[Measures for allogeneic blood conservation in surgery]. / Fremdblutsparende Massnahmen in der operativen Medizin.

The aim of all efforts to reduce the need of allogeneic blood transfusions is to avoid associated risks. There should particularly be a favourable effect according to the rate of transfusion-transmitted virus infections and immunological side-effects. The acceptance of an individually adjusted lowest haematocrit level and the minimisation of intra-operative blood loss by the application of optimal surgical techniques are among the most essential strategies to reduce or even avoid allogeneic blood transfusions. In addition the following interventions are generally accepted: Preoperative autologous blood donation, where appropriate supported by erythropoietin Preoperative haemodilution, where appropriate supported by erythropoietin Intra- and postoperative blood salvage Topical or systemic pharmacologic interventions to accelerate haemostasis Controlled hypotension Efficacy and indication of the different measures always depend on the individual circumstances of the specific patient. Therefore one should develop an individual approach for every case. In this context the most important subjects are an optimal coordination and if required an appropriate combination of the discussed methods. Algorithms which preoperatively allow approximate calculation of expected transfusion need may be a meaningful tool to facilitate blood conservation planning. However, at the same time one must consider that all strategies to reduce allogeneic transfusion needs are also associated with particular risks. Therefore one has to weigh carefully the pros and cons prior to their application, including the possible alternative of allogeneic transfusion in one's decision making process.

Therapy of coagulation factor VIII autoantibodies with long-term extracorporeal protein A adsorption and immunosuppression.

UNLABELLED: Acquired factor VIII (FVIII) inhibitors in non-haemophiliacs may pose serious treatment problems. MATERIALS AND METHODS: For IgG-adsorptions we utilized an automated plasma separation device and a plasma flow monitor. CASE REPORTS: A 63-year old woman showed life-threatening bleeding because of an inhibitor. After stabilization by porcine FVIII three cycles of a modified Malmoe treatment protocol were applied, followed by long-term cyclophosphamide p.o. and weekly IgG-adsorptions. Within twelve months the patient exhibited a complete remission. A 54-year old man presented a comparable history. Because of a good response after the first cycle he was subsequently switched to the long-term therapy. Up to now (> 7 months) FVIII activities and inhibitor titers remained stable (10-20% rsp. < 3 BU/ml). In both cases no FVIII substitution therapy was necessary. CONCLUSIONS: A modified Malmoe protocol combined with long-term cyclophosphamide p.o. and weekly IgG-adsorptions seems to be an efficient, safe and cost-effective regimen for non-haemophiliacs with FVIII inhibitors.

Treatment of severe myasthenia gravis with protein A immunoadsorption and cyclophosphamide.

Myasthenia gravis (MG) is an autoimmune disease of the neuromuscular junction caused by antibodies against the nicotinic acetylcholine receptor (AChR-Ab). We report a 16-year-old girl with severe MG who showed a poor response to plasma exchange and tryptophan-linked polyvinylalcohol gel immunoadsorption. Further improvement of muscle strength and decline of AChR-Ab could be achieved after initiation of protein-A immunoadsorption (PA-IA). Maintenance therapy with PA-IA and intravenous pulses of cyclophosphamide resulted in a stabilisation of the disease, with a complete remission during the follow-up period of six months. We suggest that PA-IA may be valuable and safe in the management of patients with severe MG, and maintenance therapy with PA-IA and cyclophosphamide may prevent serious and potentially life-threatening relapses of the disease.

[Changes in blood rheology and microcirculation after preparatory combined thrombocytapheresis and plasmapheresis]. / Veränderungen der Blutrheologie und Mikrozirkulation nach präparativer kombinierter Thrombozytapherese und Plasmapherese.

INTRODUCTION: Because of anticoagulation, changes in blood composition, and--perhaps--extracorporeal circulation, donor apheresis should cause alterations in hemorheology and hence in the perfusion of the microvasculature. MATERIAL AND METHODS: 19 regular blood donors were included. According to our standard protocol for automated collection of blood components with the MCS 3p cell separator, we harvested 1 unit of platelets and 2 units of plasma in each case. Prior to, 1 h after, and 24 h after donation, the following parameters were measured: total serum protein (tsp), hematocrit (hc), whole blood and plasma viscosity (wbv/pv), red cell aggregability (rca) and blood flow velocity of the nail-fold capillaries (bfv). RESULTS: The following parameters decreased 1 h/24 h after donation: tsp (p < 0.001/p = 0.008), elastic wbv (p = 0.018/p < 0.001), viscous wbv (p = 0.85/p = 0.0031), pv (p < 0.001/p < 0.001), static rca (p < 0.001/p = 0.0073), dynamic rca (p < 0.001/p = 0.017). The hc showed an initial increase (p < 0.001) with a subsequent overshooting decrease after 24 h (p < 0.001). 1 h after donation bfv raised (p = 0.0065). It decreased after 24 h and remained only slightly higher than the initial level (p = 0.27). CONCLUSIONS: Automated combined collection of platelets and plasma gives rise to: i) Improvement of rheological properties of the donor's blood and increased bfv of his nail-fold capillaries within the 1st h after apheresis. ii) 24 h after donation the improved hemorheological properties remain demonstrable, but the bfv of nail-fold capillaries declines and shows a trend toward the starting-point. iii) Taken together, this is possibly reflecting adapted hemodynamic and vasoconstrictor regulation for altered hemorheological conditions.

[Therapeutic thrombocytapheresis--effect on hemorheologic parameters]. / Therapeutische Thrombozytapheresen--Wirkung auf hämorheologische Parameter.

Common features of all myeloproliferative diseases (CMPE) are a markedly increased number of platelets and restrictions in the subjective feeling of the patients, comprising symptoms like nausea, headache, sensory deficits and transient paresis. Meanwhile, it has been shown that platelet pheresis (mTD) does not only reduce platelet counts sufficiently but also results in an impressive relief of the subjective complaints. To test the part that rheological mechanisms play hereby, relevant rheological parameters in the blood of 22 CMPE patients and of 8 healthy platelet donors as controls were analyzed before and after treatment with an AS-104 cell separator. Concerning the viscosity of whole blood und the filterability of erythrocytes, there was seen neither a difference between the patients and the controls, nor before and after mTD. As a result of treatment of patients, the moderately raised plasma viscosity was normalized, whereas the aggregation of erythrocytes was significantly lowered. It is concluded that there is an influence of hemorheological conditions on the patient's subjective feeling. These would originate in neurological dysfunctions caused by CMPE-induced restrictions in cortical microcirculation. The erythrocyte aggregation, lowered by mTD, would cause an improvement of microcirculatory fluidity and would, in consequence, abolish the neurological symptoms.

[Storage-induced rheologic and biochemical changes in erythrocyte concentrates with added solution and possible correlations]. / Lagerungsbedingte rheologische und biochemische Veränderungen von Erythrozytenkonzentraten in additiver Lösung und deren mögliche Zusammenhänge.

Rheological integrity is one of the essentials for red blood cells (rbc) in capillary circulation. The influences of metabolical/biochemical changes of rbc on their rheological properties are well known, but (to our knowledge) until now there are no published studies, which cover both quality aspects of packed rbc (prbc) in additive solutions. According to our standard operating procedures (SOP) we prepared prbc in additive solution (SAG-M) and plasma from 16 regular blood donations. The buffy coat was discharged. Following parameters were measured on day 1, 14 and 28: extracellular pH, ATP and 2,3-DPG content of rbc, prbc-viskosity, -filterability, -aggregability and filter clogging rate. For examination of the filterability a 5% rbc-suspension in phoshate buffered solution was prepared, the remaining tests were performed with rbc-samples adjusted to a hematokrit of 40% with fresh frozen autologous plasma. In correlation with the depletion of ATP a decrease of rbc flexibility and changes of shape (for example spherocytosis) are well known from the literature. Our results confirm the assumed time dependent deterioration of rheological patterns of prbc in SAG-M, reflecting in an increase of rbc-viscosity and filter clogging rate and a decrease of rbc-filterability and -aggregability. We also observed the expected decrease of pH, ATP and 2,3-DPG during storage. The influences of biochemical changes on rheological alterations are discussed. Therefore we recommend on demand rheological examinations in addition to metabolical/biochemical analyses for an extended quality assurance program, for instance for testing new additive solutions or major changes of SOP.

Demonstration of Borrelia burgdorferi DNA in urine samples from healthy humans whose sera contain B. burgdorferi-specific antibodies.

Since the possibility of asymptomatic infection with Borrelia burgdorferi has been suggested by a positive serology found in healthy subjects, we hypothesized that these subjects might excrete borrelial DNA sequences in urine as happens in patients with Lyme borreliosis. We found borrelial sequences by nested PCR in the urine samples from 3 of 13 healthy B. burgdorferi antibody-positive adults but not in urine samples from 79 antibody-negative healthy controls. After therapy with doxycycline, the urine samples were repeatedly negative for B. burgdorferi DNA. We conclude that urinary excretion of borrelial DNA sequences may occur in seropositive healthy subjects during asymptomatic infection. Demonstration of such sequences in urine must be interpreted cautiously and may not necessarily prove a borrelial cause of disease.

Defective nitrovasodilator-stimulated protein phosphorylation and calcium regulation in cGMP-dependent protein kinase-deficient human platelets of chronic myelocytic leukemia.

The presence and functional role of the cyclic nucleotide signal transduction system was investigated in platelets from patients with myeloproliferative disorders. Platelets from certain patients with chronic myelocytic leukemia showed decreased expression of cGMP-dependent protein kinase, and platelets from two such patients were studied in some detail. These platelets had very little if any cGMP-dependent protein kinase but a normal level of cAMP-dependent protein kinase. They also contained a normal level of VASP (vasodilator-stimulated phosphoprotein, a specific substrate of both cAMP- and cGMP-dependent protein kinase), as well as a functionally intact prostaglandin E1-stimulated cAMP-mediated VASP phosphorylation. In contrast, sodium nitroprusside-stimulated VASP phosphorylation was severely impaired in these cGMP-dependent protein kinase-deficient platelets, despite an exaggerated cGMP response to sodium nitroprusside. Furthermore, whereas selective activation of the cGMP-dependent protein kinase by 8-(4-chlorophenylthio)-cGMP strongly inhibited the ADP- or thrombin-evoked calcium mobilization from intracellular stores in normal platelets, this agonist-evoked calcium response was not inhibited by the cGMP analog in cGMP-dependent protein kinase-deficient platelets. The results demonstrate a defect in the nitrovasodilator-/cGMP-regulated signal transduction system in human platelets from some patients with myeloproliferative disorders, and underscore that a cGMP-dependent protein kinase regulatory system, distinct from that of cAMP-dependent protein kinase or other cGMP-dependent effectors is operative in normal human platelets.

Screening of blood donors and recipients for Borrelia burgdorferi antibodies: no evidence of B. burgdorferi infection transmitted by transfusion.

In the study presented here, the prevalence of antibodies against Borrelia burgdorferi, the etiologic agent of Lyme borreliosis, was determined in a group of blood donors from the Würzburg area (Southern Germany). 13 of 472 donors (2.7%) tested were positive by immunoblotting (IB). These 13 donors were examined in more detail by physical examination, anamnesis and determination of inflammation parameters of the blood. All persons were asymptomatic for Lyme borreliosis. One of 5 who remembered a tick bite actually had suffered from an erythema chronicum migrans 5 years ago. Another one had been affected by fever, headaches and pain in the limbs, arthralgia and motoric disorder in both hands 6 months before examination. Analysis of the blood did not provide any evidence of an acute infection. Moreover, each of the 472 serum samples was analyzed by a hemagglutination test (HAT). 26 (5.5%) showed a positive test result. In order to investigate whether a seroconversion of the recipients by transfusion of B. burgdorferi antibody-positive blood had taken place, 9 recipients of blood products originating from the 13 IB-positive donors were serologically reexamined. All samples taken proved to be antibody-negative. Consequently, the transfusion did not produce any seroconversion in the patients thus treated.

[Therapeutic thrombocytapheresis in patients with myeloproliferative diseases with the cell separators Fresenius AS 104 and Cobe Spectra: biocompatibility and safety]. / Therapeutische Thrombozytapheresen an Patienten mit myeloproliferativen Erkrankungen mit den Zellseparatoren Fresenius AS 104 und Cobe Spectra: Biokompatibilität und Sicherheit.

We studied biocompatibility, safety and efficiency of the two cell separators AS 104 (Fresenius) and Spectra (Cobe) during therapeutic thrombocytaphereses. Although some patients have very high platelet levels and coagulation as well as circulatory equilibrium is easily disturbed, no important activation of coagulation or complement was observed. In respect to patient's safety both cell separators performed very well.

[Infections with Borrelia burgdorferi in Würzburg blood donors: antibody prevalence, clinical aspects and pathogen detection in antibody positive donors]. / Infektionen mit Borrelia burgdorferi bei Würzburger Blutspendern: Antikörperprävalenz, Klinik und Erregernachweis bei antikörperpositiven Spendern.

The prevalence of antibodies against Borrelia burgdorferi, the etiologic agent of Lyme borreliosis, was determined in a group of blood donors from the Würzburg area (Southern Germany). 26 of 472 donors (5.5%) tested positive in a hemagglutination test. When performing immunoblots only 13 donors (2.7%) gave rise to B. burgdorferi-specific antibodies. 9 of them were examined in more detail by anamnesis, physical examination, determination of inflammation parameters of the blood and polymerase chain reaction (PCR) analysis of urine. All persons were asymptomatic for Lyme borreliosis. One of 4, who remembered a tick bite, actually had suffered from an erythema migrans 5 years ago. Another one had been affected by fever, headaches and pains in the limbs, arthralgia and motoric disorder in both hands 6 months before examination. Analysis of the blood did not provide any evidence of an acute infection. In the urine of 2 donors we detected B. burgdorferi-specific DNA by PCR. No seroconversion due to blood transfusion could be observed, when 9 recipients of blood products provided by the 13 seropositive donors were serologically reexamined. PCR analysis of urine samples of 5 recipients was also negative.

[Side effects and risk factors of various plasma donation methods]. / Nebenwirkungen und Risiken verschiedener Plasmaspende-Methoden.

Weekly plasma donations of 600 ml were carried out for ten weeks on 20 probands to compare the Plasma Collecting System, Autopheresis C, Plamapur Monitor and the conventional double bag centrifugation. In terms of compatibility for the donor the different systems appear comparable. The PCS tubing set has to be emptied by isotonic saline at the end of the procedure. In the Autopheresis C and Plasmapur Monitor special care should be taken not to mix up isotonic saline and anticoagulant solutions. The protein concentration is higher in the centrifugation systems, but platelet contamination is higher, too.

[Therapeutic cytapheresis]. / Therapeutische Zytapheresen.

In myeloproliferative disorders many complications are caused by circulatory problems due to high leukocyte or platelet numbers and by hyperviscosity. With cytaphereses and mild cytostatics like Azathioprine, these problems are solved quickly and without major side effects. We report about plateletaphereses for polycythemia vera and megacaryocytic myelosis and leukocytaphereses for chronic myelogenous leukemia. In addition, erythrocytaphereses were carried out successfully in a patient with a combination of heterozygous sickle cell anemia and thalassemia minor.