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M Kuentz

Publications and source records attributed to M Kuentz.

At least 55 records · Page 3Linked to original sources
PubMed1998

Treatment-related deaths and second cancer risk after autologous stem-cell transplantation for Hodgkin's disease.

Autologous stem-cell transplantation has become a widely used therapy in Hodgkin's disease (HD). To appreciate the early and late risks associated with this procedure, its lethal toxicity and effects on the incidence of secondary cancers were studied. Data related to 467 French patients grafted from 1982 to 1995 for primary sensitive disease (PSD, 22%), primary refractory disease (PRD, 18%), first relapse (R1, 45%), or subsequent relapses (R2, 15%) were analyzed. Grafted patients (PSD, PRD, and R1; n = 393) were matched (3 controls for 1 case) on age, gender, clinical stage, B symptoms, and time at risk with 1179 conventionally treated patients issued from international databases. The proportional hazards (Cox) model was used to assess relative risks (RR). Among grafted patients, 8% died of toxicity related to the procedure, and 18 secondary cancers occurred leading to a 5-year cumulative incidence rate of 8.9%. In this series, risk factors for second cancer were age >/=40 years (RR = 3.73, P = .007) and the use of peripheral blood stem cells as source of graft (RR = 3.10, P = .03). Among grafted and matched ungrafted patients, risk factors for the development of secondary cancer were age >/=40 years (RR = 2.90, P < .001), relapse versus no relapse (RR = 5.22, P = .006), PRD versus other patients (RR = 3.86, P = .033), and grafted versus ungrafted patients (RR = 2.04, P = . 024). Solid tumors were more frequent in grafted than in ungrafted patients (RR = 5.19, P = .001) although the incidence of myelodysplasia and acute myeloid leukemia was similar in the two groups. We conclude that high-dose chemotherapy administered as first-line treatment or after relapse is associated with an acceptable toxic death rate. The risk of secondary myelodysplasia or acute myeloid leukemia is not significantly increased after autologous stem-cell transplantation for HD, whereas an increased risk of solid tumors exists. The peripheral blood stem-cell-associated risk of secondary cancer among grafted patients needs further investigations.

Adolescent↗
PubMed1998

Platelet transfusion: a dose-response study.

Early recommendations on prophylactic transfusion of thrombocytopenic patients involved a standard platelet dose of about 0.5 x 10(11)/10 kg body weight. Given the lack of data supporting this dose, we prospectively studied the dose response to platelet transfusions in adults and children with hematologic malignancies. Each patient received, in similar clinical conditions, a medium, high, and very high dose of fresh (< 24 hours old) ABO-compatible platelets, in the form of apheresis platelet concentrates (APC). For the adults, the medium dose was defined as APC containing between 4 and 6 x 10(11) platelets, the high dose between 6 and 8 x 10(11), and the very high dose > 8 x 10(11); for the children, the three doses corresponded to 2 to 4, 4 to 6, and > 6 x 10(11) platelets. The end points were the platelet increment, platelet recovery, and the transfusion interval, and the results were compared with a paired t-test. Sixty-nine adults and 13 children could be assessed. Recoveries in the adults were similar with the three doses (from 28% to 30%), but the high and very high doses led to a significantly better platelet increment (52 and 61 x 10(9)/L, respectively) than the medium dose (33 x 10(9)/L, P < .01). The main difference was in the transfusion interval, which increased with the dose of platelets transfused, from 2.6 days with the medium dose to 3.3 and 4.1 days with the high and very high doses, respectively (P < .01). The positive effect of the high dose was observed regardless of pretransfusional clinical status, but was more marked in patients with no clinical factors known to impair platelet recovery. In these patients, a platelet dose of 0.07 x 10(11) per kg of body weight led to a transfusion interval of more than 2 days in 95% of cases. In patients with clinical factors favoring platelet consumption, the proportion of transfusions yielding an optimal platelet increment and transfusion interval increased with the dose of platelets. The platelet dose-effect was also significant in the children, in whom the high and very high doses led to 1.5-fold to twofold higher posttransfusion platelet counts and transfusion intervals. We conclude that transfusion of high platelet doses can reduce the number of platelet concentrates required by thrombocytopenic patients and significantly reduce donor exposure.

Acute Disease↗
PubMed1998

Apparent reactivation of a red cell alloantibody in a healthy individual after G-CSF administration.

Granulocyte-colony stimulating factor (G-CSF) has been successfully administered to healthy subjects to mobilize peripheral blood stem cells (PBSC) for allogeneic transplantation. Adverse events are moderate. We report the first case of apparent reactivation of an alloantibody to a blood cell antigen (Jk(a)) after G-CSF administration to a healthy subject and its transmission to the PBSC transplant recipient; no concomitant reactivation of other alloantibodies was detected. This case raises questions on the effect of G-CSF on the immune system and its safety in healthy individuals.

Adjuvants, Immunologic↗
PubMed1998

Modified Young's modulus of microcrystalline cellulose tablets and the directed continuum percolation model.

The purpose of this investigation was to analyze the modified Young's modulus of microcrystalline cellulose tablets at comparatively low relative densities, based on concepts of percolation theory. Tablets were prepared and tested using a Zwick 1478 universal testing instrument. For statistical evaluation a new method is introduced for power laws, which exhibits highly correlated model parameters. According to our results the model Leuenberger, Leu is consistent with an Effective Medium Approximation which exhibits an exponent equal to one far away from the percolation threshold. In addition, the results show that it is essential to evaluate the elastic behavior of tablets close to the percolation threshold. For the different types of MCC a critical exponent q = 3.95 +/- 0.14 was obtained. This result is very essential, as it is in good agreement with the theoretically expected value of 3.9 from an elastic network (central force model). The proposed model describes the modified Young's modulus better than former model equations taking into account the relative density. Thus, the process during uniaxial compaction can be imagined as a directed continuum percolation and the relative density of compacts can be identified as a space-occupation probability density phi yielding reasonable percolation thresholds.

Cellulose↗
PubMed1997

Predictive value of host-specific donor helper T-cell precursor frequency for acute graft-versus-host disease and relapse in HLA-identical siblings receiving allogeneic bone marrow transplantation for hematological malignancies.

BACKGROUND: Acute graft-versus-host disease (aGVHD) is still one of the main causes of morbidity and mortality after allogeneic bone marrow transplantation. Attempts to avoid GVHD are associated with an increased risk of relapse, probably because the graft-versus-leukemia effect is also abrogated. It was recently suggested that a high frequency of host-specific donor helper T cell precursors (HTLp) might be predictive of significant aGVHD (grade > or = II). METHODS: We retrospectively studied the frequency of HTLp by means of simplified limiting-dilution analysis to determine its predictive value for aGVHD and relapse. Pre-bone marrow transplantation, host-specific donor HLTp frequencies were analyzed in 32 patients who had received marrow from HLA-identical siblings for hematological malignancies, in terms of aGVHD and relapse. RESULTS: HTLp frequencies were significantly higher in patients who had aGVHD > or = grade II (n=14) than in those without aGVHD (n=18) (P=0.007). Patients who relapsed (n=13) had significantly lower HTLp frequencies than those who did not relapse (n=19) (P<0.0001). The probabilities of relapse (Kaplan-Meier method) when the HTLp frequency was higher and lower than 1/200,000 were 0% and 88%, respectively (P<0.0001). CONCLUSIONS: The definition of HTLp cut-off values predictive of aGVHD and relapse should contribute to donor selection and could open the way to protocols adapting immunomodulation to the likely risk of aGVHD and relapse.

Adolescent↗
PubMed1997

Serum Aspergillus galactomannan antigen testing by sandwich ELISA: practical use in neutropenic patients.

The double sandwich ELISA detecting Aspergillus galactomannan (GM) was prospectively evaluated for the diagnosis of invasive aspergillosis (IA) in 50 haematological patients at risk for IA. Serum samples were collected once weekly as long as the risk factors persisted. Six patients had proven or probable IA (3 A. fumigatus, 1 A. flavus, 1 A. niger, 1 A. ustus) and the GM titres were parallel to the clinical evolution of IA. Six of nine patients with suspected IA had at least two consecutive serum GM titres above 1 ng/ml and died with increasing titres, whereas the GM-negative patients survived. Positive GM titres did not anticipate the isolation of fungi. Unfortunately, positive GM titres did not anticipate the initiation of antifungal therapy, based on clinical suspicion. Moreover, if a true-positive result was defined as two consecutive positive serum samples, four patients out of 35 without proven, probable or suspected IA were positive. Then, the rate of false-positive results was high (12%) in the range previously reported. Nevertheless, the GM ELISA appears useful to assess IA and to follow the efficacy of antifungal treatment.

Adolescent↗
PubMed1997

Fatal primary cutaneous aspergillosis in a bone marrow transplant recipient: nosocomial acquisition in a laminar-air flow room.

A case of primary cutaneous aspergillosis occurring in an allogeneic bone marrow transplant recipient in a laminar airflow room is reported. The patient developed grade III graft-versus-host-disease and epidermolysis. Although the patient had remained in his laminar airflow room from the graft onward, he subsequently developed primary cutaneous aspergillosis. The aspergillosis became invasive and the patient died. The patient was probably contaminated by air containing conidia when he left the sterile room for endoscopy, and the fluidized bed used may have contributed to the local development of the disease. This nosocomial aspergillosis stresses the necessity of performing invasive procedures under laminar airflow protection to prevent Aspergillus contamination in immunocompromised hosts at risk for aspergillosis.

Adult↗
PubMed1997

Early allogeneic transplantation favorably influences the outcome of adult patients suffering from acute myeloid leukemia. Société Française de Greffe de Moelle (SFGM).

Allogeneic BMT for patients with acute myeloid leukemia (AML) is presently a reference therapy. The indications for this therapy mainly rely upon prognostic factors, and their importance is constantly reassessed. To examine the impact of time from diagnosis to transplant on survival and leukemia-free survival (LFS), we analyzed 109 patients from the database of the SFGM comprising patients who had all received an HLA-identical allogeneic BMT for a diagnosis of AML in first complete remission (CR1) between January 1987 and December 1992. All patients were conditioned with cyclophosphamide (CY) and total body irradiation (TBI) (CYTBI), and methotrexate (MTX) + cyclosporin A (CsA) were used as graft-versus-host disease (GVHD) prophylaxis. Patient characteristics were: age = 33 +/- 9, M/F = 64/45, white blood cell count (WBC) at diagnosis = 27 +/- 42 x 10(9)/l, FAB distribution: M1 and M2 = 55; M3 = 15, M4 and M5 = 33, M0, M6 and M7 = 6. Karyotyping was carried out for 64 patients: 32 had a normal karyotype, 16 had good prognosis abnormalities (t(8;21), t(15;17), inv 16) and 16 patients had other abnormalities. Eleven patients needed two courses of induction to achieve CR. Time between diagnosis and BMT was 120 (64-287) days. Forty-nine patients developed grade > or = 2 acute GVHD (actuarial probability = 46%). With a median follow-up of 50 months (27-100), the 5-year probabilities for transplant-related mortality (TRM), relapse, overall survival and LFS are respectively 25%, 26%, 59% and 55%. A multivariate analysis showed that survival is adversely influenced by three independent factors: time to transplant (> 120 days vs < or = 120 days), acute GVHD (grade 2-4 vs grade 0-1) and age (> 33 vs < or = 33). LFS is only influenced by the first two of these factors. The favorable impact of a shorter time from diagnosis to transplant should lead to performing the transplant as early as possible. Practically speaking, this means that when such therapy is chosen for a patient with CR1 AML, the search for an allogeneic donor should begin immediately and transplant be performed as soon as possible.

Acute Disease↗
PubMed1996

Factors influencing outcome in de novo myelodysplastic syndromes treated by allogeneic bone marrow transplantation: a long-term study of 71 patients Société Française de Greffe de Moelle.

We report on 71 consecutive patients with de novo myelodysplastic syndromes referred to physicians belonging to the Société française de greffe de moelle from 1982 through 1991 and transplanted with marrow from HLA-identical siblings. There were 16 cases of refractory anemia, 27 of refractory anemia with excess of blast cells, and 28 of refractory anemia with excess of blast cells in transformation. Seventeen patients had received cytoreductive chemotherapy before the graft. The disease progressed in 17 patients between diagnosis and grafting. Twenty-three patients are alive with a median follow-up of 6 years, whereas 24 died from relapse and 24 from transplant-related complications. Kaplan-Meier estimates of event-free survival, relapse and transplant-related mortality at 7 years were 32%, 48%, and 39%, respectively. The log-rank test and Cox's model revealed better outcome among young patients, patients in an early stage of the French-American-British (FAB) classification or with a low percentage of marrow blasts before transplantation, patients who did not undergo cytoreductive chemotherapy before transplantation, and patients conditioned with total body irradiation and cyclophosphamide. The high rate of relapse in advanced FAB stages has led us to graft patients earlier in the course of the disease, and we are currently conducting a multicenter, randomized study to determine the value of intensive chemotherapy before grafting in patients with an excess of marrow blasts.

Adult↗
PubMed1995

Successful engraftment after autologous transplantation of 10-day cultured bone marrow activated by interleukin 2 in patients with acute lymphoblastic leukemia.

Disease recurrence remains the major problem in autologous bone marrow transplantation (BMT) for hematologic malignancies. To improve the therapeutic efficiency of autologous BMT, we investigated the use of autologous marrow activated in vitro with interleukin 2 (IL-2) to generate killer cells for in vivo purging. A feasibility trial was initiated in 5 patients with poor prognosis acute lymphoblastic leukemia, who were transplanted, after marrow ablative therapy, with autologous marrow cultured for 10 days with 10(3) units of IL-2/ml. A highly significant increase in NK activity and an induction of LAK activity were observed after incubation. Patients received 0.64 to 1.56 X 10(8) cultured BM cells/kg and 1.87 to 44.8 x 10(4) CFU-GM/kg. Four patients engrafted and achieved granulocyte counts > 0.5 x 10(9)/l on days 35, 24, 36 and 22 after transplant. Three of these patients showed platelet recovery to > 50 x10(9)/l on days 25, 42 and 40 after transplant. One patient remained thrombocytopenic until relapse. One patient died on day 12 after transplant. This study demonstrates that cultured BM activated with IL-2 can be used successfully for hematological rescue in the clinical setting.

Bone Marrow↗
PubMed1995

Late toxoplasmosis evidenced by PCR in a marrow transplant recipient.

We report a case of disseminated toxoplasmosis occurring 12 months after allogeneic BMT. The patient was seropositive for Toxoplasma gondii, and the donor was seronegative, so the patient was given anti-Toxoplasma prophylaxis. One year after BMT, he developed fever and muscle pain without other clinical symptoms. PCR amplification for T. gondii performed on blood was positive. Toxoplasma were found in bronchoalveolar lavage by PCR and in the marrow by special stains. With treatment, the PCR signal disappeared in 3 days while clinical symptoms resolved over 15 days. This case emphasizes the possibility of late toxoplasmosis after BMT despite prophylatic treatment, and the value of PCR in making the diagnosis.

Adult↗
PubMed1994

Thrombocytopenia after bone marrow transplantation caused by a recipient origin Br(a) allo-antibody: presence of mixed chimerism 3 years after the graft without hematologic relapse.

We report a case of mild, clinically asymptomatic, immune thrombocytopenia after allogenic bone marrow transplantation (BMT) for chronic myeloid leukemia (CML) caused by the presence of a recipient-origin Br(a) antibody that recognized the donor platelets. Although the antibody titer decreased, it remained detectable more than 3 years after BMT. Chimerism studies were performed combining cytogenetics, blood cell phenotype studies, and genomic amplification of hypervariable sequences. Cytogenetic studies and molecular analysis of peripheral blood cells, purified B- and T-lymphocyte subpopulations, and bone marrow colonies showed the hematopoiesis to be of donor origin, but absorption-elution experiments with peripheral RBCs showed a small amount of recipient RBCs. The CML chimeric transcript was also detected by means of polymerase chain reaction on samples collected until day +867 post-BMT. This case shows that recipient-origin platelet alloantibodies can cause thrombocytopenia after BMT and that the persistence of small numbers of recipient cells (even leukemic) is not necessarily associated with hematologic relapse.

Adult↗
PubMed1994

Hepatitis C virus infection and allogeneic bone marrow transplantation.

Serum antibodies to hepatitis C virus (HCV) were tested for inpatients undergoing allogeneic BMT to determine the risk of acquiring HCV infection and the role of HCV in posttransplant liver complications. The HCV seroconversion rate was evaluated according to the date of BMT and blood donor screening at the time. Anti-HCV antibodies (anti-HCV) were detected with a second-generation ELISA and confirmed with a second-generation radioimmunoblot assay. All patients received leukocyte-depleted blood products and most received apheresis platelet concentrates. One hundred twenty of 181 consecutive patients transplanted from January 1987 to December 1991 were anti-HCV-negative before BMT, had at least 6 months of follow-up, and were thus evaluated for the seroconversion rate. Before screening for non-A, non-B hepatitis, 14% of the patients seroconverted to HCV (0.44% per unit transfused). After introduction of screening for alanine aminotransferase and antibodies to hepatitis B core antigen the risk of seroconversion was 4% per patient (0.26% per unit). When, in addition, blood was screened for anti-HCV the risk fell to 1.6% (0.03% per unit). Positive anti-HCV status before and after BMT was not predictive of veno-occlusive disease, liver graft-versus-host disease (GVHD), or death due to liver dysfunction. In contrast, the risk of chronic hepatitis was significantly increased.

Adolescent↗
PubMed1994

Influence of clinical status on the efficiency of stored platelet transfusion.

The efficiency of stored platelet transfusion was evaluated in terms of clinical status in 141 thrombocytopenic patients. In a paired prospective study in which fresh platelets were used as controls, clinical efficiency was assessed on the basis of the ability to increase platelet count (recovery) and the time to the next transfusion (D). In 48 clinically stable patients, recovery of fresh and stored platelets was similar (47% and 41%, respectively) and the interval to the next transfusion was D4 and D3. In contrast, 27 patients who had bacterial infections showed significantly different recoveries (24%/5%) and the interval to the next transfusion was D3/D1 for fresh and stored platelets respectively. Similarly, in 16 patients who were treated concurrently with amphotericin B, 18 other patients with graft-versus-host disease, nine with splenomegaly and four with veno-occlusive disease (VOD), fresh platelets performed better than stored platelets, showing recoveries of 27%/18%, 29%/15%, 16%/3% and 15%/2%. Furthermore, the need for retransfusion within 24 h was significantly increased with stored platelets. In 19 patients with anti-HLA alloimmunization who were transfused with HLA-matched fresh and stored apheresis platelet concentrate (APC), efficiency was similar (38%/36% and D4/D3). This study indicates that the storage induces an impressive decrease in the in-vivo platelet recovery and survival in patients with certain clinical conditions.

Adult↗
PubMed1993

[Hematopoietic growth factor (GM-CSF) after autologous bone marrow transplantation. A randomized, double-blind, multicenter study in 91 cases of non-Hodgkin's malignant lymphomas].

To a great extent, the risks of autologous bone marrow transplantation are related to neutropenia. Although the efficacy of the recombinant human granulocyte-macrophage colony-stimulating factor (rhu GM-CSF) on neutrophil recovery has appeared in numerous open trials, only a few randomized studies have hitherto been published. Ninety-one patients with non-Hodgkin's malignant lymphoma treated with ablative chemotherapy followed by purged or unpurged bone marrow transplantation were entered in a placebo-controlled, double-blind randomized study; 44 patients received GM-CSF (E. coli) in doses of 250 micrograms/m2/day, and 47 received a placebo. Treatment was administered daily as continuous infusion started on the day of transplantation and pursued until the absolute number of neutrophils reached 0.5 x 10(9)/l during 7 days or, if this failed, during 30 days. The median time of neutrophil recovery was 14 days in patients on rhu GM-CSF and 21 days in patients on placebo (P < 0.0001). Patients who received a mafosfamide-purged bone marrow also had a rapid neutrophil recovery (median: 16 days versus 20.5 days; P = 0.013). The stay in hospital was shorter in the rhu GM-CSF group (median: 23 days versus 28 days; P < 0.05). No significant difference in the number of days with fever, infections, antibiotics administered and overall survival was detected between the two groups. The main toxicity ascribable to rhu GM-CSF was a capillary leakage syndrome found in 3 patients. Thus, after purged or unpurged autologous bone marrow transplantation rhu GM-CSF significantly reduces the duration of both neutropenia and hospital stay.

Adolescent↗