Diagnosis of Scabies can be made by finding the mites, their eggs or scybala (faecal pellets) in skin scrapings. Mites live under the surface of the skin, therefore skin scrapings must be made from the infected area (usually hands, groins, axillas or buttocks).
Select a papule or burrow that has not been excoriated or scratched. The ideal papule to select is one slightly oval or linear with no marks on the surface – no crust.
Scrape vigorously six or seven times with a sterile scalpel blade to remove the top layers of the skin epithelium (little specks of blood may be visible).
Place the material into a labelled container and send to the laboratory for examination.
Other methods have been proposed for obtaining specimens, where a drop of mineral oil is placed on a scalpel blade, allowing mites to adhere to the oil after scraping. |