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Biomedical subjects

P Quartier

Publications and source records attributed to P Quartier.

34 records · Page 2Linked to original sources
PubMed2001

Chimaeric anti-CD20 monoclonal antibody (rituximab) in post-transplant B-lymphoproliferative disorder following stem cell transplantation in children.

Post-transplant lymphoproliferative disorder (PTLD) after haemopoietic stem cell transplantation is a serious complication that occurs in 8-22% of patients with high-risk factors. We retrospectively investigated tolerance and efficacy of humanized anti-CD20 monoclonal antibody (rituximab) as first-line treatment in 12 children with B-cell PTLD. At diagnosis, eight patients had tumoral involvement. The other four patients had fever, associated with raised Epstein-Barr virus (EBV) viral load and monoclonal gammopathy. Rituximab was given at the dose of 375 mg/m2 once a week by intravenous infusion (1-9 infusions). Only 1/48 infusions was associated with a grade 2 clinical adverse event. Eight out of 12 (66%) patients responded to the treatment and were in complete remission. All patients without tumoral involvement responded to the treatment. A rapid decrease in fever within 1 week was observed in all responders. Non-responders did not show any clinical response during the first week. Tumoral involvement and immunodepression seemed to be more marked in non-responders. Rituximab was an effective and well-tolerated treatment of B-cell PTLD. Early treatment before tumoral involvement seemed to be the most effective approach. Lack of rapid response should lead to intensification of PTLD treatment. Pre-emptive treatment should be considered and evaluated in further longitudinal multicentre studies.

Antibodies, Monoclonal↗
PubMed2001

[T-cell-depleted HLA non-identical bone marrow transplantation in the child: prevention of graft-versus-host reaction by administration of donor T lymphocytes alloreactive against the recipient].

The success of HSCT from HLA partially disparate donors depends on the development of new strategies able to efficiently prevent GVHD and to protect patients from infections and relapse. Using an immunotoxin (IT) directed against the alpha-chain (p55) of the human IL-2r (RFT5-SMPT-dgA), we have previously shown that it is possible to kill mature T cells activated towards a specific HLA complex by a one-way MLR. We designed a clinical trial assessing the effect of infusing increasing doses of T lymphocytes in the setting of children recipients of non HLA genetically identical HSCT. Thirteen patients have been enrolled from September 1998 to April 2000 and fourteen HSCT have been realized in 13 patients (pts). Donors were MUD in 3 cases and familial HLA partially disparate in the remaining cases. Allodepleted donor T cells were injected between day +14 and day +30 provided that ATG was undetectable in the serum and blood PMN counts was > 500/microliter. The mean age of these patients was 17 months (range 1 to 42). Diagnosis included immune deficient and malignant hemopathies. Three patients received 1 x 10(5) allodepleted T cell/kg, 7 patients received 4 x 10(5)/kg and 4 patients received 6 x 10(5)/kg allodepleted T cells. Full inhibition of MLR was achieved in 12 out of 14 cases. In two cases, a residual T cell reactivity to the recipient was observed (4 to 5%) and patients developed grade II aGVHD. aGVHD occurred in 4 out of 11 grafted patients (all grade II). No chronic GVHD has developed, so far. Three patients died from severe VOD or PHT at day +34, day 51 and day +166, while one infected patient by VZV, CMV and EBV before HSCT died 6 months after transplantation from meningoencephalitis and another patient died from relapse at day +291. The patient for which there was no engraftment died at day +48 from staphylococcus infection. Overall survival is 54%, with a median follow up of 8 months; the mean time to reach a blood lymphocyte count > 500 was 41 days, to reach a CD3 count > 300 microliters 63 days (20-111), CD4 > 200 microliters 97 days and positive mitogen-induced proliferation 90 days. In three patients, a tetanus-toxoid positive proliferation was detected before immunization. From this intermediate analysis, we conclude that 1) specific allodepletion is an effective approach to prevent aGVHD in a haploincompatible setting, 2) data on immunological reconstitution suggest that infused T cells do survive and expand. A higher number of patients must be enrolled to determine the optimal number of T cells to infuse.

Acute Disease↗
PubMed2000

The incidence of clonal T-cell receptor rearrangements in B-cell precursor acute lymphoblastic leukemia varies with age and genotype.

B-cell precursor acute lymphoblastic leukemias (BCP-ALLs) are increasingly treated on risk-adapted protocols based on presenting clinical and biological features. Residual molecular positivity of clonal immunoglobulin (IG) and T-cell receptor (TCR) rearrangements allows detection of patients at an increased risk of relapse. If these rearrangements are to be used for universal follow-up, it is important to determine the extent to which they are informative in different BCP-ALL subsets. We show that IGH V-D-J rearrangements occur in 89% of 163 BCP-ALL, with no significant variation according to age or genotype (BCR-ABL, TEL-AML1, MLL-AF4, and E2A-PBX1). In contrast, TCRG rearrangements, which occur in 60% of patients overall, are frequent in BCR-ABL and TEL-AML1, are less so in MLL-AF4, and are virtually absent in infants aged predominantly from 1 to 2 years and in E2A-PBX1 ALLs. Incidence of the predominant TCRD Vdelta2-Ddelta3 rearrangement decreases with age but is independent of genotype. These differences are not due to differential recombination activating gene activity, nor can they be explained adequately by stage of maturation arrest. Analysis of MLL-AF4 BCP-ALL is in keeping with transformation of a precursor at an early stage of ontogenic development, despite the adult onset of the cases analyzed. We postulate that the complete absence of TCRG rearrangement in E2A-PBX1 cases may result from deregulated E2A function. These data also have practical consequences for the use of TCR clonality for the molecular follow-up of BCP-ALL.

Adolescent↗
PubMed2000

[Lymphomas in children infected with HIV-1].

PURPOSE: To describe the features of lymphoma in human immunodeficiency virus (HIV)-infected children, their treatments and the outcome of patients. RESULTS: We analyzed seven HIV-infected children (four by mother-to-child transmission and three by transfusion) (25 months to 18.5 years old) with lymphoma (one Hodgkin's disease and six non-Hodgkin's lymphomas). All of them presented with a severe immunodepression and a high viral load. Five of six were high grade-B cell non-Hodgkin's lymphoma of large-cell histologies (immunoblastic or centroblastic). Five were extranodular disease and three were metastatic at diagnosis. Epstein-Barr virus was detected in four tumors. Five of seven received a multiagent chemotherapy. Toxicity was high. Treatment for the skin T lymphoma consisted of radiation therapy. Five children were complete responders (with survival three years, 2.5 years, 12, 18 and 18 months) and two died of progression of lymphoma (four and five months later). CONCLUSION: Incidence of lymphoma is increased in HIV-infected children. Anticancer chemotherapy regimens that include aggressive supportive care and concomitant antiretroviral therapy or immunotherapy may yield high survival rates.

Adolescent↗
PubMed2000

Relapses of childhood anaplastic large-cell lymphoma: treatment results in a series of 41 children--a report from the French Society of Pediatric Oncology.

PURPOSE: To study response to chemotherapy and the outcome of children treated for a relapsed anaplastic large-cell lymphoma (ALCL) and to evaluate the role of bone marrow transplantation (BMT) in these patients. PATIENTS AND METHODS: Clinical data concerning the 41 relapses that occurred in 119 patients with ALCL enrolled in 3 consecutive studies since 1975 were analysed. First-line treatment consisted of intensive chemotherapy according to the COPAD protocol for the first series of 12 patients treated between 1975 and 1989 and to the SFOP (French Society of Pediatric Oncology) HM protocols for the 30 patients treated between 1989 and 1997. Twenty-eight patients were treated with CV(B)A (CCNU, vinblastine, ara-C with or without bleomycin), and the others with miscellaneous protocols for recurrent disease. Fifteen patients underwent autologous BMT and 1 allogeneic BMT while in CR2. RESULTS: Thirty-six of forty-one (88%) patients achieved CR2. With a median follow-up of 5 years, 12 patients died, 9 of their disease and 29 patients are alive in CR2 (20 patients), CR3 (5 patients), CR4 (2 patients), CR5 (1 patient) or CR6 (1 patient). Overall and disease-free survival are respectively 69% (53%-82%) and 44% (29%-61%) at three years. In univariate analysis, patients treated with ABMT while in CR2 did not appear to have a better outcome than the other. Remarkably, a long-lasting remission was obtained in 8 of 13 patients treated with weekly vinblastine for a relapse including 6 relapses occurring after ABMT. CONCLUSIONS: Relapsed ALCL are highly chemosensitive but over 40% of the patients experience several relapses. Prolonged conventional chemotherapy based on vinblastine might, in some cases, be as efficient as short intensive treatment with ABMT.

Adolescent↗
PubMed2000

Humanized anti-CD20 monoclonal antibody (Rituximab) in post transplant B-lymphoproliferative disorder: a retrospective analysis on 32 patients.

BACKGROUND: B-lymphoproliferative post-transplant disorder (BLPD) is a severe complication of organ and bone marrow transplantation. The reduction of immuno-suppressive therapy or surgery for localized disease may cure some BLPDs. Other therapeutic approaches such as chemotherapy and antiviral drugs are toxic and of limited efficacy. Adoptive immunotherapy with donor T-cell infusions has yielded promising results but is, at the present time, easily applicable only in bone marrow-transplanted patients. Anti-B-cell Murine monoclonal antibodies (MoAbs) have proven effective but are no longer available for human use. We report the activity of a humanized anti CD 20 Mo Ab (Rituximab-MABTHERA Roche) in 32 episodes of BLPD treated in 14 French centers. PATIENTS AND METHODS: Between November 1997 and September 1998, 32 patients were diagnosed with BLPD. Twenty-six patients had undergone solid organ transplants (liver 8, kidney 8, heart 4, lung 3, heart lung 1, kidney-pancreas 1, liver-kidney 1) and six patients had received bone marrow transplantations. The median age of the patients was 34 years (3-67 years) and the median delay between graft and tumor 5 months (1-156 months). In organ recipients, tumors were classified as polymorphic and monomorphic in 10 and 15 cases, respectively; 4 of 6 bone marrow transplant recipients were treated without pathology documentation because of a rise in EBV load, fever and lymph node enlargement. Tumors were associated with EBV in 22 of 26 tested cases. Rituximab was used as first-line therapy in 30 patients (after reduction of immunosuppressive treatment in 27 patients) and as salvage therapy in 2 patients (after failure of chemotherapy). The median time from diagnosis of BLPD to treatment with Rituximab was 14 days (1-110 days). Two patients received eight infusions, twenty-six patients four infusions, one patient three infusions and three patients two infusions of 375 mg/m2. RESULTS: The tolerance of rituximab was good. The overall response rate was 69%, with 20 complete responses and 2 partial responses. In solid organ transplant the response rate was 65% (15 CR and 2 PR) while it was 83% in bone marrow-transplanted patients (5 CR). With a median follow-up of 8 months (1-16 months) 24 patients are still alive. The one-year projected survival is 73%. Of the 22 patients who achieved response, 15 patients (11 solid organ transplant and 4 bone marrow transplant) are alive with no evidence of disease, 4 patients relapsed a median of 7 months (3-10 months) after treatment and 3 died while in CR of concurrent diseases. Of the 10 patients who did not respond to Rituximab 5 are alive with no evidence of disease after salvage therapy. CONCLUSIONS: The use of rituximab appears to be a safe and relatively efficient therapy in BLPDs. The results need to be confirmed in a prospective multicentric trial.

Adolescent↗
PubMed1999

Early and prolonged intravenous immunoglobulin replacement therapy in childhood agammaglobulinemia: a retrospective survey of 31 patients.

OBJECTIVE: To evaluate the outcome of children who received prolonged intravenous immunoglobulin (IVIg) replacement therapy early in life for X-linked agammaglobulinemia (XLA). STUDY DESIGN: We performed a retrospective study of the clinical features and outcome of patients with genetic and/or immunologic results consistent with XLA. Patients receiving IVIg replacement therapy within 3 months of the diagnosis and for at least 4 years between 1982 and 1997 were included. RESULTS: Thirty-one patients began receiving IVIg replacement therapy at a median age of 24 months and were followed up for a median time of 123 months. IVIg was given at doses >0.25 g/kg every 3 weeks, and mean individual residual IgG levels ranged from 500 to 1140 mg/dL (median, 700 mg/dL). During IVIg replacement, the incidence of bacterial infections requiring hospitalization fell from 0.40 to 0.06 per patient per year (P <. 001). However, viral or unidentified infections still developed, including enteroviral meningoencephalitis (n = 3) causing death in one patient, exudative enteropathy (n = 3), and aseptic arthritis (n = 1). At last follow-up, 30 patients were alive at a median age of 144 months (range, 58 to 253 months). Among 23 patients who were evaluated by respiratory function tests and computed tomography, 3 had an obstructive syndrome, 6 had bronchiectasis, and 20 had chronic sinusitis. CONCLUSION: Early IVIg replacement therapy achieving residual IgG levels >500 mg/dL is effective in preventing severe acute bacterial infections and pulmonary insufficiency. More intensive therapy may be required to fully prevent the onset of bronchiectasis, chronic sinusitis, and nonbacterial infections, particularly enteroviral infections, in all cases.

Agammaglobulinemia↗
PubMed1997

Germ-line transcription and methylation status of the TCR-J alpha locus in its accessible configuration.

We have generated two in vivo mouse models to study the regulation of DNA accessibility to the V(D)J recombinase machinery in the T cell receptor (TCR)-J alpha locus. In recombination activating gene (RAG)-deficient mice, both injection of a TCR-beta chain transgene (RTB mice) or anti-CD3-epsilon treatment in vivo (RT3 mice) lead to the same phenotype with homogeneous thymocyte populations blocked at the CD4+ CD8+ double positive (DP) stage. At this developmental stage, the TCR-alpha rearrangements are about to start, and the TCR-J alpha locus is frozen in an accessible but yet unrearranged configuration in these mice. We show high level of TCR-alpha germ-line transcription in thymocytes from RTB and RT3 mice. Transcripts are skewed towards the 5' end of the TCR-J alpha locus, and the T early alpha (TEA) sterile transcript is predominant and therefore provides a useful marker for the TCR-J alpha locus opening. Analysis of the DNA methylation status reveals a global surmethylation of the TCR-J alpha locus in the thymus in comparison with non-lymphoid cells in these mice. We propose that hypermethylation of the locus could precede a progressive demethylation, providing a specific protective and regulatory role in the rearrangement events.

Animals↗
PubMed1996

[Early diagnosis and treatment of cytomegalovirus polyradiculoneuritis in a child infected by HIV].

BACKGROUND: Axonal polyradiculopathy due to cytomegalovirus (CMV) in AIDS has been reported in adults but it is not well documented in children. OBJECTIVE: We describe the elements of diagnosis and the outcome after anti-CMV therapy in a pediatric case. CASE REPORT: A 11-year-old boy with post-transfusional AIDS and low CD4 count (< 50/mm3) suffered from bilateral leg pain and weakness progressing within 15 days to paraplegia and cauda equina syndrome. Electromyography showed pure axonal neuropathy. Examination of the CSF showed increased proteins, low glucose concentration, neutrophilic pleiocytosis and positive detection of CMV by polymerase-chain reaction. The CMV viremia was positive. Treatment with ganciclovir and foscarnet allowed dramatical clinical improvement. Retinitis occurred during the maintenance therapy and was cured after reintroduction of the initial doses of ganciclovir and foscarnet. The child died five months later from a bacterial pneumopathy. CONCLUSIONS: Children with advanced AIDS may benefit from early recognition and treatment of CMV polyradiculopathy. The interactions and cumulated toxicities between anti-CMV and anti-retroviral drugs must be considered. The prognosis remains poor for CMV neuropathy due to the severe immunodepression caused by the HIV infection.

AIDS-Related Opportunistic Infections↗
PubMed1993

[Massive fetomaternal hemorrhage and prevention of fetomaternal Rhesus incompatibility. The failure of our present system of prevention].

We had a case where risk of rhesus D feto-maternal immunisation occurred following failure to diagnose feto-maternal haemorrhage (HFM); and it was shown up by rhesus negative mother with a rhesus positive fetus being diagnosed as having has a massive HFM only three days after delivery. Giving the mother the standard dose of Anti-D immunoglobulin without a previous test to find out how serious the HFM was showed that we do not test for this normally. So it seems to us necessary when considering prophylaxis of rhesus D immunisation to go back to first principles and carry out Kleihauer's test particularly when neonatal anaemia is found in the child.

Adult↗
PubMedDate not supplied

The French version of the Childhood Health Assessment Questionnaire (CHAQ) and the Child Health Questionnaire (CHQ).

We report the results of the cross-cultural adaptation and validation into the French language of two health status instruments. The Childhood Health Assessment Questionnaire (CHAQ) is a disease specific instrument that measures functional ability in daily living activities in children with juvenile idiopathic arthritis (JIA). The Child Health Questionnaire (CHQ) is a generic health related quality of life instrument designed to capture the physical and psychosocial well-being of children independently from the underlying disease. Five hundred children were enrolled including 306 patients with JIA classified into systemic (23%), polyarticular (22%), extended oligoarticular (25%), and persistent oligoarticular (30%) subtypes, and 194 healthy children. Both instruments were reliable with intra-class correlation (ICC) coefficients for the test-retest procedure of 0.91 for the CHAQ, and 0.87 and 0.89 for the physical and psychosocial summary scores of CHQ, respectively. Agreement between parents and children evaluated for the CHAQ was high with an ICC of 0.89 for the disability index; weighted kappa coefficients for the 8 domains ranged from 0.61 to 0.72. Convergent validity was demonstrated by significant correlations with the JIA core set of variables (physician and parent global assessment, scores for active joints and joints with limited range of motion, erythrocyte sedimentation rate) for both instruments. Both CHAQ and CHQ discriminated between healthy and JIA children, but only the disease specific CHAQ questionnaire discriminated clearly between the 4 JIA subtypes. In conclusion, the French versions of the CHAQ and the CHQ are reliable, and valid health assessment questionnaires to be used in children suffering from JIA.

Adolescent↗