Transfusion-transmitted infectious diseases

High Ratio of Human T Cell Lymphotropic Virus Transmission and Prevalence of Human T Cell Lymphotropic Virus Type 1-Associated Diseases in Brazilian Family Groups Followed Up by the GIPH Cohort

A silent spread of human T cell lymphotropic virus type 1 (HTLV-1) has been occurring for thousands of years, with a high prevalence in some regions due to the sexual and vertical transmission and formation of family clusters. The time from HTLV-1 infection until the onset of virus-associated diseases is extremely long, approximately one to three decades. In this study, we evaluated intrafamilial HTLV-1 transmission and associated diseases in 1,204 individuals enrolled and followed up by the GIPH cohort between 1997 and 2017. The family groups (n = 43) were composed of 279 individuals who were tested for HTLV-1/human T cell lymphotropic virus type 2 (HTLV-2) and were classified as two groups according to the index case: blood donor (blood donors referred to the GIPH cohort) and nondonor (individuals referred to the GIPH cohort by other health services). The observed rates of HTLV-1 transmission and associated diseases among the relatives were high. Of 236 family members and sexual partners tested for HTLV, 104 (44.1%) were confirmed as having HTLV infection, with 36.7% of relatives whose index case was blood donors and 56.9% of relatives with nondonor index cases. At least one case of HTLV-1-associated myelopathy was observed in 42.9% of the families with intrafamilial transmission of HTLV-1. Brazil is an endemic area for HTLV-1/2 and has implemented mandatory universal screening of blood donors for HTLV-1/2 since 1993. However, the lack of public health services offer diagnosis for HTLV to the general population and pregnant women in the country makes it difficult to identify infected people, and contributes to the silent spread of the virus.

Transfusion-Transmitted Disorders 2023 with Special Attention to Bone Marrow Transplant Patients

Transfusion medicine is traditionally a strong/fundamental part of clinical practice, saving hundreds of millions of lives. However, blood-borne or transmitted infections are a well-known and feared possibility, a risk we relentlessly mitigate. Pathogens are continuously and rather quickly changing, so during the last decade, many, sometimes exotic, new pathogens and diseases were recorded and analyzed, and some of them were proved to be transmitted with transfusions. Blood or blood component transfusions are carried out after cautious preparative screening and inactivation maneuvers, but in some instances, newly recognized agents might escape from standard screening and inactivation procedures. Here, we try to focus on some of these proven or potentially pathogenic transfusion-transmitted agents, especially in immunocompromised patients or bone marrow transplantation settings. These pathogens are sometimes new challenges for preparative procedures, and there is a need for more recent, occasionally advanced, screening and inactivation methods to recognize and eliminate the threat a new or well-known pathogen can pose. Pathogen transmission is probably even more critical in hemophiliacs or bone marrow transplant recipients, who receive plasma-derived factor preparations or blood component transfusions regularly and in large quantities, sometimes in severely immunosuppressed conditions. Moreover, it may not be emphasized enough that transfusions and plasma-derived product administrations are essential to medical care. Therefore, blood-borne transmission needs continued alertness and efforts to attain optimal benefits with minimized hazards.

Time Trend and Prevalence Analysis of Transfusion Transmitted Infections among Blood Donors: A Retrospective Study from 2001 to 2016

Context

Transfusion-transmitted infections (TTIs) remain a major threat to the patients receiving blood. The incidence of the transmission of various infectious agents has reduced ever since the introduction of various molecular techniques for detection.

Aims

The study tried to figure out accurate estimates of risk and trend of TTI over a period of sixteen years, essential for monitoring the safety of blood supply and evaluating the efficacy of the currently employed screening procedures.

Methods and Material

A total of 57942 blood donors' records were analyzed for the period from January 2001 to December 2016. Chi-square test (χ2) was used to evaluate the relationship between serological positivity and particular donor characteristics. A P value of less than 0.05 was considered statistically significant.

Results

Of the 57942 donations, overall prevalence of TTI was 2.7%. Of these, the reactivity rate of hepatitis B (HBV), hepatitis C, HIV, syphilis, and malaria was 1.8%, 0.42%, 0.2%, 0.31%, and 0.017%, respectively with significant P value (P < 0.05, CI: 95%). Overall prevalence was higher in replacement donors as compared to voluntary blood donors. Trend of TTI prevalence decreased from 2001 to 2016.

Conclusions

This epidemiological research on TTI is important for the region, as estimated disease burden based on comprehensive epidemiological research provides the foundation for public policy to ensure an easily accessible and adequate supply of safe and quality blood and blood components to the needy patients.

West Nile virus IgG antibodies among blood donors in Sudan: a cross-sectional study

while the world is concentrated on fighting SARS-CoV-2, other viruses such as West Nile virus (WNV) attack the communities silently. West Nile Virus (WNV) is established as one of the infectious agents that transmissible blood transfusion. The present study is cross-sectional, conducted in the central blood bank, Khartoum state, Sudan, and aimed to determine WNV IgG antibodies among blood donors.

METHODS

the antibodies of the IgG class against West Nile virus in the serum were determined using the ELISA technique. Ninety blood donors participated in this study.

RESULTS

the results showed that 67(74.4%) of participants had positive IgG for WNV. The majority of positive participants 28/67(41.8%) had an age between 28-37 years followed by an age group 18-27 years 24/67(35.8), the dominant blood group of the positive WNV IgG participants was A+ 26/67 (38.8%) followed by O+ 19/67(28.4%). The result displayed that 40(59.7%) of the positive IgG had donated blood several times and 58 (86.6%) had a blood transfusion. Statistical analysis showed an insignificant association between age group, blood group, blood donation, blood transfusion, and West Nile Virus.

CONCLUSIONS

the high IgG seroprevalence (which indicated previous infection) in the present study suggests high virus circulation in Sudan. This situation proposed that WNF screening test should be part of blood transfusion screening tests in Sudan.

Recent Advances in Plasma-Engineered Polymers for Biomarker-Based Viral Detection and Highly Multiplexed Analysis

Infectious diseases remain a pervasive threat to global and public health, especially in many countries and rural urban areas. The main causes of such severe diseases are the lack of appropriate analytical methods and subsequent treatment strategies due to limited access to centralized and equipped medical centers for detection. Rapid and accurate diagnosis in biomedicine and healthcare is essential for the effective treatment of pathogenic viruses as well as early detection. Plasma-engineered polymers are used worldwide for viral infections in conjunction with molecular detection of biomarkers. Plasma-engineered polymers for biomarker-based viral detection are generally inexpensive and offer great potential. For biomarker-based virus detection, plasma-based polymers appear to be potential biological probes and have been used directly with physiological components to perform highly multiplexed analyses simultaneously. The simultaneous measurement of multiple clinical parameters from the same sample volume is possible using highly multiplexed analysis to detect human viral infections, thereby reducing the time and cost required to collect each data point. This article reviews recent studies on the efficacy of plasma-engineered polymers as a detection method against human pandemic viruses. In this review study, we examine polymer biomarkers, plasma-engineered polymers, highly multiplexed analyses for viral infections, and recent applications of polymer-based biomarkers for virus detection. Finally, we provide an outlook on recent advances in the field of plasma-engineered polymers for biomarker-based virus detection and highly multiplexed analysis.

The Mirasol Evaluation of Reduction in Infections Trial (MERIT): study protocol for a randomized controlled clinical trial

BACKGROUND

Transfusion-transmitted infections (TTIs) are a global health challenge. One new approach to reduce TTIs is the use of pathogen reduction technology (PRT). In vitro, Mirasol PRT reduces the infectious load in whole blood (WB) by at least 99%. However, there are limited in vivo data on the safety and efficacy of Mirasol PRT. The objective of the Mirasol Evaluation of Reduction in Infections Trial (MERIT) is to investigate whether Mirasol PRT of WB can prevent seven targeted TTIs (malaria, bacteria, human immunodeficiency virus, hepatitis B virus, hepatitis C virus, hepatitis E virus, and human herpesvirus 8).

METHODS

MERIT is a randomized, double-blinded, controlled clinical trial. Recruitment started in November 2019 and is expected to end in 2024. Consenting participants who require transfusion as medically indicated at three hospitals in Kampala, Uganda, will be randomized to receive either Mirasol-treated WB (n = 1000) or standard WB (n = 1000). TTI testing will be performed on donor units and recipients (pre-transfusion and day 2, day 7, week 4, and week 10 after transfusion). The primary endpoint is the cumulative incidence of one or more targeted TTIs from the Mirasol-treated WB vs. standard WB in a previously negative recipient for the specific TTI that is also detected in the donor unit. Log-binomial regression models will be used to estimate the relative risk reduction of a TTI by 10 weeks associated with Mirasol PRT. The clinical effectiveness of Mirasol WB compared to standard WB products in recipients will also be evaluated.

DISCUSSION

Screening infrastructure for TTIs in low-resource settings has gaps, even for major TTIs. PRT presents a fast, potentially cost-effective, and easy-to-use technology to improve blood safety. MERIT is the largest clinical trial designed to evaluate the use of Mirasol PRT for WB. In addition, this trial will provide data on TTIs in Uganda.

TRIAL REGISTRATION

Mirasol Evaluation of Reduction in Infections Trial (MERIT) NCT03737669 . Registered on 9 November 2018.

Cognitive screening in HTLV-1-infected people using a self-perceived memory score and auditory P300

The HTLV-1-associated myelopathy/tropical spastic paraparesis (HAM/TSP) is the most common neurological manifestation associated with human T-cell lymphotropic virus type-1 (HTLV-1) infection. Although cognitive impairment has been highlighted in the spectrum of HTLV-1 neurological manifestations, it may go unnoticed in those who do not spontaneously report it. We aimed at evaluating the applicability of a self-perceived memory score (SMS) and the cognitive event-related potential (P300) for early detection of cognitive impairment in HTLV-1-infected people. The SMS was measured by a 0-10 point numeric scale combined with a sad-happy face rating scale. The higher the number, the better was the SMS. The P300 was obtained through an oddball paradigm with a mental counting task. The participants were 15 (21.4%) individuals with HAM/TSP, 20 (28.6%) HTLV-1 asymptomatic carriers, and 35 (50%) seronegative controls. We found that SMS (p < 0.001) and P300 latency (p < 0.001) got progressively worse from the seronegative controls to the asymptomatic carriers and then to the HAM/TSP. The results that indicated cognitive impairment were SMS < 7.2 points and P300 latency > 369.0 ms. The HAM/TSP group showed the highest prevalence of altered P300 (80%) and SMS (87%). Interestingly, the asymptomatic group also presented significantly higher prevalence of altered SMS (60%) and P300 (35%) when compared to controls (< 10%). The frequency of cognitive impairment was 16 times higher in the HTLV-1 asymptomatic group and 69 times higher in the HAM/TSP group when compared to controls. The use of SMS in the medical consultation was a useful and easy-to-apply method to screen HTLV-1-infected subjects for everyday memory complaints.

Effects of Tranexamic Acid on Bleeding in Pediatric Surgeries: A Systematic Review and Meta-Analysis

Background: Major pediatric surgeries can cause severe intraoperative blood loss. This meta-analysis aims to evaluate the efficacy of tranexamic acid (TXA) in pediatric surgeries.

Methods: We searched PubMed, Embase, Web of Science, and Cochrane Library from the conception to March 31, 2021 to identify eligible randomized controlled trials (RCTs) that evaluated the efficacy of TXA in pediatric surgeries. Two reviewers choosed studies, evaluated quality, extracted data, and assessed the risk of bias independently. Mean difference (MD) was calculated as the summary statistic for continuous data. We used a random-effects model to measure mean effects. Data were generated from the corresponding 95% confidence interval (CI) using RevMan 5.3 software. Primary outcomes included intraoperative and postoperative blood loss, red blood cell (RBC) transfusion as well as fresh frozen plasma (FFP) transfusion.

Results: Fifteen studies enrolling 1,332 patients were included in this study. The pooled outcomes demonstrated that TXA was associated with a decreased intraoperative (MD = −1.57 mL/kg, 95% CI, −2.54 to −0.60, P = 0.002) and postoperative (MD = −7.85 mL/kg, 95% CI, −10.52 to −5.19, P < 0.001) blood loss, a decreased intraoperative (MD = −7.08 mL/kg, 95% CI, −8.01 to −6.16, P < 0.001) and postoperative (MD = −5.30 mL/kg, 95% CI, −6.89 to −3.70, P < 0.001) RBC transfusion, as well as a decreased intraoperative (MD = −2.74 mL/kg, 95% CI, −4.54 to −0.94, P = 0.003) and postoperative (MD = −6.09 mL/kg, 95% CI, −8.26 to −3.91, P < 0.001) FFP transfusion in pediatric surgeries. However, no significant difference was noted between two groups in duration of surgery (MD = −12.51 min, 95% CI −36.65 to 11.63, P = 0.31). Outcomes of intraoperative and postoperative blood loss and the duration of surgery in included studies were not pooled due to the high heterogeneity.

Conclusion: This meta-analysis demonstrated that TXA was beneficial for bleeding in pediatric surgeries.

Hyperhaemolytic Syndrome in Sickle Cell Disease: Clearing the Cobwebs

Sickle cell disease (SCD) presents with a dynamic background of haemolysis and deepening anaemia. This increases the demand for transfusion if any additional strain on haemopoiesis is encountered due to any other physiological or pathological causes. Patients with cerebrovascular accidents are placed on chronic blood transfusion; those with acute sequestration and acute chest syndrome are likewise managed with blood transfusion. These patients are prone to develop complications of blood transfusion including alloimmunization and hyperhaemolytic syndrome (HHS). This term is used to describe haemolysis of both transfused and "own" red cells occurring during or post-transfusion in sickle cell patients. Hyperhaemolysis results in worsening post-transfusion haemoglobin due attendant haemolysis of both transfused and autologous red cells. The mechanism underlying this rare and usually fatal complication of SCD has been thought to be secondary to changes in the red cell membrane with associated immunological reactions against exposed cell membrane phospholipids. The predisposition to HHS in sickle cell is also varied and the search for a prediction pattern or value has been evasive. This review discusses the pathogenesis, risk factors and treatment of HHS, elaborating on what is known of this rare condition.

Transfusion-transmitted and community-acquired cytomegalovirus infection in seronegative solid organ transplant recipients receiving seronegative donor organs

Solid organ transplant (SOT) recipients who are cytomegalovirus (CMV) seronegative (R-) and receive seronegative donor (D-) organs have a small but currently unquantified risk of both transfusion-transmitted CMV (TT-CMV) and community-acquired CMV (CA-CMV). We retrospectively studied the incidence and clinical symptoms of TT-CMV (infection <1 year posttransplant) and CA-CMV (infection >1 year posttransplant) in a cohort of D-/R- adult and pediatric SOT recipients receiving leukoreduced blood products not screened for CMV seronegativity transplanted at our center between 2000 and 2011. CMV infection was defined as IgG seroconversion or detectable CMV antigenemia/DNAemia. Among 536 consecutive D-/R- recipients, 398 (81.8%) had adequate follow-up, and 231 (58%) received cellular blood products (total: 1626 red blood cell units, 470 platelet units) 30 days pretransplant to 90 days posttransplant. We observed no confirmed TT-CMV cases, but 14 CA-CMV cases (64% symptomatic) were seen. The estimated incidence rate of CA-CMV was higher in children (3.0/100 patient years) than adults (0.46/100 patient years, incident rate ratio of 6.52). The absence of TT-CMV over 11 years suggests neither seronegative blood products nor CMV DNA blood donor screening would provide significant incremental safety when blood is already leukoreduced. D-/R- SOT recipients, particularly children, have a significantly higher and ongoing risk of CA-CMV.

Vestibular Evoked Myogenic Potential on Ocular, Cervical, and Soleus Muscles to Assess the Extent of Neurological Impairment in HTLV-1 Infection

Introduction: Vestibular Evoked Myogenic Potential (VEMP) can be used to test central vestibular pathways from the midbrain to the lumbar spine, according to the muscle tested.

Purpose: to compare the spinal cord alteration in individuals with HTLV-1-associated myelopathy (HAM) and with HTLV-1-asymptomatic infection using the VEMP recorded from different muscles.

Methods: VEMP was recorded in 90 individuals of whom 30 had HAM, 30 were HTLV-1 asymptomatic carriers, and 30 negative controls. VEMP was recorded in the oculomotor muscle (oVEMP), testing the vestibulo-ocular reflex, and in the cervical muscle (cVEMP) and soleus muscle (sVEMP), testing the vestibulospinal reflex, respectively, in the cervical and in the lumbar spinal level. The type of stimulation was auditory for oVEMP and cVEMP, and galvanic for sVEMP. The compared variables were the latencies of the electrophysiological waves.

Results: HTLV-1-asymptomatic group was similar to the controls regarding oVEMP (p = 0.461), but different regarding cVEMP (p < 0.001) and sVEMP (p < 0.001). HAM group has presented the worst latencies and was different from the HTLV-1-asymptomatic group in the VEMP of all the tested muscles (p < 0.001). The concomitant occurrence of VEMP alterations in the three recorded muscles of the same individual was found in 2 (6.7%) asymptomatic carriers and in 20 (66.7%) patients with HAM (p = 0.001). The analysis of VEMP alteration per group and per muscle has showed that, in HTLV-1-asymptomatic group, oVEMP was altered in 3 (10.0%) individuals, cVEMP in 10 (33.3%) and sVEMP in 13 (43.3%). In HAM group, oVEMP was altered in 23 (76.6%) individuals, cVEMP in 27 (90%), and sVEMP in 30 (100%).

Conclusion: HTLV-1-neurological damage has followed an ascendant progression beginning at the lumbar spine in the stage of a clinically asymptomatic infection, whereas HAM has affected not only the spine, but also the midbrain.

Case Report: Cognitive Impairment without Clinical Spinal Disease May Be the First Sign of HTLV-1 Neurological Alteration

Human t-cell lymphotropic virus type 1 (HTLV-1)-associated myelopathy (HAM) is a progressive neurological disease whose diagnosis is defined by clinical manifestations and seropositivity for HTLV-1 infection. Cognitive impairment (CI) is considered to occur after spinal impairment. A 51-year-old HTLV-1-infected man classified as an asymptomatic carrier presented difficulties in listening comprehension and executive memory. He was assessed for central auditory processing (CAP), cognition (event-related auditory evoked potential [P300]), and otoneurological functions (galvanic vestibular-evoked myogenic potential [gVEMP]). Altered responses were found in CAP, P300, and gVEMP, but the neurological examination and cognitive screening were normal. After a 2-year follow-up, we disclosed a positive Babinski sign, a mild CI, worsened P300, and gVEMP latencies, and the patient reported progressive lumbar pain and difficulty running. He was, then, reclassified as HAM. The first examination, in 2016, had already shown abnormal results in P300 and gVEMP despite the HTLV-1-asymptomatic carrier status. Therefore, tests that provide subclinical measures of neurological disease progression can be useful tools for an early diagnosis and intervention in HTLV-1 patients. Electrophysiological results had worsened as well as the clinical status and the cognitive function and the progression from asymptomatic status to an HTLV-1-associated neurological disease occurred within 2 years. Thus, HTLV-1-infected individuals with complaints of CI, hearing, or otoneurological manifestations should be submitted to neuropsychological and electrophysiological tests, allowing them to be properly cared in case of HAM progression.

Ocular vestibular evoked myogenic potential (VEMP) reveals mesencephalic HTLV-1-associated neurological disease

Purpose

Vestibular Myogenic Evoked Potential (VEMP) evaluates vestibulo-ocular and vestibulo-collic reflexes involved in the function of the otolithic organs and their afferent pathways. We compared the results of cervical and ocular VEMP in HTLV-1 associated myelopathy (HAM) and HTLV-1-asymptomatic infection.

Participants and methods

This cross-sectional study included 52 HTLV-1-infected individuals (26 HAM and 26 asymptomatic carriers) and 26 seronegative controls. The groups were similar regarding age and gender. Participants underwent simultaneous ocular and cervical VEMP. The stimulus to generate VEMP was a low-frequency tone burst sound tone burst, with an intensity of 120 decibels normalized hearing level, bandpass filter from 10 to 1,500 Hertz (Hz), with 100 stimuli at 500 Hz and 50 milliseconds recording time. The latencies of the electrophysiological waves P13 and N23 for cervical VEMP and N10 and P15 waves for ocular VEMP were compared among the groups. The absence or delay of the electrophysiological waves were considered abnormal results.

Results

Ocular VEMP was similar among the groups for N10 (p = 0.375) and different for P15 (p≤0.001). Cervical VEMP was different for P13 (p = 0.001) and N23 (p = 0.003). About ocular VEMP, in the HTLV-1-asymptomatic group, normal waves were found in 23(88.5%) individuals; in HAM group, normal waves were found in 7(26.9%). About cervical VEMP, 18(69.2%) asymptomatic carriers presented normal waves and only 3(11.5%) patients with HAM presented normal waves. Abnormalities in both VEMPs were found in 1(3.8%) asymptomatic carrier and in 16(61.5%) patients with HAM.

Conclusion

Neurological impairment in HAM was not restricted to the spinal cord. The mesencephalic connections, tested by ocular VEMP, have been also altered. Damage of the oculomotor system, responsible for eye stabilization during head and body movements, may explain why dizziness is such a frequent complaint in HAM.

Efficacy and safety of tranexamic acid usage in patients undergoing posterior lumbar fusion: a meta-analysis

Background

The purpose of this meta-analysis is to evaluate the efficacy and safety of tranexamic acid (TXA) for patients with degenerative lumbar disc herniation, stenosis or instability undergoing posterior lumbar fusion (PLF) surgery.

Methods

We searched PubMed, Embase, and Cochrane Library until May 1, 2018. Two reviewers selected studies, assessed quality, extracted data, and evaluated the risk of bias independently. Weighted mean difference (WMD) and relative risk (RR) were calculated as the summary statistics for continuous data and dichotomous data, respectively. We chose fixed-effects or random-effects models based on I² statistics. RevMan 5.0 and STATA 14.0 software were used for data analysis.

Results

Nine studies enrolling 713 patients for the study. The pooled outcomes demonstrated that TXA can decrease total blood loss (TBL) in patients underwent PLF surgery [WMD = -250.68, 95% CI (− 325.06, − 176.29), P<0.001], intraoperative blood loss (IBL) [WMD = -72.57, 95% CI (− 103.94, − 41.20), P<0.001], postoperative blood loss (PBL) [WMD = -127.57, 95% CI (− 149.39, − 105.75), P<0.001], and the loss of hemoglobin (Hb) in postoperative 24 h [WMD = -0.31, 95% CI (− 0.44, − 0.18), P<0.001]. However, there is no significant difference between two groups in transfusion rate [RR =0.34, 95% CI (0.09, 1.28), P = 0.11], and none thrombotic event was happened in the two groups.

Conclusion

Our meta-analysis demonstrated that TXA can decrease the Hb loss, TBL, IBL, PBL, and without increasing the risk of thrombotic event in patients with degenerative lumbar disc herniation, stenosis or instability underwent PLF surgery. However, there was no significant difference in blood transfusion rates between the two groups.

The long and winding road to pathogen reduction of platelets, red blood cells and whole blood

Pathogen reduction technologies (PRTs) have been developed to further reduce the current very low risks of acquiring transfusion-transmitted infections and promptly respond to emerging infectious threats. An entire portfolio of PRTs suitable for all blood components is not available, but the field is steadily progressing. While PRTs for plasma have been used for many years, PRTs for platelets, red blood cells (RBC) and whole blood (WB) were developed more slowly, due to difficulties in preserving cell functions during storage. Two commercial platelet PRTs use ultra violet (UV) A and UVB light in the presence of amotosalen or riboflavin to inactivate pathogens' nucleic acids, while a third experimental PRT uses UVC light only. Two PRTs for WB and RBC have been tested in experimental clinical trials with storage limited to 21 or 35 days, due to unacceptably high RBC storage lesion beyond these time limits. This review summarizes pre-clinical investigations and selected outcomes from clinical trials using the above PRTs. Further studies are warranted to decrease cell storage lesions after PRT treatment and to test PRTs in different medical and surgical conditions. Affordability remains a major administrative obstacle to PRT use, particularly so in geographical regions with higher risks of transfusion-transmissible infections.

Seroreactivity to Chikungunya and West Nile Viruses in Rwandan Blood Donors

Introduction: Chikungunya virus (CHIKV) and West Nile virus (WNV) have previously been reported from several African countries, including those bordering Rwanda where they may have originated. However, there have been no serosurveillance reports from Rwanda regarding these two viral pathogens. In this article, we present the first study of immunoglobulin G (IgG) seroreactivity of CHIKV and WNV in Rwandan blood donor samples. Methods: Blood donors from Rwanda (n = 874) and Sweden (n = 199) were tested for IgG reactivity against CHIKV, using an in-house enzyme-linked immunosorbent assay with the E1 envelope protein fused with p62 as antigen, and against WNV using a commercial kit. Data on mosquito distribution were obtained from the 2012 assessment of yellow fever virus circulation in Rwanda. Results: Seroreactivity to CHIKV was high in Rwanda (63.0%), when compared with Swedish donors, where only 8.5% were IgG positive. However, a cross-reactivity to O'nyong'nyong virus in neutralization test was noted in Rwandan donors. No significant difference in WNV seroreactivity was found (10.4% for Rwandan and 14.1% for Swedish donors). The relatively high seroreactivity to WNV among Swedish donors could partly be explained by cross-reactivity with tick-borne encephalitis virus prevalent in Sweden. Donors from the Eastern Province of Rwanda had the highest IgG reactivity to the two investigated viruses (86.7% for CHIKV and 33.3% for WNV). Five genera of mosquitoes were found in Rwanda where Culex was the most common (82.5%). The vector of CHIKV, Aedes, accounted for 9.6% of mosquitoes and this species was most commonly found in the Eastern Province. Conclusions: Our results showed high seroreactivity to CHIKV in Rwandan donors. The highest IgG reactivity to CHIKV, and to WNV, was found in the Eastern Province, the area reporting the highest number of mosquito vectors for these two viruses. Infection control by eliminating mosquito-breeding sites in population-dense areas is recommended, especially in eastern Rwanda.

First Report on Detection of Dengue Virus in the Donor Cornea

BACKGROUND

Dengue fever is the most prevalent form of flavivirus infection in humans. We have investigated whether corneoscleral tissue of the donor affected by dengue virus (DENV) harbors the virus.

PURPOSE

To identify the risk for viral transmission through corneal transplants in areas where DENV circulates.

METHODS

Excised corneoscleral tissue from a cadaver with a history of viral hemorrhagic fever was analyzed using reverse transcriptase-polymerase chain reaction for the presence of DENV and chikungunya virus (CHIV).

RESULTS

DENV was detected in RNA extracted from the donor corneoscleral rim. Further genotyping of the viral isolate from the virus-infected cell harvest revealed DENV type 3 as the causative agent. CHIV was not detected.

CONCLUSIONS

The data presented in this study recommend the implementation of polymerase chain reaction for detection of DENV and CHIV to analyze excised corneoscleral tissue of a donor with viral hemorrhagic fever.

Prevalence of serum markers of infection and naturally acquired immunity to hepatitis B virus in transfused children treated at a children's hospital in Salvador, Bahia: A cross-sectional study

The artificially acquired humoral immunity against hepatitis B virus (HBV) apparently may decline over the years. This study aimed to investigate the prevalence of naturally occurring serological markers of infection and active immunity to HBV in severely ill children and adolescents treated at the Martagão Gesteira Pediatric Hospital who received blood transfusions. The serum samples of 353 children who received poly-transfusions between August 2016 and March 2017 were tested for HBV surface antigen (HBsAg) markers, anti-HBc antibodies (IgG and IgM isotypes), and IgG anti-HBs. None of the children presented an outcome compatible with HBV infection. Three patients were seroreactive to markers of past infection, tested positive for anti-HBc IgG and negative for anti-HBc IgM, and were seropositive for anti-HBs, with antibody titers of >150.00 mIU/mL. Only 52.4% of the patients in the study were protected against HBV, with anti-HBs antibody titers of >10 mIU/mL. Children aged 5 years had lower titers of anti-HBs. The results indicated that the older children were more likely to be unprotected from HBV; this suggests the need to evaluate the vaccine response in children, especially those who received blood transfusions.

A systematic review of tranexamic acid usage in patients undergoing femoral fracture surgery

BACKGROUND

Patients undergoing femoral fracture surgery frequently require blood transfusion. Tranexamic acid (TXA) has been widely used to decrease transfusion rate in joint replacement surgery. Therefore, we conducted a systematic review to evaluate the efficacy and safety of TXA usage in femoral fracture surgery.

MATERIALS AND METHODS

Studies involving TXA usage in femoral fracture surgery were searched through four electronic databases. The end points included total blood loss, postoperative hemoglobin decline, transfusion rate, thromboembolic events, 90-day mortality, and operative time. The present study was performed following Cochrane Reviewers' Handbook and Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) statement and was carried out by using Stata 14.0 software.

RESULTS

Eleven studies concerning intravenous (IV) application of TXA and three studies concerning topical administration of TXA were included. Twelve studies were randomized controlled trials (RCTs), and one was a retrospective cohort study. Regarding IV TXA, our paper indicated that the IV TXA group had less total blood loss (weighted mean difference [WMD] = -319.282, P = 0.000), lower postoperative hemoglobin decline (WMD = -1.14, P = 0.000) and lower transfusion rate (risk difference [RD] = -0.172, P = 0.000). No significant differences were found in thromboembolic events (RD = 0.008, P = 0.507), 90-day mortality (RD = 0.009, P = 0.732) and operative time (WMD = -2.227, P = 0.103). Regarding topical TXA, no significant differences were found in the transfusion rate (RD = -0.098, P = 0.129), postoperative hemoglobin decline (WMD = -1.137, P = 0.231), thromboembolic events (RD = -0.017, P = 0.660) and operative time (WMD = -4.842, P = 0.136).

CONCLUSION

Our meta-analysis demonstrated that both IV and topical application of TXA reduced transfusion rate in femoral fracture surgery. However, still further studies are needed to identify the optimal route of administration, TXA dosage and timing. In addition, high-quality RCTs with a large sample size are required to figure out the safety of TXA application, especially in the elderly, before its wide recommendation.

Prevalence of hepatitis B virus, hepatitis C virus, and human immunodeficiency virus among blood donors of Mekelle blood bank, Northern Ethiopia: A three-year retrospective study

Blood transfusion services are a vital and integral part of modern healthcare services. However, the risk of transfusion transmittable infections (TTI) has been a major handicap. Therefore, this study was aimed at determining the prevalence of hepatitis B virus (HBV), hepatitis C virus (HCV), and human immunodeficiency virus (HIV) among blood donors. A retrospective study was conducted to collect data about the blood donors who consecutively donated blood from October 2011 to 2014. A three-year retrospective study was conducted in Mekelle Blood Bank. A data abstraction format was used to collect the sociodemographic and clinical data, and the prevalence of HBV, HCV, and HIV was determined. Data were analyzed using STATA version 10 analytical software. P value less than 0.05 was considered significant in all the analyses. A total of 10 728 blood donors, median (interquartile range) of age 30 (23-45) years and 3750 (34.9%) males were enrolled in this study. Of the participants 407(3.79%), 143(1.33%), and 111(1.03%) blood donors were positive for HBV, HCV, and HIV, respectively. HBV-HIV coinfections were found 10 (1.93%) blood donors, followed by HBV-HCV and HIV-HCV. A significant association between sex and marital status with HBV and HIV infection was found. However, significant association of HCV was observed among sex ( X ²  = 33.18, P < 0.001) and occupational ( X ²  = 84.33, P < 0.001). A significant percentage of HBV, HCV, and HIV among blood donors was observed. To select a donor and collect safe blood risk factors exposing blood donor should be studied, and community-based prevalence studies on TTI are also required.

[Assessment of virological quality of transfused blood in the town of Bukavu, South Kivu, Democratic Republic of Congo]

INTRODUCTION

In Bukavu, transfused blood is selected using rapid diagnostic tests (RDTs). These tests are easily performed without specialized equipments. This study aims to evaluate the virological quality of transfused blood assessed using rapid diagnostic tests.

METHODS

A blood sample was drawn from a blood bag and collected in a 4ml dry tube in 5 Health Care Facilities over a month. Counter analysis was performed on each sample using rapid tests and ELISA. Intrinsic and extrinsic values were calculated. Cohen's kappa coefficient was used to evaluate the reliability of RDT compared with ELISA.

RESULTS

Three hundred and twelve samples were collected; 5 samples were positive for one or the other virologic marker while 307 samples were negative in all the tests. However Elisa showed, out of the 307 samples which were RDT test negative, 15 other positive samples including 3 samples positive for HIV, 3 for HCV and 9 for HBV. In addition, ELISA validated some RDT-positive samples and contradicted other results. Sensitivity and positive predictive value from rapid diagnostic tests were very low. The reliability of these tests was satisfactory, medium or low.

CONCLUSION

Blood assessed using RDTs poses a non negligible risk of viral infections. This study highlights the need for more reliable and efficient tests in our Health Care Facilities.

Seroepidemiology of Cytomegalovirus Infection in Pregnant Women in the Central Mexican City of Aguascalientes

Background

Infection with cytomegalovirus (CMV) during pregnancy may lead to congenital disease. Very little is known about the seroepidemiology of CMV infection in pregnant women in Mexico. We sought to determine the seroprevalence and correlates of CMV infection in pregnant women in Aguascalientes City, Mexico.

Methods

Through a cross-sectional study design, 289 pregnant women were examined for anti-CMV IgG and IgM antibodies in Aguascalientes City, Mexico. A standardized questionnaire was used to obtain the socio-demographic, clinical and behavioral characteristics of the pregnant women. The association between CMV infection and the characteristics of the pregnant women was assessed by bivariate and multivariate analyses.

Results

Anti-CMV IgG antibodies were detected in 259 (89.6%) of the 289 pregnant women studied. None of the 289 pregnant women were positive for anti-CMV IgM antibodies. Seroprevalence of CMV infection was significantly lower (P = 0.03) in pregnant women with reflex impairment (5/8: 62.5%) than in those without this clinical feature (246/272: 90.4%). Seroprevalence of CMV infection was significantly higher (P = 0.03) in pregnant women with 2 - 9 pregnancies (140/150: 93.3%) than in those with only one pregnancy (119/139: 86.2%). Logistic regression analysis of socio-demographic and behavioral variables showed that seropositivity to CMV was associated with contact with children (odds ratio (OR) = 3.56; 95% confidence interval (CI): 1.17 - 10.84; P = 0.02), whereas high (> 150 AU/mL) anti-CMV antibody levels were negatively associated with washing hands before eating (OR = 0.17; 95% CI: 0.05 - 0.63; P = 0.007).

Conclusions

We found a high endemicity of CMV infection in pregnant women in Aguascalientes City, Mexico. Factors associated with CMV infection found in this study may be useful for an optimal planning of preventive measures against CMV exposure in pregnant women.

Cost-utility and budget impact of methylene blue-treated plasma compared to quarantine plasma

BACKGROUND

Methylene blue and visible light treatment and quarantine are two methods used to reduce adverse events, mostly infections, associated with the transfusion of fresh-frozen plasma. The objective of this study was to estimate and compare the budget impact and cost-utility of these two methods from a payer's perspective.

MATERIALS AND METHODS

A budget impact and cost-utility model simulating the risks of hepatitis B virus, hepatitis C virus, cytomegalovirus, a West Nile virus-like infection, allergic reactions and febrile non-haemolytic transfusion reactions achieved using plasma treated with methylene blue and visible light (MBP) and quarantine plasma (QP) was constructed for Spain. QP costs were estimated using data from one blood centre in Spain and published literature. The costs of producing fresh-frozen plasma from whole blood, apheresis plasma, and multicomponent apheresis, and separately for passive and active methods of donor recall for QP were included. Costs and outcomes over a 5-year and lifetime time horizon were estimated.

RESULTS

Compared to passive QP, MBP led to a net increase of € 850,352, and compared to active QP, MBP led to a net saving of € 5,890,425 over a 5-year period. Compared to passive QP, MBP increased the cost of fresh-frozen plasma per patient by € 7.21 and had an incremental cost-utility ratio of € 705,126 per quality-adjusted life-year. Compared to active QP, MBP reduced cost by € 50.46 per patient and was more effective.

DISCUSSION

Plasma collection method and quarantine approach had the strongest influence on the budget impact and cost-utility of MBP. If QP relies on plasma from whole blood collection and passive quarantine, it is less costly than MBP. However, MPB was estimated to be more effective than QP in all analyses.

Detection of Merkel Cell Polyomavirus DNA in Serum Samples of Healthy Blood Donors

Merkel cell polyomavirus (MCPyV) has been detected in 80% of Merkel cell carcinomas (MCC). In the host, the MCPyV reservoir remains elusive. MCPyV DNA sequences were revealed in blood donor buffy coats. In this study, MCPyV DNA sequences were investigated in the sera (n = 190) of healthy blood donors. Two MCPyV DNA sequences, coding for the viral oncoprotein large T antigen (LT), were investigated using polymerase chain reaction (PCR) methods and DNA sequencing. Circulating MCPyV sequences were detected in sera with a prevalence of 2.6% (5/190), at low-DNA viral load, which is in the range of 1–4 and 1–5 copies/μl by real-time PCR and droplet digital PCR, respectively. DNA sequencing carried out in the five MCPyV-positive samples indicated that the two MCPyV LT sequences which were analyzed belong to the MKL-1 strain. Circulating MCPyV LT sequences are present in blood donor sera. MCPyV-positive samples from blood donors could represent a potential vehicle for MCPyV infection in receivers, whereas an increase in viral load may occur with multiple blood transfusions. In certain patient conditions, such as immune-depression/suppression, additional disease or old age, transfusion of MCPyV-positive samples could be an additional risk factor for MCC onset.

Emerging Infectious Diseases and Blood Safety: Modeling the Transfusion-Transmission Risk

While the transfusion-transmission (TT) risk associated with the major transfusion-relevant viruses such as HIV is now very low, during the last 20 years there has been a growing awareness of the threat to blood safety from emerging infectious diseases, a number of which are known to be, or are potentially, transfusion transmissible. Two published models for estimating the transfusion-transmission risk from EIDs, referred to as the Biggerstaff-Petersen model and the European Upfront Risk Assessment Tool (EUFRAT), respectively, have been applied to several EIDs in outbreak situations. We describe and compare the methodological principles of both models, highlighting their similarities and differences. We also discuss the appropriateness of comparing results from the two models. Quantitating the TT risk of EIDs can inform decisions about risk mitigation strategies and their cost-effectiveness. Finally, we present a qualitative risk assessment for Zika virus (ZIKV), an EID agent that has caused several outbreaks since 2007. In the latest and largest ever outbreak, several probable cases of transfusion-transmission ZIKV have been reported, indicating that it is transfusion-transmissible and therefore a risk to blood safety. We discuss why quantitative modeling the TT risk of ZIKV is currently problematic.

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During the last 20 years there has been a growing awareness of the threat to blood safety from emerging infectious diseases (EIDs), a number of which are known to be, or are potentially, transfusion-transmissible.

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The transfusion-transmission risk of EID agents can be estimated by risk modeling which can form an important part of risk assessments and inform decisions regarding risk mitigation strategies.

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We describe and compare the methodological principles of two published risk models for estimating the transfusion transmission risk of EIDs.

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We use Zika virus as a case study to demonstrate that reliable risk modeling for EID agents can be problematic due to the uncertainty of the input parameters.

Efficacy and safety of intravenous tranexamic acid administration in patients undergoing hip fracture surgery for hemostasis: A meta-analysis

BACKGROUND

Patients undergoing hip fracture surgery frequently require blood transfusion. Tranexamic acid (TXA) has been widely used to decrease blood loss and transfusion rates in joint replacement surgery. Therefore, we conducted a meta-analysis to evaluate efficacy and safety of intravenous TXA administration in patients suffering from hip fractures.

METHODS

Electronic databases were searched before December 2016 by 2 independent reviewers, including Cochrane Library, EMBASE, PubMed, Web of Science, the Chinese Biomedical Literature database, and the China National Knowledge Infrastructure databases. Randomized controlled trials (RCTs) involving the efficacy and safety of intravenous (IV) TXA in patients who underwent hip surgery were included in our meta-analysis. The endpoints included total blood loss, hidden blood loss, postoperative hemoglobin decline, transfusion rates, the rate of thrombotic events, and operative time. Current meta-analysis was performed following the guidelines of the Cochrane Reviewer's Handbook and the PRISMA statement. The pooling of data was carried out using STATA V.12.0 software.

RESULT

Eight RCTs were included, involving 598 participants. Current meta-analysis indicated that the IV TXA group had less total blood loss (weighted mean difference [WMD] = -277, 95%CI: -335 to -220, P = .000), less hidden blood loss (WMD = -246, 95%CI: -252 to -241, P = .000), lower postoperative hemoglobin decline (WMD = -1.36, 95% CI: -1.84 to -0.88, P = .000), and lower transfusion rates (risk difference [RD] = -0.19, 95% CI: -0.27 to -0.11, P = .000) compared to the control group. No significant differences were found regarding the rate of thrombotic events (RD = 0.02, 95% CI: = -0.01 to 0.05, P = .262) and operative time (WMD = -0.7, 95% CI: -3.3 to 1.9, P = .6).

CONCLUSION

It was well established that systemic administration of TXA could reduce blood loss and transfusion rates in hip fracture surgery. But the optimal regimen, dosage, and timing still need a further research. In addition, more large and high-quality randomized controlled studies are needed to focus on the safety of IV TXA application before its wide recommendation for use in hip fracture surgery.

Seroprevalence of anti-WNV IgG antibodies and WNV-RNA in Egyptian blood donors

Transmission of West Nile virus (WNV) from asymptomatic donors has been reported during blood transfusions and organ transplants in humans. In this work, we aimed to investigate the presence of WNV antibody and WNV RNA in blood donors to evaluate the sero-prevalence of WNV and risk for WNV transmission. One hundred and sixty blood donors were tested for the presence of anti-WNV IgG by ELISA and for WNVs 1 and 2 RNA by RT-PCR. About 55% of blood donors were seropositive for WNV IgG antibodies, with significantly higher percentage of positive donors coming from rural areas and Nile Delta region compared to other donors. Using RT-PCR all donors were negative for viral RNA of both WNV lineages 1 and 2. High sero-prevelance of WNV antibodies in asymptomatic blood donors denotes endemicity of the WNV in Egypt and points to the importance of routine screening of blood donors for WNV RNA. On the other hand the absence of WNV RNA by RT-PCR indicates apparent low risk of the blood products as regards WNV transmission. Further studies into significance of WNV seronegativity among Rh negative donors and into the use of WNV seropositive blood in prophylaxis or treatment of WNV neuroinvasive disease are recommended. J. Med. Virol. 89:1323-1329, 2017. © 2017 Wiley Periodicals, Inc.

Combined application versus topical and intravenous application of tranexamic acid following primary total hip arthroplasty: a meta-analysis

Background

The use of intravenous (IV) or topical tranexamic acid (TXA) in total hip arthroplasty has been proven to be effective and safe in total hip arthroplasty. However, which of these two administration routes is better has not been determined. The combined administration of TXA has been used in total knee arthroplasty with satisfactory results. We hypothesized that combined application of TXA may be the most effective way without increased rate of thrombotic events such as deep vein thrombosis (DVT) and pulmonary embolisms (PE) in patients subjected to primary total hip replacement (THA). A meta-analysis was conducted to compare the efficacy and safety of the combined use of tranexamic acid (TXA) relative to topical or intravenous (IV) use alone for treatment of primary THA. The outcomes included total blood loss, postoperative hemoglobin decline, transfusion rates, and the incidence rates of deep vein thrombosis (DVT) and pulmonary embolisms (PE).

Methods

We searched electronic databases including PubMed, EMBASE, the Cochrane Library, Web of Science, the Chinese Biomedical Literature database, the CNKI database, and Wanfang Data until September 2016. The references of the included articles were also checked for additional potentially relevant studies. There were no language restrictions for the search. The data of the included studies were analyzed using RevMan 5.3 software.

Results

Seven studies met the inclusion criteria, encompassing a total of 1762 patients. Our meta-analysis demonstrated that total blood loss, postoperative hemoglobin decline, and transfusion rates were significantly lower for patients that received the combined treatment compared to patients that received either topical or intravenous administration of TXA. No statistical differences were found in the incidence of deep venous thrombosis (DVT) or pulmonary embolism (PE).

Conclusion

The group that received the combined treatment had lower total blood loss, postoperative hemoglobin decline, and transfusion rates without an increased rate of thrombotic events (DVT or PE). The topical or intravenous use of TXA in primary THA is generally considered to be safe and effective. This meta-analysis demonstrated that combined TXA application may be superior to topical or intravenous application of TXA alone. However, larger, high-quality randomized control trials are required for greater confidence in this finding.

Combined use of intravenous and topical tranexamic acid following cementless total hip arthroplasty: a randomised clinical trial

PURPOSE

This study was designed to compare the efficacy and safety of the combined use of tranexamic acid (TXA) with the intravenous (IV) or local use alone in total hip arthroplasty (THA).

METHODS

210 patients were randomised to a IV group, a local group or a combined group. Participants received 1.5 g IV-TXA in the IV group, 3 g local TXA in the local group, or 1 g IV-TXA combined with 2 g local TXA in the combined group. The primary outcomes were total blood loss (TBL), maximum haemoglobin drop, and the incidence of deep venous thrombosis (DVT) and pulmonary embolism (PE).

RESULTS

TBL was (776.75 ± 188.95) ml in the combined group, which was significantly lower than in the IV group or the local group (p = 0.015, p = 0.001 respectively). Likewise, the mean values of maximum hemoglobin drop in the combined, IV, and local groups were 2.98 ± 0.78, 3.36 ± 0.78, and 3.89 ± 0.72 g/dL, respectively, with a significant intergroup difference (p&lt;0.001 for all). Asymptomatic DVT was detected in 1 patient of the IV group, and 2 patients of the combined group with the use of ultrasound. There were no episodes of PE, and no significant differences were seen between groups in terms of complications.

CONCLUSIONS

Combined use of intravenous TXA and local TXA in primary unilateral THA can effectively decrease total blood loss and increase postoperative haemoglobin levels without influencing complication rates. It is suggested that this combined TXA regimen is more effective in decreasing blood loss in cementeless THA than intravenous or local administration alone.

Intravenous versus topical tranexamic acid in primary total hip replacement: A meta-analysis

BACKGROUND

As the prevalence of total hip arthroplasty (THA) is increasing, it is usually associated with considerable blood loss. Tranexamic acid (TXA) has been reported to reduce perioperative blood loss in hip joint arthroplasty. But the best route of TXA administration continues to be controversial. So, we conducted a meta-analysis that integrated all data from the 7 included trials to compare the effectiveness and safety of topical and intravenous TXA administration in primary THA. The endpoints assessed in this meta-analysis include the comparisons of total blood loss, postoperative hemoglobin decline, transfusion rates, the incidence rate of deep vein thrombosis (DVT), pulmonary embolisms (PE), and wound infection.

METHODS

Literature searches of PubMed, EMBASE, the Cochrane Library, the Chinese Biomedical Literature database, the CNKI database, and Wan Fang Data were performed up to August 30, 2016. Randomized controlled trials (RCTs) were included in our meta-analysis if they compared the efficiency and safety of intravenous versus topical administration of TXA in patients who underwent primary THA. The endpoints included the comparisons of total blood loss, postoperative hemoglobin decline, transfusion rates, the incidence rate of DVT, PE, and wound infection. A meta-analysis was performed following the guidelines of the Cochrane Reviewer's Handbook and the PRISMA statement. The pooling of data was carried out by using RevMan 5.3, Denmark.

RESULTS

Seven RCTs involving 964 patients met the inclusion criteria. Our meta-analysis indicated that there were no significant differences in the 2 groups in terms of total blood loss ([mean difference (MD) = -14.74, 95% confidence interval (CI): -89.21 to 59.74, P = 0.7], transfusion rates [RD = -0.02, 95% CI: -0.05 to 0.02, P = 0.39]; no significant differences were found regarding the incidence of adverse effects such as deep venous thrombosis [DVT] [RD = 0.00, 95% CI: -0.01 to 0.01, P = 1.00], PE [RD = 0.00, 95% CI: -0.01 to 0.01, P = 0.71], or wound infection [RD = -0.01, 95% CI: -0.06 to 0.04, P = 0.66]). The pooled results showed that the intravenous groups had a lower postoperative hemoglobin decline (MD = -0.47, 95% CI: -0.74 to -0.20, P = 0.0006). It was probably due to insufficient data and the varied reporting of outcomes. There was some inherent heterogeneity due to the small sample size of each primary study.

CONCLUSION

The topical and intravenous administrations of TXA have a similar effect on the decrease of blood loss without an increased risk of complications (DVT, PE, and wound infection). Intravenous TXA administration may have a maximum efficacy. Topical TXA administration may be preferred in patients who with high risk of thromboembolic events. However, larger, high-quality RCTs are required to explore the optimal regimen, dosage, timing still in the future in order to recommend TXA widespread use in total joint arthroplasty.

Low dose tranexamic acid reduces blood transfusion rate after total knee arthroplasty: A population-based study in Taiwan

BACKGROUND/PURPOSE

Previous reports, mostly small clinical trials conducted in USA or Europe, indicated that tranexamic acid (TXA) would be effective for reducing blood transfusions after total knee arthroplasty (TKA). However, large scale studies are needed regarding the effectiveness and safety issue of complication events following TKA, especially for the Asian population. We aimed to evaluate the efficacy and safety of TXA use based on data from an elderly population in Taiwan.

METHODS

This was a retrospective population-based study using an inpatient dataset from the nationwide health insurance research database in Taiwan. Patients aged >65 years with a diagnosis of osteoarthritic knee in 2012 were included (n = 10,321). A low-dose intravenous form of TXA (250-1000 mg) was identified perioperatively during the TKA. The surgical outcomes of interest were allogeneic red blood cell transfusion and postoperative 30-day complications.

RESULTS

A total of 1205 (11.7%) patients received TXA. Based on a multilevel logistic regression model, we found a 47% odds reduction of blood transfusion without elevating the complications of infection and vascular-related diseases. Furthermore, the drug effect in reducing transfusion was different among hospital levels, and medical centers had a relatively lower transfusion rate.

CONCLUSION

The use of perioperative TXA was an efficient strategy to prevent blood loss after TKA.

Glycine and Folate Ameliorate Models of Congenital Sideroblastic Anemia

Sideroblastic anemias are acquired or inherited anemias that result in a decreased ability to synthesize hemoglobin in red blood cells and result in the presence of iron deposits in the mitochondria of red blood cell precursors. A common subtype of congenital sideroblastic anemia is due to autosomal recessive mutations in the SLC25A38 gene. The current treatment for SLC25A38 congenital sideroblastic anemia is chronic blood transfusion coupled with iron chelation. The function of SLC25A38 is not known. Here we report that the SLC25A38 protein, and its yeast homolog Hem25, are mitochondrial glycine transporters required for the initiation of heme synthesis. To do so, we took advantage of the fact that mitochondrial glycine has several roles beyond the synthesis of heme, including the synthesis of folate derivatives through the glycine cleavage system. The data were consistent with Hem25 not being the sole mitochondrial glycine importer, and we identify a second SLC25 family member Ymc1, as a potential secondary mitochondrial glycine importer. Based on these findings, we observed that high levels of exogenous glycine, or 5-aminolevulinic acid (5-Ala) a metabolite downstream of Hem25 in heme biosynthetic pathway, were able to restore heme levels to normal in yeast cells lacking Hem25 function. While neither glycine nor 5-Ala could ameliorate SLC25A38 congenital sideroblastic anemia in a zebrafish model, we determined that the addition of folate with glycine was able to restore hemoglobin levels. This difference is likely due to the fact that yeast can synthesize folate, whereas in zebrafish folate is an essential vitamin that must be obtained exogenously. Given the tolerability of glycine and folate in humans, this study points to a potential novel treatment for SLC25A38 congenital sideroblastic anemia.

Mutations in the SLC25A38 gene cause an inherited anemia. In this study we determine that the function of SLC25A38, and its yeast homolgue Hem25, is to act as mitochondrial glycine importers providing a molecular explanation for why patients with SLC25A38 mutations have low hemoglobin levels and become anemic. Using this new knowledge, we go on to determine that supplementation with glycine and folate restore hemoglobin levels in a zebrafish model of the disease pointing to a potentially new, safe, and cost effective treatment for SLC25A38 congenital sideroblastic anemia.

An In Vivo Study of Low-Dose Intra-Articular Tranexamic Acid Application with Prolonged Clamping Drain Method in Total Knee Replacement: Clinical Efficacy and Safety

Background. Recently, combined intra-articular tranexamic acid (IA-TXA) injection with clamping drain method showed efficacy for blood loss and transfusion reduction in total knee replacement (TKR). However, until now, none of previous studies revealed the effect of this technique on pharmacokinetics, coagulation, and fibrinolysis. Materials and Methods. An experimental study was conducted, during 2011-2012, in 30 patients undergoing unilateral TKR. Patients received IA-TXA application and then were allocated into six groups regarding clamping drain duration (2-, 4-, 6-, 8-, 10-, and 12-hours). Blood and drainage fluid were collected to measure tranexamic acid (TXA) level and related coagulation and fibrinolytic markers. Postoperative complication was followed for one year. Results. There was no significant difference of serum TXA level at 2 hour and 24 hour among groups (p < 0.05). Serum TXA level at time of clamp release was significantly different among groups with the highest level at 2 hour (p < 0.0001). There was no significant difference of TXA level in drainage fluid, postoperative blood loss, blood transfusion, and postoperative complications (p < 0.05).  Conclusions. Low-dose IA-TXA application in TKR with prolonged clamping drain method is a safe and effective blood conservative technique with only minimal systemic absorption and without significant increase in systemic absorption over time.

Characterization of Acute and Chronic Hepatitis B Virus Genotypes in Canada

Objective

The prevalence and distribution of hepatitis B virus (HBV) genotypes in Canada is not known. Genotypic analysis may contribute to a better understanding of HBV strain distribution and transmission risk.

Methods

HBV surface antigen (HBsAg) positive samples of acute (n = 152) and chronic (n = 1533) HBV submitted for strain analysis or reference genotype testing between 2006 and 2012 were analyzed. The HBsAg coding region was amplified to determine the HBV genotype by INNO-LiPA assay or sequence analysis. Single and multivariate analyses were used to describe genotypes’ associations with known demographic and behavioral risk factors for 126 linked cases of acute HBV.

Results

Nine genotypes were detected (A to I), including mixed infections. Genotype C (HBV/C) dominated within chronic infections while HBV/D and A prevailed among acute HBV cases. History of incarceration and residing with a chronic HBV carrier or injection drug user were the most frequently reported risks for acute HBV infection. Over time, HBV/A increased among both acute and chronic infections, and HBV/C and HBV/D decreased among chronic infections.

Conclusion

Chronic and acute HBV genotypes in Canada differ in the relative distribution and their associations with known risk factors, suggesting different routes of transmission and clinical progression of infection.

Electrophysiological analysis shows dizziness as the first symptom in human T cell lymphotropic virus type-associated myelopathy/tropical spastic paraparesis

Dizziness is a symptom in human T cell lymphotropic virus type-associated myelopathy/tropical spastic paraparesis (HAM/TSP) and may occur due to vestibulospinal tract dysfunction. This tract can be assessed by an electrophysiological test called vestibular-evoked myogenic potential (VEMP). The aim was to correlate the result of VEMP generated by acoustic stimuli and dizziness in individuals with human T cell lymphotropic virus type 1 (HTLV-1)-asymptomatic infection and HAM/TSP. VEMP was recorded from the sternocleidomastoid muscle of 60 HTLV-1-negative adults (60±8 years) and 60 individuals infected with HTLV-1, 30 being asymptomatic (59±8 years) and 30 with HAM/TSP (59±8 years). In all groups, 90% of the participants were women. VEMP was generated by acoustic stimuli (short tone bursts), with an intensity of 118 dBHL and band-pass filter from 10 Hz to 1,500 Hz, and presented 200 stimuli at a frequency of 1,000 Hz with a record time of 60 ms. Of 60 HTLV-1-negative individuals, 14 (23%) reported dizziness; VEMP was normal in all. In the HTLV-1-asymptomatic group, 11(37%) complained of dizziness (p=0.31); VEMP was altered in four (40%) subjects with dizziness and in one (5%) without dizziness (p=0.00). In the group with HAM/TSP, dizziness was reported by 17 (57%) subjects (p=0.002); VEMP was altered in 11 (64%) with dizziness and in 5 (38%) without dizziness (p=0.15). Dizziness without an apparent etiology in HTLV-1-asymptomatic carriers deserves attention in terms of a possible subclinical spinal cord involvement that can be clarified through spinal electrophysiological tests. Damage of the vestibulospinal tract seems to occur in the early stages of HAM/TSP.

Does tranexamic acid alter the risk of thromboembolism following primary total knee arthroplasty with sequential earlier anticoagulation? A large, single center, prospective cohort study of consecutive cases

INTRODUCTION

In order to decrease the blood loss and transfusion requirement, tranexamic acid (TXA) has attracted the public's attention in total knee arthroplasty (TKA). However, the safety profile of TXA hindered its wide adoption. And the balance of anti-coagulation sequential anti-fibrinolysis has not yet been explored. This large, single center, prospective cohort study of consecutive cases aimed to investigate the epidemiology of vascular occlusive events associated with TXA and introduce our preliminary results of novel thromboprophylaxis.

MATERIALS AND METHODS

We prospectively collected patients' data of our institution through National Health Database. The primary outcome was the incidence of venous thromboembolism and mortality within 30days following primary TKA. Subgroup analysis was performed on the basis of TXA administration methods.

RESULTS

During 2012 to 2014, a total of 2532 unilateral TKA procedures were conducted in our institution, 2222 with TXA, 310 without TXA. The total occurrence of vascular occlusive events was statistically significantly higher (17.55% Vs 9.35%, p<0.001) in the TXA group but this finding was confined to the calf veins, with the main difference being the incidence in the calf muscular veins (13.68% Vs 6.77%, p=0.001). Statistical difference was not detected neither in the incidence of symptomatic DVT nor asymptomatic DVT. No episode of symptomatic PE and all-cause mortality within 30days occurred postoperatively. Subgroup analysis revealed no significant difference with regard to the incidence of DVT (p>0.05).

CONCLUSION

This study confirmed that the incidence of postoperative VTE was unchanged when TXA was administered in primary unilateral TKA. And our study further indicated that earlier anticoagulation should be adopted to keep the balance between anti-fibrinolysis and anti-coagulation after administering TXA.

Is transfusion-transmitted dengue fever a potential public health threat?

Dengue is an arboviruses due to single-stranded enveloped ribonucleic acid viruses, named dengue viruses (DENV), that include four serotypes and are mainly transmitted via the bite of mosquitoes of the genus Aedes (A. aegypti and A. albopictus). The distribution of the disease was historically limited to intertropical areas; however, during the last thirty years, the perimeter of the disease extended considerably and temperate areas are now at risk of outbreaks. The present global burden of dengue is considerable: 2.5 billion people over more than 100 countries are concerned; 50 to 100 million infections occur every year, with a number of fatal cases of approximately 20000. Although frequently asymptomatic or limited to a mild fever, dengue is responsible for severe cases mainly consecutive to the occurrence of hemorrhagic complications that can lead to shock and death, notably in children from poor-resource settings. The place of DENV as a transfusion-transmitted pathogen has been recognized only in 2008. At the present time, only five cases of transfusion-transmitted dengue, including one case of dengue hemorrhagic fever, have been formerly documented. This review provides a general overview of dengue, its viruses and their vectors. It replaces the disease in the context of other viral diseases transmitted by arthropods. It discusses the threat of dengue on the supply of blood products in endemic and non endemic areas. Finally, it describes the specific and non specific measures available for improving the security of blood products with regards to this emerging risk. Interestingly, in 2009, the American Association of Blood Banks placed DENV in the highest category of emerging infectious agents for their potential impact on transfusion recipient safety for the next years in North America.

Head-to-head comparison between two screening systems for HBsAG, anti-HBc, anti-HCV and HIV combination immunoassays in an international, multicentre evaluation study

BACKGROUND

Mandatory screening of blood donations for hepatitis B and hepatitis C viruses and human immunodeficiency viruses 1 and 2 requires assays with exceptional sensitivity and specificity. This study reports the results from a direct head-to-head comparison of the Elecsys HBsAG II, Elecsys Anti-HBc, Elecsys Anti-HCV II and Elecsys HIV combi PT immunoassays with the respective ABBOTT PRISM/Architect instrument immunoassays in a multicentre blood bank evaluation study.

STUDY DESIGN AND METHODS

Assay validation was performed in the blood screening laboratories of four blood bank centres in Austria, Germany, Spain and Thailand, where both first-time donor samples (approximately 6000 donors) and repeat donor samples (approximately 14,000 donors) were screened.

RESULTS

Of all screened donor samples, 93 (0.46%) were confirmed to be positive using assays from both manufacturers. The specificity of all immunoassays was >99.5% and was comparable between first-time and multiple-time donors. A direct comparison between the assays from Roche and ABBOTT according to Bland and Altman analysis demonstrated equivalent quality.

CONCLUSIONS

These results suggest that the Elecsys immunoassays for HBV, HCV and HIV infection, with a comparative sensitivity of 100% and a specificity exceeding the common technical specification threshold of >99.5%, meet the stringent performance criteria stipulated for blood donor screening for these infectious agents. Significant differences in the specificity between first-time and repeat donors were not detectable.

Detection of Plasmodium knowlesi DNA in the urine and faeces of a Japanese macaque (Macaca fuscata) over the course of an experimentally induced infection

Background

Diagnostic techniques based on PCR for the detection of Plasmodium DNA can be highly sensitive and specific. The vast majority of these techniques rely, however, on the invasive sampling of blood from infected hosts. There is, currently, considerable interest in the possibility of using body fluids other than blood as sources of parasite DNA for PCR diagnosis.

Methods

Urine and faeces were obtained from a Plasmodium knowlesi infected-Japanese macaque (Macaca fuscata) over the course of an experimentally induced infection. P. knowlesi DNA (PkDNA) extracted from urine and faeces were monitored by nested PCR targeting the P. knowlesi specific cytochrome b (cytb) gene.

Results

Urinary PkDNA was detected on day 2, but was not amplified using DNA templates extracted from the samples on day 4, day 5 and day 6. Subsequently, urinary PkDNA was detected from day 7 until day 11, and from day 20 until day 30. PkDNA in faeces was detected from day 7 until day 11, and from day 20 until day 37. Moreover, real-time quantitative PCR showed a remarkable increase in the amount of urinary PkDNA following anti-malarial treatment. This might have been due to the release of a large amount of PkDNA from the degraded parasites as a result of the anti-malarial treatment, leading to excretion of PkDNA in the urine.

Conclusions

The cytb-PCR system using urine and faecal samples is of potential use in molecular epidemiological surveys of malaria. In particular, monkey faecal samples could be useful for the detection of zoonotic primate malaria in its natural hosts.

Electronic supplementary material

The online version of this article (doi:10.1186/1475-2875-13-373) contains supplementary material, which is available to authorized users.

Screening tests for hepatitis B virus, hepatitis C virus, and human immunodeficiency virus in blood donors: evaluation of two chemiluminescent immunoassay systems

Automated chemiluminescent immunoassays (CLIAs) are useful for the detection of hepatitis B virus (HBV), hepatitis C virus (HCV), and human immunodeficiency virus 1/2 antigen/antibodies (HIV 1/2 Ag/Ab) in blood donor screening. Eight hundred and forty serum samples were tested for hepatitis B surface antigen (HBsAg), HCV antibodies (anti-HCV), and HIV1/2 Ag/Ab in parallel using 2 different CLIAs (Abbott Architect i2000SR and Roche Cobas e411). The concordance between the 2 systems was high (Cohen's kappa 0.97 for HBsAg, 0.77 for anti-HCV, 0.92 for HIV1/2 Ag/Ab) and the specificity and the positive predictive value were comparable. Among the 12 discrepant results, 11 were false-positive and 1 (reactive by Architect) was true-positive for anti-HCV. Positivity for HBV DNA, HCV RNA, and HIV RNA was recorded in 90.9%, 38.9%, and 100% of true-positive samples, respectively. This study represents the first stringent comparison between Architect i2000SR and Cobas e411 in blood donors. We observed a good correlation and high agreement among HBV, HCV, and HIV with the 2 automated systems.

Antibodies reacting with Simian virus 40 mimotopes in serum samples from patients with thalassaemia major

BACKGROUND

Simian virus 40 (SV40) is a small DNA tumour virus. Footprints of the virus have been detected in different humam lymphoproliferative disorders and in blood specimens of blood from healthy blood donors. This study was carried out to verify whether SV40 antibodies can be detected in serum samples from multiply transfused patients with thalassaemia major.

MATERIALS AND METHODS

An indirect enzyme-linked immunosorbent assay was employed, using SV40 specific synthetic peptides mimicking the antigens of the viral capsid proteins 1-2-3, to test for the presence of antibodies to SV40 in serum samples taken from patients affected by transfusion-dependent thalassaemia major (n=190) and healthy blood donors (n=251).

RESULTS

The prevalence of antibodies against SV40 was higher in patients than in controls (24% vs 17%). The prevalence increased and was significantly higher in the older age group of patients affected by thalassemia major than in controls (38% vs 20%, p<0.04).

DISCUSSION

The higher prevalence of serum antibodies against simian virus 40 in older, multiply transfused patients with thalassamia major than in controls suggests that this virus, or a closely related yet unknown human polyomavirus, could have been transmitted in the past by transfusion with whole blood. At the same time, our data indicate no significant differences in prevalence of SV40 antibodies in patients and controls of younger age thus suggesting that current transfusion methods with leucodepletion and filtered red cells are safe.

Epidemiology of infections in cancer patients

Although major advances in the care of cancer patients over the past several decades have resulted in improved survival, infectious complications remain a significant cause of morbidity and mortality. To successfully identify, treat, and prevent infections, a comprehensive understanding of risk factors that predispose to infection and of commonly encountered pathogens is necessary. In addition, clinicians must keep abreast of the changing epidemiology of infections in this population. As therapeutic modalities continue to evolve, as established pathogens become increasingly drug resistant, and as new pathogens are discovered, successful management of infections will continue to present challenges in the years to come.

[Reality and importance of transfusion-transmitted malaria in a stable endemic context: Cotonou case in Benin]

Malaria endemic status of our countries supports avoiding malaria screening for the blood qualification. But this attitude makes young children, pregnant women and people without semi-immunity incur a high risk of malaria. The goal of the survey was to value the reality and the importance of transfusion-transmitted malaria and to assess its determining factors. The study included 141 packed-red-cells units transfused to 77 hospitalized recipients, not suffering from malaria and not having been transfused the last two weeks. Every packed-red-cells assigned to a patient was tested for malaria before use. Thick and thin blood film were performed 96hours after transfusion. A clinical follow-up was undertaken as well as in the hospital and at home after release. In all, 13.47% of the transfused packed-red-cells were positive for the thick blood film. Plasmodium research in patients was negative 96hours after transfusion, even in the 19 patients who had received parasitized blood units! The home follow-up had permitted to note that 15.78% of blood recipients had developed clinical malaria. Parasitic density ≥240 parasites/mm(3) seems to be a determining factor. Transfusion-transmitted malaria is a reality we ought to consider. Introduction of malaria screening in donated blood qualification testings simultaneously with a framing of the blood donors appear the lasting solution to hope in the future to limit the waited excessive blood evictions.