The role of the Deki Reader™ in malaria diagnosis, treatment and reporting: findings from an Africare pilot project in Nigeria.

BACKGROUND: The Deki Reader is a diagnostic device used with rapid diagnostic tests (RDTs) and linked to an online database for real-time uploads of patient information and results. This is in contrast to visual interpretation of malaria RDTs recorded on the District Health Information System (DHIS). This paper compares records for use of the Deki Reader with DHIS records of visual interpretation of RDTs. RESULTS: A total of 4063 patient encounters/tests were recorded on the Deki Reader database between June 1st and December 31st, 2016. These tests were for 2629 persons who presented with fever and had RDT done. In comparison, data from DHIS 2.0 for same period recorded 7201 persons presenting with fever. 2421 out of the 2629 persons (92.1%), received RDT using Deki Reader compared to 6535 out of 7201 persons (90.4%) recorded on DHIS (p = 0.04). From DHIS records, malaria positivity rate was 51.6% (3375 out of 6535 persons) compared to Deki Reader records of 23.6% (572 out of 2421 persons). The difference between these two rates was significant (p < 0.001). The odds ratio (95% CI) for the association between use of Deki Reader and having a positive malaria result was 0.29 (0.26-0.32). DHIS showed that 4008 persons received Artemisinin-based combination therapy (ACT) while 3989 persons tested positive with RDT or microscopy, compared to 691 out of 705 persons (98.0%) using Deki Reader. Finally, Deki Reader identified 618 processing and manufacturers errors with an error rate of 15.3%. CONCLUSION: The Deki Reader is likely a useful tool for malaria diagnosis, treatment, and real-time data management. It potentially improves diagnostic quality, reduces wastage in ACT administration and improves data quality.

Comparison of visual and automated Deki Reader interpretation of malaria rapid diagnostic tests in rural Tanzanian military health facilities.

BACKGROUND: Although microscopy is a standard diagnostic tool for malaria and the gold standard, it is infrequently used because of unavailability of laboratory facilities and the absence of skilled readers in poor resource settings. Malaria rapid diagnostic tests (RDT) are currently used instead of or as an adjunct to microscopy. However, at very low parasitaemia (usually < 100 asexual parasites/µl), the test line on malaria rapid diagnostic tests can be faint and consequently hard to visualize and this may potentially affect the interpretation of the test results. Fio Corporation (Canada), developed an automated RDT reader named Deki Reader™ for automatic analysis and interpretation of rapid diagnostic tests. This study aimed to compare visual assessment and automated Deki Reader evaluations to interpret malaria rapid diagnostic tests against microscopy. Unlike in the previous studies where expert laboratory technicians interpreted the test results visually and operated the device, in this study low cadre health care workers who have not attended any formal professional training in laboratory sciences were employed. METHODS: Finger prick blood from 1293 outpatients with fever was tested for malaria using RDT and Giemsa-stained microscopy for thick and thin blood smears. Blood samples for RDTs were processed according to manufacturers' instructions automated in the Deki Reader. Results of malaria diagnoses were compared between visual and the automated devise reading of RDT and microscopy. RESULTS: The sensitivity of malaria rapid diagnostic test results interpreted by the Deki Reader was 94.1% and that of visual interpretation was 93.9%. The specificity of malaria rapid diagnostic test results was 71.8% and that of human interpretation was 72.0%. The positive predictive value of malaria RDT results by the Deki Reader and visual interpretation was 75.8 and 75.4%, respectively, while the negative predictive values were 92.8 and 92.4%, respectively. The accuracy of RDT as interpreted by DR and visually was 82.6 and 82.1%, respectively. CONCLUSION: There was no significant difference in performance of RDTs interpreted by either automated DR or visually by unskilled health workers. However, despite the similarities in performance parameters, the device has proven useful because it provides stepwise guidance on processing RDT, data transfer and reporting.

Blood triglyceride levels are associated with DNA methylation at the serine metabolism gene PHGDH.

Efficient interventions to reduce blood triglycerides are few; newer and more tolerable intervention targets are needed. Understanding the molecular mechanisms underlying blood triglyceride levels variation is key to identifying new therapies. To explore the role of epigenetic mechanisms on triglyceride levels, a blood methylome scan was conducted in 199 individuals from 5 French-Canadian families ascertained on venous thromboembolism, and findings were replicated in 324 French unrelated patients with venous thromboembolism. Genetic context and functional relevance were investigated. Two DNA methylation sites associated with triglyceride levels were identified. The first one, located in the ABCG1 gene, was recently reported, whereas the second one, located in the promoter of the PHGDH gene, is novel. The PHGDH methylation site, cg14476101, was found to be associated with variation in triglyceride levels in a threshold manner: cg14476101 was inversely associated with triglyceride levels only when triglyceride levels were above 1.12 mmol/L (discovery P-value = 8.4 × 10-6; replication P-value = 0.0091). Public databases findings supported a functional role of cg14476101 on PHGDH expression. PHGDH catalyses the first step in the serine biosynthesis pathway. These findings highlight the role of epigenetic regulation of the PHGDH gene in triglyceride metabolism, providing novel insights on putative intervention targets.

Sex-specific effect of CPB2 Ala147Thr but not Thr325Ile variants on the risk of venous thrombosis: A comprehensive meta-analysis.

BACKGROUND: Thrombin activatable fibrinolysis inhibitor (TAFI), encoded by the Carboxypeptidase B2 gene (CPB2), is an inhibitor of fibrinolysis and plays a role in the pathogenesis of venous thrombosis. Experimental findings support a functional role of genetic variants in CPB2, while epidemiological studies have been unable to confirm associations with risk of venous thrombosis. Sex-specific effects could underlie the observed inconsistent associations between CPB2 genetic variants and venous thrombosis. METHODS: A comprehensive literature search was conducted for associations between Ala147Thr and Thr325Ile variants with venous thrombosis. Authors were contacted to provide sex-specific genotype counts from their studies. Combined and sex-specific random effects meta-analyses were used to estimate a pooled effect estimate for primary and secondary genetic models. RESULTS: A total of 17 studies met the inclusion criteria. A sex-specific meta-analysis applying a dominant model supported a protective effect of Ala147Thr on venous thrombosis in females (OR = 0.81, 95%CI: 0.68,0.97; p = 0.018), but not in males (OR = 1.06, 95%CI:0.96-1.16; p = 0.263). The Thr325Ile did not show a sex-specific effect but showed variation in allele frequencies by geographic region. A subgroup analysis of studies in European countries showed decreased risk, with a recessive model (OR = 0.83, 95%CI:0.71-0.97, p = 0.021) for venous thrombosis. CONCLUSIONS: A comprehensive literature review, including unpublished data, provided greater statistical power for the analyses and decreased the likelihood of publication bias influencing the results. Sex-specific analyses explained apparent discrepancies across genetic studies of Ala147Thr and venous thrombosis. While, careful selection of genetic models based on population genetics, evolutionary and biological knowledge can increase power by decreasing the need to adjust for testing multiple models.

Leveraging cell type specific regulatory regions to detect SNPs associated with tissue factor pathway inhibitor plasma levels.

Tissue factor pathway inhibitor (TFPI) regulates the formation of intravascular blood clots, which manifest clinically as ischemic heart disease, ischemic stroke, and venous thromboembolism (VTE). TFPI plasma levels are heritable, but the genetics underlying TFPI plasma level variability are poorly understood. Herein we report the first genome-wide association scan (GWAS) of TFPI plasma levels, conducted in 251 individuals from five extended French-Canadian Families ascertained on VTE. To improve discovery, we also applied a hypothesis-driven (HD) GWAS approach that prioritized single nucleotide polymorphisms (SNPs) in (1) hemostasis pathway genes, and (2) vascular endothelial cell (EC) regulatory regions, which are among the highest expressers of TFPI. Our GWAS identified 131 SNPs with suggestive evidence of association (P-value < 5 × 10-8 ), but no SNPs reached the genome-wide threshold for statistical significance. Hemostasis pathway genes were not enriched for TFPI plasma level associated SNPs (global hypothesis test P-value = 0.147), but EC regulatory regions contained more TFPI plasma level associated SNPs than expected by chance (global hypothesis test P-value = 0.046). We therefore stratified our genome-wide SNPs, prioritizing those in EC regulatory regions via stratified false discovery rate (sFDR) control, and reranked the SNPs by q-value. The minimum q-value was 0.27, and the top-ranked SNPs did not show association evidence in the MARTHA replication sample of 1,033 unrelated VTE cases. Although this study did not result in new loci for TFPI, our work lays out a strategy to utilize epigenomic data in prioritization schemes for future GWAS studies.

Preoperative Practice Paired With Instructor Feedback May Not Improve Obstetrics-Gynecology Residents' Operative Performance.

BACKGROUND: There is evidence that preoperative practice prior to surgery can improve trainee performance, but the optimal approach has not been studied. OBJECTIVE: We sought to determine if preoperative practice by surgical trainees paired with instructor feedback improved surgical technique, compared to preoperative practice or feedback alone. METHODS: We conducted a randomized controlled trial of obstetrics-gynecology trainees, stratified on a simulator-assessed surgical skill. Participants were randomized to preoperative practice on a simulator with instructor feedback (PPF), preoperative practice alone (PP), or feedback alone (F). Trainees then completed a laparoscopic salpingectomy, and the operative performance was evaluated using an assessment tool. RESULTS: A total of 18 residents were randomized and completed the study, 6 in each arm. The mean baseline score on the simulator was comparable in each group (67% for PPF, 68% for PP, and 70% for F). While the median score on the assessment tool for laparoscopic salpingectomy in the PPF group was the highest, there was no statistically significant difference in assessment scores for the PPF group (32.75; range, 15-36) compared to the PP group (14.5; range, 10-34) and the F group (21.25; range, 10.5-32). The interrater correlation between the video reviewers was 0.87 (95% confidence interval 0.70-0.95) using the intraclass correlation coefficient. CONCLUSIONS: This study suggests that a surgical preoperative practice with instructor feedback may not improve operative technique compared to either preoperative practice or feedback alone.

Alloimmune Red Blood Cell Antibodies: Prevalence and Pathogenicity in a Canadian Prenatal Population.

OBJECTIVE: The goals of this study were to determine the prevalence and relative frequencies of red blood cell antibodies in a Canadian prenatal population, and to evaluate the fetal and neonatal outcomes of affected pregnancies. METHODS: We conducted a retrospective review of pregnancies that screened positive for red cell antibodies between 2006 and 2010. The following antibodies were included: anti-D, -C, -c, -E, -e, -Fya, -Fyb, -Jka, and-Jkb. Cases of anti-Kell as the sole antibody were excluded. Fetal and neonatal outcome data were then collected and analyzed. RESULTS: The population prevalence of a positive antibody screen was 0.36%. Anti-E was the most frequent antibody at 48.5%, followed by anti-c and anti-Jka. Anti-D made up 6.8% of cases, but had significantly higher titres and was responsible for the majority of severely affected fetuses. Sixteen cases in our series experienced severe adverse fetal or neonatal outcomes. All severe outcomes occurred in cases that had a maximum titre of ≥ 8. CONCLUSION: Despite the decreasing incidence of anti-D alloimmunization, anti-D remains responsible for the majority of severe cases of hemolytic disease of the fetus and newborn.

Objectif : Cette étude avait pour objectif de déterminer la prévalence et la fréquence relative des anticorps anti-érythrocytaires au sein d'une population prénatale canadienne, et d'évaluer les issues fœtales et néonatales des grossesses affectées. Méthodes : Nous avons mené une analyse rétrospective portant sur les grossesses qui ont obtenu des résultats positifs au dépistage des anticorps anti-érythrocytaires entre 2006 et 2010. Les anticorps suivants ont été inclus : anti-D, -C, -c, -E, -e, -Fya, -Fyb, -Jka et -Jkb. Les cas où l'anti-Kell constituait le seul anticorps ont été exclus. Des données sur les issues fœtales et néonatales ont par la suite été recueillies et analysées. Résultats : La prévalence populationnelle de l'obtention d'un résultat positif au dépistage des anticorps a été de 0,36 %. L'anti-E a été l'anticorps le plus fréquent à 48,5 %, suivi de l'anti-c et de l'anti-Jka. Bien que l'anti-D n'ait constitué que 6,8 % des cas, ses titres étaient considérablement accrus et il a été à l'origine de la majorité des cas de fœtus gravement affecté. Dans le cadre de notre série, seize cas ont connu des issues indésirables fœtales ou néonatales graves. Toutes les issues graves ont été constatées dans les cas qui présentaient un titre maximum de ≥ 8. Conclusion : Malgré l'incidence décroissante de l'allo-immunisation anti-D, l'anti-D demeure à l'origine de la majorité des cas graves de maladie hémolytique du fœtus et du nouveau-né.

Recurrence of hidradenitis suppurativa after surgical management: A systematic review and meta-analysis.

BACKGROUND: Hidradenitis suppurativa (HS) is a chronic inflammatory disease of apocrine-bearing skin. Treatment is challenging and long-standing. Surgery is one of the treatment options with varying reported success rates. OBJECTIVE: This study provides a comprehensive systematic review of surgical approaches in the management of HS. METHODS: A systematic literature search and meta-analysis of proportions were performed on the included studies. RESULTS: Of a total of 1147 retrieved articles, 22 were included in the analysis. These were the estimated average recurrences: wide excision, 13.0% (95% confidence interval [CI], 5.0-22.0%); local incision, 22.0% (95% CI, 10.0-37.0%); and deroofing, 27.0% (95% CI, 23.0-31.0%). In the wide excision group, recurrence rates were as follows: 15% (95% CI, 0-72%) for primary closure, 8% (95% CI, 2.0-16.0%) for using flaps, and 6.0% (95% CI, 0.0-24.0%) for grafting. The secondary intention healing option was most commonly chosen after local excision and deroofing. LIMITATIONS: There was poor quality evidence and potential improper reporting of the results. CONCLUSION: This systematic review found lower recurrence rates with wide excision, using skin flaps or skin grafts as the closure methods. The heterogeneity of the patient populations was high and statistically significant within and across all types of excisions.

Genome-wide investigation of DNA methylation marks associated with FV Leiden mutation.

In order to investigate whether DNA methylation marks could contribute to the incomplete penetrance of the FV Leiden mutation, a major genetic risk factor for venous thrombosis (VT), we measured genome-wide DNA methylation levels in peripheral blood samples of 98 VT patients carrying the mutation and 251 VT patients without the mutation using the dedicated Illumina HumanMethylation450 array. The genome-wide analysis of 388,120 CpG probes identified three sites mapping to the SLC19A2 locus whose DNA methylation levels differed significantly (p<3 10-8) between carriers and non-carriers. The three sites replicated (p<2 10-7) in an independent sample of 214 individuals from five large families ascertained on VT and FV Leiden mutation among which 53 were carriers and 161 were non-carriers of the mutation. In both studies, these three CpG sites were also associated (2.33 10-110.05). In conclusion, our work clearly illustrates some promises and pitfalls of DNA methylation investigations on peripheral blood DNA in large epidemiological cohorts. DNA methylation levels at SLC19A2 are influenced by SNPs in LD with FV Leiden, but these DNA methylation marks do not explain the incomplete penetrance of the FV Leiden mutation.

Identification of germline genomic copy number variation in familial pancreatic cancer.

Adenocarcinoma of the pancreas is a significant cause of cancer mortality, and up to 10 % of cases appear to be familial. Heritable genomic copy number variants (CNVs) can modulate gene expression and predispose to disease. Here, we identify candidate predisposition genes for familial pancreatic cancer (FPC) by analyzing germline losses or gains present in one or more high-risk patients and absent in a large control group. A total of 120 FPC cases and 1,194 controls were genotyped on the Affymetrix 500K array, and 36 cases and 2,357 controls were genotyped on the Affymetrix 6.0 array. Detection of CNVs was performed by multiple computational algorithms and partially validated by quantitative PCR. We found no significant difference in the germline CNV profiles of cases and controls. A total of 93 non-redundant FPC-specific CNVs (53 losses and 40 gains) were identified in 50 cases, each CNV present in a single individual. FPC-specific CNVs overlapped the coding region of 88 RefSeq genes. Several of these genes have been reported to be differentially expressed and/or affected by copy number alterations in pancreatic adenocarcinoma. Further investigation in high-risk subjects may elucidate the role of one or more of these genes in genetic predisposition to pancreatic cancer.

A refined, rapid and reproducible high resolution melt (HRM)-based method suitable for quantification of global LINE-1 repetitive element methylation.

BACKGROUND: The methylation of DNA is recognized as a key mechanism in the regulation of genomic stability and evidence for its role in the development of cancer is accumulating. LINE-1 methylation status represents a surrogate measure of genome-wide methylation. FINDINGS: Using high resolution melt (HRM) curve analysis technology, we have established an in-tube assay that is linear (r > 0.9986) with a high amplification efficiency (90-105%), capable of discriminating between partcipant samples with small differences in methylation, and suitable for quantifying a wide range of LINE-1 methylation levels (0-100%)--including the biologically relevant range of 50-90% expected in human DNA. We have optimized this procedure to perform using 2 µg of starting DNA and 2 ng of bisulfite-converted DNA for each PCR reaction. Intra- and inter-assay coefficients of variation were 1.44% and 0.49%, respectively, supporting the high reproducibility and precision of this approach. CONCLUSIONS: In summary, this is a completely linear, quantitative HRM PCR method developed for the measurement of LINE-1 methylation. This cost-efficient, refined and reproducible assay can be performed using minimal amounts of starting DNA. These features make our assay suitable for high throughput analysis of multiple samples from large population-based studies.