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I Thuret

Publications and source records attributed to I Thuret.

At least 19 recordsLinked to original sources
PubMed2005

[Evans' syndrome: a retrospective study from the ship (French Society of Pediatric Hematology and Immunology) (36 cases)].

UNLABELLED: Evans' Syndrome (ES) is defined as the combination of immune thrombocytopenia (ITP) and autoimmune haemolytic anemia (AIHA), in the absence of any known underlying etiology. Pathophysiology, epidemiology and outcome remain unclear. POPULATION: Thirty-six children (20 male, 16 female), who were diagnosed in the SHIP french centres (Société d'hématologie et d'immunologie pédiatrique) between 1990 and 2002 with ES, were included in this retrospective study. RESULTS: Median age at diagnosis was 4 years. In 21 children, ES occurred in the setting of consanguinity, family history of autoimmune/inflammatory disease, associated autoimmune disorder or immunoregulatory abnormalities (serum imunoglobulins, peripheral blood lymphocytes subsets, low level of the C3-C4 complement components, nuclear antibodies). Several successive treatments were used in this serie (median: 3, range: 0-10) including corticosteroid therapy (35/36), intravenous immunoglobulins (32/36), immunosuppressive agents (14/36), splenectomy (9/36) and anti CD 20 monoclonal antibodies (6/36). Patients with a low level of serum immunoglobulins were more often non-responders to corticosteroidtherapy/intravenous immunoglobulins and required more frequently further therapy (P=0.03). Three patients died (intracranial bleeding, N=2, Guillain-Barre syndrome; N=1). CONCLUSION: ES was a severe, life-threatening disease, requiring aggressive immunosuppressive therapy in as many as half the patients. Our forthcoming study aims to (i) describe homogeneously-studied and prospectively-analysed cohort of childhood ES, (ii) separate ES from specific immune deficiency (especially fas gene mutations), generalised autoimmune/inflammatory disorders and genetic diseases, (iii) identify well-defined ES subsets, (iv) establish prognostic factors and optimal treatment within these subsets.

Adolescent↗
PubMed2005

Treatment of childhood acute myeloblastic leukemia: dose intensification improves outcome and maintenance therapy is of no benefit--multicenter studies of the French LAME (Leucémie Aiguë Myéloblastique Enfant) Cooperative Group.

From 1989 to 1998, 341 children were included in the French multicentric LAME (Leucémie Aiguë Myéloblastique Enfant) trials. A total of 309 children were registered in the LAME 89/91 protocol. This intensive regimen included an induction phase (mitoxantrone plus cytarabine), two consolidation courses, one containing timed-sequential high-dose cytarabine, asparaginase and amsacrine; 276 (90%) achieved a CR. The 5-year overall survival (OS) and event-free survival (EFS) were 60+/-4 and 48+/-4%, respectively. From 1997, timed-sequencing of the LAME SP induction chemotherapy led to an unacceptable frequency of consolidation delay; future improvements are unlikely to come from further increases in intensity. The role of allogenic bone-marrow transplantation from an HLA-identical sibling in CR1 was examined. The disease-free survival (DFS) was 52+/-4% for non-allografted patients and 57+/-7% for allografted patients (P=NS); a better OS for allografted patients was shown and could be related either to allo-BMT early in CR1 or to a second allo-BMT in CR2. For the complete responders after consolidation therapy, the 5-year OS was significantly better in patients randomized for no maintenance therapy (MT-) than in patients randomized for MT (77.6+/-8 vs 59+/-8%; P=0.05), while the 5-year DFS was not significantly different. Exposure to low-dose MT might contribute to clinical drug resistance and treatment failure in relapsing patients.

Adolescent↗
PubMed2004

[When to initiate antiretroviral therapy in HIV-infected children?].

Administration of highly active antiretroviral treatment (HAART) has led in the developed world to a dramatic reduction in the incidence of HIV related pediatric mortality. HAART is now the standard-of-care therapy in infected children but the occurrence of short- and long-term drug-related toxic effects and emergence of drug-resistant viral variants temper its success. In children, both CD4 cell percent and viral load have independent predictive value for disease progression, CD4 cell being the stronger predictor of AIDS and death. Concerning children aged 12 months or oder current French recommendations for immediate therapy are based on the presence of clinical symptoms (of categories B or C) or the occurrence of a severe immunodeficiency (CD4 cell percent < 15%). In infants, risk of disease progression is higher and the viral load and CD4 percent are less reliable markers. HAART should theoretically be initiated in all infants in order to prevent HIV encephalopathy and early death. However, viral failure under HAART is often encountered in children less than 12 months because of high levels of replication as well as limited data on pharmacokinetics and drug dosing. A possible alternative approach for infants without risk factor for early progression is to defer HAART under close mentoring.

Antiretroviral Therapy, Highly Active↗
PubMed2004

[Thyroid dysfunction after haematopoietic stem cell transplantation during childhood].

UNLABELLED: To evaluate the percentage and risk factors of thyroid dysfunction in 79 children who underwent bone marrow transplantation in a single centre. PATIENTS AND METHODS: The mean age of the cohort was 6.8 and mean follow-up 5.5 years. The 79 patients were divided in two groups according to the pretransplant conditioning regimen: fractionated total body irradiation (TBI)(N=54), chemotherapy with Busulphan (N=25). Thyroid function was evaluated by thyroid-stimulating hormone (TSH) and free thyroxine (fT4) tests. Overt hypothyroidism was defined by low fT4 blood levels and TSH > 4 mU/l, and compensated hypothyroidism by normal fT4 index and TSH >4 mU/L. RESULTS: The six-year probability of hypothyroidism was 36 +/-6% for the whole group of 79 patients, 49 +/-8% after TBI and 9 +/-6% in the Busulphan group (P <0.001). Neither gender, nor primary disease, nor presence of graft versus host disease were found to be statistically significant for occurrence of hypothyroidism in the TBI group. However, a younger age seemed to influence statistically the 6-year probability of hypothyroidism in the TBI group: 59 +/-9% if age <7.7 years versus 34 +/-13% if age >7.7 years (P =0.02). CONCLUSION: A careful follow-up of thyroid function is recommended even without TBI conditioning regimen. Young age as a potential risk factor of hypothyroidism has never been described and needs to be studied in a larger cohort.

Adolescent↗
PubMed2003

Lymphocyte-predominant Hodgkin's lymphoma in children: therapeutic abstention after initial lymph node resection--a Study of the French Society of Pediatric Oncology.

PURPOSE: To clarify treatment strategy for lymphocyte-predominant Hodgkin's lymphoma (LPHL), the French Society of Pediatric Oncology initiated a prospective, nonrandomized study in 1988. Patients received either standard treatment for Hodgkin's lymphoma or were not treated beyond initial adenectomy. PATIENTS AND METHODS: From 1988 to 1998, 27 patients were available for study. Twenty-four patients were male, and median age was 10 years (range, 4 to 16 years). Twenty-two, two, and three patients had stage I, II, and III disease, respectively. Thirteen patients (stage I, n = 11; stage III, n = 2) received no further treatment after initial surgical adenectomy (SA). Fourteen patients received combined treatment (CT; n = 10), involved-field radiotherapy alone (n = 1), or chemotherapy alone (n = 3). The two groups were comparable for clinical status, treatment, and follow-up. RESULTS: Twenty-three of 27 patients achieved complete remission (CR). With a median follow-up time of 70 months (range, 32 to 214 months), overall survival to date is 100%, and overall event-free survival (EFS) is 69% +/- 10% (SA, 42% +/- 16%; CT, 90% +/- 8.6%; P <.04). If we considered only the patients in CR after initial surgery (n = 12), EFS was no longer significantly different between the two groups. Patients with residual mass after initial surgery (n = 15) had worse EFS if they did not receive complementary treatment (P <.05). CONCLUSION: Although based on a small number of patients, our study showed that (1). no further therapy is a valid therapeutic approach in LPHL patient in CR after initial lymph node resection, and (2). complementary treatment diminishes relapse frequency but has no impact on survival.

Adolescent↗
PubMed2001

[Severe upper airway obstruction in infectious mononucleosis: a life emergency].

BACKGROUND: Upper airway obstruction can represent a severe, life-threatening complication of infectious mononucleosis. We report a rare case of airway obstruction in a child with infectious mononucleosis associated with herpes virus infection, and we discuss management strategy that can be proposed in such cases. CASE REPORT: A 9-year-old girl was hospitalised in intensive care unit for obstructive dyspnea during infectious mononucleosis. Despite five days of corticosteroids and tracheal intubation, persistent pharyngo-tonsillar tumefaction led us to perform a surgical adenotonsillectomy. This latter treatment allowed immediate tracheal extubation and a rapid recovery. Histology showed a herpes virus infection associated with infectious mononucleosis. CONCLUSION: Maintaining airway opening in infectious mononucleosis needs sometimes to use instrumental interventions: nasal trumpet, endotracheal intubation, even tracheostomy. Early tonsilloadenoidectomy may relieve airway obstruction and allow a rapid recovery in the most severe cases. Airway obstruction in infectious mononucleosis may be aggravated by concomitant herpes virus infection that should be searched for in this situation, in order to adapt the treatment.

Airway Obstruction↗
PubMed2001

[Therapeuetic management of patients with thalassemia major].

In industrialised countries, the use of regular blood transfusions and of chelation therapy with Deferoxamine (DFO) has led to the transformation of thalassemia major from a fatal disease in early childhood to a chronic illness associated with prolonged survival. Transfusion regimens maintaining pretransfusion hemoglobin > 9-10 g/dl are effective in suppressing erythroid marrow expansion. Long term DFO therapy using subcutaneous infusions at least 4-6 d a week have clearly demonstrated major effects on iron overload complications. DFO treatment reduces excessive iron and prevents cardiac, hepatic and endocrine diseases. Nonetheless, compliance is difficult for many patients and the cost of DFO limits its use in developing countries. The only oral iron chelating agent that has been investigated extensively is Deferiprone (L1). In France, this oral agent can be administered in patients experiencing toxic side effects under DFO treatment. Since 1981 more than 1500 bone-marrow transplants have been performed word-wide, mostly in Italy. Allogenic BMT is currently able to cure 85% of thalassemic children with an available HLA matched sibling donor.

Blood Transfusion↗
PubMed2000

Parameters involved in the recognition of fresh human leukemic blasts by tumor-specific cytolytic T cell clones: a model study.

Although clinical experience and in vitro data provide evidence of an anti-leukemic activity of T cells, there are few examples of recognition of leukemic cells by tumor-specific T cells in vitro. Tumor antigens encoded by the MAGE genes are useful tools to study this recognition. We tested the sensitivity to recognition and lysis by anti-MAGE CTL clones of MAGE-A1 positive cell lines HL60 and K562, after transfection with an HLA-A1 construct, and of fresh leukemic blasts from 10 HLA-A2 patients, after incubation with a peptide encoded by gene MAGE-A3. The presentation of MAGE antigens by leukemic cell lines and fresh leukemic blasts induced TNF secretion and cytotoxicity by MAGE-specific CD8(+) CTL clones. The amount of peptide presented by the leukemic blasts, more than the level of expression of HLA class I, adhesion or costimulatory molecules, was the major limiting factor for recognition. These data indicate that leukemic cells may be targeted by T cells showing specificity for a leukemia antigen.

Antigens, Neoplasm↗
PubMed2000

Immune reconstitution and outcome after unrelated cord blood transplantation: a single paediatric institution experience.

We report the outcome of 12 children who underwent unrelated cord blood transplant (U-CBT) in a single institution between February 1997 and July 1998. The 1 year event-free survival was 67% (95% CI of 26%). Four children died with infectious complication as cause of death in three cases. Immune reconstitution was studied during first year post transplant by assaying total lymphocyte counts, B cells, NK cells and T cell subsets in the eight disease-free surviving patients. We observed a prompt recovery of CD19+ cell number which was greater than 500/microl at 9 months for all patients except the one with severe cGVHD. B cells constituted the predominant lymphocyte subset at 6 and 9 months post transplant with normal or elevated B cell numbers according to normal paediatric range. We noted normal serum immunoglobulin levels at 6 months post transplant for IgA and IgM and at 9 months for IgG. The CD3+ cell count and particularly the CD3+CD8+ T cell subset remained depressed until 12 months post transplant. Six months after unrelated CBT, seven out of eight patients had less than 100 CD3+CD8+ cells/microl. CD3+CD4+ cell recovery was less impaired with all children achieving an absolute count of CD3+CD4+ cells greater than 200/microl during the first year in a median of 5 months. The percentage of NK cells was elevated during the first 6 months after CBT but their absolute count remained within the normal range. Bone Marrow Transplantation (2000) 25, 53-57.

Adolescent↗
PubMed2000

Molecular basis of haemoglobinopathies and G6PD deficiency in the Comorian population.

INTRODUCTION: The Comoro archipelago is characterised by a high prevalence of red cell genetic disorders such as G6PD deficiency and haemoglobinopathies, being a region endemic for malaria. Over the last 15 years, the city of Marseilles in France has become the main destination for Comorian immigrants. This Comorian community includes patients with sickle cell disease, sickle cell/beta-thalassaemia trait, thalassaemias and G6PD deficiency. MATERIALS AND METHODS: Allele frequencies for haemoglobin S, beta-thalassaemia and G6PD deficiency were determined from neonatal and prenatal screenings of the Comorian community. Haemoglobin fractions were detected by isoelectrofocalisation, and the quantitation of HbS, HbA, HbA(2) and HbF was performed by cation exchange high performance liquid chromatography. The molecular study involved 31 alleles carrying the betaS mutation (Cd 6 [A-->T]), six beta-thalassaemic alleles and 17 G6PD-deficient alleles, selected from a group of carriers or affected subjects. RESULTS: Allele frequencies were 3% for haemoglobin S, 1% for beta-thalassaemia trait and 9.5% for G6PD deficiency. Molecular analysis had revealed that the African alleles are predominant, being present in almost all the subjects studied. Mediterranean alleles were found for all the beta-thalassaemia mutations and for three G6PD chromosomes out of 17. CONCLUSION: These data are consistent with the mixed Arab and African origin of the population of the Comoro Islands, and are of clinical interest in prenatal and newborn screening plans.

Alleles↗
PubMed2000

Relationship between efficacy, tolerance, and plasma drug concentration of ritonavir in children with advanced HIV infection.

The relationship between ritonavir plasma concentration, efficacy, and tolerance was evaluated in 31 children with advanced HIV infection who were receiving a triple therapy with ritonavir as protease inhibitor. Median CD4+ lymphocyte count and median viral load before the initiation of ritonavir-containing combination therapy were 1320 cells/mL and 5 log10 copies/mL, respectively. Ritonavir was given at a dose ranging from 300 to 450 mg/m2 twice daily. The median follow-up of triple therapy was 19 months. Response was defined as a drop of viremia of more than 1 log. Plasma drug levels were determined twice during the observation period: after at least 4 weeks and after 3 months of combined treatment. Samples were collected before (residual) and 2 hours (T2) after drug intake. Cholesterol, triglycerides, alanine transaminase, aspartate transaminase, and gamma-glutamyl transpeptidase were assessed at the same time. The median values of ritonavir residual and T2 levels were 1.64 mg/L and 5.9 mg/L at observation 1 and 3.35 mg/L and 6.29 mg/L at observation 2, respectively. According to virologic response, median residual concentrations of ritonavir were 3.17, 2.52, and 1.04 mg/L for the complete, the partial, and the no-response groups. The authors observed a wide intersubject variability of ritonavir concentrations with an increase in residual levels between the two observation periods. Residual levels were correlated with virologic response whereas there was no direct association between T2 levels and long-term response. Patients with complete or partial response displayed statistically significantly higher residual concentrations than the no-response group. No correlation could be demonstrated between elevated plasma drug concentrations and abnormal cholesterol or triglycerides values. These results emphasize the importance of a sustained high ritonavir concentration to achieve optimal treatment efficacy. Furthermore, these results prove the clinical benefit of therapeutic drug monitoring and could potentially improve patient evaluation in terms of treatment efficacy, compliance, and viral resistance.

Adolescent↗
PubMed2000

Multicenter prospective study of children with sickle cell disease: radiographic and psychometric correlation.

After obtaining familial informed consent, between January 1996 and July 1997, 173 children (5 to 15 years old) with sickle cell disease were enrolled in a prospective multicenter study using blood screening, transcranial Doppler ultrasonography (n = 143), cerebral magnetic resonance imaging (n = 144), and neuropsychologic performance evaluation (n = 156) (Wechsler Intelligence tests WISC-III, WIPPSI-R), which were also performed in 76 sibling controls (5 to 15 years old). Among the 173 patients with sickle cell disease (155 homozygous for hemoglobin SS, 8 sickle cell beta0 thalassemia, 3 sickle cell beta+ thalassemia, 7 sickle cell hemoglobin C disease SC), 12 (6.9%) had a history of overt stroke, and the incidence of abnormal transcranial Doppler ultrasonography (defined as mean middle cerebral artery velocity > 200 cm/sec or absent) was 8.4% in the overall study population and 9.6% in patients with homozygous sickle cell anemia The silent stroke rate was 15%. Significantly impaired cognitive functioning was observed in sickle cell disease patients with a history of stroke (Performance IQ and Full Scale IQ), but also in patients with silent strokes (Similarities, Vocabulary, and Verbal Comprehension). However, infarcts on magnetic resonance imaging were not the only factors of cognitive deficit: Verbal IQ, Performance IQ, and Full Scale IQ were strongly impaired in patients with severe chronic anemia (hematocrit < or = 20%) and in those with thrombocytosis (platelets > 500 x 10(9)/L). Multivariate logistic regression analysis showed that abnormal magnetic resonance imaging (odds ratio [OR] = 2.76) (P = .047), hematocrit < or =20% (OR = 5.85) (P = .005), and platelets > 500 x 10(9)/L (OR = 3.99) (P = .004) were independent factors of cognitive deficiency (Full Scale IQ < 75) in sickle cell disease patients. The unfavorable effect of low hematocrit has already been suggested, but this is the first report concerning an effect of thrombocytosis and showing that silent stroke alone is not a factor of cognitive deficit when not associated with low hematocrit or thrombocytosis. The effect of hydroxyurea, which is known to increase hematocrit and decrease platelet count, on cognitive functioning of sickle cell patients should be evaluated prospectively.

Adolescent↗
PubMed2000

Localized childhood Hodgkin's disease: response-adapted chemotherapy with etoposide, bleomycin, vinblastine, and prednisone before low-dose radiation therapy-results of the French Society of Pediatric Oncology Study MDH90.

PURPOSE: The French Society of Pediatric Oncology MDH82 study demonstrated the effectiveness of 20 Gy irradiation of involved fields after doxorubicin, bleomycin, vinblastine, and dacarbazine (ABVD) or mechlorethamine, vincristine, procarbazine, and prednisone/ABVD chemotherapy in children with localized Hodgkin's disease (HD). The response to primary chemotherapy was the only predictor of survival. To reduce long-term treatment complications without compromising efficacy, the MDH90 study was based on a new chemotherapy regimen devoid of both alkylating agents and anthracycline, followed by 20 Gy of radiotherapy (RT) for good responders. PATIENTS AND METHODS: From January 1990 to July 1996, 202 children were enrolled from 30 institutions. Good responders to four cycles of vinblastine, bleomycin, etoposide (VP16), and prednisone (VBVP) were given 20 Gy of RT and no further therapy. Poor responders were given vincristine, procarbazine, prednisone, and doxorubicin. After a second evaluation, good responders were given 20 Gy of RT, and poor responders were given 40 Gy of RT. RESULTS: One hundred seventy-one patients (85%) were good responders to VBVP, 27 (15%) were poor responders, and four did not respond. With a median follow-up of 74 months (range, 25 to 117 months), the 5-year overall survival rate (mean +/- SD) is 97.5% +/- 2.1%, and the event-free survival rate (mean +/- SD) is 91.1% +/- 1.8%. Significant predictors of worse event-free survival in multivariate analysis were hemoglobin < 10.5 g/L, "b" biologic class, and nodular sclerosis. CONCLUSION: These results suggest that most children with clinical stage I and II HD can be treated with chemotherapy devoid of alkylating agents and anthracycline, followed by low-dose RT.

Adolescent↗
PubMed2000

[Legionella pneumophila: unusual lung and hepatic manifestations].

We report an uncommon presentation of Legionella pneumophila infection following a placentalblood transplantation in an immunodeficient child. The patient presented with lung nodules and liver abscesses. We discuss how a digestive contamination can be suspected.

Autopsy↗
PubMed1999

Combination antiretroviral therapy including ritonavir in children infected with human immunodeficiency.

OBJECTIVE: To assess the efficacy of combination therapy that includes ritonavir in HIV-1 infected children. DESIGN: A monocentric retrospective study. PATIENTS AND METHODS: Twenty-two children with a minimum follow-up of 6 months under triple therapy including ritonavir were analysed for treatment efficacy. At entry, all the patients were protease inhibitor naive and all but two had received previous antiretroviral therapy during a median period of 5 years. Their initial median CD4+ lymphocyte count and viral load were 121 x 10(6)/l and 5.08 log10 copies/ml, respectively. Clinical and biological evaluation included clinical assessment every 6 weeks and determination of CD4 cell count and HIV-RNA concentration every 3 months. RESULTS: Median length of follow-up on triple therapy was 15 months (range: 7-21 months). Neither progression in the CDC classification nor death occurred. No significant change in mean weight SD scores was noted when baseline values were compared with values obtained after 1 year of triple therapy. Median CD4 count increases were of 210 x 10(6)/l, 415 x 10(6)/l, and 472 x 10(6)/l cells at 6, 12, and 18 months, respectively. Among the patients baseline characteristics, neither age nor initial CD4 cells count influenced the magnitude of immunologic improvement. There were median decreases of 1.14, 0.95, and 1.5 log10 per ml of plasma in the concentration of viral RNA at 6, 12, and 18 months respectively. Seven patients maintained an undetectable viral load when under treatment. The introduction of at least one new reverse transcriptase inhibitor at the initiation of triple therapy correlated significantly with a greater viral suppression. CONCLUSION: Despite variable viral response, antiretroviral-experienced HIV-infected children demonstrated a substantial CD4 cell increase during a median period of 15 months of ritonavir containing combination therapy.

Adolescent↗
PubMed1999

Preliminary report of a toxicity study of hydroxyurea in sickle cell disease. French Study Group on Sickle Cell Disease.

AIM: To evaluate the tolerance of hydroxyurea in children affected with sickle cell disease. DESIGN: Questionnaire study of French physicians likely to treat patients with sickle cell disease. Data were collected on 101 children with sickle cell disease, treated for a median of 22 months, 36 of whom were treated for more than three years. 13 children were younger than 5 years of age at inclusion. RESULTS: Hydroxyurea was stopped for medical reasons in 11 patients: 6 failures, 1 pregnancy, 1 cutaneous rash, 1 leg ulcer, 1 lupus. Acute lymphoblastic leukaemia occurred in a girl treated for 1.5 months with hydroxyurea, this short interval arguing against a causative association. One 17 year old boy had paraparesis after 8 years of treatment. CONCLUSIONS: No major short or medium term toxicity was related to hydroxyurea in this cohort of 101 children. However, the number of children treated for more than 3 years is too few to make firm conclusions on the long term tolerance of this drug.

Adolescent↗