Detection of bacterial contamination in platelet concentrates by a sensitive flow cytometric assay (BactiFlow): a multicentre validation study.

BACKGROUND: Bacterial contamination of platelet concentrates (PCs) still represents an ongoing risk. As a result of septic complications, particularly observed with older PCs, the shelf life of PCs has been reduced in Germany to 4 days. In this study, bacterial screening of PCs by BactiFlow (BF) flow cytometry was introduced in three German blood services to evaluate the robustness and applicability of the assay. Results were used to discuss the potential for the extension of PC shelf life to 5 days. STUDY DESIGN AND METHODS: A total of 1956 PCs were tested on days 4 or 5+ after PC production using the BF, whereas the BacT/Alert culture system served as reference method. RESULTS: Two PCs were confirmed positive by culture only and were identified as Propionibacterium acnes and Staphylococcus species. Two PCs were confirmed positive for Streptococcus mitis by BF and culture. Additionally, two PCs were culture-positive only in one culture bottle (aerobic: S. mitis and anaerobic: S. hominis). Retrospective analysis of bacterial growth kinetics provide the indication that corresponding bacterial titres were most likely below the BF analytical detection limit (<150 CFU mL(-1) ) and had probably no transfusion relevance. All remaining specimens were tested negative. CONCLUSIONS: Testing of PCs by BF was successfully implemented. The BF proved sufficient as a rapid screening method to improve PC safety. This study further provides data supporting the extension of PC shelf life to 5 days after negative BF testing on day 4.

Autologous stem cell therapy in the treatment of limb ischaemia induced chronic tissue ulcers of diabetic foot patients.

BACKGROUND AND AIM: Despite improvements in surgical revascularisation, limitations like anatomical factors or atherosclerosis limit the success of revascularisation in diabetic patients with critical limb ischaemia. Stem cells were shown to improve microcirculation in published studies. The aim of this study was to evaluate safety, feasibility and efficacy of transplantation of bone marrow derived cellular products regarding improvement in microcirculation and lowering of amputation rate. METHODS: Bone marrow mononuclear cells (BMCs) in comparison with expanded bone marrow cells enriched in CD90+ cells ('tissue repair cells', TRCs) were used in the treatment of diabetic ulcers to induce revascularisation. Diabetic foot patients with critical limb ischaemia without option for surgical or interventional revascularisation were eligible. Parameters examined were ABI, TcPO(2) , reactive hyperaemia and angiographic imaging before and after therapy. RESULTS: Of 30 patients included in this trial, 24 were randomised to receive either BMCs or TRCs. The high number of drop-outs in the control group (4 of 6) led to exclusion from evaluation. A total of 22 patients entered treatment; one patient in the TRC group and two in the BMC group did not show wound healing during follow up, one patient in each treatment group died before reaching the end of the study; one after having achieved wound healing (BMC group), the other one without having achieved wound healing (TRC group). Thus, 18 patients showed wound healing after 45 weeks. The total number of applicated cells was 3.8 times lower in the TRC group, but TRC patients received significantly higher amounts of CD90+ cells. Improvement in microvascularisation was detected in some, but not all patients by angiography, TcPO(2) improved significantly compared with baseline in both therapy groups. CONCLUSION: The transplantation of BMCs as well as TRCs proved to be safe and feasible. Improvements of microcirculation and complete wound healing were observed in the transplant groups.

Bacterial screening by flow cytometry offers potential for extension of platelet storage: results of 14 months of active surveillance.

BACKGROUND: Bacterial contamination is currently the major infectious hazard of platelet transfusion in developed countries. It has been demonstrated that a significant transfusion risk remains, in particular with older platelet concentrates (PCs). In 2009, the shelf life of PCs was therefore reduced in Germany to 4 days after the day of production according to Vote 38. The aim of the present study was the application and implementation of a recently developed flow cytometry-based rapid screening method (BactiFlow) for bacterial contamination at the end of PC shelf life as a routine in-process control. STUDY DESIGN AND METHODS: A total of 472 apheresis-derived PCs were tested using the BactiFlow flow cytometric assay to detect and count bacteria based on esterase activity in viable bacterial cells, while the BacT/Alert automated culture system served as the reference method. The automation potential of the flow cytometric assay was analysed by applying the semi-automated BactiFlow ALS system. RESULTS: An algorithm was developed for use in routine blood bank operations to extend the storage period of PCs. Two of the 472 apheresis PCs tested were positive in culture and identified as Propionibacterium species. One PC was positive for Staphylococcus aureus by both methods. All remaining specimens were tested negative by both methods. CONCLUSIONS: Our study demonstrates that routine bacterial testing of PCs was successfully implemented and the established algorithm proved efficient. The BactiFlow flow cytometric assay is the first rapid screening method which is suitable for a routine application combined with a high sensitivity.

Diffusion-weighted magnetic resonance imaging for the detection of ischemic brain lesions in coronary artery bypass graft surgery: relation to extracorporeal circulation and heparinization.

AIM: Cognitive decline is a well recognized complication after on-pump coronary artery bypass graft (CABG) surgery. We investigated whether the design of extracorporeal circulation (ECC) and the extent of perioperative heparinization have an impact on neurological dysfunction. METHODS: Sixty-three CABG surgery patients were randomly perfused with an uncoated ECC-set (group A) or with two different heparin-coated ECC-sets (groups B and C). In groups A and B, systemic heparin was given in doses of 400 IU/kg body weight, whereas group C received 150 IU/kg body weight. ECC sets in group C included a diagonal pump and low priming as opposed to roller pumps in groups A and B. Furthermore, in group C blood contact to surfaces other than endothelium and heparin coated material was eliminated. Brain lesions were detected by diffusion-weighted magnetic resonance imaging (DWI). Neurological complications were assessed clinically until discharge (manifest motoric, sensitive or cognitive disturbance). Biochemical coagulation and inflammation parameters were measured pre-, peri-, and postoperatively. RESULTS: No major neurological events were observed in either group until discharge. DWIs showed 61 new lesions in 19 of 45 patients who terminated all MRI study procedures. Number and volume of the lesions did not differ between groups (P>0.05). Biochemical and inflammatory parameters showed the expected time courses and variations between groups. CONCLUSION: Ischemic brain lesions are frequently observed in CABG surgery patients but are neither associated with clinically relevant neurological complications nor with ECC set-up and intraoperative heparin dosage. DWI may help in the development of new surgical strategies to reduce postoperative brain damage.

Propionibacterium acnes lacks the capability to proliferate in platelet concentrates.

BACKGROUND AND OBJECTIVES: Propionibacterium acnes is considered to be one of the most frequent contaminants of platelet concentrates (PCs) when anaerobic culture-based detection methods are used. But Propionibacteria are often detected too late when blood products have already been transfused. Therefore, its transfusion relevance is still demanding clarification because studies of the outcome of patients transfused with P. acnes-contaminated PCs are still uncommon. In this study, we monitored clinical effects in patients after transfusion of PCs, which were detected too late in sterility testing. Furthermore, we assessed the bacterial proliferation of Propionibacterium species seeded into PCs to clarify their significance for platelet bacteria screening. MATERIALS AND METHODS: In the look-back process, we followed the route of the putative contaminated PC units from storage to transfusion. In the in vitro study, PCs were inoculated with 1-100 colony-forming unit (CFU)/ml of clinical isolates of Propionibacteria (n = 10). Sampling was performed during 10-day aerobic storage at 22 degrees C. The presence of bacteria was assessed by plating culture and automated BacT/Alert culture system. RESULTS: Propionibacterium acnes shows slow or no growth under PC storage conditions. Clinical signs of adverse events after transfusion of potentially contaminated PC units were not reported. CONCLUSION: Propionibacteria do not proliferate under PC storage conditions and therefore may be missed or detected too late when blood products have already been transfused.

Sterility screening of platelet concentrates: questioning the optimal test strategy.

BACKGROUND: Routine bacterial monitoring of apheresis platelet concentrates (APC) and pooled platelet concentrates (PPC) was introduced in two German blood services using culture and real-time reverse transcriptase (RT)-polymerase chain reaction (PCR). The results of testing are reviewed and used to discuss different strategies for detection of bacterial contamination of PCs. STUDY DESIGN AND METHODS: Two thousand three hundred and sixty-two APCs and 1993 PPCs have been tested by real-time RT-PCR and the BacT/Alert automated culturing system using aerobic and anaerobic culture bottles. After standard processing of PCs and storage of 22-24 h at 20-24 degrees C with agitation, samples were taken under aseptic conditions. Reactive culture bottles were confirmed as positive and bacterial isolates were identified by 16S rRNA analysis and biochemical tests. RESULTS: Seventeen of 2362 tested APCs were reactive in culture and one also in RT-PCR. Of these, 13 APCs were identified as initially positive as Staphylococcus warneri (n = 1, positive in aerobic and anaerobic culture), Propionibacterium acnes (n = 12, positive only in anaerobic culture) and four were initially reactive. Two of 1993 PPCs were initially reactive (anaerobic) and two more were confirmed positive (anaerobic) from a repeat culture and identified as P. acnes. All remaining specimens were tested negative. CONCLUSION: Our study demonstrates that the predominant organisms implicated in platelet bacterial contamination are part of the human skin flora. Inoculating blood culture systems and anaerobic cultivation detects these bacteria after approximately 3-7 days when blood products have been transfused. Based on the presented data different screening strategies are discussed.

Spore-forming organisms in platelet concentrates: a challenge in transfusion bacterial safety.

Bacterial detection and pathogen reduction are widely used methods of minimizing the risk of transfusion-transmitted bacterial infection. But, bacterial spores are highly resistant to chemical and physical agents. In this study, we assessed the bacterial proliferation of spore-forming organisms seeded into platelet concentrates (PCs) to demonstrate that spores can enter the vegetative state in PCs during storage. In the in vitro study, PCs were inoculated with 1-10 spores mL(-1)of Bacillus cereus (n = 1), Bacillus subtilis (n = 2) and Clostridium sporogenes (n = 2). Sampling was performed during 6-day aerobic storage at 22 degrees C. The presence of bacteria was assessed by plating culture, automated culture and real-time reverse transcriptase-polymerase chain reaction (RT-PCR). Spores of the C. sporogenes do not enter the vegetative phase under PC storage conditions, whereas B. subtilis and B. cereus showed growth in the PC and could be detected using RT-PCR and automated culture. Depending on the species and inoculums, bacterial spores may enter the vegetative phase during PC storage and can be detected by bacterial detection methods.

Preoperative haemostasis testing does not predict requirement of blood products in cardiac surgery.

OBJECTIVE: Standard haemostasis screening tests are performed to reveal unknown congenital or acquired disturbances of plasma and/or platelet haemostasis. Since their diagnostic efficacy is often low, routinely performed haemostasis testing has been questioned. We investigated whether preoperatively assessed haemostasis testing can be used to predict the requirement of blood products. METHODS: We retrospectively assessed haemostasis parameters including platelet function testing by PFA 100 as well as the numbers of red blood cell (RBC) concentrates, fresh frozen plasmas (FFPs), and platelet concentrates (PCs) that were given peri-operatively and during the first two postoperative days in 2,831 cardiac surgery patients. Logistic regression analyses were used to select those parameters, which could predict blood product requirement. RESULTS: Of our study cohort, 56.5% needed RBCs, 15% FFPs, and 5% PCs. The need for RBCs was associated with significantly altered pre-operative values of most haemostasis parameters. However, by the use of logistic regression analysis fibrinogen was the only haemostasis parameter that was independently associated with the use of RBCs (odds ratio 1.56; 95% CI: 1.27-1.91; P <0.001). The predictive value of other parameters such as age, body weight, haemoglobin, and haematocrit was however much higher in comparison to fibrinogen (odds ratios: 1.92-3.50; P <0.001). It was not possible to develop a score based on haemostasis parameters to accurately identify patients at risk for RBC use. Moreover, we were unable to estimate the need for FFPs and PCs using preoperative haemostasis testing. CONCLUSIONS: Our data demonstrate that preoperatively performed haemostasis testing is not predictive in estimating the need for blood products in cardiac surgery patients.

Heparin-coated extracorporeal circulation in combination with low dose systemic heparinization reduces early postoperative blood loss in cardiac surgery.

AIM: According to a recently performed meta-analysis, heparin-bonded circuits do not reduce blood loss in cardiac surgery patients compared to nonheparin-bonded circuits within the first 24 h postoperatively. We investigated the effects of heparin-coated circuits in combination with a reduced systemic heparin dose on early postoperative blood loss (first 12 h), platelet function, and postoperative complications. METHODS: Patients who underwent their first coronary artery bypass graft surgery were included in a randomized prospective study. Group A (n=149) was perfused with an uncoated extracorporeal circulation (ECC)-set and groups B (n=152) and C (n=149) with heparin-coated ECC-sets. In groups A and B, conventional dose systemic heparin was given, whereas group C received low dose systemic heparin. Blood loss was assessed within the first 12 h postoperatively. Moreover, biochemical parameters of pro-coagulant activity and immunological function were measured. RESULTS: None of the pro-coagulant activity markers and immunological parameters measured differed preoperatively or postoperatively between study groups. However, intraoperative platelet counts and maximal intraoperative concentrations of platelet factor 4, ss-thromboglobulin, and poly-morpho-nuclear (PMN)-elastase were lowest in group C, whereas group C also had the highest concentrations of thrombin-antithrombin complex (P<0.018-0.001). Blood loss within the first 12 h postoperatively was 457 +/- 204 mL in group A, 431 +/- 178 mL in group B, and 382 +/- 188 mL in group C (P<0.01). Complication rates and 30-day mortality did not differ between study groups. CONCLUSION: The combined use of heparin-coated circuits and low dose systemic heparinization is able to reduce early postoperative blood loss without enhancing the risk of complications.

Polymorphisms in the xylosyltransferase genes cause higher serum XT-I activity in patients with pseudoxanthoma elasticum (PXE) and are involved in a severe disease course.

BACKGROUND: Pseudoxanthoma elasticum (PXE) is a heritable connective tissue disorder caused by mutations in the ABCC6 gene. Fragmentation of elastic fibres and deposition of proteoglycans result in a highly variable clinical picture. The altered proteoglycan metabolism suggests that enzymes from this pathway function as genetic co-factors in the severity of PXE. Therefore, we propose the XYLT genes encoding xylosyltransferase I (XT-I) as the chain-initiating enzyme in the biosynthesis of proteoglycans and the highly homologous XT-II as potential candidate genes. METHODS: We screened all XYLT exons in 65 German PXE patients using denaturing high performance liquid chromatography and analysed the influence of the variations on clinical characteristics. RESULTS: We identified 22 variations in the XYLT genes. The missense variation p.A115S (XT-I) is associated with higher serum XT activity (p = 0.005). The amino acid substitution p.T801R (XT-II; c.2402C>G) occurs with significantly higher frequency in patients under 30 years of age at diagnosis (43% v 26%; p = 0.04); all PXE patients with this variation suffer from skin lesions compared to only 75% of the wild type patients (p = 0.002). c.166G>A, c.1569C>T, and c.2402C>G in the XYLT-II gene were found to be more frequent in patients with higher organ involvement (p = 0.04, p = 0.01, and p = 0.02, respectively). CONCLUSIONS: Here we show for the first time that variations in the XYLT-II gene are genetic co-factors in the severity of PXE. Furthermore, the higher XT activity in patients with the exchange p.A115S (XT-I) indicates that this polymorphism is a potential marker for increased remodelling of the extracellular matrix.

Molecular cloning and expression of human UDP-d-Xylose:proteoglycan core protein beta-d-xylosyltransferase and its first isoform XT-II.

Human UDP-d-xylose:proteoglycan core protein beta-d-xylosyltransferase (EC 2.4.2.26, XT-I) initiates the biosynthesis of glycosaminoglycan chains in proteoglycans by transferring xylose from UDP-xylose to specific serine residues of the core protein. Based on the partial amino acid sequence of the purified enzyme from human JAR choriocarcinoma cell culture supernatant we isolated a cDNA encoding XT-I using the degenerate reverse transcriptase-polymerase chain reaction method. This enzyme, which is involved in chondroitin sulfate, heparan sulfate, heparin and dermatan sulfate biosynthesis, belongs to a novel family of glycosyltransferases with no homology to proteins known so far. 5' and 3'-RACE were performed to isolate a novel cDNA fragment of 3726 bp with a single open reading frame encoding at least 827 amino acid residues with a molecular mass of 91 kDa. The human XT-I gene was located on chromosome 16p13.1 using radiation hybrid mapping, and extracts from CHO-K1 cells transfected with the XT-I cDNA in an expression vector exhibited marked XT activity. A new 3608 bp cDNA fragment encoding a protein of 865 amino acid residues was also isolated by PCR using degenerate primers based on the amino acid sequence of human XT-I. The amino acid sequence of this XT-II isoform displayed 55% identity to the human XT-I. The XT-II gene was located on chromosome 17q21.3-17q22, and the exon/intron structure of the 15 kb gene was determined. RT-PCR analyses of XT-I and XT-II mRNA from various tissues confirmed that both XT-I and XT-II transcripts are ubiquitously expressed in the human tissues, although with different levels of transcription. Furthermore, the cDNAs encoding XT-I and XT-II from rat were cloned. The deduced amino acid sequences of rat xylosyltransferases displayed 94% identity to the corresponding human enzyme.

Evidence against heterozygous coagulation factor V 1691 G-->A mutation with resistance to activated protein C being a risk factor for coronary artery disease and myocardial infarction.

The aim of our study was to determine the prevalence of the factor V mutation (position 1691 G-->A) in patients with angiographically diagnosed coronary artery disease and myocardial infarction and, as a control, in blood donors. This mutation has already been proved to be the main genetic risk factor for venous thrombosis. In order to detect this mutation in exon 10 of the factor V gene we established a microtiter plate based hybridization assay for the specific detection of wild-type and mutant sequences in factor V gene segments, obtained after amplification by polymerase chain reaction. This test enables us to screen a large number of samples. The mutation was detected in 29 of 317 coronary artery disease (CAD) patients (9.1%) and 18 of 190 blood donors (9.5%) investigated. The mean activated protein C resistance ratios were 3.18 and 3.11, with nearly identical distribution. No increased prevalence of the factor V mutation was found in the CAD group. In 10 of 29 CAD patients (35%) with the factor V 1691 G-->A mutation and in 124 of 288 CAD patients without the mutation (43%) there was a history of myocardial infarction. From our data we conclude that there is no increased risk of developing coronary atheroma or consecutive myocardial infarction resulting from the factor V mutation with protein C resistance.

Serum xylosyltransferase: a new biochemical marker of the sclerotic process in systemic sclerosis.

UDP-D-xylose:proteoglycan core protein beta-D-xylosyltransferase (EC2.4.2.26) is the initial enzyme in the biosynthesis of chondroitin sulfate and dermatan sulfate proteoglycans in fibroblasts and chondrocytes. Secretion of xylosyltransferase into the extracellular space was determined in cultured human dermal fibroblasts. A more than 6-fold accumulation of xylosyltransferase activity in cell culture supernatant was observed (day 1, 0.6 microU per 106 cells; day 9, 4.1 microU per 106 cells); however, intracellular xylosyltransferase activity remained at a constant level (0.4 microU per 106 cells). Exposure of human chondrocytes to colchicine led to a 3-fold decreased level of xylosyltransferase and chondroitin-6-sulfate concentration in cell culture. Specific xylosyltransferase activity and chondroitin-6-sulfate concentration decreased in a concentration-dependent manner and in parallel in culture medium and accumulated 5-fold in cell lysates indicating that xylosyltransferase is secreted simultaneously into the extracellular space with chondroitin sulfate proteoglycans. Xylosyltransferase activities were determined in serum samples of 30 patients with systemic sclerosis. Xylosyltransferase activities in female (mean value 1.28 mU per liter, 90% range 1.10-1.55 mU per liter) and male patients (mean 1.39 mU per liter, 90% range 1.16-1. 57 mU per liter) with systemic sclerosis were significantly increased in comparison with blood donors of a corresponding age. Furthermore, xylosyltransferase activity was correlated with the clinical classification of systemic sclerosis. Female patients with diffuse cutaneous systemic sclerosis showed higher serum xylosyltransferase activities than patients with limited systemic sclerosis. These results confirm that the increase of proteoglycan biosynthesis in sclerotic processes of scleroderma is closely related to an elevated xylosyltransferase activity in blood and demonstrate the validity of xylosyltransferase as an additional diagnostic marker for determination of sclerotic activity in systemic sclerosis.

Viremia and excretion of TT virus in immunosuppressed heart transplant recipients and in immunocompetent individuals.

BACKGROUND: The TT virus (TTV) was discovered in patients with symptomatic posttransfusion hepatitis, but many viremic individuals are asymptomatic. Inadvertent transfusion-associated transmission must therefore be anticipated. We screened blood donors and heart transplant recipients for TTV infections. METHODS: Nested polymerase chain reaction was used to detect TTV DNA in plasma, serum, urine, and fecal samples from 600 blood donors, from 100 healthy individuals, and from 495 heart transplant recipients. RESULTS: A total of 3.2% of the blood donors, but 25% of the heart transplant recipients were viremic. TTV subtypes G1a/b and G2a/b were observed in both groups, but the subtype distributions were discrepant. A severe, acute infection with TTV subtype 3 was observed in one blood donor. The prevalence of TTV infections in heart transplant recipients was not correlated to transfusion frequency. Nine viremic heart transplant recipients and their 75 blood donors were studied in detail. Seven blood donors were viremic, but only two "pairs" of viremic blood donors and transfusion recipients had identical TTV isolates. TTV DNA was detected in the feces of 5% (5/100) of immunocompetent individuals (staff), in 46% (52/112) of viremic heart transplant recipients, and in the urine of 55% (20/36). TTV DNA was detected in six of six batches of pooled "virus-inactivated" plasma (solvent/detergent treated), and in none of eight batches of commercial immunoglobulins. CONCLUSION: Although TTV is transfusion-transmissible, the parenteral transmission rate may have been overestimated. Many TTV infections are apparently acquired by nonparenteral routes. Immunoglobulins are safe but pooled plasma is not safe regarding TTV transmission.

The 536C-->T transition in the human tissue factor pathway inhibitor (TFPI) gene is statistically associated with a higher risk for venous thrombosis.

Tissue factor pathway inhibitor (TFPI) is an important regulator in the extrinsic blood coagulation pathway. Although the regulatory biochemical role of TFPI is evident, the clinical significance of this proteinase inhibitor remains to be elucidated. The definition of a clinical TFPI deficiency seems to be more complex than that of other coagulation inhibitors because the activity and concentration of circulating TFPI can not be considered a true measure of in vivo levels. Its determination in plasma samples by immunological methods or functional assays has been shown to be inadequate in the detection of a clinical deficiency. Therefore, we screened genomic DNA samples of blood donors and thrombotic patients for alterations in the TFPI gene to assess the influence of a modified TFPI in venous thromboembolic diseases. We detected a single nucleotide substitution in exon 7 (536C-->T) leading to a proline to leucine exchange at amino acid position 151 of the protein ([P151L]TFPI) and found the prevalence of heterozygous carriers in German unrelated blood donors to be 0.2% (n = 5120). Four unrelated persons out of 14 probands carrying the genetic variation could be linked to venous thrombosis. For calculation of a potential risk for venous thrombosis for carriers of the mutation we investigated healthy blood donors about thrombotic events. 7 out of 308 blood donors were found to have a history of venous thrombosis, one of them carried the TFPI mutation. Statistical calculation showed a significant relative risk for venous thrombosis for individuals with the trait (odds ratio, 9.3; confidence interval, 1.8-48.6; p <0.01).

Results of heart transplantation in patients with preexisting malignancies.

Twenty patients with end-stage heart failure and preexisting malignancies underwent heart transplantation at a single center, with a neoplasm-free interval before the procedure of 0 to 240 months. Twelve patients were long-term survivors (2 to 72 months); there were 2 early and 6 late deaths, thus justifying heart transplantation in patients with preexisting malignancies in individual cases.

Effects of pulsatile perfusion on plasma catecholamine levels and hemodynamics during and after cardiac operations with cardiopulmonary bypass.

Thirty patients scheduled for elective coronary artery bypass grafting were studied in two groups. Group A had standard cardiopulmonary bypass with nonpulsatile perfusion and group B had pulsatile perfusion. Measurements of plasma epinephrine, norepinephrine, granulocyte elastase, and hemodynamic parameters including mean arterial pressure total peripheral resistance, cardiac index, and pulmonary capillary wedge pressure were made before and after anesthesia induction, after surgical incision, during cardiopulmonary bypass, and 2, 4, and 24 hours after the operation. The venous compliance of the total body venous bed was measured at the end of the operation. In all patients the total net fluid balance was determined during bypass and in the postoperative period. In both groups plasma catecholamine levels increased 5 minutes after institution of bypass (epinephrine 176 +/- 56 to 611 +/- 108 pg/ml and norepinephrine 231 +/- 48 to 518 +/- 100 pg/ml in group A; epinephrine 168 +/- 40 to 444 +/- 100 pg/ml and norepinephrine 162 +/- 44 to 267 +/- 52 pg/ml in group B). The maximum catecholamine level was measured between the end of bypass and 2 hours after the end of bypass (epinephrine 1489 +/- 169 pg/ml and norepinephrine 1542 +/- 108 pg/ml in group A; epinephrine 990 +/- 134 pg/ml and norepinephrine 934 +/- 197 pg/ml in group B). During the same period mean arterial pressure and total peripheral resistance were also significantly higher in group A than in group B mean arterial pressure, 61.4 +/- 3 versus 53.6 +/- 3, p less than 0.06; total peripheral resistance, 1055 +/- 60 versus 899 +/- 45, p less than 0.01). The venous compliance was significantly higher in group A than in group B (2.4 +/- 0.3 versus 1.2 +/- 0.3 ml/mm Hg/kg body weight). The intraoperative and perioperative net fluid balance were significantly higher in group A than in group B (p less than 0.005). The average postoperative tracheal intubation time was also significantly longer in group A than in group B (4.6 +/- 1.2 hours versus 2.7 +/- 0.8 hours, p less than 0.001). No significant difference was detected in either hemoglobin or plasma free hemoglobin content between the two groups postoperatively. The results suggest that pulsatile perfusion, when compared with nonpulsatile perfusion, can attenuate the catecholamine stress response to cardiopulmonary bypass, reduce the fluid overloading of patients, and improve the postoperative recovery period as evaluated by tracheal intubation time.

Tuberculosis in heart transplant recipients.

STUDY OBJECTIVES: To clarify the prevalence and factors associated with tuberculosis, as well as patient survival in heart transplant recipients. DESIGN: A retrospective review of case records of all heart transplant recipients from March 1989 to February 1996 during a 7-year period. SETTING AND PATIENTS: During the period reviewed, 727 orthotopic heart transplantations were performed in 716 patients at the Heart Center Northrhine-Westphalia, Germany. RESULTS: Tuberculosis was proved in seven (1%) patients (four men/three women; age, 33 to 71 years; two miliary lesions, three pulmonary lesions, and two urogenital lesions). None of them had primary history of tuberculosis. Tuberculin skin tests were not performed before transplantation because there were no lesions indicating primary infection of turberculosis. The immunosuppressive regimen was based on double-drug (cyclosporine + azathioprine) therapy. Immunosuppression had been intensified by methylprednisolone pulses at least three times in those seven patients, and prednisone had been used orally in six of seven patients. Tuberculosis developed from 2.5 to 41 months after transplantation. Tuberculosis was found by routine examinations in four of seven patients. Diagnoses were made with both direct microscopy and cultures in six patients, and by histologic study in one. Treatment consisted of isoniazid, rifampicin, ethambutol, and pyrazinamide. Two patients with miliary lesions were treated with four drugs, and the others were treated with three drugs. Isoniazid was used in all patients. Rifampicin, which decreases cyclosporine serum levels, was not used from the beginning in one patient and treatment with it was stopped halfway in another patient because low cyclosporine level had induced rejection. Six of the seven patients are doing well while receiving antituberculous therapy. One patient died with miliary tuberculosis as a cause of death. CONCLUSIONS: The prevalence of tuberculosis in heart transplant recipients was higher than that in the general population. We recommend that a high degree of clinical suspicion is maintained for tuberculosis in heart transplant recipients with meticulous follow-up, and that the treatment of tuberculosis has to be with meticulous care, especially during the use of rifampicin.

The time course of natriuretic hormones as plasma markers of myocardial recovery in heart transplant candidates during ventricular assist device support reveals differences among device types.

BACKGROUND: The natriuretic hormones ANP and BNP are expressed differently in the myocardium. Both hormones have compensatory diuretic activity during heart failure. Mechanical stretch of the myocardial walls induces the expression of these hormones. In failing human myocardium, both ANP and BNP are transcribed in the ventricular myocardium in high amounts. We measured the plasma concentrations of ANP and BNP in patients supported by various ventricular assist devices (VADs) at various times. We analyzed the time courses of ANP and BNP to determine (1) the time scale of their down-regulation as a marker of putative myocardial recovery, (2) their steady-state levels under VAD support and (3) differences caused by various VAD devices. METHODS: We analyzed ANP and BNP using commercially available radioimmune assays. We analyzed the time courses of patients supported by Thoratec (THO) LVAD (n = 8), TCI Heartmate (TCI) (n = 6), Novacor (NOV) (n = 7), and Lionheart (LIO) (n = 3). RESULTS: Patients supported with NOV and some patients with TCI showed down-regulation of BNP to a steady-state level at 30 to 50 days, following a single exponential decay. In contrast, patients supported by THO or LIO did not reveal a determined time course of the natriuretic hormones. Only a few patients reached normal plasma values during VAD support. CONCLUSION: The time courses of ANP and BNP differ among VAD types because of construction and/or driving mode, which might be important when considering patients for weaning from VAD without heart transplant.

Quantification of tissue factor pathway inhibitor in human seminal plasma and in human follicular fluid.

INTRODUCTION: Tissue factor pathway inhibitor (TFPI) is a multivalent Kunitz-type serine proteinase inhibitor, which plays a central role in the extrinsic pathway of blood coagulation. It inhibits activated factor X directly and factor VIIa/tissue factor via a quaternary complex. The composition of human semen is governed by the ejaculatory mixing of sperm-rich epididymal fluid, with secretion provided by the accessory sex glands. It is composed of more than 30 proteins including coagulation and liquefaction proteins. Ovarian follicular fluid plays an important biological role in folliculogenesis and oocyte maturation, and it remains in a hypocoagulable state until ovulation. MATERIALS AND METHODS: TFPI levels were measured in ovarian follicular fluid gained from the punctured follicles of superovulated women (n=70), and, for the first time, in seminal plasma of 28 healthy ejaculate donors and 23 infertile patients with oligozoospermia, asthenozoospermia, or teratozoospermia. RESULTS: TFPI concentrations determined in liquor folliculi (median 298 ng/ml, 90% range 109-648 ng/ml) were four times higher than the levels found in human blood of healthy individuals. TFPI concentrations in seminal plasma samples of infertile men were significantly reduced (median 2.20 ng/ml, 90% range 0.28-6.02 ng/ml, p<0.07) in comparison to healthy donors (median 3.55 ng/ml, 90% range 0.93-7.90 ng/ml). CONCLUSIONS: The high TFPI levels measured in the ovarian follicular fluid underline the physiological importance of this inhibitor for maintaining the hypocoagulable state. The decreased TFPI concentrations in seminal plasma of infertile men support the possible correlation between the coagulation properties of ejaculated semen and male fertility.