METHODS: We established a multi-country cross-sectional dataset of first available quantitative HCV RNA linked to demographic and clinical data. We excluded individuals on HCV treatment. We analyzed the distribution of HCV RNA and determined critical thresholds for detection of HCV viraemia. We then performed logistic regression to evaluate factors associated with LLV, and derived relative sensitivities for significant covariates.
RESULTS: The dataset included 66,640 individuals with HCV viraemia from Georgia (44.4%), Canada (40.9%), India (8.1%), Cambodia (2.6%), Egypt (1.6%), Pakistan (1.3%), Cameroon (0.4%), Indonesia (0.2%), Thailand (0.2%), Vietnam (0.1%), Malaysia (0.05%), and Mozambique (0.02%). The 97% LOD was 1,318 IU/mL (95% CI 1298.4, 1322.3). Factors associated with LLV were younger age 18-30 vs. 51-64 years (OR 2.56 95% CI 2.19, 2.99), female vs. male sex (OR 1.32, 95% CI 1.18, 1.49), and advanced fibrosis stage F4 vs. F0-1 (OR 1.44, 95%CI 1.21, 1.69). Only the younger age group had a decreased relative sensitivity below 95% at 93.3%.
CONCLUSIONS: In this global dataset, a test with an LOD of 1,318 IU/mL would identify 97% of viraemic HCV infections among almost all populations. This LOD will help guide manufacturers in the development of affordable POC diagnostics to expand HCV testing and linkage to care in LMICs.
LAY SUMMARY: We created and analyzed a dataset from 12 countries with 66,640 participants with chronic hepatitis C virus infection. We determined that about 97% of those with viraemic infection had 1300 International Units/mL or more of circulating virus at the time of diagnosis. While current diagnostic tests can detect as little as 12 International Units/mL of virus, our findings suggest that increasing the level of detection closer to 1300 would maintain good test accuracy and will likely allow for more affordable portable tests to be developed for use in low and middle income countries.
METHODS: This prospective cross-sectional study consecutively recruited 494 patients with suspected dengue from a health clinic in Malaysia. Both RDTs were performed onsite. The evaluated ELISA and reference tests were performed in a virology laboratory. The reference tests comprised of a reverse transcription-polymerase chain reaction and three ELISAs for the detection of dengue NS1 antigen, IgM and IgG antibodies, respectively. The diagnostic performance of evaluated tests was computed using STATA version 12.
RESULTS: The sensitivity and specificity of ViroTrack were 62.3% (95%CI 55.6-68.7) and 95.0% (95%CI 91.7-97.3), versus 66.5% (95%CI 60.0-72.6) and 95.4% (95%CI 92.1-97.6) for SD NS1 ELISA, and 52.4% (95%CI 45.7-59.1) and 97.7% (95%CI 95.1-99.2) for NS1 component of SD Bioline, respectively. The combination of the latter with its IgM and IgG components were able to increase test sensitivity to 82.4% (95%CI 76.8-87.1) with corresponding decrease in specificity to 87.4% (95%CI 82.8-91.2). Although a positive test on any of the NS1 assays would increase the probability of dengue to above 90% in a patient, a negative result would only reduce this probability to 23.0-29.3%. In contrast, this probability of false negative diagnosis would be further reduced to 14.7% (95%CI 11.4-18.6) if SD Bioline NS1/IgM/IgG combo was negative.
CONCLUSIONS: The performance of ViroTrack Dengue Acute was comparable to SD Dengue NS1 Ag ELISA. Addition of serology components to SD Bioline Dengue Duo significantly improved its sensitivity and reduced its false negative rate such that it missed the fewest dengue patients, making it a better point-of-care diagnostic tool. New RDT like ViroTrack Dengue Acute may be a potential alternative to existing RDT if its combination with serology components is proven better in future studies.
MATERIAL AND METHODS: One hundred patients were randomly recruited and then further randomly divided into two groups of 50 patients each. The first group used the POC PCT test along with the standard sepsis parameter monitoring, while the second group had the standard monitoring only (C-reactive protein [CRP] level, total white count, temperature and tracheal aspirate culture). Serial PCT test results and CRP levels were monitored on days 1, 3, 7 and 9. The patients were followed up for 28-day mortality.
RESULTS: Eighty-five patients completed the trial, of whom 43 were in the PCT group and 42 were in the control group. The PCT group had a significantly lower mean (SD) antibiotic treatment duration (10.28 [2.68] days) than the control group (11.52 [3.06]). The mean (SD) difference was -1.25 (95% confidence interval [CI], -2.48 to 0.01; t-statistic [df] = -1.997 [83]; P = 0.049). The PCT group also had a higher number of antibiotic-free days alive during the 28 days after VAP onset than the control group (mean [SD], 10.79 [7.61] vs. 8.72 [6.41]). The Sequential Organ Failure Assessment score was the sole factor for the decrease in duration after VAP onset (regression coefficient β [95% CI], -0.70 [-1.19 to -0.20]; P = 0.006).
CONCLUSIONS: The POC procalcitonin test can reduce the antibiotic treatment duration in patients with VAP.
CASE PRESENTATION: A 23-year-old trauma patient with closed fracture of left femoral shaft and left humerus presented to our emergency department (ED). 11 h after admission to ED, patient became confused, hypoxic and hypotensive. He was then intubated for respiratory failure and mechanically ventilated. Transesophageal ultrasound revealed hyperdynamic heart, dilated right ventricle with no regional wall abnormalities and no major aorta injuries. Whole-body computed tomography was normal. During central venous cannulation of right internal jugular vein (IJV), we found free floating mobile hyperechoic spots, located at the anterior part of the vein. A diagnosis of fat embolism syndrome later was made based on the clinical presentation of long bone fractures and fat globulin in the blood. Despite aggressive fluid resuscitation, patient was a non-responder and needed vasopressor infusion for persistent shock. Blood aspirated during cannulation from the IJV revealed a fat globule. Patient underwent uneventful orthopedic procedures and was discharged well on day 5 of admission.
CONCLUSIONS: Point-of-care ultrasound findings of fat embolism in central vein can facilitate and increase the suspicion of fat embolism syndrome.
FINDINGS: A total of 274 venous blood was collected from normal healthy adults during the community screening programmes. The performance of POC devices, Afinion and Quo-test were compared to central laboratory HPLC method; Adams A1c HA 8160. Both POC devices showed good correlation to HA 8160 with r = 0.94 (p < 0.001) and r = 0.95 (p < 0.001) for Afinion and Quo-test respectively. The means difference were statistically higher between POC and HA 8160 with 0.23% (95% CI 0.19-0.26, p < 0.001) and 0.29% (95% CI 0.24-0.34, p < 0.001) for Afinion and Quo-test respectively.
CONCLUSIONS: Both POC devices could be considered in health clinics for diabetes management but not to be used for the diagnostic purposes.