Displaying publications 1 - 20 of 73 in total

Abstract:
Sort:
  1. Thiha A, Ibrahim F
    Sensors (Basel), 2015;15(5):11431-41.
    PMID: 25993517 DOI: 10.3390/s150511431
    The enzyme-linked Immunosorbent Assay (ELISA) is the gold standard clinical diagnostic tool for the detection and quantification of protein biomarkers. However, conventional ELISA tests have drawbacks in their requirement of time, expensive equipment and expertise for operation. Hence, for the purpose of rapid, high throughput screening and point-of-care diagnosis, researchers are miniaturizing sandwich ELISA procedures on Lab-on-a-Chip and Lab-on-Compact Disc (LOCD) platforms. This paper presents a novel integrated device to detect and interpret the ELISA test results on a LOCD platform. The system applies absorption spectrophotometry to measure the absorbance (optical density) of the sample using a monochromatic light source and optical sensor. The device performs automated analysis of the results and presents absorbance values and diagnostic test results via a graphical display or via Bluetooth to a smartphone platform which also acts as controller of the device. The efficacy of the device was evaluated by performing dengue antibody IgG ELISA on 64 hospitalized patients suspected of dengue. The results demonstrate high accuracy of the device, with 95% sensitivity and 100% specificity in detection when compared with gold standard commercial ELISA microplate readers. This sensor platform represents a significant step towards establishing ELISA as a rapid, inexpensive and automatic testing method for the purpose of point-of-care-testing (POCT) in resource-limited settings.
    Matched MeSH terms: Point-of-Care Systems*
  2. Tan MK, Siddiqi A, Yeo LY
    Sci Rep, 2017 07 27;7(1):6652.
    PMID: 28751783 DOI: 10.1038/s41598-017-07025-x
    The Miniaturised Lab-on-a-Disc (miniLOAD) platform, which utilises surface acoustic waves (SAWs) to drive the rotation of thin millimeter-scale discs on which microchannels can be fabricated and hence microfluidic operations can be performed, offers the possibility of miniaturising its larger counterpart, the Lab-on-a-CD, for true portability in point-of-care applications. A significant limitation of the original miniLOAD concept, however, is that it does not allow for flexible control over the disc rotation direction and speed without manual adjustment of the disc's position, or the use of multiple devices to alter the SAW frequency. In this work, we demonstrate the possibility of achieving such control with the use of tapered interdigitated transducers to confine a SAW beam such that the localised acoustic streaming it generates imparts a force, through hydrodynamic shear, at a specific location on the disc. Varying the torque that arises as a consequence by altering the input frequency to the transducers then allows the rotational velocity and direction of the disc to be controlled with ease. We derive a simple predictive model to illustrate the principle by which this occurs, which we find agrees well with the experimental measurements.
    Matched MeSH terms: Point-of-Care Systems
  3. James V, Kee CY, Ong GY
    J Emerg Med, 2019 Apr;56(4):421-425.
    PMID: 30638645 DOI: 10.1016/j.jemermed.2018.12.015
    BACKGROUND: Point-of-care ultrasonography (POCUS) is increasingly used for both diagnostic and guided procedures. Increasingly, POCUS has been used for identification of pneumonia and to assist in the differentiation of pleural effusions, as well as to guide thoracentesis. As such, there is a need for training with ideally high-fidelity lung ultrasound phantoms to ensure ultrasound proficiency and procedural competency. Unfortunately, most commercial ultrasound phantoms remain expensive and may have limited fidelity.

    OBJECTIVE: Our aim was to create and describe a homemade, high-fidelity ultrasound phantom model for demonstrating pneumonia with pleural effusions for teaching purposes.

    DISCUSSION: An ultrasound phantom was constructed using a water-filled latex glove with a sliver of meat in it, covered over by a palm-sized piece of meat (skin and ribs are optional to increase ultrasonographic details and realism). This would appear like parapneumonic effusions with organized pneumonia under ultrasound examination. Creamer (or talc) can be added to the water in the glove to simulate empyema. The model can also be used to teach simple effusions and for ultrasound-guided thoracentesis and in clinical decision making.

    CONCLUSIONS: Easily prepared, homemade high-fidelity ultrasound phantom models for instructions on identification of pleural effusions and ultrasound-guided pleural tap of parapneumonic effusion were made.

    Matched MeSH terms: Point-of-Care Systems
  4. Balakrishnan SR, Hashim U, Gopinath SC, Poopalan P, Ramayya HR, Iqbal Omar M, et al.
    PLoS One, 2015;10(9):e0137891.
    PMID: 26368287 DOI: 10.1371/journal.pone.0137891
    Human chorionic gonadotropin (hCG), a glycoprotein hormone secreted from the placenta, is a key molecule that indicates pregnancy. Here, we have designed a cost-effective, label-free, in situ point-of-care (POC) immunosensor to estimate hCG using a cuneated 25 nm polysilicon nanogap electrode. A tiny chip with the dimensions of 20.5 × 12.5 mm was fabricated using conventional lithography and size expansion techniques. Furthermore, the sensing surface was functionalized by (3-aminopropyl)triethoxysilane and quantitatively measured the variations in hCG levels from clinically obtained human urine samples. The dielectric properties of the present sensor are shown with a capacitance above 40 nF for samples from pregnant women; it was lower with samples from non-pregnant women. Furthermore, it has been proven that our sensor has a wide linear range of detection, as a sensitivity of 835.88 μA mIU(-1) ml(-2) cm(-2) was attained, and the detection limit was 0.28 mIU/ml (27.78 pg/ml). The dissociation constant Kd of the specific antigen binding to the anti-hCG was calculated as 2.23 ± 0.66 mIU, and the maximum number of binding sites per antigen was Bmax = 22.54 ± 1.46 mIU. The sensing system shown here, with a narrow nanogap, is suitable for high-throughput POC diagnosis, and a single injection can obtain triplicate data or parallel analyses of different targets.
    Matched MeSH terms: Point-of-Care Systems*
  5. Britton S, Cheng Q, Grigg MJ, William T, Anstey NM, McCarthy JS
    Am J Trop Med Hyg, 2016 07 06;95(1):120-2.
    PMID: 27162264 DOI: 10.4269/ajtmh.15-0670
    The simian parasite Plasmodium knowlesi is now the commonest cause of malaria in Malaysia and can rapidly cause severe and fatal malaria. However, microscopic misdiagnosis of Plasmodium species is common, rapid antigen detection tests remain insufficiently sensitive and confirmation of P. knowlesi requires polymerase chain reaction (PCR). Thus available point-of-care diagnostic tests are inadequate. This study reports the development of a simple, sensitive, colorimetric, high-throughput loop-mediated isothermal amplification assay (HtLAMP) diagnostic test using novel primers for the detection of P. knowlesi. This assay is able to detect 0.2 parasites/μL, and compared with PCR has a sensitivity of 96% for the detection of P. knowlesi, making it a potentially field-applicable point-of-care diagnostic tool.
    Matched MeSH terms: Point-of-Care Systems
  6. Lai AKH, Noor Azhar AMB, Bustam AB, Tiong XT, Chan HC, Ahmad RB, et al.
    BMC Med Educ, 2020 Aug 12;20(1):263.
    PMID: 32787921 DOI: 10.1186/s12909-020-02173-7
    BACKGROUND: Although gamification increases user engagement, its effectiveness in point-of-care ultrasonographic training has yet to be fully established. This study was conducted with the primary outcome of evaluating its effectiveness in point-of-care ultrasonographic training as compared to conventional approach.

    METHODS: Participants consisting of junior doctors were randomized into either the (1) gamified or the (2) conventional educational approach for ultrasonographic training.

    RESULTS: A total of 31 junior doctors participated in this study (16 participants in gamified arm, 15 in the conventional arm after one participant from the conventional arm dropped out due to work commitment). Two-way mixed ANOVA test showed that there was no statistically significant interaction between the types of educational approach and time of testing (pre-test, post-test, 2 months post-training) for both theoretical knowledge score and practical skills score, with F(2, 58) = 39.6, p point-of-care ultrasonographic training.

    Matched MeSH terms: Point-of-Care Systems*
  7. Noordin R, Osman E, Kalantari N, Anuar NS, Gorgani-Firouzjaee T, Sithithaworn P, et al.
    Acta Trop, 2022 Feb;226:106251.
    PMID: 34808116 DOI: 10.1016/j.actatropica.2021.106251
    Strongyloides stercoralis is a parasite that causes strongyloidiasis worldwide. It may lead to a life-long infection in immunocompetent people and hyperinfection in immunosuppressed patients. A point-of-care (POC) rapid test is helpful for patient diagnosis in resource-limited settings and as a detection tool in elimination/control programs. Previously, we reported a rapid IgG4 dipstick test (Ss Rapid®) for Strongyloides suitable for a laboratory setting. A POC cassette format of the test, which is field-applicable, has since been developed. Here, we report on a laboratory-based evaluation of the Ss Rapid® cas sette test on 285 sera. We assessed the diagnostic sensitivity of the Ss Rapid® cas sette with 32 sera, comprising samples from larval and/or DNA positive individuals from three countries. Additionally, we also tested samples from 33 seropositive endemic areas residents. We evaluated the diagnostic specificity of the test using 220 samples, comprising sera from other infections (n = 101), allergy cases with high IgE antibodies (n = 4), and blood donors (n = 115). The test showed high diagnostic sensitivity (97%, 31/32), and all sera of the seropositive endemic residents were reactive. It also showed high diagnostic specificity (94.5%, 208/220), and all false-positive samples tested negative after sera adsorption using recombinant NIE-coated microsphere beads. Additionally, we showed that the test worked with spiked whole blood samples. The study results showed that the SsRapid® cas sette test merits further laboratory and field evaluations.
    Matched MeSH terms: Point-of-Care Systems
  8. Warrener L, Slibinskas R, Chua KB, Nigatu W, Brown KE, Sasnauskas K, et al.
    Bull World Health Organ, 2011 Sep 01;89(9):675-82.
    PMID: 21897488 DOI: 10.2471/BLT.11.088427
    OBJECTIVE: To evaluate the performance of a newly developed point-of-care test (POCT) for the detection of measles-specific IgM antibodies in serum and oral fluid specimens and to assess if measles virus nucleic acid could be recovered from used POCT strips.

    METHODS: The POCT was used to test 170 serum specimens collected through measles surveillance or vaccination programmes in Ethiopia, Malaysia and the Russian Federation: 69 were positive for measles immunoglobulin M (IgM) antibodies, 74 were positive for rubella IgM antibodies and 7 were positive for both. Also tested were 282 oral fluid specimens from the measles, mumps and rubella (MMR) surveillance programme of the United Kingdom of Great Britain and Northern Ireland. The Microimmune measles IgM capture enzyme immunoassay was the gold standard for comparison. A panel of 24 oral fluids was used to investigate if measles virus haemagglutinin (H) and nucleocapsid (N) genes could be amplified by polymerase chain reaction directly from used POCT strips.

    FINDINGS: With serum POCT showed a sensitivity and specificity of 90.8% (69/76) and 93.6% (88/94), respectively; with oral fluids, sensitivity and specificity were 90.0% (63/70) and 96.2% (200/208), respectively. Both H and N genes were reliably detected in POCT strips and the N genes could be sequenced for genotyping. Measles virus genes could be recovered from POCT strips after storage for 5 weeks at 20-25 °C.

    CONCLUSION: The POCT has the sensitivity and specificity required of a field-based test for measles diagnosis. However, its role in global measles control programmes requires further evaluation.

    Matched MeSH terms: Point-of-Care Systems/standards*
  9. Sculthorpe-Petley L, Liu C, Hajra SG, Parvar H, Satel J, Trappenberg TP, et al.
    J Neurosci Methods, 2015 Apr 30;245:64-72.
    PMID: 25701685 DOI: 10.1016/j.jneumeth.2015.02.008
    Event-related potentials (ERPs) may provide a non-invasive index of brain function for a range of clinical applications. However, as a lab-based technique, ERPs are limited by technical challenges that prevent full integration into clinical settings.
    Matched MeSH terms: Point-of-Care Systems*
  10. Low KF, Zain ZM, Yean CY
    Biosens Bioelectron, 2017 Jan 15;87:256-263.
    PMID: 27567251 DOI: 10.1016/j.bios.2016.08.064
    A novel enzyme/nanoparticle-based DNA biosensing platform with dual colorimetric/electrochemical approach has been developed for the sequence-specific detection of the bacterium Vibrio cholerae, the causative agent of acute diarrheal disease in cholera. This assay platform exploits the use of shelf-stable and ready-to-use (shelf-ready) reagents to greatly simplify the bioanalysis procedures, allowing the assay platform to be more amenable to point-of-care applications. To assure maximum diagnosis reliability, an internal control (IC) capable of providing instant validation of results was incorporated into the assay. The microbial target, single-stranded DNA amplified with asymmetric PCR, was quantitatively detected via electrochemical stripping analysis of gold nanoparticle-loaded latex microspheres as a signal-amplified hybridization tag, while the incorporated IC was analyzed using a simplified horseradish peroxidase enzyme-based colorimetric scheme by simple visual observation of enzymatic color development. The platform showed excellent diagnostic sensitivity and specificity (100%) when challenged with 145 clinical isolate-spiked fecal specimens. The limits of detection were 0.5ng/ml of genomic DNA and 10 colony-forming units (CFU)/ml of bacterial cells with dynamic ranges of 0-100ng/ml (R(2)=0.992) and log10 (1-10(4) CFU/ml) (R(2)=0.9918), respectively. An accelerated stability test revealed that the assay reagents were stable at temperatures of 4-37°C, with an estimated ambient shelf life of 200 days. The versatility of the biosensing platform makes it easily adaptable for quantitative detection of other microbial pathogens.
    Matched MeSH terms: Point-of-Care Systems
  11. Peyman M, Tai LY, Khaw KW, Ng CM, Win MM, Subrayan V
    Int Ophthalmol, 2015 Oct;35(5):651-5.
    PMID: 25189684 DOI: 10.1007/s10792-014-9989-6
    To assess the intra-observer repeatability and inter-observer reproducibility of central corneal thickness (CCT) measurements of PachPen (Accutome, Inc., Pennsylvania, USA), a hand-held, portable ultrasonic pachymeter when used by an ophthalmic nurse compared to an ophthalmologist. Ophthalmology Clinic, University of Malaya Medical Center In this prospective study, CCT was measured in 184 eyes of 92 healthy subjects, first by a corneal surgeon experienced in ultrasound pachymetry (Observer 1) followed by an ophthalmic nurse new to the procedure (Observer 2). Nine measurements were obtained from each eye by each observer, independently. Measurements were compared between the observers. Coefficients of repeatability and reproducibility were calculated. The Bland-Altman plot was used to assess agreement between observers. Mean age of the study population was 54.3 ± 15.2 years old and consisted of 43.5% male. Mean CCT as measured by Observers 1 and 2 were 528.3 ± 32.9 and 530.7 ± 33.3 µm, respectively. Observer 1 showed higher repeatability of measurements compared to that of Observer 2 (coefficient of repeatability 3.46 vs. 5.55%). The measurements by both observers showed high correlation (0.96) and good agreement (mean difference -2.4 µm; 95% limits of agreement -21.4, 16.7 µm). Coefficient of reproducibility of measurements between observers was 5.08%. Accutome PachPen hand-held ultrasound pachymeters gives excellent intra-observer repeatability and inter-observer reproducibility by personnel of different training grades.
    Matched MeSH terms: Point-of-Care Systems*
  12. Hu J, Wang S, Wang L, Li F, Pingguan-Murphy B, Lu TJ, et al.
    Biosens Bioelectron, 2014 Apr 15;54:585-97.
    PMID: 24333570 DOI: 10.1016/j.bios.2013.10.075
    Advanced diagnostic technologies, such as polymerase chain reaction (PCR) and enzyme-linked immunosorbent assay (ELISA), have been widely used in well-equipped laboratories. However, they are not affordable or accessible in resource-limited settings due to the lack of basic infrastructure and/or trained operators. Paper-based diagnostic technologies are affordable, user-friendly, rapid, robust, and scalable for manufacturing, thus holding great potential to deliver point-of-care (POC) diagnostics to resource-limited settings. In this review, we present the working principles and reaction mechanism of paper-based diagnostics, including dipstick assays, lateral flow assays (LFAs), and microfluidic paper-based analytical devices (μPADs), as well as the selection of substrates and fabrication methods. Further, we report the advances in improving detection sensitivity, quantification readout, procedure simplification and multi-functionalization of paper-based diagnostics, and discuss the disadvantages of paper-based diagnostics. We envision that miniaturized and integrated paper-based diagnostic devices with the sample-in-answer-out capability will meet the diverse requirements for diagnosis and treatment monitoring at the POC.
    Matched MeSH terms: Point-of-Care Systems*
  13. Srijaya TC, Ramasamy TS, Kasim NH
    J Transl Med, 2014;12:243.
    PMID: 25182194 DOI: 10.1186/s12967-014-0243-9
    The inadequacy of existing therapeutic tools together with the paucity of organ donors have always led medical researchers to innovate the current treatment methods or to discover new ways to cure disease. Emergence of cell-based therapies has provided a new framework through which it has given the human world a new hope. Though relatively a new concept, the pace of advancement clearly reveals the significant role that stem cells will ultimately play in the near future. However, there are numerous uncertainties that are prevailing against the present setting of clinical trials related to stem cells: like the best route of cell administration, appropriate dosage, duration and several other applications. A better knowledge of these factors can substantially improve the effectiveness of disease cure or organ repair using this latest therapeutic tool. From a certain perspective, it could be argued that by considering certain proven clinical concepts and experience from synthetic drug system, we could improve the overall efficacy of cell-based therapies. In the past, studies on synthetic drug therapies and their clinical trials have shown that all the aforementioned factors have critical ascendancy over its therapeutic outcomes. Therefore, based on the knowledge gained from synthetic drug delivery systems, we hypothesize that by employing many of the clinical approaches from synthetic drug therapies to this new regenerative therapeutic tool, the efficacy of stem cell-based therapies can also be improved.
    Matched MeSH terms: Point-of-Care Systems/trends*
  14. Choi JR, Hu J, Gong Y, Feng S, Wan Abas WA, Pingguan-Murphy B, et al.
    Analyst, 2016 05 10;141(10):2930-9.
    PMID: 27010033 DOI: 10.1039/c5an02532j
    Lateral flow assays (LFAs) have been extensively explored in nucleic acid testing (NAT) for medical diagnostics, food safety analysis and environmental monitoring. However, the amount of target nucleic acid in a raw sample is usually too low to be directly detected by LFAs, necessitating the process of amplification. Even though cost-effective paper-based amplification techniques have been introduced, they have always been separately performed from LFAs, hence increasing the risk of reagent loss and cross-contaminations. To date, integrating paper-based nucleic acid amplification into colorimetric LFA in a simple, portable and cost-effective manner has not been introduced. Herein, we developed an integrated LFA with the aid of a specially designed handheld battery-powered system for effective amplification and detection of targets in resource-poor settings. Interestingly, using the integrated paper-based loop-mediated isothermal amplification (LAMP)-LFA, we successfully performed highly sensitive and specific target detection, achieving a detection limit of as low as 3 × 10(3) copies of target DNA, which is comparable to the conventional tube-based LAMP-LFA in an unintegrated format. The device may serve in conjunction with a simple paper-based sample preparation to create a fully integrated paper-based sample-to-answer diagnostic device for point-of-care testing (POCT) in the near future.
    Matched MeSH terms: Point-of-Care Systems
  15. Choi JR, Hu J, Tang R, Gong Y, Feng S, Ren H, et al.
    Lab Chip, 2016 Feb 7;16(3):611-21.
    PMID: 26759062 DOI: 10.1039/c5lc01388g
    With advances in point-of-care testing (POCT), lateral flow assays (LFAs) have been explored for nucleic acid detection. However, biological samples generally contain complex compositions and low amounts of target nucleic acids, and currently require laborious off-chip nucleic acid extraction and amplification processes (e.g., tube-based extraction and polymerase chain reaction (PCR)) prior to detection. To the best of our knowledge, even though the integration of DNA extraction and amplification into a paper-based biosensor has been reported, a combination of LFA with the aforementioned steps for simple colorimetric readout has not yet been demonstrated. Here, we demonstrate for the first time an integrated paper-based biosensor incorporating nucleic acid extraction, amplification and visual detection or quantification using a smartphone. A handheld battery-powered heating device was specially developed for nucleic acid amplification in POC settings, which is coupled with this simple assay for rapid target detection. The biosensor can successfully detect Escherichia coli (as a model analyte) in spiked drinking water, milk, blood, and spinach with a detection limit of as low as 10-1000 CFU mL(-1), and Streptococcus pneumonia in clinical blood samples, highlighting its potential use in medical diagnostics, food safety analysis and environmental monitoring. As compared to the lengthy conventional assay, which requires more than 5 hours for the entire sample-to-answer process, it takes about 1 hour for our integrated biosensor. The integrated biosensor holds great potential for detection of various target analytes for wide applications in the near future.
    Matched MeSH terms: Point-of-Care Systems*
  16. Teng CL
    Malays Fam Physician, 2014;9(2):18-25.
    PMID: 25893067 MyJurnal
    This review highlights the high prevalence of antibiotic use for upper respiratory tract infections (URTIs) in a larger part of the Asia-Pacific region. Since URTIs are one of the common reasons for primary care consultations in this region, inappropriate use of antibiotic in both quantity and drug choice has greatly influenced the development of antibiotic resistance. Notwithstanding the paucity of Asia-Pacific data on the above issues, the available information suggests urgent actions needed to be taken to promote judicious antibiotic use at the point-of-care through a multi- pronged approach targeting the patients/consumers (or parents), healthcare providers and health care systems.
    Matched MeSH terms: Point-of-Care Systems
  17. Citartan M
    Talanta, 2021 Sep 01;232:122436.
    PMID: 34074421 DOI: 10.1016/j.talanta.2021.122436
    Dot blot assays have always been associated with antibodies as the main molecular recognition element, which are widely employed in a myriad of diagnostic applications. With the rising of aptamers as the equivalent molecular recognition elements of antibodies, dot blot assays are also one of the diagnostic avenues that should be scrutinized for their amenability with aptamers as the potential surrogates of antibodies. In this review, the stepwise procedures of an aptamer-based dot blot assays are underscored before reviewing the existing aptamer-based dot blot assays developed so far. Most of the applications center on monitoring the progress of SELEX and as the validatory assays to assess the potency of aptamer candidates. For the purpose of diagnostics, the current effort is still languid and as such possible suggestions to galvanize the move to spur the aptamer-based dot blot assays to a point-of-care arena are discussed.
    Matched MeSH terms: Point-of-Care Systems
  18. Low JSY, Thevarajah TM, Chang SW, Goh BT, Khor SM
    Crit Rev Biotechnol, 2020 Dec;40(8):1191-1209.
    PMID: 32811205 DOI: 10.1080/07388551.2020.1808582
    Cardiovascular disease is a major global health issue. In particular, acute myocardial infarction (AMI) requires urgent attention and early diagnosis. The use of point-of-care diagnostics has resulted in the improved management of cardiovascular disease, but a major drawback is that the performance of POC devices does not rival that of central laboratory tests. Recently, many studies and advances have been made in the field of surface-enhanced Raman scattering (SERS), including the development of POC biosensors that utilize this detection method. Here, we present a review of the strengths and limitations of these emerging SERS-based biosensors for AMI diagnosis. The ability of SERS to multiplex sensing against existing POC detection methods are compared and discussed. Furthermore, SERS calibration-free methods that have recently been explored to minimize the inconvenience and eliminate the limitations caused by the limited linear range and interassay differences found in the calibration curves are outlined. In addition, the incorporation of artificial intelligence (AI) in SERS techniques to promote multivariate analysis and enhance diagnostic accuracy are discussed. The future prospects for SERS-based POC devices that include wearable POC SERS devices toward predictive, personalized medicine following the Fourth Industrial Revolution are proposed.
    Matched MeSH terms: Point-of-Care Systems
  19. Teng CL
    MyJurnal
    In the developing world, clinical knowledge management in primary care has a long way to go. Clinical decision support systems, despite its promise to revolutionise healthcare, is slow in its implementation due to the lack of financial investment in information technology. Point-of-care resources, such as comprehensive electronic textbooks delivered via the web or mobile devices, have yet to be fully utilised by the healthcare organisation or individual clinicians. Increasing amount of applicable knowledge of good quality (e.g. clinical practice guidelines and other pre-appraised resources) are now available via the internet. The policy makers and clinicians need to be more informed about the potential benefits and
    limitations of these new tools and resources and make the necessary budgetary provision and learn how best to harness them for patient care.
    Matched MeSH terms: Point-of-Care Systems
  20. Grigg MJ, William T, Barber BE, Parameswaran U, Bird E, Piera K, et al.
    J Clin Microbiol, 2014 Jun;52(6):2053-60.
    PMID: 24696029 DOI: 10.1128/JCM.00181-14
    Plasmodium knowlesi causes severe and fatal malaria in Malaysia. Microscopic misdiagnosis is common and may delay appropriate treatment. P. knowlesi can cross-react with "species-specific" parasite lactate dehydrogenase (pLDH) monoclonal antibodies used in rapid diagnostic tests (RDTs) to detect P. falciparum and P. vivax. At one tertiary-care hospital and two district hospitals in Sabah, we prospectively evaluated two combination RDTs for malaria diagnosis by using both a pan-Plasmodium-pLDH (pan-pLDH)/P. falciparum-specific-pLDH (Pf-pLDH) RDT (OptiMAL-IT) and a non-P. falciparum VOM-pLDH/Pf-HRP2 RDT (CareStart). Differential cross-reactivity among these combinations was hypothesized to differentiate P. knowlesi from other Plasmodium monoinfections. Among 323 patients with PCR-confirmed P. knowlesi (n = 193), P. falciparum (n = 93), and P. vivax (n = 37) monoinfections, the VOM-pLDH individual component had the highest sensitivity for nonsevere (35%; 95% confidence interval [CI], 27 to 43%) and severe (92%; CI, 81 to 100%) P. knowlesi malaria. CareStart demonstrated a P. knowlesi sensitivity of 42% (CI, 34 to 49%) and specificity of 74% (CI, 65 to 82%), a P. vivax sensitivity of 83% (CI, 66 to 93%) and specificity of 71% (CI, 65 to 76%), and a P. falciparum sensitivity of 97% (CI, 90 to 99%) and specificity of 99% (CI, 97 to 100%). OptiMAL-IT demonstrated a P. knowlesi sensitivity of 32% (CI, 25 to 39%) and specificity of 21% (CI, 15 to 29%), a P. vivax sensitivity of 60% (CI, 42 to 75%) and specificity of 97% (CI, 94 to 99%), and a P. falciparum sensitivity of 82% (CI, 72 to 89%) and specificity of 39% (CI, 33 to 46%). The combination of CareStart plus OptiMAL-IT for P. knowlesi using predefined criteria gave a sensitivity of 25% (CI, 19 to 32%) and specificity of 97% (CI, 92 to 99%). Combining two RDT combinations was highly specific for P. knowlesi malaria diagnosis; however, sensitivity was poor. The specificity of pLDH RDTs was decreased for P. vivax and P. falciparum because of P. knowlesi cross-reactivity and cautions against their use alone in areas where P. knowlesi malaria is endemic. Sensitive P. knowlesi-specific RDTs and/or alternative molecular diagnostic tools are needed in areas where P. knowlesi malaria is endemic.
    Matched MeSH terms: Point-of-Care Systems*
Filters
Contact Us

Please provide feedback to Administrator (afdal@afpm.org.my)

External Links