Three-dimensional microfluidic devices fabricated in layered paper and tape
Three-dimensional microfluidic devices fabricated in layered paper and tape. antigen9HIV-1 and HIV-2LFIAAntibodies to HIV-1/24LFIAHIV-1 antigen, antibodies to HIV-1/21HIV-1LFIAAntibodies to HIV-14Influenza type ALFIAInfluenza type A antigen4Influenza type BLFIAInfluenza type B antigen4Urinary tract infectionsantigen2AdenovirusLFIAAdenoviral antigen2(Lyme disease)LFIAIgG and IgM antibodies to (syphilis)LFIAAntibodies to spp., spp., and spp.BiochemicalSialidase enzyme activity1 Open in a separate windows aAdapted from reference 10. bNumber of CLIA-waived assessments for each disease/pathogen. cBiochemical assessments measure the production of the products of the enzymatic action. dThere are numerous additional assessments for urinalysis, including assessments for nitrite, pH, protein, leukocytes, etc., that are not included in this table. For details, see Centers for Medicare and Medicaid Services current procedural terminology (CPT) code 81002. Many assessments have received Clinical Laboratory Improvement Amendments (CLIA) waivers that enable POC use (Table 1) (10). CLIA-waived assessments are typically simple and have a low risk Everolimus (RAD001) for an incorrect result. By contrast, assessments that are categorized by the FDA as using a moderate or high Everolimus (RAD001) complexity are typically done at a central laboratory. The categorization criteria include the knowledge needed to perform a test, the needed training and experience, the need for reagent preparation, the number and complexity of operational actions, the extent of calibration and quality control, the equipment maintenance, and the need for impartial interpretation and judgment (11). Not surprisingly, the ability to use LFIA technology at the POC is usually playing an important role in resource-limited countries. In addition, a limited number of POC assessments that utilize molecular approaches have been developed. Several POC assessments that illustrate the range of current applications are described below. Strategic screeningCrAg LFIA for cryptococcal meningitis. The latex Everolimus (RAD001) agglutination assay for the detection of cryptococcal polysaccharide (cryptococcal antigen [CrAg]) was one of the first immunoassays for the diagnosis of infectious disease (12). Recently, an LFIA was developed and FDA-cleared as a prescription-use laboratory assay for the detection of CrAg in serum (13). Although the CrAg LFA is usually a laboratory-based assay in developed countries, a report from the World Health Business (WHO) recently noted that the low cost, rapid results, the lack of required infrastructure, and the ability to be performed by personnel with little training satisfies most of the WHO affordable, sensitive, specific, user-friendly, rapid/strong, equipment-free and deliverable to end users (ASSURED) criteria for POC assessments (14). To this end, Williams et al. recently reported that CrAg lateral flow assay (LFA) testing with fingerstick whole blood in resource-limited settings can facilitate the prioritization of patients on whom to perform a diagnostic lumbar puncture with the measurement of opening pressure (15). An important development in CrAg testing for patients with AIDS was the discovery that screening for CrAg in plasma to detect subclinical disease in patients presenting for antiretroviral treatment (ART) can identify patients at the highest risk for developing cryptococcal meningitis (16). This obtaining led to a WHO recommendation that serum or plasma CrAg screening be considered prior to ART initiation in patients with a CD4 count less than 100 cells/mm3 in those regions with a high prevalence of cryptococcal antigenemia. A positive reaction would trigger preemptive antifungal therapy (14). Ease of sample collectiondetection of HIV antibodies using oral fluids. Several LFIAs have been CLIA waived for the detection of HIV antibodies in fingerstick or venipuncture whole blood (Table 1). In addition, LFIAs for HIV antibodies have been developed for use with oral specimens, e.g., the OraQuick Advance rapid HIV-1/2 antibody test. The test was initially approved by the US Food and Drug Administration in 2004 for professional use with oral fluid, fingerstick whole blood, venipuncture whole blood, and plasma specimens. The test was subsequently approved in 2012 as an over-the-counter test for use with oral fluid specimens. Oral fluids may be more acceptable to patients due to the noninvasive nature of the specimen collection. At-home use also offers an option for individuals who do not wish to be tested in public health settings. Finally, the evaluation of oral fluids reduces blood exposure for health care workers. Despite the many advantages of a rapid HIV test that can be performed by nonprofessionals or by home use, there are also limitations to the use of oral fluids. A systemic review and meta-analysis of the diagnostic accuracy of the test found that the use of the OraQuick test with oral specimens had Rabbit Polyclonal to ALK a pooled sensitivity that was approximately 2% lower than the test’s sensitivity with fingerstick specimens (17). The study of a longitudinal Nigerian cohort using the Avioq HIV-1 Microelisa system found a reduced sensitivity of oral fluid testing for antibody detection compared with that of blood-based testing when specimens Everolimus (RAD001) are obtained early after HIV contamination (18). Curlin et al. also reported that this oral.