Displaying publications 1 - 20 of 123 in total

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  1. Zaw MT, Lin Z
    J Microbiol Immunol Infect, 2019 Oct;52(5):679-684.
    PMID: 31320238 DOI: 10.1016/j.jmii.2019.05.012
    Plasmodium knowlesi is now regarded as the fifth malaria parasite causing human malaria as it is widely distributed in South-East Asian countries especially east Malaysia where two Malaysian states namely Sabah and Sarawak are situated. In 2004, Polymerase Chain Reaction (PCR) was applied for diagnosing knowlesi malaria in the Kapit Division of Sarawak, Malaysia, so that human P. knowlesi infections could be detected correctly while blood film microscopy diagnosed incorrectly as Plasmodium malariae. This parasite is transmitted from simian hosts to humans via Anopheles vectors. Indonesia is the another country in South East Asia where knowlesi malaria is moderately prevalent. In the last decade, Sarawak and Sabah, the two states of east Malaysia became the target of P. knowlesi research due to prevalence of cases with occasional fatal infections. The host species of P. knowlesi are three macaque species namely Macaca fascicularis, Macaca nemestrina and Macaca leonina while the vector species are the Leucosphyrus Complex and the Dirus Complex of the Leucophyrus Group of Anopheles mosquitoes. Rapid diagnostic tests (RDT) are non-existent for knowlesi malaria although timely treatment is necessary for preventing complications, fatality and drug resistance. Development of RDT is essential in dealing with P. knowlesi infections in poor rural healthcare services. Genetic studies of the parasite on possibility of human-to-human transmission of P. knowlesi were recommended for further studies.
    Matched MeSH terms: Diagnostic Tests, Routine
  2. Zaini S, Manivanna Bharathy HA, Sulaiman AH, Singh Gill J, Ong Hui K, Zaman Huri H, et al.
    PMID: 29970848 DOI: 10.3390/ijerph15071402
    Shared decision-making (SDM) has been recognized as an important tool in the mental health field and considered as a crucial component of patient-centered care. Therefore, the purpose of this study was to develop a strategic tool towards the promotion and implementation of SDM in the use of antidepressants among patients with major depressive disorder. Nineteen doctors and 11 major depressive disorder patients who are involved in psychiatric outpatient clinic appointments were purposively selected and recruited to participate in one of six focus groups in a large teaching hospital in Malaysia. Focus groups were transcribed verbatim and analyzed using a thematic approach to identify current views on providing information needed for SDM practice towards its implementation in near future. Patients’ and doctors’ views were organized into six major themes, which are; summary of treatment options, correct ways of taking medication, potential side effects of treatments related to patients, sharing of case study related to the treatment options, cost of treatment options, and input from pharmacist. The information may be included in the SDM tool which can be useful to inform further research efforts and developments that contribute towards the successful implementation of SDM into clinical practice.

    Study site: University Malaya Medical Centre (UMMC)
    Matched MeSH terms: Diagnostic Tests, Routine
  3. Zafarina Z, Panneerchelvam S
    Malays J Med Sci, 2009 Jul;16(3):35-40.
    PMID: 22589663 MyJurnal
    An unidentified animal species named the Jenglot and claimed to be a rare living animal species was recently found in the deep jungle of Irian Jaya, Indonesia; brought to Kuala Lumpur, Malaysia by a businessman; and exhibited in a local museum. The owner of the Jenglot carcasses had made a request to perform DNA analysis on the Jenglot to ascertain its species.
    Matched MeSH terms: Diagnostic Tests, Routine
  4. Yusof MYPM, Rahman NLA, Asri AAA, Othman NI, Wan Mokhtar I
    Imaging Sci Dent, 2017 Dec;47(4):233-239.
    PMID: 29279822 DOI: 10.5624/isd.2017.47.4.233
    Purpose: This study was performed to quantify the repeat rate of imaging acquisitions based on different clinical examinations, and to assess the prevalence of error types in intraoral bitewing and periapical imaging using a digital complementary metal-oxide-semiconductor (CMOS) intraoral sensor.

    Materials and Methods: A total of 8,030 intraoral images were retrospectively collected from 3 groups of undergraduate clinical dental students. The type of examination, stage of the procedure, and reasons for repetition were analysed and recorded. The repeat rate was calculated as the total number of repeated images divided by the total number of examinations. The weighted Cohen's kappa for inter- and intra-observer agreement was used after calibration and prior to image analysis.

    Results: The overall repeat rate on intraoral periapical images was 34.4%. A total of 1,978 repeated periapical images were from endodontic assessment, which included working length estimation (WLE), trial gutta-percha (tGP), obturation, and removal of gutta-percha (rGP). In the endodontic imaging, the highest repeat rate was from WLE (51.9%) followed by tGP (48.5%), obturation (42.2%), and rGP (35.6%). In bitewing images, the repeat rate was 15.1% and poor angulation was identified as the most common cause of error. A substantial level of intra- and interobserver agreement was achieved.

    Conclusion: The repeat rates in this study were relatively high, especially for certain clinical procedures, warranting training in optimization techniques and radiation protection. Repeat analysis should be performed from time to time to enhance quality assurance and hence deliver high-quality health services to patients.

    Matched MeSH terms: Diagnostic Tests, Routine
  5. Yu CY, Chan KG, Yean CY, Ang GY
    Diagnostics (Basel), 2021 Jan 01;11(1).
    PMID: 33401392 DOI: 10.3390/diagnostics11010053
    The coronavirus disease 2019 (COVID-19) caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) began as a cluster of pneumonia cases in Wuhan, China before spreading to over 200 countries and territories on six continents in less than six months. Despite rigorous global containment and quarantine efforts to limit the transmission of the virus, COVID-19 cases and deaths have continued to increase, leaving devastating impacts on the lives of many with far-reaching effects on the global society, economy and healthcare system. With over 43 million cases and 1.1 million deaths recorded worldwide, accurate and rapid diagnosis continues to be a cornerstone of pandemic control. In this review, we aim to present an objective overview of the latest nucleic acid-based diagnostic tests for the detection of SARS-CoV-2 that have been authorized by the Food and Drug Administration (FDA) under emergency use authorization (EUA) as of 31 October 2020. We systematically summarize and compare the principles, technologies, protocols and performance characteristics of amplification- and sequencing-based tests that have become alternatives to the CDC 2019-nCoV Real-Time RT-PCR Diagnostic Panel. We highlight the notable features of the tests including authorized settings, along with the advantages and disadvantages of the tests. We conclude with a brief discussion on the current challenges and future perspectives of COVID-19 diagnostics.
    Matched MeSH terms: Diagnostic Tests, Routine
  6. Yakubu Y, Ong BL, Zakaria Z, Hassan L, Mutalib AR, Ngeow YF, et al.
    Prev Vet Med, 2016 Mar 1;125:147-53.
    PMID: 26775804 DOI: 10.1016/j.prevetmed.2016.01.008
    Elephant tuberculosis (TB) caused by Mycobacterium tuberculosis is an important re-emerging zoonosis with considerable conservation and public health risk. We conducted prospective cohort and cross-sectional studies in elephants and wildlife staff respectively in order to identify potential risk factors associated with TB in captive Asian elephants and their handlers in Peninsular Malaysia. Sixty elephants in six different facilities were screened for TB longitudinally using the ElephantTB STAT-PAK and DPP VetTB assays from February 2012 to May 2014, and 149 wildlife staff were examined for tuberculosis infection using the QuantiFERON-TB Gold In-tube (QFT) assay from January to April, 2012. Information on potential risk factors associated with infection in both elephants and staff were collected using questionnaires and facility records. The overall seroprevalence of TB amongst the elephants was 23.3% (95% CI: 13.8-36.3) and the risk of seroconversion was significantly higher among elephants with assigned mahouts [p=0.022, OR=4.9 (95% CI: 1.3-18.2)]. The percentage of QFT responders among wildlife staff was 24.8% (95% CI: 18.3-32.7) and the risk of infection was observed to be significantly associated with being a zoo employee [p=0.018, OR=2.7 (95% CI: 1.2-6.3)] or elephant handler [p=0.035, OR=4.1 (95% CI: 1.1-15.5)]. These findings revealed a potential risk of TB infection in captive elephants and handlers in Malaysia, and emphasize the need for TB screening of newly acquired elephants, isolating sero-positive elephants and performing further diagnostic tests to determine their infection status, and screening elephant handlers for TB, pre- and post-employment.
    Matched MeSH terms: Diagnostic Tests, Routine
  7. Yaakob Y, Rodrigues KF, Opook F, William T, John DV
    Malays J Med Sci, 2017 Oct;24(5):44-51.
    PMID: 29386971 DOI: 10.21315/mjms2017.24.5.5
    Background: Synthetic biology is emerging as a viable alternative for the production of recombinant antigens for diagnostic applications. It offers a safe alternative for the synthesis of antigenic principles derived from organisms that pose a high biological risk.

    Methods: Here, we describe an enzyme-linked immunosorbent assay (ELISA) using the synthetic recombinant LipL32 (rLipL32) protein expressed in Escherichia coli for the detection of Leptospira-specific antibodies in human serum samples. The rLipL32-based ELISA was compared with a microscopic agglutination test (MAT), which is currently used as the gold standard for the diagnosis of leptospirosis.

    Results: Our results showed that all the MAT-positive serum samples were positive for Leptospira-specific IgG in an ELISA, while 65% (n = 13) of these samples were also positive for Leptospira-specific IgM. In the MAT-negative serum samples, 80% and 55% of the samples were detected as negative by an ELISA for Leptospira-specific IgM and IgG, respectively.

    Conclusion: An ELISA using the synthetic rLipL32 antigen was able to distinguish Leptospira-specific IgM (sensitivity 65% and specificity 80%) and IgG (sensitivity 100% and specificity 55%) in human serum samples and has the potential to serve as a rapid diagnostic test for leptospirosis.

    Matched MeSH terms: Diagnostic Tests, Routine
  8. Xu S, Xue Y, Guo F, Xu M, Gopinath SCB, Mao X
    3 Biotech, 2020 May;10(5):227.
    PMID: 32373419 DOI: 10.1007/s13205-020-02216-2
    Herein, a rapid and sensitive current-volt measurement was developed for identifying the IS6110 DNA sequence to diagnose Mycobacterium tuberculosis (TB). An aminated capture probe was immobilized on a 1,1'-carbonyldiimidazole-functionalized interdigitated electrode (IDE) silica substrate, and the target sequence was detected by complementation. It was found that all tested concentrations displayed a higher response in current changes than the control, and the limit of detection was 10 fM. The sensitivity ranged from 1 to 10 fM. The control sequences with single-, triple-mismatch and noncomplementary sequences showed great discrimination. This rapid and easy DNA detection method helps to identify M. tuberculosis for early-stage diagnosis of TB.
    Matched MeSH terms: Diagnostic Tests, Routine
  9. Wong WCW, Lo YR, Jiang S, Peng M, Zhu S, Kidd MR, et al.
    Fam Pract, 2018 12 12;35(6):731-737.
    PMID: 29741661 DOI: 10.1093/fampra/cmy032
    Objective: The study aimed to decentralize hepatitis testing and management services to primary care in China.

    Methods: A nationwide representative provider survey amongst community health centres (CHCs) using randomized stratified sampling methods was conducted between September and December 2015. One hundred and eighty CHCs and frontline primary care practitioners from 20 cities across three administrative regions of Western, Central and Eastern China were invited to participate.

    Results: One hundred and forty-nine clinicians-in-charge (79%), 1734 doctors and 1846 nurses participated (86%). Majority of CHCs (80%, 95% CI: 74-87) offered hepatitis B testing, but just over half (55%, 95% CI: 46-65) offered hepatitis C testing. The majority of doctors (87%) and nurses (85%) felt that there were benefits for providing hepatitis testing at CHCs. The major barriers for not offering hepatitis testing were lack of training (54%) and financial support (23%). Multivariate analysis showed that the major determinants for CHCs to offer hepatitis B and C testing were the number of nurses (AOR 1.1) and written policies for hepatitis B diagnosis (AOR 12.7-27.1), and for hepatitis B the availability of reproductive health service.

    Conclusions: Primary care providers in China could play a pivotal role in screening, diagnosing and treating millions of people with chronic hepatitis B and C in China.

    Matched MeSH terms: Diagnostic Tests, Routine/methods*
  10. Wong PF, Wong LP, AbuBakar S
    J Infect Public Health, 2020 Feb;13(2):193-198.
    PMID: 31405788 DOI: 10.1016/j.jiph.2019.07.012
    BACKGROUND: Delayed diagnosis of dengue cases with increased risk for severe disease could lead to poor disease outcome. To date there is no specific laboratory diagnostic test for severe dengue. This qualitative study explored expert views regarding current issues in diagnosing severe dengue, rationale for severe dengue-specific diagnostics, future prospects and features of potential diagnostics for severe dengue.

    METHODS: In-depth individual interviews with thematic saturation were conducted between May and July 2018. The data was analyzed using thematic analysis.

    RESULTS: Based on expert opinion, diagnosis of severe dengue is challenging as it depends on astute clinical interpretation of non-dengue-specific clinical and laboratory findings. A specific test that detects impending manifestation of severe dengue could 1) overcome failure in identifying severe disease for referral or admission, 2) facilitate timely and appropriate management of plasma leakage and bleeding, 3) overcome the lack of clinical expertise and laboratory diagnosis in rural health settings. The most important feature of any diagnostics for severe dengue is the point-of-care (POC) format where it can be performed at or near the bedside.

    CONCLUSION: The development of diagnostics to detect impending severe dengue is warranted to reduce the morbidity and mortality rates of dengue infection and it should be prioritized.

    Matched MeSH terms: Diagnostic Tests, Routine/methods
  11. Wong CL, Yong CY, Ong HK, Ho KL, Tan WS
    Front Vet Sci, 2020;7:477.
    PMID: 32974392 DOI: 10.3389/fvets.2020.00477
    Foot-and-mouth disease (FMD) is a devastating livestock disease caused by foot-and-mouth disease virus (FMDV). Outbreaks of this disease in a country always result in conspicuous economic losses to livestock industry and subsequently lead to serious socioeconomic damages due to the immediate imposition of trade embargo. Rapid and accurate diagnoses are imperative to control this infectious virus. In the current review, enzyme-linked immunosorbent assay (ELISA)-based methods used in FMD diagnosis are extensively reviewed, particularly the sandwich, liquid-phase blocking, and solid-phase competition ELISA. The differentiation of infected animals from vaccinated animals using ELISA-based methods is also highlighted, in which the role of 3ABC polyprotein as a marker is reviewed intensively. Recently, more studies are focusing on the molecular diagnostic methods, which detect the viral nucleic acids based on reverse transcription-polymerase chain reaction (RT-PCR) and RT-loop-mediated isothermal amplification (RT-LAMP). These methods are generally more sensitive because of their ability to amplify a minute amount of the viral nucleic acids. In this digital era, the RT-PCR and RT-LAMP are progressing toward the mobile versions, aiming for on-site FMDV diagnosis. Apart from RT-PCR and RT-LAMP, another diagnostic assay specifically designed for on-site diagnosis is the lateral flow immunochromatographic test strips. These test strips have some distinct advantages over other diagnostic methods, whereby the assay often does not require the aid of an external device, which greatly lowers the cost per test. In addition, the on-site diagnostic test can be easily performed by untrained personnel including farmers, and the results can be obtained in a few minutes. Lastly, the use of FMDV diagnostic assays for progressive control of the disease is also discussed critically.
    Matched MeSH terms: Diagnostic Tests, Routine
  12. Won KY, Gass K, Biamonte M, Dagne DA, Ducker C, Hanna C, et al.
    PLoS Negl Trop Dis, 2021 11;15(11):e0009968.
    PMID: 34780503 DOI: 10.1371/journal.pntd.0009968
    As lymphatic filariasis (LF) programs move closer to established targets for validation elimination of LF as a public health problem, diagnostic tools capable of supporting the needs of the programs are critical for success. Known limitations of existing diagnostic tools make it challenging to have confidence that program endpoints have been achieved. In 2019, the World Health Organization (WHO) established a Diagnostic Technical Advisory Group (DTAG) for Neglected Tropical Diseases tasked with prioritizing diagnostic needs including defining use-cases and target product profiles (TPPs) for needed tools. Subsequently, disease-specific DTAG subgroups, including one focused on LF, were established to develop TPPs and use-case analyses to be used by product developers. Here, we describe the development of two priority TPPs for LF diagnostics needed for making decisions for stopping mass drug administration (MDA) of a triple drug regimen and surveillance. Utilizing the WHO core TPP development process as the framework, the LF subgroup convened to discuss and determine attributes required for each use case. TPPs considered the following parameters: product use, design, performance, product configuration and cost, and access and equity. Version 1.0 TPPs for two use cases were published by WHO on 12 March 2021 within the WHO Global Observatory on Health Research and Development. A common TPP characteristic that emerged in both use cases was the need to identify new biomarkers that would allow for greater precision in program delivery. As LF diagnostic tests are rarely used for individual clinical diagnosis, it became apparent that reliance on population-based surveys for decision making requires consideration of test performance in the context of such surveys. In low prevalence settings, the number of false positive test results may lead to unnecessary continuation or resumption of MDA, thus wasting valuable resources and time. Therefore, highly specific diagnostic tools are paramount when used to measure low thresholds. The TPP process brought to the forefront the importance of linking use case, program platform and diagnostic performance characteristics when defining required criteria for diagnostic tools.
    Matched MeSH terms: Diagnostic Tests, Routine/methods; Diagnostic Tests, Routine/standards*
  13. Vola A, Tamarozzi F, Noordin R, Yunus MH, Khanbabaie S, De Silvestri A, et al.
    Diagn Microbiol Infect Dis, 2018 Sep;92(1):31-33.
    PMID: 29776711 DOI: 10.1016/j.diagmicrobio.2018.04.007
    Rapid diagnostic tests for cystic echinococcosis (CE) are convenient to support ultrasound diagnosis in uncertain cases, especially in resource-limited settings. We found comparable diagnostic performances of the experimental Hyd Rapid Test and the commercial VIRapid HYDATIDOSIS Test, used in our diagnostic laboratory, using samples from well-characterized hepatic CE cases.
    Matched MeSH terms: Diagnostic Tests, Routine/methods*
  14. Umi Nadrah Amran, Nur Nadiah Mohd Rais
    MyJurnal
    In medical imaging practice, the act of removing any clothes from the region of interest is justified as to prevent the presence of artefacts on radiographs. However, by doing so, the ‘aurah’ of the patients, especially for the Muslims, are not observed and can be considered as violating their privacy if they are not well-informed beforehand. Previous studies have proved that radiographs with the presence of some fabric materials on the region of interest are radiographically acceptable. Therefore, the aims of this study are to tackle the issue of exposing one’s ‘aurah’ for a knee x-ray examination to take place and also to add insufficiency from the previous studies.
    Matched MeSH terms: Diagnostic Tests, Routine
  15. Tsai MH, Chan CK, Chang YC, Lin CH, Liou CW, Chang WN, et al.
    Front Neurol, 2018;9:515.
    PMID: 30034362 DOI: 10.3389/fneur.2018.00515
    Objective: Focal epilepsy is the most common subtype of epilepsies in which the influence of underlying genetic factors is emerging but remains largely uncharacterized. The purpose of this study is to determine the contribution of currently known disease-causing genes in a large cohort (n = 593) of common focal non-lesional epilepsy patients. Methods: The customized focal epilepsy gene panel (21 genes) was based on multiplex polymerase chain reaction (PCR) and sequenced by Illumina MiSeq platform. Results: Eleven variants (1.85%) were considered as pathogenic or likely pathogenic, including seven novel mutations. There were three SCN1A (p.Leu890Pro, p.Arg1636Ter, and p.Met1714Val), three PRRT2 (two p.Arg217Profs*8 and p.Leu298Pro), two CHRNA4 (p.Ser284Leu, p.Ile321Asn), one DEPDC5 (p.Val516Ter), one PCDH19 (p.Asp233Asn), and one SLC2A1 (p.Ser414Ter) variants. Additionally, 16 other rare variants were classified as unknown significance due to inconsistent phenotype or lack of segregation data. Conclusion: Currently known focal epilepsy genes only explained a very small subset of focal epilepsy patients. This indicates that the underlying genetic architecture of focal epilepsies is very heterogeneous and more novel genes are likely to be discovered. Our study highlights the usefulness, challenges and limitations of using the multi-gene panel as a diagnostic test in routine clinical practice in patients with focal epilepsy.
    Matched MeSH terms: Diagnostic Tests, Routine
  16. Thriemer K, Ley B, Bobogare A, Dysoley L, Alam MS, Pasaribu AP, et al.
    Malar J, 2017 04 05;16(1):141.
    PMID: 28381261 DOI: 10.1186/s12936-017-1784-1
    The delivery of safe and effective radical cure for Plasmodium vivax is one of the greatest challenges for achieving malaria elimination from the Asia-Pacific by 2030. During the annual meeting of the Asia Pacific Malaria Elimination Network Vivax Working Group in October 2016, a round table discussion was held to discuss the programmatic issues hindering the widespread use of primaquine (PQ) radical cure. Participants included 73 representatives from 16 partner countries and 33 institutional partners and other research institutes. In this meeting report, the key discussion points are presented and grouped into five themes: (i) current barriers for glucose-6-phosphate deficiency (G6PD) testing prior to PQ radical cure, (ii) necessary properties of G6PD tests for wide scale deployment, (iii) the promotion of G6PD testing, (iv) improving adherence to PQ regimens and (v) the challenges for future tafenoquine (TQ) roll out. Robust point of care (PoC) G6PD tests are needed, which are suitable and cost-effective for clinical settings with limited infrastructure. An affordable and competitive test price is needed, accompanied by sustainable funding for the product with appropriate training of healthcare staff, and robust quality control and assurance processes. In the absence of quantitative PoC G6PD tests, G6PD status can be gauged with qualitative diagnostics, however none of the available tests is currently sensitive enough to guide TQ treatment. TQ introduction will require overcoming additional challenges including the management of severely and intermediately G6PD deficient individuals. Robust strategies are needed to ensure that effective treatment practices can be deployed widely, and these should ensure that the caveats are outweighed by  the benefits of radical cure for both the patients and the community. Widespread access to quality controlled G6PD testing will be critical.
    Matched MeSH terms: Diagnostic Tests, Routine/statistics & numerical data
  17. Teo SW, Noorafidah MD, Laili SAL
    Med J Malaysia, 2020 03;75(2):175-177.
    PMID: 32281604
    Nasopharyngeal mass in paediatric population is usually benign and malignant nasopharyngeal tumours such as carcinoma is rare. We report a case of nasopharyngeal carcinoma (NPC) in an adolescent with atypical imaging findings that mimicked a benign mass. This highlights the importance of a comprehensive review on the distinctive radiographic features of paediatric nasopharyngeal mass. We discuss the imaging features of NPC in the paediatric group, which differ from the elderly patients. By recognising these distinctive imaging features, it may help in diagnosing typical case. This case report serves as a reminder that NPC, despite being uncommon, should be considered in the differential diagnosis of a juvenile nasopharyngeal mass.
    Matched MeSH terms: Diagnostic Tests, Routine
  18. Tan ZN, Wong WK, Noordin R, Zeehaida M, Olivos GA, Lim BH
    Trop Biomed, 2013 Jun;30(2):250-6.
    PMID: 23959490 MyJurnal
    Entamoeba histolytica causes amoebic diarrhoea, colitis and liver abscess (ALA). Diagnosis of ALA is difficult, as most patients do not have simultaneous intestinal amoebic infection. At Hospital Universiti Sains Malaysia (HUSM), diagnosis of ALA relies on a combination of clinical findings, ultrasound examination of the liver and serodiagnosis using a commercial kit. In this study, two in-house indirect ELISAs were developed and evaluated. One of the in-house assays utilises E. histolytica crude soluble antigen (CSA) to detect serum IgG specific to the parasite whereas the other uses E. histolytica ether extract antigen (EEA). Preparation of CSA requires a sonicator to lyse the amoeba whereas EEA was prepared by chemically solubilizing the trophozoites. Based on the cut-off value of mean optical density + 3SD, CSA-ELISA showed 100% (24/24) sensitivity and 93.33% (210/225) specificity; while EEA-ELISA showed 91.67% (22/24) sensitivity and 95.11% (214/225) specificity. In conclusion, both the in-house indirect ELISAs were found to be efficacious for diagnosis of ALA; and the EEA is easier to prepare than the commonly used CSA.
    Matched MeSH terms: Diagnostic Tests, Routine/methods*
  19. Tan AF, Sakam SSB, Rajahram GS, William T, Abd Rachman Isnadi MF, Daim S, et al.
    Front Cell Infect Microbiol, 2022;12:1023219.
    PMID: 36325471 DOI: 10.3389/fcimb.2022.1023219
    BACKGROUND: Plasmodium knowlesi causes zoonotic malaria across Southeast Asia. First-line diagnostic microscopy cannot reliably differentiate P. knowlesi from other human malaria species. Rapid diagnostic tests (RDTs) designed for P. falciparum and P. vivax are used routinely in P. knowlesi co-endemic areas despite potential cross-reactivity for species-specific antibody targets.

    METHODS: Ten RDTs were evaluated: nine to detect clinical P. knowlesi infections from Malaysia, and nine assessing limit of detection (LoD) for P. knowlesi (PkA1-H.1) and P. falciparum (Pf3D7) cultures. Targets included Plasmodium-genus parasite lactate dehydrogenase (pan-pLDH) and P. vivax (Pv)-pLDH.

    RESULTS: Samples were collected prior to antimalarial treatment from 127 patients with microscopy-positive PCR-confirmed P. knowlesi mono-infections. Median parasitaemia was 788/µL (IQR 247-5,565/µL). Pan-pLDH sensitivities ranged from 50.6% (95% CI 39.6-61.5) (SD BIOLINE) to 87.0% (95% CI 75.1-94.6) (First Response® and CareStart™ PAN) compared to reference PCR. Pv-pLDH RDTs detected P. knowlesi with up to 92.0% (95% CI 84.3-96.7%) sensitivity (Biocredit™). For parasite counts ≥200/µL, pan-pLDH (Standard Q) and Pv-pLDH RDTs exceeded 95% sensitivity. Specificity of RDTs against 26 PCR-confirmed negative controls was 100%. Sensitivity of six highest performing RDTs were not significantly different when comparing samples taken before and after (median 3 hours) antimalarial treatment. Parasite ring stages were present in 30% of pre-treatment samples, with ring stage proportions (mean 1.9%) demonstrating inverse correlation with test positivity of Biocredit™ and two CareStart™ RDTs.For cultured P. knowlesi, CareStart™ PAN demonstrated the lowest LoD at 25 parasites/µL; LoDs of other pan-pLDH ranged from 98 to >2000 parasites/µL. Pv-pLDH LoD for P. knowlesi was 49 parasites/µL. No false-positive results were observed in either P. falciparum-pLDH or histidine-rich-protein-2 channels.

    CONCLUSION: Selected RDTs demonstrate sufficient performance for detection of major human malaria species including P. knowlesi in co-endemic areas where microscopy is not available, particularly for higher parasite counts, although cannot reliably differentiate among non-falciparum malaria.

    Matched MeSH terms: Diagnostic Tests, Routine/methods
  20. Syarifah Haizan Sayed Kamar, Nasruddin Jaafar
    MyJurnal
    Mothers can be trained to screen caries in their children. The aim of this study is to
    assess the validity of mothers’ caries screening of their preschool children. (Copied from article).
    Matched MeSH terms: Diagnostic Tests, Routine
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