Immune-mediated thrombotic thrombocytopenic purpura in a Jehovah's Witness - Effectiveness of incorporating extracorporeal immunoadsorption to caplacizumab, steroids and rituximab.

We report the case of a Jehovah's Witness adolescent patient with immune-mediated thrombotic thrombocytopenic purpura after SARS-Cov2 infection successfully treated without therapeutic plasma exchange (TPE) using caplacizumab, corticosteroids, rituximab, and extracorporeal immunoadsorption (EIA). Further patients for whom TPE is not an option might benefit from this approach.

Cellular and humoral coagulation profiles and occurrence of IVH in VLBW and ELWB infants.

BACKGROUND AND STUDY PURPOSE: Intraventricular hemorrhage (IVH) is a major complication in preterm neonates with significant long-term morbidity and an increased mortality rate. The role of the immature coagulation system in the pathogenesis of IVH in these infants is still under debate. The aim of this study was to provide reference values for coagulation studies within the first 24h of life, and to relate these findings to the incidence of IVH. PATIENTS AND METHODS: In this retrospective study, a total of 250 (male: 123/female: 127; VLBW: 150 and ELBW: 100) infants were included over a 4-year-period. Coagulation studies were performed within the first 24h of life in all infants. Multiple regression analysis was employed to demonstrate a potential association between IVH and a number of known risk and protective factors for IVH (antenatal steroids, birth weight, gender, IUGR, APGAR score at 10minutes, platelet count, INR, PTT, fibrinogen). RESULTS: Mean birth weight was 1047.9±305.6 (range: 320-1490g). Both cellular (platelets, nucleated red blood cells) and plasmatic coagulation parameters (INR, fibrinogen and antithrombin III) were dependent on birth weight. Moreover, INR levels (p<0.05) were significantly increased in neonates with IVH of any grade. Also, INR was positively correlated with the severity of IVH (Spearman's correlation coefficient: 0.193; p=0.003). While overall fibrinogen levels were not associated with IVH, a fibrinogen level<100mg/dL significantly increased the risk for IVH (p<0.01). CONCLUSIONS: Our data provide a robust set of reference values for both cellular and humoral coagulation studies in VLBW and ELBW infants for the first 24h of life. The results of our study indicate that abnormal INR levels and fibrinogen levels<100mg/dL are significantly associated with the occurrence of IVH in this susceptible cohort.

Novel immunogenic antigens increase classification accuracy in meningioma to 93.84%.

There is growing evidence that simultaneous analysis of multiple autoantibody reactions can be utilized for diagnosis of neoplasms. Using a set of 57 meningioma-associated antigens, we recently separated meningioma patients from individuals without known disease with an accuracy of 90.3%. Here, we ask whether a largely increased set of immunogenic antigens can further improve this discrimination. We used an array with 1,827 human recombinant clones and measured reactivity of serum autoantibodies against the clones by a novel automated image analysis procedure. We were able to separate meningioma sera from sera of healthy controls with a specificity of 95.62%, a sensitivity of 91.83% and an accuracy of 93.84%. Of the analyzed clones, 23 in-frame clones were highly informative for the classification of meningioma vs. normal sera as shown by their AUC values. These results demonstrate that the accuracy of a serum-based diagnostic can be readily and considerably improved by screening extended sets of proteins.

Identification of lung cancer with high sensitivity and specificity by blood testing.

BACKGROUND: Lung cancer is a very frequent and lethal tumor with an identifiable risk population. Cytological analysis and chest X-ray failed to reduce mortality, and CT screenings are still controversially discussed. Recent studies provided first evidence for the potential usefulness of autoantigens as markers for lung cancer. METHODS: We used extended panels of arrayed antigens and determined autoantibody signatures of sera from patients with different kinds of lung cancer, different common non-tumor lung pathologies, and controls without any lung disease by a newly developed computer aided image analysis procedure. The resulting signatures were classified using linear kernel Support Vector Machines and 10-fold cross-validation. RESULTS: The novel approach allowed for discriminating lung cancer patients from controls without any lung disease with a specificity of 97.0%, a sensitivity of 97.9%, and an accuracy of 97.6%. The classification of stage IA/IB tumors and controls yielded a specificity of 97.6%, a sensitivity of 75.9%, and an accuracy of 92.9%. The discrimination of lung cancer patients from patients with non-tumor lung pathologies reached an accuracy of 88.5%. CONCLUSION: We were able to separate lung cancer patients from subjects without any lung disease with high accuracy. Furthermore, lung cancer patients could be separated from patients with other non-tumor lung diseases. These results provide clear evidence that blood-based tests open new avenues for the early diagnosis of lung cancer.

Improving seroreactivity-based detection of glioma.

Seroreactivity profiling emerges as valuable technique for minimal invasive cancer detection. Recently, we provided first evidence for the applicability of serum profiling of glioma using a limited number of immunogenic antigens. Here, we screened 57 glioma and 60 healthy sera for autoantibodies against 1827 Escherichia coli expressed clones, including 509 in-frame peptide sequences. By a linear support vector machine approach, we calculated mean specificity, sensitivity, and accuracy of 100 repetitive classifications. We were able to differentiate glioma sera from sera of the healthy controls with a specificity of 90.28%, a sensitivity of 87.31% and an accuracy of 88.84%. We were also able to differentiate World Health Organization grade IV glioma sera from healthy sera with a specificity of 98.45%, a sensitivity of 80.93%, and an accuracy of 92.88%. To rank the antigens according to their information content, we computed the area under the receiver operator characteristic curve value for each clone. Altogether, we found 46 immunogenic clones including 16 in-frame clones that were informative for the classification of glioma sera versus healthy sera. For the separation of glioblastoma versus healthy sera, we found 91 informative clones including 26 in-frame clones. The best-suited in-frame clone for the classification glioma sera versus healthy sera corresponded to the vimentin gene (VIM) that was previously associated with glioma. In the future, autoantibody signatures in glioma not only may prove useful for diagnosis but also offer the prospect for a personalized immune-based therapy.

Novel autoantigens immunogenic in COPD patients.

BACKGROUND: Chronic obstructive pulmonary disease (COPD) is a respiratory inflammatory condition with autoimmune features including IgG autoantibodies. In this study we analyze the complexity of the autoantibody response and reveal the nature of the antigens that are recognized by autoantibodies in COPD patients. METHODS: An array of 1827 gridded immunogenic peptide clones was established and screened with 17 sera of COPD patients and 60 healthy controls. Protein arrays were evaluated both by visual inspection and a recently developed computer aided image analysis technique. By this computer aided image analysis technique we computed the intensity values for each peptide clone and each serum and calculated the area under the receiver operator characteristics curve (AUC) for each clone and the separation COPD sera versus control sera. RESULTS: By visual evaluation we detected 381 peptide clones that reacted with autoantibodies of COPD patients including 17 clones that reacted with more than 60% of the COPD sera and seven clones that reacted with more than 90% of the COPD sera. The comparison of COPD sera and controls by the automated image analysis system identified 212 peptide clones with informative AUC values. By in silico sequence analysis we found an enrichment of sequence motives previously associated with immunogenicity. CONCLUSION: The identification of a rather complex humoral immune response in COPD patients supports the idea of COPD as a disease with strong autoimmune features. The identification of novel immunogenic antigens is a first step towards a better understanding of the autoimmune component of COPD.

Portal venous stasis during liver resection does not affect platelet aggregability.

INTRODUCTION: To reduce intraoperative blood loss in liver resections surgical bleeding control is often performed by a complete inflow obstruction of the liver called Pringle manoeuvre leading to a portal venous stasis. Platelet aggregability may be affected by this circulatory stasis. MATERIALS AND METHODS: A study population of 11 patients (37-67 years old, 7 females and 4 males) with hepatic tumours underwent elective liver resection. Pringle manoeuvre of up to 50 min duration was used in 4 patients. The other 7 patients were operated using selective vascular clamping. Platelets were aggregated before and after liver resection with adenosine diphosphate, collagen and ristocetin (according to Born). RESULTS: Mean maximal amplitudes of platelet aggregation were comparable before and after liver resection. Statistic analysis did not detect a significant difference between the values before and after liver resection as well as between Pringle manoeuvre and selective vascular clamping. CONCLUSION: Induced platelet aggregability is not affected by the method of surgical bleeding control used in liver resection. Platelet aggregability seems to be resistant even to portal venous stasis of up to 50 min during Pringle manoeuvre.

Central venous oxygen saturation does not correlate with the venous oxygen saturation at the surgical site during abdominal surgery.

INTRODUCTION: Measurement of central venous oxygen saturation has become a surrogate parameter for fluid administration, blood transfusions and treatment with catecholamines in (early) goal directed therapy in the treatment of acute septic patients. These strategies are not easily transferred to the postoperative management of abdominal surgery due to the different conditions in surgical patients. MATERIALS AND METHODS: A study population of 15 patients (8 females/7 males) underwent elective major abdominal surgery: 6 gastrectomies, 5 major liver resections and 4 lower anterior rectum resections. Surgery was performed for primary or secondary malignancy. The patients' age was 65.4+/-12.7 (mean+/-standard deviation, range 44-84, median 62) years. Blood samples were taken intraoperatively from indwelling central venous lines as well as from draining veins at the surgical site. Blood gas analyses to determine the oxygen saturations were performed immediately. All patients were operated in standardized general anesthesia including epidural analgesia and in a balanced volume status. RESULTS: Central venous oxygen saturations and oxygen saturations in blood from the draining veins of the surgical site showed a wide range with high intra- and interindividual differences intraoperatively. Overall, at most time points no correlation between the two oxygen saturations could be detected in three operation types. A significant correlation was only observed at one time point during liver resections. CONCLUSION: Our results show a lack of correlation between central venous oxygen saturations and oxygen saturations in the draining veins of the surgical site during major abdominal surgery. Measurement of central venous oxygen saturations does not seem to be a good surrogate for the local oxygen supply in the field of interest in major abdominal surgery even under standardized conditions.

Collection of WBC-reduced single-donor PLT concentrates with a new blood cell separator: results of a multicenter study.

BACKGROUND: A new cell separator (COM.TEC, Fresenius) was recently developed aimed at efficient collection of WBC-reduced single-donor PLT concentrates (SDPs). STUDY DESIGN AND METHODS: Five German centers collected 554 WBC-reduced SDPs with help of the COM.TEC cell separator. Two multicenter cell counting studies were performed at the beginning and at the end of the study to document uniform counting results among the participating centers. RESULTS: A total of 441 (79.6%) PLT collections were included in the study according to the protocol. A total of 342 single-dose and 99 double-dose SDPs were collected. For single-dose SDPs, an average blood volume of 2826 +/- 409 mL was processed in a donation time of 55 +/- 11 minutes. Mean PLT yield of these products was 3.11 x 1011+/- 0.40 x 1011 and the WBC contamination was 0.11 x 106+/- 0.20 x 106. For double-dose SDPs (PLT count, 5.29 +/- 0.93 x 1011), 3943 +/- 639 mL was processed. The average difference between the target and the collected PLT concentration was -2.8 +/- 12.0 percent for single-dose SDPs and -1.8 +/- 9.5 for double-dose SDPs, respectively. The collection efficiency was 53.7 +/- 5.8 percent for single-dose SDPs and 58.2 +/- 6.2 percent for double-dose SDPs. If all results of each sample from the counting study were set to unity (to the mean over all centers), most PLT determinations were very similar to the mean, for example, near or 1 if set to unity. CONCLUSION: The COM.TEC machine makes it possible to obtain WBC-reduced SDPs that comply with current standards.

On the prophylactic and therapeutic use of danaparoid sodium (Orgaran) in patients with heparin-induced thrombocytopenia.

Heparin-induced thrombocytopenia (HIT) is a rare but dangerous complication of heparin prophylaxis or treatment. The present laboratory tests to measure heparin-associated antibodies are not specific. The diagnosis of HIT mainly depends on the decrease in platelet count and on clinical symptoms. To evaluate clinical outcome, bleeding complications and platelet counts were evaluated in 45 patients with HIT type II (HIT II) treated prophylactically (subcutaneous injections) or therapeutically (intravenous infusion) with danaparoid. Group I included 24 patients with HIT II without thromboembolic complications who received danaparoid twice daily subcutaneously (10 IU/kg) for a mean of 16 days. Group II included 21 patients with thromboembolic complications. They were treated with intravenous danaparoid (2.6 IU/kg/h +/- 1.1) for a mean of 17 days. During subcutaneous prophylaxis, mean anti-Xa levels of 0.2 U/mL and during intravenous treatment, mean anti-Xa levels of 0.4 U/mL were reached. No deaths, amputations, or serious bleeding complications occurred, and no new thromboses were observed in both patient groups. Treatment with danaparoid led to a fast normalization of the platelet counts. This normalization occurred earlier and the concentration of platelets was higher in patients treated with intravenous doses. Danaparoid with subsequent vitamin K-antagonist treatment effectively prevents thromboembolic complications in patients with HIT.