Jürg Gmür

Reptilase®‐R—A New Reagent in Blood Coagulation

Summary. Reptilase®‐R, a purified thrombin‐like snake‐venom enzyme from Bothrops atrox, has been tested for its usefulness as a substitute for thrombin in two coagulation assay systems. Reptilase was found to be more stable than thrombin and not to be inhibited by heparin and hirudin.

Graft-versus-host disease and survival after ABO-incompatible allogeneic bone marrow transplantation: a single-centre experience.

The effect of ABO‐incompatibility on graft versus host disease (GVHD) and survival was evaluated in 173 consecutive patients receiving allogeneic bone marrow transplantation (BMT). Thirty‐four percent of the patients developed GVHD and univariate analysis suggested a higher incidence of GVHD in minor ABO‐incompatibility than in ABO‐identity (14/30, 47% versus 37/112, 33%; P = 0·02). However, using logistic regression adjusted for potential confounders, the GVHD risk did not differ significantly. During a mean follow‐up time of 59 months, the mortality was 37% and survival was significantly dependent on ABO‐compatibility (P = 0·004). In particular, patients with bidirectional ABO‐incompatibility had an excess mortality rate (RR, 7·6; 95% CI, 2·5–23·2; P = 0·0004). Taken together, these results suggest that ABO‐incompatibility may represent a risk factor in allogeneic BMT.

Functional hyposplenia after allogeneic bone marrow transplantation is detected by epinephrine stimulation test and splenic ultrasonography

Splenic function was evaluated after subcutaneous epinephrine injection (0.5 mg/m2) in 15 bone marrow transplant (BMT) recipients, 10 healthy volunteers and 5 healthy asplenic men. Healthy volunteers and BMT recipients with minor primary induction chemotherapy (mRx) showed similar rise in platelet (plt) and neutrophil granulocyte (PMN) counts and similar contraction of spleen. Patients with intensive primary induction chemotherapy (MRx), however, had significantly smaller spleens and spleen contraction (p < 0.02) and no plt increase (p < 0.05) when compared with healthy volunteers. 2 patients with MRx even exhibited a decrement of plt count after epinephrine, similar to that observed in all 5 healthy asplenic subjects tested. Our results suggest that mRx and conditioning for BMT including total body irradiation (TBI) does not alter the splenic function, but that the combination of MRx and conditioning regimen including TBI may cause functional hyposplenism, sensitively revealed by reduction in plt count after epinephrine stimulation.

Amoxicillin-Induced Immune Hemolysis

Severe hemolysis occurred in a 51-year-old female after a 17-day course of intravenous amoxicillin. A strongly positive direct antiglobulin test (anti-IgG titer 1:2,000) ensued which disappeared after withdrawal of the drug. Both the patients serum and eluate obtained from the patients red cells contained an IgG antibody which reacted with red blood cells coated in vitro with amoxicillin, but not with uncoated cells. In addition, high-titer antipenicillin, antiampicillin and antiamoxicillin IgG antibodies could be demonstrated in her serum by a RAST-based solid-phase radioimmunoassay. The patients hemolysis gradually subsided within 1 week after discontinuing the drug. This is the first report of amoxicillin-induced immune hemolytic anemia.

Transient pure red cell aplasia caused by antilymphoblast globulin after cadaveric renal transplantation.

Transient pure red cell aplasia (PRCA) in three consecutive patients receiving ATG for management of kidney graft rejection prompted a systematic study of the effects on erythropoiesis of the ATG preparation used at our institution. We found that 90% of patients treated with rabbit anti-T lymphoblast globulin developed reticulocytopenia (< 17,000 reticulocytes/mm3), with complete disappearance of reticulocytes in 65% of patients and increased requirement for red cell transfusion. PRCA, with selective aplasia of erythroblasts was confirmed by bone marrow aspiration in 4 patients volunteering for aspiration, and by the kinetic of the disappearance of blood reticulocytes in relation to the beginning of ATG treatment. The nadir of thrombocytes and lymphocytes, blood cells directly destroyed by ATG in circulation, followed the start of ATG treatment within 1 to 4 days. In contrast the nadir of reticulocyte counts occurred later, between day 7 and 13 after ATG was begun, reflecting the fact that toxicity was directed against red cell precursors rather than mature circulating cells. In agreement with these clinical findings ALG was found to be cytotoxic in vitro for erythroid precursors. Analogously to autoimmune PRCA caused by auto-antibodies to erythroblasts, this type of PRCA could be viewed as “heteroimmune disease.”