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Abstract Background Six species of apicomplexan parasites of the genus Babesia, namely B. microti, B. divergens, B. duncani, B. motasi, B. crassa–like and B. venatorum, are considered to be the primary causal agents of human babesiosis in endemic areas. These six species possess variable degrees of virulence for their primary hosts. Therefore, the accurate identification of these species is critical for the adoption of appropriate therapeutic strategies. Methods We developed a real-time PCR–high-resolution melting (qPCR-HRM) approach targeting 18S ribosomal RNA gene of five Babesia spp. based on melting temperature (T m) and genotype confidence percentage values. This approach was then evaluated using 429 blood samples collected from patients with a history of tick bites, 120 DNA samples mixed with plasmids and 80 laboratory-infected animal samples. Results The sensitivity and specificity of the proposed qPCR-HRM method were 95% and 100%, respectively, and the detection limit was 1–100 copies of the plasmid with the cloned target gene. The detection level depended on the species of Babesia analyzed. The primers designed in this study ensured not only the high interspecific specificity of our proposed method but also a high versatility for different isolates from the same species worldwide. Additionally, the Tm obtained from the prepared plasmid standard is theoretically suitable for identifying isolates of all known sequences of the five Babesia species. Conclusions The developed detection method provides a useful tool for the epidemiological investigation of human babesiosis and pre-transfusion screening. Graphical Abstract

Background: Six species of apicomplexan parasites of the genus Babesia, namely B. microti, B. divergens, B. duncani, B. motasi, B. crassa–like and B. venatorum, are considered to be the primary causal agents of human babesiosis in endemic areas. These six species possess variable degrees of virulence for their primary hosts. Therefore, the accurate identification of these species is critical for the adoption of appropriate therapeutic strategies. Methods: We developed a real-time PCR–high-resolution melting (qPCR-HRM) approach targeting 18S ribosomal RNA gene of five Babesia spp. based on melting temperature (Tm) and genotype confidence percentage values. This approach was then evaluated using 429 blood samples collected from patients with a history of tick bites, 120 DNA samples mixed with plasmids and 80 laboratory-infected animal samples. Results: The sensitivity and specificity of the proposed qPCR-HRM method were 95% and 100%, respectively, and the detection limit was 1–100 copies of the plasmid with the cloned target gene. The detection level depended on the species of Babesia analyzed. The primers designed in this study ensured not only the high interspecific specificity of our proposed method but also a high versatility for different isolates from the same species worldwide. Additionally, the Tm obtained from the prepared plasmid standard is theoretically suitable for identifying isolates of all known sequences of the five Babesia species. Conclusions: The developed detection method provides a useful tool for the epidemiological investigation of human babesiosis and pre-transfusion screening. [ABSTRACT FROM AUTHOR]

Human babesiosis is caused by Babesia duncani that is transmitted through tick bites, blood transfusions, and transplacental transmission. Despite its health burden, diagnostic assays for this pathogen are either unsuitable for clinical applications or have a low detection efficiency; therefore, it remains undetected during transfusion and utilization of blood and blood-component transfusions. This study used a molecular approach via nested quantitative polymerase chain reaction (qPCR) by designing primers and probes corresponding to the variable regions of B. duncani 18S rRNA gene to specifically detect B. duncani DNA in experimentally infected LVG Golden Syrian hamster (n = 70) and human (n = 492; tick bite patients from Gansu Province, China) blood samples. Moreover, comparative analyses of this technique with previously reported nested PCR and microscopy were conducted. The newly optimized diagnostic technique exhibited no cross-reactivity with genomic DNA or plasmids containing the 18S rRNA gene of other zoonotically important Babesia spp., including B. microti, B. divergens, B. crassa, and B. motasi Hebei. The detection limit of nested qPCR was approximately one plasmid copy in 20 μL or one infected red blood cell in 200 μL whole blood. The specificity and sensitivity of the method were 100% and 98.6%, respectively. Comparative analyses revealed that nested qPCR detected B. duncani had relatively higher efficacy and specificity than microscopic examination and nested PCR. The 492 human blood samples were negative for B. duncani infection. Thus, the present study provides an improved diagnostic assay for the efficient and effective detection and analysis of B. duncani infections and its prevalence in infection-prone areas. [ABSTRACT FROM AUTHOR]

Abstract: Babesiosis is a tick- and transfusion-borne disease caused by intraerythrocytic Babesia parasites. In 2009, a 61-year-old Minnesota woman with chronic lymphocytic leukemia and a history of recent chemotherapy and numerous blood transfusions for gastrointestinal bleeding became febrile and anemic 12 days postsplenectomy. Babesia were visualized on blood smears, confirmed by polymerase chain reaction as B. microti. She developed respiratory failure despite initiation of clindamycin and quinine, and required 12 weeks of azithromycin and atovaquone before blood smear and polymerase chain reaction findings were negative. Serologic evidence of B. microti infection was identified in 1 associated blood donor and 1 other recipient of that donor''s blood. Babesia infection can be asymptomatic or cause mild to fulminant disease resulting in multiorgan failure or death. Patients with advanced age, asplenia, or other immune compromise are at risk for severe babesiosis and may require prolonged treatment to eradicate parasitemia. Incidence of transfusion-transmitted babesiosis has increased over the past decade. [Copyright &y& Elsevier]

Complications after pancreaticoduodenal resection occur in at least 30% of patients. Most are a direct result of an intraoperative event, dissection, or anastomoses which account for the most serious morbidities, sepsis, pseudoaneurysms, and hemorrhage. Rarely, complications are due to the systemic impact of the procedure even if the procedure itself was unremarkable. Rare systemic complications after PDR (Transfusion transmitted Babesiosis, pituitary apoplexy, and TRALI) and a number of uncommon and unusual other complications are discussed. Pancreaticoduodenal resection is a significant operation with serious consequences. Decisions on selection of candidates and safe operations should be thoughtful and always in surgeons' minds., (Copyright © 2017 Elsevier Inc. All rights reserved.)