent of new drugs such as voriconazole or caspofungin, we retrospectively reviewed the medical records of all proven and probable IA between January 1986 and December 2000. 1) Ten children developed IA after AHSCT, mostly long after transplantation. Overall incidence was 2.7%. Seven of those children experienced 1 or more complications after AHSCT and before IA. Mortality was 90% with a median survival of 23 days (2-90). 2) Five children underwent AHSCT after a previous episode of IA. All patients were treated with systemic antifungal therapy combined with surgery. Median time between IA and AHSCT was 110 days (73-370). Two children were diagnosed with IA relapse after transplantation. One child was cured while the other died of IA and AHSCT complications. AHSCT could be considered even in the setting of previous IA, but established strategies implementing newer less toxic antifungal agents as treatment or prophylaxis in high-risk patients are needed.

[Long term mortality of five-year survivors of childhood cancer in Rhône-Alpes region]. / Mortalité tardive après cancer des enfants survivants à cinq ans dans la région Rhône-Alpes.

BACKGROUND: The population of survivors of childhood cancer is currently growing. Studies from other countries have shown an increased risk of late mortality. In order to measure this risk within a French cohort, the mortality of children who had survived five years from a cancer diagnosis were compared to the mortality of the general population, according to follow-up interval and cancer and treatment characteristics. METHODS: The study population consisted of 635 children diagnosed with cancer before the age of 15 who had survived at least five years, and were registered in the Rhone-Alpes region cancer registry from 1987 to 1992. Mortality was compared with general population rates of the Rhone-Alpes region to assess age and sex standardized mortality ratio (SMR) and absolute excess risk of death. RESULTS: The median follow-up of children was 14.0 years. Among the 42 observed deaths, 71.4% were attributed to a recurrence of the original cancer, 9.5% to a second cancer. The 15-year cumulative risk of death, all causes, was 7.1%. The overall mortality of the cohort was 20.7 fold greater than the general population (95% CI: 14.9-27.9), and the absolute excess risk of 6.9 per 1000 persons-years. The long term excess-mortality was higher in case of recurrence of original cancer (SMR=99.9, 95% CI: 67.9-141.9, absolute excess risk 35.4 per 1000 persons-years); it was raised during the five to nine years follow-up interval after diagnosis (SMR=33.8, 95% CI: 23.2-47.3) mainly due to the primary malignancy, and decreased after (10-14 years follow-up interval SMR=6.5, 95% IC 2.4-14.2). CONCLUSION: The late mortality of childhood cancer is significantly increased during the five to nine years following diagnosis and decreases after, but the cohort follow-up has to be extended in order to assess outcome beyond 15 years after diagnosis.

[Disseminated nocardiosis in a child with acute lymphoblastic leukemia]. / Nocardiose viscérale disséminée chez un enfant atteint de leucémie aiguë lymphoblastique.

Nocardiosis is a rare infectious disease in children. We report here a disseminated nocardiosis in a child with acute lymphoblastic leukemia. The patient presented prolonged febrile neutropenia and nodular pneumopathy. Based on the amplification of a 16S rDNA, a PCR assay detected Nocardia sp. in the patient's bronchoalveolar lavage (BAL) fluid. Culture of BAL samples yielded Nocardia nova colonies after 2 weeks of incubation. Hepatic, splenic, renal and cerebral localisations were detected on extension checkup. trimethoprime-sulfamethoxazole and amikacine were started given the results of PCR assay, with a good response. Improvement of the patient's general condition led to complete chemotherapy under ciprofloxacine and ceftriaxone treatment, without nocardiosis reactivation. Nocardiosis is a rare complication in children with acute lymphoblastic leukemia. trimethoprime-sulfamethoxazole prophylaxis is widely used to prevent Pneumocystis jiroveci infection in children with haematologic malignancies. As Nocardia species are usually sensible, trimethoprime-sulfamethoxazole could play a role in Nocardia prophylaxis in such population. In our patient, compliance with trimethoprime-sulfamethoxazole had been low. Nocardia species are relatively fastidious growth bacteria and are difficult to isolate with classical bacteriological techniques. Molecular methods are now available, with a good sensitivity and fast results allowing to start an appropriate antibiotherapy before culture results, as early treatment is a major prognosis factor in nocardiosis. Nocardia infection should be suspected in case of nodular pneumopathy in immunocompromised children. An extension checkup should be performed to detect secondary localisations.

[Blueberry Muffin Baby and spontaneous remission of neonatal leukaemia]. / Leucémie aiguë néonatale et Blueberry Muffin syndrome: à propos d'un cas spontanément régressif.

Blueberry Muffin baby is a rare neonatal skin disorder. Many causes are known, examples are congenital infections, hemolysis and tumors. We report on a newborn presenting with Blueberry Muffin syndrome and an adrenal mass which lead to the diagnosis of neuroblastoma. Actually, it corresponded to an acute monoblastic leukaemia with an adrenal localization and a cerebrospinal fluid involvement. Leukaemia should always be considered in such patients, even in the absence of blasts on white blood cells count and bone marrow examination, as in this patient. This observation was also unusual due to spontaneous remission. The patient is in complete remission at 1 year follow-up.

Eculizumab and thrombotic microangiopathy after hematopoietic stem cell transplantation: A report on its efficacy and safety in two pediatric patients.

BACKGROUND: Thrombotic microangiopathy (TMA) is a severe complication after hematopoietic stem cell transplantation (HSCT), with the reported mortality rate in such cases usually reaching 90%. CASES: We report on two pediatric cases of patients successfully treated by eculizumab for severe HSCT-TMA, occurring in two girls (8.4 and 3.6 years). The first patient developed TMA with hematologic abnormalities and renal/pulmonary lesions after allogeneic HSCT for Philadelphia-positive acute lymphoblastic leukemia; she received eculizumab 7 months after HSCT, with a dramatic improvement of renal function. The second patient developed severe TMA (cardiac tamponade, renal failure requiring dialysis, gastritis) after autologous HSCT for metastatic neuroblastoma. She received eculizumab for 7 months, with a dramatic improvement of renal function. No side effects were observed. CONCLUSION: The use of eculizumab as first-line therapy in pediatric patients with severe HSCT-TMA with multisystemic lesions appears promising. Larger international studies are required to confirm its benefit and safety for this specific indication.