In this cross-sectional diagnostic study, healthy adults aged 18 and older with suspected, clinical, or confirmed scabies will be recruited. The objective is to determine if the sensitivity of self-collected skin samples for scabies diagnosis is non-inferior to professional sampling, and compare the sensitivity and specificity of the polymerase chain reaction assay (PCR) versus microscopy.
Scabies infestations have significantly increased globally in the last 10-20 years, including a threefold rise in the Netherlands over the past decade. Diagnosing scabies is challenging due to varied symptoms and low sensitivity of current microscopic methods. New diagnostic techniques like PCR, which offer higher sensitivity, are being investigated. The feasibility of self-collected skin samples is being explored to reduce the burden on healthcare services and address issues like autonomy, stigma, and privacy. In this cross-sectional diagnostic study, healthy adults aged 18 and older with suspected, clinical, or confirmed scabies will be included. Primary endpoint is the sensitivity of self-collected versus professional skin samples for diagnosing scabies. Secondary endpoints include sensitivity of skin scrapings and swabs, and the sensitivity and specificity of PCR versus microscopy. Participants will self-collect skin samples during a standard care visit. The process may be slightly sensitive but not painful. There are no direct benefits beyond standard care.
Study Type
INTERVENTIONAL
Allocation
NA
Purpose
DIAGNOSTIC
Masking
NONE
Enrollment
144
All individuals will self-collect skin samples and swabs and fill in a questionnaire. Subsequently, all individuals will see a professional. The professional will collect skin samples and swabs as well.
Radboudumc
Nijmegen, Gelderland, Netherlands
RECRUITINGThe sensitivity of self-collected skin samples for diagnosing scabies
The proportion of self-collected samples collected at the enrolment visit that are tested positive, divided by the total number of participants adjudged retrospectively to have had scabies at their enrolment visit, based on a composite clinical diagnosis.
Time frame: through study completion, an average of one year
The sensitivity of professionally-collected skin samples for diagnosing scabies
The proportion of professionally-collected samples collected at the enrolment visit that are tested positive, divided by the total number of participants adjudged retrospectively to have had scabies at their enrolment visit, based on a composite clinical diagnosis.
Time frame: through study completion, an average of one year
The sensitivity of skin scrapings for diagnosing scabies
The proportion of skin scrapings at their enrolment visit (whether professionally or self-collected) that are tested positive by PCR, divided by the total number of participants adjudged retrospectively to have had scabies at baseline, based on a composite clinical diagnosis.
Time frame: through study completion, an average of one year
The sensitivity of skin swabs for diagnosing scabies
The proportion of skin swabs at their enrolment visit (whether professionally or self-collected) that are tested positive by PCR, divided by the total number of participants adjudged retrospectively to have had scabies at baseline, based on a composite clinical diagnosis.
Time frame: through study completion, an average of one year
The sensitivity and specificity of PCR on skin scraping for diagnosing active scabies infection
The proportion of participants adjudged to have had scabies at their enrolment visit (based on a retrospective composite clinical diagnosis), whose skin scraping at their enrolment visit (whether professionally or self-collected) are tested positive for scabies by PCR, and the proportion of participants adjudged retrospectively to have not had scabies at their enrolment visit whose skin scrapings are tested negative for scabies by PCR.
This platform is for informational purposes only and does not constitute medical advice. Always consult a qualified healthcare professional.
Time frame: through study completion
The sensitivity and specificity of microscopy on skin scraping for diagnosing active scabies infection
The proportion of participants adjudged to have had scabies at their enrolment visit (based on a retrospective composite clinical diagnosis), whose skin scraping at their enrolment visit (whether professionally or self-collected) are tested positive for scabies by microscopy, and the proportion of participants adjudged retrospectively to have not had scabies at their enrolment visit whose skin scrapings are tested negative\* for scabies by microscopy.
Time frame: through study completion, an average of one year