This test is a simple, cheap and rapid test with minimal discomfort to patients, but an uncommon one as it is prescribed by doctors only under certain circumstances. This is performed to distinguish between various blistering conditions. It can be used to detect various cutaneous (skin) infections, especially the ones that have blistering effect. This is usually prescribed in acute circumstances when a quick detect is needed a herpes infection or to distinguish between Stevens- Johnson syndrome and staphylococcal scalded skin syndrome. In the early disease stages, this test may provide false negative or positive results as well due to the methodology. Hence, it is advisable to confirm these test results with a follow up biopsy or PCR (polymerase chain reaction) for accuracy.
No special preparation is required for undergoing this test and neither does it trouble the person in any way. The lab assistant performing the test would follow the necessary procedure to remove a portion of the tissue from the blister for further analysis. However, it is always better to inform the doctor if you have any allergies or any other underlying medical conditions, just to be on the safe side.
This is mostly useful to identify skin infections fast, especially the ones that result in blisters. The findings are usually on the basis of viewing and interpreting single cells (cytology). The various findings are grouped into: Bacterial infections like Bullous impetigo, Staphylococcal scalded skin syndrome Viral infections like herpes simplex and herpes zoster, viral warts, molluscum contagiosum, Hand foot and mouth diseaseFungal infections like candidiasis, histoplasmosis, cryptococcosis, sporotrichosis: Parasites like scabies, and Leishmaniasis The findings are on the basis of various test results like the presence and absence of certain cells, their size, presence and absence of inflammation, and shapes of the bodies found in the tissue.
This test is done on a tissue sample taken from the blister on the body. The procedure goes like this: The sample is to be taken from a fresh blister on the body. The roof of the blister is gently opened out using a blunt scalpel. Then the tissue sample is collected by scraping the base of the lesion/blister. This tissue is smeared onto a fresh microscope slide. It is then allowed to dry and preserved as a specimen for analysis through further stains.