Biomedical subjects

P Knoebl

Publications and source records attributed to P Knoebl.

4 recordsLinked to original sources

PubMed1999

Post-transplant acute myeloid leukemia (PT-AML).

Acute myeloid leukemia following organ transplantation (PT-AML) is a rare event with only a few published cases in the literature. We present three patients who developed AML (FAB M1, M5, M4) after renal, double lung or liver transplantation. Molecular analysis detected a t(9;11) in one patient and documented the recipient origin of AML in a second patient. All patients were treated with chemotherapy. Immunosuppression was reduced to cyclosporin A (CsA) and prednisone in two patients and to prednisone alone in one patient. Two patients achieved a complete remission (CR), with a remission duration of 4.6 months in one patient, the other patient died from septicemia after 15.2 months in CR. One patient was refractory to chemotherapy and died from septicemia. This report together with the documented cases in the literature suggests that PT-AML (1) develops after a median interval of 5 years after transplantation with variable latency (range, <1-17 years); (2) is heterogeneous with respect to FAB classification; (3) shows chromosomal and molecular changes typical of therapy-related AML (t-AML: -7, +8, 11q23, inv16, t(15;17)); (4) standard chemotherapy is feasible after reduction of immunosuppression and produces a CR rate of 56% with a median remission duration of 4.6 months and an overall survival of 2.6 months; (5) the major complications are early death (25%), gram-negative septicemia, progressive disease or relapse. This review provides diagnostic and therapeutic experiences and guidelines for the management of this increasing group of post-transplant patients.

Acute Disease↗

PubMed1998

Leukemia-free survival and mortality in patients with refractory or relapsed acute leukemia given marrow transplants from sibling and unrelated donors.

Between April 1982 and February 1997 39 patients (24 male, 15 female) with refractory acute leukemia and a median age of 31 years (19-51 years) received allogeneic marrow grafts from an HLA-identical sibling (n = 27), HLA-identical unrelated donor (MUD; n = 10) or 1-antigen mismatched unrelated donor (n = 2). Twenty-eight patients had acute myelogenous leukemia and 11 acute lymphoblastic leukemia. For conditioning most patients received total body irradiation combined with cyclophosphamide (n = 23) or etoposide (n = 7). For graft-versus-host disease prophylaxis patients received cyclosporin A (CsA) and methotrexate (MTX) (n = 20), MTX alone (n = 3), CsA and methylprednisone (n = 6), or CsA alone (n = 10), respectively. As of June 1997 probability of leukemia-free survival projected to 3 years after BMT was 14% for patients given sibling marrow grafts and 28% after MUD transplantation. Transplant-related mortality projected to 3 years was 32% after sibling and 37% after MUD marrow grafting. Although not significantly different, probability of relapse projected to 3 years after BMT was lower after MUD at 56% compared to 78% with sibling BMT. Thus, high-dose chemo/radiotherapy followed by allogeneic marrow infusion has a curative potential for patients with refractory leukemia and offers the chance of long-term disease-free survival for some patients.

Acute Disease↗

PubMed1997

Prostaglandin E1 inhibits platelet decrease after massive blood transfusions during major surgery: influence on coagulation cascade?

BACKGROUND: A plunge in platelet count if often observed after massive blood transfusions during major surgery. This study was designed to assess whether the prophylactic administration of prostaglandin E1 (PGE1) might prevent this drop in platelet count. METHODS: Forty-five patients receiving massive transfusions of packed red blood cells (> 10 units) during major orthopedic surgery were enrolled in a prospective, randomized, double-blind, placebo-controlled study and divided into two groups: group 1 (therapy group) received intravenous PGE1 up to 30 ng/kg/min for 72 hours after surgery, and group 2 (placebo group) received a placebo during the same time period. RESULTS: The patients in group 1 suffered no reduction in platelet count and thus required no platelet concentrate transfusions. In contrast, a significant postoperative drop in platelet count (p < 0.05) was observed in the placebo group between days 3 and 5 after surgery when compared to the therapy group, necessitating transfusions of platelet concentrates in this group. Similarly, red blood cell count and hemoglobin were far more stable in the therapy group, which required fewer transfusions of red blood cells than did the placebo group (p < 0.05). There seemed to be a tendency toward a consumptive coagulation disorder in the placebo group as indicated by a decrease of fibrinogen levels, prothrombin time, and antithrombin III activity, and an increase of partial thromboplastin time. The incidence of adult respiratory distress syndrome was slightly lower in the therapy group. Last but not least, the length of intensive care unit stay was significantly shorter in the therapy group (p < 0.05). CONCLUSION: In our study, the administration of PGE1 prevented a reduction in platelet count. Furthermore, measurements of clotting activity furnished the possibility that PGE1 might inhibit transfusion-induced coagulation disturbances. We recommend that PGE1 should be considered in patients requiring massive transfusion during major surgery.

Adult↗

PubMed1995

Enhanced serum levels of thiobarbituric-acid-reactive substances in diabetes mellitus.

PURPOSE: To investigate whether serum levels of lipid peroxides measured as thiobarbituric-acid-reactive substances (TBARS) differ in type I and type II diabetic patients, whether serum levels correlate with late sequelae of diabetes, and whether serum levels of free vitamin E correlate with levels of lipid peroxidation by-products. PATIENTS AND METHODS: The relationship among lipids, glycosylated hemoglobin A1c (HbA1c), lipid peroxides measured as TBARS, and free vitamin E was determined in 158 patients. Fifteen of the 77 patients with type I diabetes and 39 of the 81 patients with type II diabetes had clinically apparent peripheral vascular disease or coronary artery disease, or both. RESULTS: Compared with control subjects, serum levels of TBARS were found to be significantly elevated (P < 0.001) in diabetic patients, and type II diabetic patients had significantly higher levels (P < 0.001) than type I patients. Both type I and type II diabetic patients with good metabolic control (HbA1c < 6.5%) had significantly lower (P < 0.005) TBARS levels than patients with poor metabolic control, but all groups had higher levels than the control group. Type II patients with angiopathy had significantly higher levels of TBARS than patients without angiopathy. Free vitamin E levels in control subjects and diabetic patients did not differ statistically. CONCLUSION: Serum levels of TBARS were significantly increased in all patients suffering from diabetes mellitus, whereby TBARS levels did not depend on the total amount of circulating lipids. It can be suggested that the enhanced lipidperoxidation is contributed to an increased formation of free radicals in diabetes mellitus.

Adult↗