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Dual Point-of-care Test for the Diagnosis of Yaws (YARADI)

The safety and scientific validity of this study is the responsibility of the study sponsor and investigators. Listing a study does not mean it has been evaluated by the U.S. Federal Government. Read our disclaimer for details. Identifier: NCT01841203
Recruitment Status : Completed
First Posted : April 26, 2013
Last Update Posted : November 18, 2014
Papua New Guinea Institute of Medical Research
Papua New Guinea National Department of Health, Disease Control
Divine Word University
Barcelona Centre for International Health Research
Information provided by (Responsible Party):
Oriol Mitja, Lihir Medical Centre

Brief Summary:
A dual POC immunoassay simultaneously detecting non-treponemal and treponemal antibodies was developed for the diagnosis of infections with T. pallidum. The assay is designed for use in resource-limited settings where challenging conditions (such as lack of electricity, running water, or laboratory equipment) commonly exist. We sought to compare performance of the dual-POC assay for diagnosis of yaws infection with that of the RPR and TPHA as reference standards.

Condition or disease

Detailed Description:

Yaws is an infectious disease caused by Treponema pallidum subspecies pertenue, a bacterium which closely resembles the causative agent of syphilis, and is spread by skin to skin contact. In the field, yaws is diagnosed on the basis of epidemiological context, evocative symptoms and signs and positive serological tests or dark field microscopy. The darkfield microscopy is not easy to perform , hence the interest in serological tests. The serological tests used to confirm yaws are the same as those used to diagnose syphilis. Yaws serologic diagnosis relies on testing for non-treponemal and treponemal antibodies. These antibodies differ markedly with respect to antigenic reactivities and kinetics during the disease process.

Historically screening for yaws has involved the use of nontreponemal tests, such as rapid plasma reagin or venereal disease research laboratory. Positive results of nontreponemal tests of specimens are then confirmed using a more specific treponemal test, such as Treponema pallidum haemagglutination. However, the equipment and personnel requirements for conducting and interpreting these laboratory-tests are rarely available in low-resource settings in developing countries where yaws occurs.

Rapid treponemal tests which detect antibodies to T. pallidum antigen have become popular for the diagnosis of venereal syphilis due to their many advantages. These tests that can be performed outside a laboratory setting with minimal training and using blood collected by a finger prick, which makes them extremely useful in remote areas where laboratories are not available. However, the rapid treponemal tests for syphilis detect treponemal antibodies, which limits their use for interpretation of the disease status since they cannot distinguish between active and past or treated infection.

A combined point-of-care (POC) test which detects both treponemal and non-treponemal antibodies has recently been evaluated for the diagnosis of syphilis, and appears promising for yaws diagnosis. The use of the dual POC test would result in the ability to both screen and confirm the serological status of patients with suspected yaws within 15 minutes and give a better indication of active disease.

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Study Type : Observational
Actual Enrollment : 703 participants
Observational Model: Cohort
Time Perspective: Prospective
Official Title: Evaluation of a Rapid Dual Point-of-care Assay for Targeting Antibiotic Treatment for Yaws Eradication: a Prospective Descriptive Study
Study Start Date : April 2013
Actual Primary Completion Date : November 2013
Actual Study Completion Date : November 2013

Resource links provided by the National Library of Medicine

DPP/RPR-TPHA comparison
The evaluation of T1 (treponemal line) will be conducted by using the T1 positivity identified by naked eye or automated reader to compare with that of TPHA; while the evaluation of T2 (non-treponemal line) will be conducted by using the T2 positivity identified by naked eye, or automatic reader at cut-off value of 20, to compare with the result of RPR.

Primary Outcome Measures :
  1. To determine the accuracy of the dual-test as compared to recognized standard methods [ Time Frame: 1 month ]

    Sensitivity and Specificity as compared to RPR and TPHA

    1. Proportion of actual TPHA/RPR positives which are correctly identified as such by DPP (dual-test)T1 and T2 respectively
    2. Proportion of TPHA/RPR negatives which are correctly identified as such by DPP (dual-test)T1 and T2 respectively

Secondary Outcome Measures :
  1. Accuracy of DPP in whole blood and plasma [ Time Frame: 1 month ]

    Specimens will be randomly tested using DPP, either in plasma or blood.

    Sensitivity and Specificity of DPP in whole blood and DPP in plasma will be compared.

  2. Accuracy of DPP determined by Naked eye and Reader [ Time Frame: 1 month ]

    Specimens will be tested using DPP, read by naked eye and also using automated reader.

    Sensitivity and Specificity of DPP result read by naked eye and DPP using automated reader will be compared.

Information from the National Library of Medicine

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Ages Eligible for Study:   2 Years to 15 Years   (Child)
Sexes Eligible for Study:   All
Accepts Healthy Volunteers:   No
Sampling Method:   Non-Probability Sample
Study Population
Patients will be recruited from Lihir Island villages in April 2013. This community has been described previously. We will conduct community-based surveys and we invited children aged 1 - 15 years suspected to have yaws by clinical examination to participate in the study. All children for whom a parent or guardian gives written informed consent will be included consecutively

Inclusion Criteria:

  • Children from 2 to 15 years with clinical suspicion of active yaws

Exclusion Criteria:

  • Persons who are unable to sustain venipuncture; persons who do not provide an informed consent, or withdraw consent

Information from the National Library of Medicine

To learn more about this study, you or your doctor may contact the study research staff using the contact information provided by the sponsor.

Please refer to this study by its identifier (NCT number): NCT01841203

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Papua New Guinea
Karkar Island
Marup village, Madang, Papua New Guinea
Lihir Medical Centre
Londolovit, New Ireland Province, Papua New Guinea, 034
Sponsors and Collaborators
Oriol Mitja
Papua New Guinea Institute of Medical Research
Papua New Guinea National Department of Health, Disease Control
Divine Word University
Barcelona Centre for International Health Research

Publications automatically indexed to this study by Identifier (NCT Number):
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Responsible Party: Oriol Mitja, MD, Lihir Medical Centre Identifier: NCT01841203     History of Changes
Other Study ID Numbers: YARADI
First Posted: April 26, 2013    Key Record Dates
Last Update Posted: November 18, 2014
Last Verified: November 2014
Keywords provided by Oriol Mitja, Lihir Medical Centre:
Rapid tests
non-treponemal serology
Additional relevant MeSH terms:
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Treponemal Infections
Gram-Negative Bacterial Infections
Bacterial Infections
Skin Diseases, Bacterial
Spirochaetales Infections
Skin Diseases, Infectious
Skin Diseases