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Biomedical subjects

P Wacker

Publications and source records attributed to P Wacker.

At least 37 records · Page 2Linked to original sources
PubMed1998

Prognostic significance of sex in childhood B-precursor acute lymphoblastic leukemia: a Pediatric Oncology Group Study.

PURPOSE: In childhood B-precursor acute lymphoblastic leukemia (ALL), possible interactions among sex, time, and widely used prognostic factors (age, WBC count, and DNA index) were investigated for the first 5 years after diagnosis. PATIENTS AND METHODS: All eligible patients aged 1 to less than 22 years, registered between February 1986 and September 1994 in two B-precursor ALL studies from the Pediatric Oncology Group (POG), were included in the analysis. Cutpoints for age (3.0, 5.0, and 10.0 years), WBC count (10, 50, and 100 x 10(9)/L), and DNA index (DI; 1.16) were defined. Four time periods after diagnosis (years 1, 2, 3, and 4 and 5 combined) were selected for the study of prognostic significance over time. The cut-off date for analysis was April 1996. RESULTS: A total of 3,717 children (2,010 boys and 1,707 girls) were included in the outcome analysis. No major differences between the sexes were observed in age, duration of symptoms before registration, WBC count, hemoglobin level, platelet count, ploidy, presence of CNS disease at diagnosis, or induction failure rate. Event-free survival (EFS) differences between sexes became significantly different from 2 years following diagnosis. At 5 years, in all subsets analyzed, boys fared worse than girls, although not all differences were statistically significant. Major sex differences in EFS were observed in older children (10 to 22 years), in patients with intermediate WBC counts (10 to 50 x 10(9)/ L), and in children who fit both of these subgroups, in whom the 2-year EFS was almost 20% higher in girls than in boys, reaching a 38% difference at 5 years. CONCLUSION: This study shows an outcome interaction among sex, time, and commonly used prognostic variables. The important sex difference observed at 2 and 5 years suggests that more intensive consolidation and/or maintenance therapy in some boys with B-precursor ALL should be investigated.

Adolescent↗
PubMed1997

Surgery in patients with coronary artery disease--silent ischaemia during transurethral resection of tumors of prostate or bladder.

BACKGROUND: Asymptomatic episodes of myocardial ischemia in clinically stable patients seem to occur frequently and may hint at a worse prognosis. HYPOTHESIS: This study was undertaken to determine whether surgical patients with coronary artery disease (CAD) have a higher risk of cardiac ischemia during the perioperative period compared with the late postoperative period and compared with patients without CAD. METHODS: In all, 14 patients with and 14 patients without CAD were examined by Holter monitoring during the perioperative and three days later during the postoperative periods for the presence of ST-segment depression as a marker of silent myocardial ischemia. RESULTS: While patients without CAD did not show ST-segment depression, patients with CAD were found to have had 143 episodes of ST-segment depression, 49% in the perioperative and 51% in postoperative recordings. CONCLUSION: Though patients were asymptomatic with antianginal therapy, there were episodes of ST-segment depression indicating silent myocardial ischemia in patients with CAD. Surgical interventions such as transurethral resection of tumors of prostate or bladder did not produce an increase of ischemic burden registered by Holter monitoring.

Aged↗
PubMed1994

Right atrial thrombosis associated with central venous catheters in children with cancer.

Right atrial thrombosis (RAT) is infrequently diagnosed in children with cancer. Once RAT is documented, medical fibrinolysis or surgical thrombectomy is recommended. A RAT was documented in a child with lymphoma and was successfully lysed with recombinant tissue-type plasminogen activator. The case is presented and therapeutic options reviewed.

Antineoplastic Agents↗
PubMed1993

Conditioning the leukemic patient before allogeneic BMT: value of intensifying immunosuppression in the context of different levels of T lymphocyte depletion of the graft.

We have studied the value of additional immune suppression in BMT conditioning regimens in 45 patients with leukemia and 4 with myelodysplastic syndrome allografted between 1984 and 1991. A dose of 6 Gy total lymphoid irradiation (TLI) was delivered to 12 of 24 and 15 of 25 patients conditioned with 10 Gy and 12 Gy total body irradiation (TBI), respectively. Thirteen patients also received methylprednisolone (MP) before BMT to enhance immunosuppression. Differences in immunosuppression between the TBI with or without TLI or MP regimens and the influence of different levels of graft T cell depletion were measured in terms of transplant rejection, and complete versus mixed chimerism. The treatment-related complications were evaluated in terms of GVHD and incidence of pneumonitis. The overall transplant rejection rate was 6% (3 of 49). Complete chimerism was not significantly modified by increasing the TBI dose or by additional TLI (p > 0.10) but was more often seen in patients receiving MP given as pre-transplant immunosuppressor booster (p = 0.01). The incidence of GVHD was only influenced by the level of T cell depletion (p = 0.003). All 49 patients received a TBI lung dose in the range 9.5-10 Gy. A crude pneumonitis range of 19% (9 of 47 evaluable patients) was found. Neither the addition of TLI, MP nor the T cell depletion influenced the lung toxicity rate (p > 0.10) but pneumonitis was more frequent in patients with GVHD (p = 0.005).

Adolescent↗
PubMed1993

Adoptive immunotherapy for recurrent CML after BMT.

Three patients with CML who relapsed after transplantation with T-depleted BM from their HLA-identical siblings were treated with transfusions of donor peripheral blood mononuclear cells, in combination with (short) IFN alpha 2 therapy. CML was successfully controlled as shown by the complete disappearance of Philadelphia-positive metaphases within 90 days of treatment. This treatment appears to be very effective as neither bcr-abl transcripts nor markers specific for hematological cells of recipient origin could be detected by very sensitive PCR techniques. Two patients treated in chronic phase are without evidence of disease 300 and 360 days after treatment. The third patient, treated in accelerated phase, died with BM aplasia, 39 days following PBMC infusions. Failure to detect residual donor-derived granulocytes, as was the case in this patient prior to initiating adoptive immunotherapy, may indicate loss of donor-derived BM activity. This may help predict and possibly prevent the occurrence of life-threatening aplasia after successful clearance of malignant hematopoiesis.

Acute Disease↗
PubMed1992

Recombinant human erythropoietin in the treatment of infants with anaemia of prematurity.

Recombinant human erythropoietin (rHuEPO) was administered subcutaneously three times a week to 18 infants with the anaemia of prematurity at doses of 75, 150, 300, or 600 units/kg per week for 4 weeks, starting at 3-4 weeks of postnatal age. A significant and dose-dependent increase in reticulocyte count was observed from a mean baseline value of 71 x 10(9)/l to 200 x 10(9)/l after 3 weeks of therapy, compared with a change from 69 to 97 x 10(9)/l in 66 historical controls. The haematocrit value remained unchanged during rHuEPO treatment, whereas it steadily declined until 9 weeks of postnatal age in the controls. These effects were accompanied by a marked reduction in serum iron concentration and transferrin saturation in patients receiving standard-dose iron supplements, but not in those given larger doses. Only 3 of 18 patients required a red blood cell transfusion. These infants were among the most anaemic at entry into the study and 2 of them were unable to complete rHuEPO therapy, while the third developed iron deficiency anaemia. These data indicate that rHuEPO with appropriate iron supplementation may accelerate the recovery from anaemia of prematurity. Larger scale placebo-controlled studies are now needed to confirm these findings and verify their impact on transfusion requirements of premature infants.

Anemia, Neonatal↗
PubMed1992

Comparison of totally implanted and external catheters in paediatric oncology patients.

From June 1982 until December 1989, 93 permanent central venous catheters [59 external catheters (ECs) and 34 implanted catheters (ICs)] were placed in 69 patients. The median age of these patients at placement was 5.6 years for ECs and 8.8 years for ICs (P less than 0.05). Follow-up evaluation was possible on 86 catheters (58 ECs and 28 ICs). The median time of insertion was 236 days and 316 days for ECs and ICs, respectively (P less than 0.05). The median number of open days was 58 for ECs and 66 for ICs (not significant). 17 catheters (6 ECs and 11 ICs) were transiently obstructed (P less than 0.005). 30 episodes of bacteraemia were documented in 20 patients. The incidence of catheter sepsis and bacteraemia of unknown source was one in 278 and 283 open days for ECs and ICs, respectively (not significant). In this retrospective study, ECs appeared to be as safe as ICs when infection was correlated with use of the catheter, but this finding should be confirmed in a randomised design.

Bacteremia↗
PubMed1990

Diagnostic and therapeutic problems of soft tissue tumors other than rhabdomyosarcoma in infants under 1 year of age: a clinicopathological study of 34 cases treated at the Institut Gustave-Roussy.

Thirty-four cases of soft tissue tumors (STT) other than rhabdomyosarcoma in infants under 1 year of age were seen in our institution between 1955 and 1985. All were diagnosed initially as malignant tumors except for three cases of fibromatosis, and, thus, they received therapy appropriate at that time. During a recent pathologic review, four were seen to have had hemangioma, six hemangiopericytoma, one hamartoma, seven fibromatosis, eight fibrosarcoma, and eight unclassified sarcomas. Of these 34 cases, the initial histological diagnosis was confirmed in only 17. Sixteen patients were believed to have received inappropriately aggressive therapy; indeed, four of these cases diagnosed prior to 1975 had been benign. Major long-term side effects were seen in 7/16 treated patients (six radiotherapy, one surgery), who, in retrospect, should have received less aggressive treatment. The reasons for these initial errors in diagnosis included doubtful histologic features associated in some cases with alarming clinical presentation. We believe that difficulties still remain in distinguishing benign from malignant STT in this age group by histological examination. Therefore, we urge extreme caution in using aggressive therapy before the diagnosis is certain.

Age Factors↗
PubMed1990

Effects of recombinant human erythropoietin in infants with the anemia of prematurity: a pilot study.

In an attempt to stimulate endogenous erythrocyte production and thereby provide an alternative to erythrocyte transfusions, we administered recombinant human erythropoietin (rHuEpo) in doses of 75 to 300 units/kg/wk to seven infants with the anemia of prematurity. Treatment was started between 21 and 33 days of life, maintained for 4 weeks, and was well tolerated. All the patients had low baseline serum erythropoietin levels. After rHuEpo therapy, the number of reticulocytes increased from a mean baseline count of 75 x 10(9)/L to 95, 141, and 165 x 10(9)/L on days 7, 10, and 14 of therapy, respectively. Correction or stabilization of the anemia was observed in six of seven patients, whose estimated total erythrocyte volume increased by 49% during therapy (vs a predicted increment of 18% in the absence of rHuEpo). In one patient, however, the hematocrit declined during the treatment, and in three of the responders a secondary fall in hematocrit was noted either during therapy or after its discontinuation. Serum iron and ferritin levels rapidly decreased after the initiation of rHuEpo therapy, and in most patients transient early thrombocytosis and late neutropenia were observed. These data suggest that rHuEpo may correct or stabilize the anemia of prematurity. Its effects, however, may be limited by a variety of factors, among which iron availability probably plays an important role. Controlled studies will be needed to confirm these preliminary observations.

Anemia↗
PubMed1989

Permeability and penicillin-binding protein alterations in Salmonella muenchen: stepwise resistance acquired during beta-lactam therapy.

A patient with Salmonella muenchen sepsis was unsuccessfully treated with ampicillin. During therapy, four strains that showed stepwise ampicillin resistance and affected other beta-lactams and unrelated antibiotics were isolated sequentially. Resistance was caused by decreased outer membrane permeability associated with diminished expression of porin OmpF. Furthermore, the most resistant isolate overproduced the PBP 3 target molecule.

Anti-Bacterial Agents↗
PubMed1989

Varicella-zoster virus infections after autologous bone marrow transplantation in children.

We report a retrospective analysis of children who underwent autologous bone marrow transplantation (ABMT) and subsequently developed a varicella-zoster virus (VZV) infection. Among 236 patients transplanted between January 1979 and December 1987, 54 (23%) aged 2 to 18.5 years (mean 7.2) developed 60 VZV infections (25%); there were 10 cases of chicken-pox in 10 patients, 43 zoster infections in 41 patients and seven disseminated zoster infections in seven patients. Eighty-seven percent of VZV infections occurred within the first 6 months after bone marrow transplantation, with a mean interval of 89 days. No significant risk factors for the development of zoster infections were identified. The incidence of VZV infections following ABMT was similar to that observed after allogeneic bone marrow transplant but the onset was earlier after ABMT (3 vs 5 months) and there were fewer complications (2 vs 18%). Acyclovir and/or adenine arabinoside were administered to 46 patients. One child who had had chicken-pox died of interstitial pneumonitis due to VZV despite antiviral therapy. No other symptomatic visceral dissemination was observed.

Adolescent↗
PubMed1988

[Super intensive treatment followed by bone marrow autograft in cases of hematologic neoplasms and solid tumors].

Thirty-one patients underwent autologous bone marrow transplantation (ABMT) after intensive radio and/or chemotherapy. On 18 occasions, bone marrows were treated in vitro with either Asta-Z 7557, Asta-Z 7654 or the rat monoclonal antibody Campath-1M and complement. Sixteen patients were transplanted for acute leukemia: 6 patients were in first complete remission (CR), 5 in CR greater than 1 and 5 in relapse. Twelve out of fourteen evaluable patients have relapsed. Two patients transplanted in CR 2 and CR 1 remain in CR after 9.5 and 12 months respectively. Nine patients were transplanted for aggressive lymphoma: four patients were in CR 1, 2 in CR greater than 1, 1 in first relapse and 2 refractory to best available second line chemotherapy. All 3 achieved CR after ABMT. Nine patients are evaluable: 4 relapsed and 5 remain in CR at 5, 6.5, 21, 25 and 39 months, this last patient transplanted in a refractory state, the others in CR 1. Four patients were transplanted for refractory Hodgkin's disease: 3 patients are evaluable. One patient achieved complete remission which lasted 9 months. Two patients were transplanted for relapsed solid tumors and achieved a partial response. In conclusion, the response rate is encouraging for patients transplanted during active and sometimes refractory phases of the diseases (8/13 evaluable patients achieved CR). However, for the whole group of patients, including those transplanted for acute leukemia in CR 1, the relapse rate was high. Durable remissions were achieved for patients with aggressive lymphoma who were transplanted early in the disease.

Acute Disease↗