Scabies: Application of the Novel Identify-Isolate-Inform Tool for Detection and Management

Cheng, Tabitha A.; Mzahim, Bandr; Koenig, Kristi L.; Alsugair, Abdulrahman; Al-Wabel, Abdussalam; Almutairi, Bandar Saad; Maysa, Eshmawi; Kahn, Christopher A.

A presumptive diagnosis of scabies can be made based on suggestive clinical features such as nocturnal pruritus, history of contact with scabies, and/or typical appearance and distribution of skin lesions with the presence of burrows. However, achieving a definitive diagnosis depends on identification of mites, eggs, or fecal material using light microscopy. Lesions should be scraped off using a scalpel. With the scalpel, the papule should be scraped multiple times to remove the top (Video Example: Scabies skin scraping technique). Adding a few drops of mineral oil to the skin prior to scraping may help the scraped material to adhere to the blade. Most hospital pathology laboratories will accept scrapings for microscopic evaluations. The pathology protocols for scabies skin scraping methods at two university hospitals are provided here for reference: University of Iowa and University of Michigan. The characteristic microscopic appearance is shown here. Even with ideal technique, however, failure to find mites, eggs, or fecal material is common and does not rule out the disease. 26, 27 The sensitivity of this approach ranges from 40% to 90% and the specificity reaches 100%. 26 Alternatively, the burrow ink test may be used. In this method, ink is absorbed by the burrows and will be visible as wavy lines ( Figure 2 ). 24, 25 This method requires a dark felt tip washable marker or a fountain pen over the affected area and an alcohol swab to clean the surface ink. Any remaining dark ink under the skin signifies presence of scabies burrows ( Figure 2 ). The sensitivity and specificity for the burrow ink test is unable to be calculated based on a French dermatology study. 26 Nevertheless, for any case with concern for scabies in Cheng et al.