Portable and cost-effective genetic detection and characterization of Plasmodium falciparum hrp2 using the MinION sequencer.

The prevalence of Plasmodium falciparum hrp2 (pfhrp2)-deleted parasites threatens the efficacy of the most used and sensitive malaria rapid diagnostic tests and highlights the need for continued surveillance for this gene deletion. While PCR methods are adequate for determining pfhrp2 presence or absence, they offer a limited view of its genetic diversity. Here, we present a portable sequencing method using the MinION. Pfhrp2 amplicons were generated from individual samples, barcoded, and pooled for sequencing. To overcome potential crosstalk between barcodes, we implemented a coverage-based threshold for pfhrp2 deletion confirmation. Amino acid repeat types were then counted and visualized with custom Python scripts following de novo assembly. We evaluated this assay using well-characterized reference strains and 152 field isolates with and without pfhrp2 deletions, of which 38 were also sequenced on the PacBio platform to provide a standard for comparison. Of 152 field samples, 93 surpassed the positivity threshold, and of those samples, 62/93 had a dominant pfhrp2 repeat type. PacBio-sequenced samples with a dominant repeat-type profile from the MinION sequencing data matched the PacBio profile. This field-deployable assay can be used alone for surveilling pfhrp2 diversity or as a sequencing-based addition to the World Health Organization's existing deletion surveillance protocol.

Recommendations for standardized definitions, clinical assessment, and future research in pediatric clinically unsuspected venous thromboembolism: Communication from the ISTH SSC subcommittee on pediatric and neonatal thrombosis and hemostasis.

Clinically unsuspected venous thromboembolism (VTE) in children is defined as a VTE diagnosed via imaging test performed for surveillance (i.e., with an intent to identify clinically silent VTEs) or incidentally found (most often via imaging performed for evaluation of regional pathology unrelated to VTE) in the absence of any VTE-associated signs or symptoms. Our understanding of the clinical significance of these events in children is limited by a paucity of data on the epidemiology and outcomes of this complication. There is an urgent need for further research in this area to inform optimal management. Recognizing this knowledge gap, this Task Force has previously published a systematic review of the literature in this topic. We now provide guidance recommendations for standardization of definitions and identify future research needs on clinically unsuspected VTE in children. These recommendations will serve to enhance the quantity and quality of evidence on the topic and facilitate the design and execution of cooperative observational studies, and interventional trials of risk-stratified management approaches aimed at preventing and optimizing long-term outcomes of clinically unsuspected VTE in children.

Prevalence, significance, and management of aortic insufficiency in continuous flow left ventricular assist device recipients.

BACKGROUND: Aortic insufficiency (AI) is increasingly recognized as a complication of continuous flow left ventricular assist device support; however, its long-term prevalence, clinical significance, and efficacy of potential interventions are not well known. METHODS AND RESULTS: We studied the prevalence and management of AI in 232 patients with continuous flow left ventricular assist device at our institution. Patients with aortic valve (AV) surgery before left ventricular assist device implantation were excluded from analysis. To examine the prevalence of de novo AI, patients without preoperative AI were divided into a retrospective and a prospective cohort based on whether a dedicated speed optimization study had been performed at the time of discharge. Forty-three patients underwent AV repair at the time of implant, and 3 subsequently developed greater than mild AI. In patients without surgical AV manipulation and no AI at the time of implant, Kaplan-Meier analysis revealed that freedom from greater than mild de novo AI at 1 year was 77.6±4.2%, and that at least moderate AI is expected to develop in 37.6±13.3% after 3 years. Nonopening of the AV was strongly associated with de novo AI development in patients without prospective discharge speed optimization. Seven of 21 patients with at least moderate AI developed symptomatic heart failure requiring surgical intervention. CONCLUSIONS: AI is common in patients with continuous flow left ventricular assist devices and may lead to clinical decompensation requiring surgical correction. The prevalence of AI is substantially less in patients whose AV opens, and optimized loading conditions may reduce AI prevalence in those patients in whom AV opening cannot be achieved.

Quality of life assessment in children commencing home INR self-testing.

INTRODUCTION: Management of oral anticoagulant therapy (OAT) in children is complex and frequent testing of the International Normalised Ratio (INR) is a significant burden. This study evaluates the impact of a home INR self-testing (home ST) program on the quality of life (QoL) of children and their families. The aim of the study was to determine if participation in a home ST program improves QoL for children requiring long-term OAT and their families. MATERIALS AND METHODS: Children aged eight to 18 years requiring long-term OAT and parents of children participated. Quantitative methods comprised three validated QoL questionnaires; the anticoagulation specific PAC QL©, the PedsQL™ and the PedsQL FIM™. Questionnaires were completed before commencing home ST and 6-12 months later. Qualitative methods consisted of open-ended questions which participants answered when completing the questionnaires for the second time. Results of INRs tested at home were collected. RESULTS: Fifty-five parents and 35 children participated. The percentage of time the children's INRs were in their target therapeutic range was 71.3. Parents reported statistically significant improvements in QoL for themselves (mean increase 6.9), their family (mean increase 8.6) and their child (mean increase 11.1) following the commencement of home ST (difference p≤0.003 on all questionnaires). The children did not report a statically significant improvement in QoL. CONCLUSION: Parents reported significant improvement for their child's QoL, their QoL and the families' function following commencement of home ST. Children did not report a significant improvement in their QoL, but clearly identified satisfaction with home ST.

The economic costs of routine INR monitoring in infants and children--examining point-of-care devices used within the home setting compared to traditional anticoagulation clinic monitoring.

INTRODUCTION: The use of point-of-care (POC) devices within the home for routine INR monitoring has demonstrated reliability, safety and effectiveness in the management of infants and children requiring long-term warfarin therapy. However, a comprehensive cost-analysis of using this method of management, compared to attending anticoagulation clinics has not been reported. The aim of this study was to compare the estimated societal costs of attending anticoagulation clinics for routine INR monitoring to using a POC test in the home. MATERIALS AND METHODS: This study used a comparative before-and-after design that included 60 infants and children managed via the Haematology department at a tertiary paediatric centre. Each participant was exposed to both modes of management at various times for a period of ≥3 months. A questionnaire, consisting of 25 questions was sent to families to complete and return. Data collected included: the frequency of monitoring, mode of travel to and from clinics, total time consumed, and primary carer's income level. RESULTS: The home monitoring cohort saved a total of 1 hour 19 minutes per INR test compared to attending anticoagulation clinics and had a cost saving to society of $66.83 (AUD) per INR test compared to traditional care; incorporating health sector costs, travel expenses and lost time. CONCLUSIONS: The traditional model of care requires a considerable investment of time per test from both child and carer. Home INR monitoring in infants and children provides greater societal economic benefits compared to traditional models.

Filter paper collection of Plasmodium falciparum mRNA for detecting low-density gametocytes.

BACKGROUND: Accurate sampling of sub-microscopic gametocytes is necessary for epidemiological studies to identify the infectious reservoir of Plasmodium falciparum. Detection of gametocyte mRNA achieves sensitive detection, but requires careful handling of samples. Filter papers can be used for collecting RNA samples, but rigorous testing of their capacity to withstand adverse storage conditions has not been fully explored. METHODS: Three gametocyte dilutions: 10/µL, 1.0/µL and 0.1/µL were spotted onto Whatman™ 903 Protein Saver Cards, FTA Classic Cards and 3MM filter papers that were stored under frozen, cold chain or tropical conditions for up to 13 weeks . RNA was extracted, then detected by quantitative nucleic acid sequence-based amplification (QT-NASBA) and reverse-transcriptase PCR (RT-PCR). RESULTS: Successful gametocyte detection was more frequently observed from the Whatman 903 Protein Saver Card compared to the Whatman FTA Classic Card, by both techniques (p<0.0001). When papers were stored at higher temperatures, a loss in sensitivity was experienced for the FTA Classic Card but not the 903 Protein Saver Card or Whatman 3MM filter paper. The sensitivity of gametocyte detection was decreased when papers were stored at high humidity. CONCLUSIONS: This study indicates the Whatman 903 Protein Saver Card is better for Pfs25 mRNA sampling compared to the Whatman FTA Classic Card, and that the Whatman 3MM filter paper may prove to be a satisfactory cheaper option for Pfs25 mRNA sampling. When appropriately dried, filter papers provide a useful approach to Pfs25 mRNA sampling, especially in settings where storage in RNA-protecting buffer is not possible.

HEEADSSS assessment for adolescents requiring anticoagulation therapy.

The care of adolescents with complex chronic illness needs to be developmentally appropriate to encourage adherence, knowledge retention and self-management. There has been an increase in the number of adolescents requiring long-term or lifelong anticoagulation therapy, related to either an underlying illness or idiopathic deep vein thrombosis. The burden of anticoagulant therapy, the associated risks and the required lifestyle changes can significantly impact on psychosocial well-being in the adolescent patient. This review identifies issues pertinent to adolescent anticoagulation management and discusses strategies to support optimal management. The HEEADSSS (Home, Education and employment, Eating, Activities with peers, Drugs, Sexual activity, Suicide and depression, and Safety) framework was used to provide guidance in undertaking a psychosocial assessment of adolescents requiring anticoagulant therapy in conjunction with a structured education strategy. Adolescent anticoagulant management strategies employing developmentally appropriate assessment and education will likely result in improved therapeutic outcomes for the patient and potentially facilitate transition to adult-based care.

Telemedicine in wound healing.

Better care for patients and improved health care depends on the availability of good information which is accessible when and where it is needed. The development of technology, more specifically the Internet, has expanded the means whereby information can be acquired and transmitted over large distances enabling the concept of telemedicine to become a reality. Telemedicine, defined as the practise of medicine at a distance, encompasses diagnosis, education and treatment. It is a technology that many thought would expand rapidly and change the face of medicine. However, this has not happened and during the last decade although certain telemedicine applications, such as video-consulting and teleradiology, have matured to become essential health care services in some countries, others, such as telepathology, remain the subject of intensive research effort. Telemedicine can be used in almost any medical specialty although the specialties best suited are those with a high visual component. Wound healing and wound management is thus a prime candidate for telemedicine. Development of a suitable telemedical system in this field could have a significant effect on wound care in the community, tertiary referral patterns and hospital admission rates.