Drop In Platelet Count Research Articles

Subsequent Vaccination against SARS-CoV-2 after Vaccine-Induced Immune Thrombotic Thrombocytopenia.

Background: Vaccine-induced immune thrombotic thrombocytopenia (VITT) is a rare but severe complication following vaccination with adenovirus vector-based COVID-19 vaccines. Antibodies directed against platelet factor 4 (PF4) are thought to be responsible for platelet activation and subsequent thromboembolic events in these patients. Since a single vaccination does not lead to sufficient immunization, subsequent vaccinations against COVID-19 have been recommended. However, concerns exist regarding the possible development of a new thromboembolic episode after subsequent vaccinations in VITT patients. Methods: We prospectively analyzed follow-up data from four VITT patients (three women and one man; median age, 44 years [range, 22 to 62 years]) who subsequently received additional COVID-19 vaccines. Platelet counts, anti-PF4/heparin antibody level measurements, and a functional platelet activation assay were performed at each follow-up visit. Additionally, we conducted a literature review and summarized similar reports on the outcome of subsequent vaccinations in patients with VITT. Results: The patients had developed thrombocytopenia and thrombosis 4 to 17 days after the first vaccination with ChAdOx1 nCoV-19. The optical densities (ODs) of anti-PF4/heparin antibodies decreased with time, and three out of four patients tested negative within 4 months. One patient remained positive even after 10 months post first vaccination. All four patients received an mRNA-based vaccine as a second vaccination against SARS-CoV-2. No significant drop in platelet count or new thromboembolic complications were observed during follow-up. We identified seven publications reporting subsequent COVID-19 vaccination in VITT patients. None of the patients developed thrombocytopenia or thrombosis after the subsequent vaccination. Conclusion: Subsequent vaccination with an mRNA vaccine appears to be safe in VITT patients.

Assessment of pharmacological effects of methanolic extract of Perovskia abrotanoides as anti-asthmatic and hepato-protectant

Natural compounds derived from plants have been extensively employed in conventional treatments and are a key component of medicinal products. Perovskia abrotanoides, a plant native to Pakistan, is historically used to cure several ailments, while little is known regarding its pharmacological properties. This study aimed to investigate the pharmacological characteristics of the crude methanolic extract of Perovskia abrotanoides. Phytochemical analysis indicated many phytoconstituents capable of profound antioxidant activity, which may play an important role as anti-asthmatic and hepato-protectant. Its anti-asthmatic and hepatoprotective properties were evaluated using models of histamine-induced asthma and liver damage brought on by carbon tetrachloride, respectively. Research was also conducted on the extract's phytotoxic, antibacterial, and anticancer effects. The results demonstrated strong hepatoprotective and anti-asthmatic effects; while no harm other than a drop in platelet count was noted. Also, the extract showed significant antimicrobial activities against Staphylococcus aureus. However, no apoptotic or anticancer potential was found.

Coagulation, fibrinolysis and platelet drop in patients undergoing transfemoral transcatheter aortic valve implantation.

Transcatheter aortic valve implantation (TAVI) leads to transient platelet activation and hypercoagulation status, resulting in thrombocytopenia. This study investigated the associations of coagulation/fibrinolysis status after transfemoral TAVI with valve type, post-TAVI thrombocytopenia, and complication of TAVI. Thrombin-antithrombin complex (TAT) and fibrin/fibrinogen degradation product (FDP) levels were measured before and 1 h, 1 day, and 2 days after TAVI. A percentage drop in platelet count (DPC) was determined from the pre- and lowest post-procedural values. SAPIEN 3 (S3) was implanted in 158 patients and Evolut PRO/PRO+ (Evolut) in 117. Both TAT and FDP increased after TAVI. Pre-TAVI balloon dilatation was generally performed on patients undergoing implantation with Evolut. Peak TAT was then stratified into 4 quartiles (Q1 to Q4). Of all 275 study patients, 69 patients reached ultra-hypercoagulation status (Q4). S3, TAVI without pre-balloon dilatation, DPC and bleeding complications were significantly associated with the ultra-hypercoagulation status after TAVI. TAT was significantly greater 1 h after S3 implantation than Evolut (median [IQR], 43.1 [34.1-59.6] vs. 31.0 [25.0-40.4] ng/mL; p < 0.001). In contrast, FDP levels did not differ between the two at any measurement point. The difference in DPC among the peak TAT quartiles was statistically significant (p < 0.001). The occurrence of bleeding complications was significantly higher in the group with ultra-hypercoagulation status (5.8% vs. 1.0%, p = 0.036). The increase in coagulation status and post-TAVI thrombocytopenia were significantly greater after S3 implantation. Ultra-hypercoagulation after TAVI was related to bleeding complications.

Donor-derived dengue infections - A review of screening protocol and outcomes in an endemic country.

Donor-derived dengue infections present significant challenges to organ transplantation, particularly in endemic regions like Singapore. Although primarily transmitted by Aedes mosquitoes, dengue can also be transmitted through organ transplantation, occasionally with fatal outcomes. This study aims to evaluate the outcomes and evolution of dengue screening protocols for potential deceased donors in Singapore from 2006 to 2022. Initially, screening was done via dengue immunoglobulin M (IgM), targeting donors with specific clinical criteria (thrombocytopenia, drop in platelet count, prolonged prothrombin time/partial thromboplastin time, and discretion of the transplant team), later transitioning to blood dengue reverse transcription-polymerase chain reaction (RT-PCR) in 2007 with similar criteria, and subsequently universal screening in 2016. In 2021, urine dengue RT-PCR was added following a case of donor-derived dengue infection from an aviremic but viruric donor. Out of 431 potential deceased donors, 395 (91.6%) underwent dengue screening, with six (1.5%) testing positive for dengue. In 2006, three positive screens were identified: two through dengue IgM and one via blood dengue RT-PCR; subsequent years saw one positive screen each in 2007, 2008, and 2019 via blood dengue RT-PCR. Potential deceased donors with a positive blood dengue screen were rejected as solid organ and tissue donors. Those with negative blood dengue RT-PCR but positive urine dengue RT-PCR would be rejected as kidney donors, but the use of other organs and tissues was at the discretion of the transplantation team. The optimal screening protocol remains uncertain, but our findings suggest that a universal screening strategy utilizing both blood and urine dengue RT-PCR could be considered in dengue-endemic countries.

The Role of Platelets and Aneurysm Thrombus in the EVAR Post Implantation Syndrome

ObjectivePost implantation syndrome (PIS) is a well-defined entity with unclear etiology, complicating a number of patients with AAAs treated with EVAR. The aim of this study was to assess the platelets’ role and the influence of aneurysmal sac thrombus volumes in the development of PIS. DesignA retrospective analysis of prospectively collected data was performed and 76 patients that were treated by EVAR (2011-2013) were studied. Aneurysms with endoleak were not included in the study. Based on the criteria for SIRS (Systemic Inflammatory Response Syndrome), 17 patients (22%) developed PIS (which is considered a SIRS analogue), while 59 (78%) did not. MethodsThe two groups were compared in relation to the following parameters: baseline platelet count (PLT), decrease of platelet count (PLT drop), volume of the arterial flow before the procedure (V Flow), volume of thrombus of the aneurysm (V thromb), ratio of thrombus volume to aneurysm sac volume (V ratio) and the volume of new formed thrombus (V new). Volume flow measurements were calculated by Osirix ™ software preoperatively and in the 1st month postoperatively. Parametric and non-parametric techniques (unpaired t-test, Mann-Whitney U test) were used accordingly. ResultsBaseline platelets absolute count was greater in the PIS group (239000 ± 17000) vs. the non-PIS group (194000 ± 6900, p=0.004), and the PLT drop was larger in the PIS group (74000 ± 15600 vs. 45000 ± 5300, p=0.019). No difference was found regarding the aneurysm volumes (Vflow, Vthromb, Vratio, Vnew) between the two groups. ConclusionPlatelets, in terms of their absolute baseline count and their decrease after the procedure, seem to be an important factor in developing PIS after EVAR. Further, more tailored studies are needed to elucidate the role of platelets and flow/thrombus volumes in the development of PIS.

CLINICAL AND LABORATORY PROFILE OF ADMITTED PATIENTS PRESENTING WITH FEBRILE ILLNESS DUE TO DENGUE AND SCRUB TYPHUS COINFECTION FROM A TERTIARY CARE HOSPITAL IN SOUTH RAJASTHAN, INDIA

Objective: The present study aims at describing the clinical features, laboratory diagnosis, and complications in patients presenting with febrile illness due to scrub typhus and dengue coinfection from Southern Rajasthan, India. Method: This present prospective, observational, and hospital-based study conducted in the Department of Microbiology of AIMS &amp; RC, Rajsamand, located in Southern Rajasthan, from January 2021 to December 2021. Scrub typhus was diagnosed in the microbiology laboratory by performing SD Bioline, one-step scrub typhus for the detection of IgM antibody, and dengue fever using J.mitra and Co. Pvt. Ltd., rapid card test for the detection of NS1 antigen and IgM antibody. Result: Out of 500 patients suspected of AUFI, 25 (5%) patients diagnosed of having dengue and scrub typhus coinfection. Fever was present in all 25 (100%) patients and 13 (52%) of patients had arthralgia, nausea, and vomiting. The most common sign noticed in our study was pallor and icterus in 10 (40%) patients each followed by shock/hypotension in 8 (32%) and hepatosplenomegaly in 5 (20%). The most predominant laboratory finding was thrombocytopenia (&lt;1.0 × 106/cumm) in 23 (92%) patients, while elevated bilirubin (&gt;2 mg/dl) in 22 (88%) and elevated transaminase and prolonged aPTT in 21 (84%) patients each. The majority of patients 23 (92%) had hepatic dysfunction, i.e., in followed by multi-organ dysfunction (MODS) in 15 (60%). Conclusion: In developing countries like India, particularly in tropical areas, dengue, and scrub typhus coinfection is under-recognized entity. Additional investigation should be carried out in cases of AUFI patients with features such as hypotension, leukocytosis, early drop in platelet counts, and hypoalbuminemia.

Linezolid-Associated Thrombocytopenia: Assessment of Risk Factors in Patients without Hemato-Oncologic Diseases.

Background: Linezolid is used for Gram-positive bacterial infections. Thrombocytopenia is one of its main adverse effects resulting from myelosuppression. Several studies have assessed risk factors that may increase the risk of this adverse effect. However, most studies included patients with hemato-oncologic diseases, which may confound such assessments. This study aimed to investigate risk factors for linezolid-associated thrombocytopenia in patients without hemato-oncologic diseases. Methods: This was a multicenter retrospective case-control study of adult patients treated with linezolid twice daily for ≥3 days. Patients with hemato-oncologic diseases, active dengue fever, active COVID-19, baseline platelet count <100 × 103/mm3, concurrent therapy with trimethoprim/sulfamethoxazole or valproic acid, and a recent platelet transfusion within 7 days were excluded. Thrombocytopenia was defined as a drop in platelet count below 100 × 103/mm3. Results: Out of 158 evaluated patients, 33 developed thrombocytopenia, indicating an incidence rate of 20.9%. Of all the risk factors assessed, creatinine clearance of <60 mL/min and bacteremia/infective endocarditis were significantly associated with linezolid-associated thrombocytopenia (adjusted odds ratios, 3.25 and 5.95; 95% CI 1.12-9.45 and 1.23-28.66; p = 0.031 and 0.026, respectively). End of therapy platelet counts were significantly lower in the cases than in the controls (79 vs. 243 × 103/mm3; p < 0.001). Similarly, the percentage of platelet count change was significantly different (-55.1% vs. -10.2%; p < 0.001). Conclusions: In our study, the incidence rate of linezolid-associated thrombocytopenia was 20.9%, and we found that patients with renal impairment and bacteremia may need close monitoring of platelet counts. Prospective studies are warranted to evaluate the potential need for renal dose adjustment.

Multi-center study on mortality in children, and adults with sickle cell anemia-risk factors and causes of death

Sickle cell disease (SCD) is a major public health burden worldwide with increasing morbidity and mortality. The study evaluates the risk factors associated with mortality in SCD patients, between the years 2006 and 2020 at three hospitals in Oman. The analysis includes clinical manifestations, haematological, biochemical, and radiological parameters, use of antibiotics, and blood and exchange transfusions. Our cohort included 123 patients (82 males, 41 females), with a median age of 27 (Interquartile Range 21–35 years). SCD related complications included acute chest syndrome (ACS) in 52.8%, splenic sequestration in 21.1%, right upper quadrant syndrome in 19.5%, more than > 6 VOC/year in 17.9%, and stroke in 13.8%. At the terminal admission, patients had cough, reduced O2 saturation, crepitation and fever in 24.4%, 49.6%, 53.6% and 68.3% respectively. Abnormal chest X-ray and chest CT scan were seen in 57.7%, and 76.4% respectively. Laboratory parameters showed a significant drop in hemoglobin (Hb) and platelet counts from baseline, with a significant rise in WBC, LDH and CRP from baseline (p < 0.05, Wilcoxon Signed Ranks test). All patients received antibiotics, whereas, 95.9% and 93.5% received simple blood transfusions, and exchange transfusions respectively, and 66.6% required non-invasive ventilation. Among the causes of death, ACS is seen in 32 (26%), sepsis in 49 (40%), and miscellaneous in 42 (34%). Sudden death was seen in 32 (26%) of patients. Male gender, with low HbF, rapid drop in Hb and platelet, and increased in WBC, LDH, ferritin, and CRP, correlated significantly with mortality in this cohort.

Lijekovima uzrokovana imuna trombocitopenija – prikaz bolesnice

Thrombocytopenia is defined as a reduced platelet count. Drug-induced immune thrombocytopenia (DITP) is a condition mediated by antibodies developed following the ingestion of a certain medication. A sudden drop in platelet count accompanied by ecchymosis, petechiae, and mucosal bleeding following the introduction of a new medication should raise suspicion for DITP. This case report describes the case of a 76-year-old female patient who first appeared at the Emergency Department (ED) with symptoms related to heart failure and atrial fibrillation. The patient was taking warfarin as an anticoagulant therapy when she presented herself to the ED. Following a short hospitalization at the Cardiology Department, the patient was discharged home with dabigatran instead of warfarin as the anticoagulant therapy. After several days of taking dabigatran, the patient came to the ED with a chief complaint of dark-colored urine. Her platelet count (measured using a machine and manually counted) was 13×109/L, and the urinalysis was positive for microhematuria. Dabigatran was excluded from the patient’s medication list. At a later date, following the patient’s request, she started with rivaroxaban prescribed by her general practitioner. The test for anti-platelet IgG antibodies (performed while the patient was taking dabigatran and later rivaroxaban) was positive. Therefore, rivaroxaban was also excluded from the patient’s medication list. After the platelet count normalized, warfarin was reinstituted into the patient's therapy. Due to the diagnosis of DITP being most often empirical, clinicians should suspect DITP if there is a sudden drop in the platelet count accompanied by signs of bleeding following the introduction of a new medication in the patient’s therapy. Additional laboratory workup for transfusion reactions should be conducted, while the culprit medication should be excluded from the patient’s medication list without delay.

Silver Nanoparticles in Biomedical Applications: Insights from In Vitro and In Vivo Studies

This work provides a thorough examination of the biological impacts of silver nanoparticles (AgNPs) via in vitro and in vivo investigations. In vitro tests demonstrated a concentration- dependent reduction in cell viability, decreasing from 90% at 5 µg/mL to 50% at 25 µg/mL, with a substantial rise in reactive oxygen species (ROS) from 20% to 80%. The data indicate that AgNPs may possess cytotoxic effects. Moreover, apoptosis rates escalated from 5% to 18% with increasing doses of AgNP. In vivo investigations revealed significant alterations in hematological parameters, including a decrease in hemoglobin concentrations (from 15 g/dL to 11 g/dL), an elevation in white blood cell counts (from 8 x10³/µL to 12 x10³/µL), and a drop in platelet counts (from 250 x10³/µL to 200 x10³/µL) corresponding to escalating AgNP dosages. Histological studies demonstrated dose-dependent changes in organ tissues, especially the liver, with scores escalating from two to six. Tumor size reductions of 20%, 40%, and 60% were seen with low, medium, and high dosages of AgNPs, respectively. These results underscore the promise of AgNPs for biological applications, especially in tumor therapy. Nonetheless, comprehensive safety evaluations and accurate dosage optimization are required prior to their clinical use. This work highlights the potential biological uses of AgNPs while stressing the need of meticulous evaluation to guarantee their safe and effective incorporation into medical procedures.

Cost-Effectiveness of Caplacizumab in the Warranty Program in Immune Thrombotic Thrombocytopenic Purpura in the USA

Background Immune thrombotic thrombocytopenic purpura (iTTP) is a rare, life-threatening thrombotic microangiopathy. Caplacizumab is a humanized nanobody that inhibits formation of microthrombi in iTTP by disrupting binding of von Willebrand factor to platelets. It is the only treatment approved in combination with plasma exchange therapy (PEX) and immunosuppression (IS) for the treatment of iTTP. The United Kingdom National Institute for Health and Care Excellence (NICE) committee reviewed cost-effectiveness of caplacizumab. The committee concluded that addition of caplacizumab to PEX+IS is cost-effective and recommended that the drug be reimbursed in the UK. The Sanofi Promise Warranty Program ® (SPWP) was introduced in January 2023 in the US. It refunds the full cost of caplacizumab to the hospital when treatment is discontinued due to non-response defined as refractoriness (patient with platelet counts &amp;lt;50 × 10 9/L after 4 days of combined treatment with caplacizumab and PEX+IS; up to 6 doses are refunded), or exacerbation (new drop in platelet count after initial platelet count normalization [&amp;gt;150 × 10 9/L], necessitating re-initiation of PEX after ruling out any causes for the drop in platelet count other than iTTP pathophysiology, up to 12 pre-exacerbation doses are refunded). Objectives To evaluate the cost-effectiveness of adding caplacizumab to PEX+IS from a US perspective within the context of SPWP. Methods The NICE model was adapted to the US setting by replacing UK costs with US costs and discount rates. All clinical assumptions and structure remain unchanged. Clinical inputs were derived from the HERCULES trial (NCT02553317) intent-to-treat population (mean age: 46 years; females: 69%, exacerbation rates: 4.17% during double blind phase and 12.50% in total; refractoriness: 0%). The model consisted of a 3-month decision tree, which captured patient treatment and outcomes over the acute iTTP episode, followed by a long-term Markov model (time horizon: up to 55 years; 3-monthly cycles; Figure 1). An annual discount rate of 3% was applied for both costs and quality-adjusted life-years (QALYs). Under the SPWP, the cost of caplacizumab was assumed to be $0 for refractory patients and those who exacerbate early, no discount was applied for patients who experience exacerbations after drug discontinuation, however, clinical outcomes were captured. Results Prior to the SPWP, caplacizumab addition to PEX+IS delivered a gain of 1.75 QALYs (2.96 life-years [LYs]) as compared with PEX+IS alone, at an increased lifetime cost of $256,000. The incremental cost effectiveness ratio (ICER) was $146,350 per QALY and $86,420 per LY gained ( Table 1). An estimated 4.17% of treated patients qualified for the SPWP. With this outcomes-based program, the ICER improved to $138,480 per QALY and $81,780 per LY gained, respectively ( Table 1). Conclusion Based on these analyses using the UK NICE model adapted with US costs, caplacizumab is cost-effective considering WTP threshold of $150,000 to $200,000 and has improved cost-effectiveness when the warranty program is taken into account. Outcomes based programs can improve the cost effectiveness of a treatment in addition to mitigating concerns of perceived uncertainty of efficacy in treating patients with iTTP in the US.

384. Factors Potentiating the Risk of Linezolid-induced Thrombocytopenia in Patients without Haemato-oncologic Diseases: A Case-control Study

Abstract Background Thrombocytopenia is a major adverse effect of linezolid due to myelosuppression. Many studies assessed factors associated with this effect, but most included patients with haemato-oncologic diseases, which may confound the assessment of thrombocytopenia. Therefore, this study aimed to investigate risk factors for linezolid-induced thrombocytopenia in patients without haemato-oncologic diseases. Methods This was a multicenter retrospective case-control study of adults treated with linezolid 600 mg twice daily for ≥ 3 days. Cases were the patients who developed thrombocytopenia while controls are those who didn't develop it. Exclusion criteria were haemato-oncologic diseases, active COVID-19, active dengue fever, baseline platelet count &amp;lt; 100 × 103/mm3, concurrent therapy with trimethoprim/sulfamethoxazole or valproic acid, platelet transfusion within 7 days before linezolid therapy, and insufficient platelets data. Various factors were assessed for potential association with linezolid-induced thrombocytopenia (defined as drop in platelet count below 100 × 103/mm3). Results 142 patients were included, 31 cases and 111 controls. Patients in both groups had a median age of 62 years and received linezolid for a median of 8 days. Platelet counts significantly dropped in the cases (Figure 1). Figure 2 shows the trend of change in platelet count (the white square indicates the median duration to thrombocytopenia, 8 days). In the univariate analysis, serum creatinine, creatinine clearance, baseline hemoglobin, baseline platelet count, and bacteremia were significantly associated with thrombocytopenia. However, after adjusting for confounders in the multivariate analysis, only low baseline hemoglobin and bacteremia were associated with thrombocytopenia (adjOR = 0.71; 95% CI 0.53-0.95; P = 0.022 and adjOR = 17.02; 95% CI 1.15-251-71; P = 0.039, respectively). Among the cases, those who had a baseline platelet count of &amp;lt; 200 × 103/mm3 developed thrombocytopenia faster as early as 3 days (log-rank P = 0.002; figure 3). Figure 1 Rate of change in platelet count between the cases (thrombocytopenia) and controls (no thrombocytopenia) Figure 2 Trend of platelet counts over 14 days in the cases (thrombocytopenia) and controls (no thrombocytopenia) Figure 3 Kaplan-Meier curve for the development of thrombocytopenia depending on baseline platelet count Conclusion Patients without haemato-oncologic diseases are at risk of linezolid-induced thrombocytopenia. especially those with bacteremia and low hemoglobin level. Patients with low baseline platelet count should be monitored closely early in therapy. Disclosures All Authors: No reported disclosures

Adverse Drug Effect Profiles of Gp2b/3a Inhibitors: A Comparative Review of the Last Two Decades.

ST-Elevation Myocardial Infarction and non-ST Elevation Myocardial Infarction belong to the acute coronary syndrome group of diseases. These conditions are characterized by the complete or partial blockage of one or several coronary arteries, resulting in myocardial injury or necrosis. Various medications are used in their treatment, with the most recent addition being Glycoprotein IIb/IIIa inhibitors. They work by hindering the activity of glycoprotein IIb/IIIa receptors, which, in turn, prevents the clumping of platelets. Some of the GpIIb/IIIa inhibitors available in this category include abciximab, tirofiban, eptifibatide, roxifiban, and orbofiban. With this comprehensive literature review, we aimed to explore the potential adverse effects of these medications and compare the three in terms of their side effects profile. We searched through PubMed and Google Scholar and pinpointed 13 articles aligned with our inclusion criteria: six articles utilized eptifibatide, four were related to abciximab, and three used tirofiban. In 85% of the cases, a severe drop in platelet count, reaching as low as 1000/μL, was reported. Additionally, several other side effects were noted: one case documented multiple bruising spots appearing around the patient's body, two cases reported diffuse alveolar hemorrhage, and one case described a cardiac tamponade resulting from hemorrhagic pericarditis. Our study highlights the crucial significance of keeping a watchful eye on and comprehending the potential drawbacks linked to these medications in cardiovascular treatment. The necessity of researching these medications and their side effects is also evident, as this will significantly enhance the quality of treatment provided.

The Impact of Laboratory Sample Request Evaluation and the Use of Probability Testing for HIT By Trained Physician on the Decrease of Unnecessary Tests and Increase the Likelihood of Positivity

Introduction: Heparin-induced thrombocytopenia (HIT) is an extremely serious and potentially fatal condition that can develop in patients taking heparin-based medications, such as unfractionated heparin (UFH) or low-molecular-weight heparin (LMWH). The laboratory tests for diagnosis of HIT is expensive and time consuming. Clinical assessment (4Ts) followed by testing for Heparin/platelet factor 4 antibody in intermediate and high risk patients is the standard algorithm of pretest for (HIT) which can be later confirmed by serotonin releasing assay if available. Materials and methods: We conducted a retrospective analysis of laboratory practice of pretest evaluation of samples submitted for HIT testing in a cohort of patients treated in a tertiary hospital in Saudi Arabia who had a clinical suspicion of HIT. The 4 T score was a pretest requisite to proceed for electronic request for HIT. It had to be performed by the requesting physicians of different medical specialties. The request then been evaluated by hematopathologist before proceeding. The test will be cancelled if: the 4T score calculated by attending physician is &amp;lt; 4 or if platelet count is normal with no evidence of significant drop in the last 4 days from request or the test was performed at least 2 days before the new request. Additional exercise was performed by two physicians in training after train them to standardize the calculation of the 4T scores without re evaluation by the hematopatologist. The sample proceeded for testing if it met the testing criteria of 4T score &amp;gt; 3 and passed the evaluation by the hematopathologist. All tested sample were performed by immunoglobulin G (IgG) antibodies via an ELISA (Asserachrom HPIA-IgG, Stago Diagnostica STA®) and Optic density ( OD) and was evaluated and considered positive if OD &amp;gt;0.39 with sub classification to low positive 0.4-1, moderate 1-2 and strong if &amp;gt;2. Over a period of 2 years, we received 449 samples for patients who were admitted to our hospital, received prophylactic or therapeutic doses of LMWH or UFH, and underwent an HIT test due to clinical suspicion ( &amp;gt; 50% drop in platelet count from baseline, or ≥ 2 consecutive platelet counts &amp;lt; 150,000 per mm 3 and was defined as possible HIT). The 4 T score was calculated in the hospital system by attending physicians referred to as (system 4T score) and recalculated by trained two physicians and referred to (re calculated 4T score). Descriptive statistics, paired samples statistics, correlations, and analysis of variance (ANOVA) were performed. Results: The test was labeled by the laboratory physician ( hematopathologist ) as not indicated and test was not performed in 156 (35%) for various reasons including low 4 T score &amp;lt;3 in 90 (57%), Normal platelet count &amp;gt; 150 at time of test ( and wrong calculated 4T score) in 28 (18%), duplication of test order in 10 (6.4%%), There was clear other cause of thrombocytopenia in 15 (10%), Bad sample quality 5 (3.2%%) and 8 (5%) for other reasons. The samples for HIT test were for 231(51%) males and 220 (49%) females with mean age 56.3 (1-102) years. The mean platelet count at time of request was 82.9 (2-384) per mm 3. Out of the total cohort 422 (95.1%) patients had received UFH and only 22 (4.9%) received LMWH. There is only 69/449 (15.4%) agreement between the two calculations (system and re calculated score) . Out of the tested samples 293, total positive tests 19 (6.5%), were 11 (3.8%) had low positive for HIT test, moderate positive in 6 (2%) and only 2 strongly positive for HIT. The calculated (system 4T score) of &amp;lt; 4 were 142 (32%) samples while the (re calculated 4T score) were 136 (30%) of which 60 ( 38%) of the cancelled tests by hematopathologist, of which 68 (23%) of tested samples were negative and 7 (37%) of positive tests could have been missed based on this calculation. There were 12 out of 19 had moderate and high score by calculation and positive HIT while there were 17 out of 19 had moderate and high score by system calculation. Conclusion: We are reporting improved detection of HIT and confirmed the value of applying the 4 T score for HIT testing with added value of pre test screening to exclude low probability and cancel samples with no clear indication of HIT due to presence of other causes of thrombocytopenia.The retrospective re calculation even with more trained physicians did not add a value compared to pretest evaluation and screening by hematopathologist which had resulted in cancelation or more than third of the requested tests.

Shear Forces Induced Platelet Clearance Is a New Mechanism of Thrombocytopenia.

Thrombocytopenia has been consistently described in patients with extracorporeal membrane oxygenation (ECMO) and associated with poor outcome. However, the prevalence and underlying mechanisms remain largely unknown, and a device-related role of ECMO in thrombocytopenia has been hypothesized. This study aims to investigate the mechanisms underlying thrombocytopenia in ECMO patients. In a prospective cohort of 107 ECMO patients, we investigated platelet count, functions, and glycoprotein shedding. In an ex vivo mock circulatory ECMO loop, we assessed platelet responses and VWF (von Willebrand factor)-GP Ibα (glycoprotein Ibα) interactions at low- and high-flow rates, in the presence or absence of red blood cells. The clearance of human platelets subjected or not to ex vivo perfusion was studied using an in vivo transfusion model in NOD/SCID (nonobese diabetic/severe combined Immunodeficient) mice. In ECMO patients, we observed a time-dependent decrease in platelet count starting 1 hour after device onset, with a mean drop of 7%, 35%, and 41% at 1, 24, and 48 hours post-ECMO initiation (P=0.00013, P<0.0001, and P<0.0001, respectively), regardless of the type of ECMO. This drop in platelet count was associated with a decrease in platelet GP Ibα expression (before: 47.8±9.1 versus 24 hours post-ECMO: 42.3±8.9 mean fluorescence intensity; P=0.002) and an increase in soluble GP Ibα plasma levels (before: 5.6±3.3 versus 24 hours post-ECMO: 10.8±4.1 µg/mL; P<0.0001). GP Ibα shedding was also observed ex vivo and was unaffected by (1) red blood cells, (2) the coagulation potential, (3) an antibody blocking VWF-GP Ibα interaction, (4) an antibody limiting VWF degradation, and (5) supraphysiological VWF plasma concentrations. In contrast, GP Ibα shedding was dependent on rheological conditions, with a 2.8-fold increase at high- versus low-flow rates. Platelets perfused at high-flow rates before being transfused to immunodeficient mice were eliminated faster in vivo with an accelerated clearance of GP Ibα-negative versus GP Ibα-positive platelets. ECMO-associated shear forces induce GP Ibα shedding and thrombocytopenia due to faster clearance of GP Ibα-negative platelets. Inhibiting GP Ibα shedding could represent an approach to reduce thrombocytopenia during ECMO.

Change in Blood Counts after Palliative Radiotherapy for Multiple Myeloma

Radiation therapy (RT) can provide effective palliation and prevent symptomatic local progression of multiple myeloma (MM). However, RT is sometimes avoided due to concerns for secondary impact to bone marrow, potentially decreasing blood cell counts and precluding ability to receive future systemic therapies. We reviewed a series of MM patients who received palliative RT to assess changes in blood counts from pre-RT to post-RT, hypothesizing that blood counts would not significantly decline after treatment with modern RT volumes and techniques. We utilized a prospectively maintained departmental database and included patients who received palliative RT for MM from 2015 to 2020. Lab values immediately pre-RT (within one month of RT start date) and post-RT (within three months of RT completion) including hemoglobin, lymphocytes, neutrophils, and platelets were collected. Statistical differences from pre-RT to post-RT were assessed using t-tests. ANOVA was used to compare change in blood counts between common dose fractionation regimens (30 Gy in 10 Fractions, 20 Gy in 5, and 8 Gy in 1). A total of 334 MM patients receiving 424 courses of RT were included in this analysis. The median age at start of first treatment was 67 (IQR: 60-76) years. One-hundred ninety-five (58%) were male. Median RT dose was 20 (IQR: 8-24.5) Gy delivered over a median 5 (IQR: 1-5) fractions. Between pre-RT and post-RT, there was no significant change in hemoglobin (+0.1 g/dL (IQR: -0.8, +0.5), p = .076), lymphocyte counts (-0.3*10^9 cells/L (IQR: -0.6, 0), p = .435), or neutrophil counts (-0.1*10^9 cells/L (IQR: -1.1, +0.9), p = .310). In contrast, platelet counts significantly decreased from pre-RT (median 165*10^9 cells/L, IQR: 112-210) to post-RT (median 146, IQR: 93-194) by a median of 17.5 *10^9 cells/L (IQR: -52.5, +14.0, p<0.0001). There were no differences in changes in hemoglobin, neutrophils, or platelets between the common dose fractionations. However, there was a significantly greater drop in lymphocytes after 30 Gy in 10 fractions (p = .039, mean lymphocyte count change (in 10^9 cells/L) for 30 Gy in 10: -0.87, 20 Gy in 5: -0.47, and 8 Gy in 1: -0.27). In this large dataset of patients receiving modern palliative RT for MM, hemoglobin, lymphocytes, and neutrophils did not significantly decline from pre-RT to post-RT. In contrast, there was a statistically significant drop in platelet count by a median 17.5*10^9 cells/L from pre-RT to post-RT, which may or may not be clinically significant depending on clinical context. Patients receiving 30 Gy in 10 fractions had greater drops in lymphocytes than those receiving lower doses. Further analyses will be performed to determine clinical, dosimetric, and volumetric predictors of decline in blood counts after radiation.

Effects of extracorporeal circulation with different time on platelet count after cardiac surgery: a retrospective study based on medical records

Our objective was to observe the effects of extracorporeal circulation (ECC) with different time on platelet count in patients undergoing cardiac surgery. A total of 427 patients who underwent elective cardiac surgery under ECC in affiliated hospital of north Sichuan medical college from January 1, 2018 to July 31, 2021 were divided into three groups according to ECC time. We concluded that thrombocytopenia was common after ECC, maximum drop of the platelet counts after ECC was usually seen on the second day after ECC, and platelet counts started to recover on the fifth day after ECC. With the extension of ECC time, the drop in platelet counts is more pronounced, the volume of perioperative blood loss and blood products transfusion are more, and the recovery level and speed of platelet counts is lower.

Evaluation of some immunological parameters for Staphylococcus xylosus infections in patients with Systemic lupus erythematosus

Purpose: Systemic lupus erythematosus (SLE) is a chronic, systemic autoimmune illness that manifests clinically as well as immunologically and in several lab tests abnormalities. Patients with SLE frequently get infections, which account for 30–50% of morbidity and death. The bacterial species Staphylococcus xylosus is a member of the Staphylococcus genus. This study's objective was to assess several immunological indicators of S.xylosus infections in individuals with systemic lupus erythematosus in the Najaf Governorate of Iraq. Subjects and Methods: Blood samples were taken from 60 SLE patients ranging in age from 16 to 56. Each patient has had a sample of 10 milliliters of blood taken. 5 ml were used to measure immunologic parameters, and another 5 ml were used to diagnose S. Xylosus by culturing a sample on blood agar and mannitol salt agar. culture on mannitol salt agar and blood agar. Results: According to the microbiological tests, 26 specimens (or 43.3%) had isolated bacteria, whereas 34 specimens (or 56.7%) had no sign of bacterial growth. Out of the 26 blood samples collected, S.xylosus was detected in 2 samples. normal amounts of ANA and anti ds-DNA despite SLE sufferers. The results of this study showed that serum levels of CD69, IL-21, and IL-35 significantly increased when compared with controls, despite a substantial drop in Hb, WBC, and platelet counts but an elevated ESR. Conclusions: xylosus produces normal autoantibody levels that are utilized to diagnose SLE. An important factor in the pathophysiology of SLE, which causes the disease to develop, is a high concentration of inflammatory cytokines.

Comparison of complement consumption and platelet accumulation between membrane oxygenators coated with a polymer or heparin.

The membrane oxygenator in extracorporeal circulation circuits is coated with acrylate-copolymer (ACP) or immobilized heparin (IHP) to enhance hemocompatibility. To evaluate the relative features of both coatings, we compared blood components circulated in the circuits with ACP-and IHP-coated membranes in vitro using whole human blood. Whole human blood was heparinized and circulated in two experimental circuits with an ACP-coated reservoir, tubes, and an ACP- or IHP-coated membrane. Platelet (PLT) counts and the amount of total protein (TP), complement component 3 (C3), and complement component 4 (C4) were measured at 0, 8, 16, 24, and 32 h in each experiment (n = 5). The PLT count at 0-h circulation was lower in the IHP-coated than in the ACP-coated circuits (p = 0.034); however, no significant difference was observed at other time points. Reduction in TP at 8-h and 16-h circulation and in C3 at 32-h circulation was lesser in the ACP-coated than in the IHP-coated circuits (p = 0.004, 0.034, and 0.027, respectively); reduction in TP and C3 at other time points and C4 at each time point was not significantly different. There were significant interactions between coating type and circulation duration in the PLT, TP, and C3 transitions (p = 0.008, 0.020, and 0.043, respectively). Our findings suggest that ACP-coated membranes can prevent the initial drop in PLT count and C3 consumption over 32 h, whereas IHP-coated membranes could not prevent this drop in extracorporeal circulation. Therefore, ACP-coated membranes are suitable for short- and long-term extracorporeal life support.

Expert Consensus on the Use of Human Serum Albumin in Adult Cardiac Surgery.

Expert Consensus on the Use of Human Serum Albumin in Adult Cardiac Surgery.