A 29 y.o. woman presents with a rash.
What is the cause of her rash?
Our patient had Norwegian scabies. Norwegian scabies is a skin infestation of scabies mites that forms thick crusts. The crusts contain large numbers of mites and eggs. It is more severe than common scabies and occurs in people with compromised immune systems, the elderly , the disabled and aboriginal communities in Australia. There are an estimated 4,000 mites per gram of skin. Characteristic burrows are often found in the web spaces of the fingers and toes. The burrow is a short , wavy, gray line on the skin surface.
The burrows of scabies mites
Random trivia
It was described first in Norway by Danielssen and Boeck as an infestation of millions of mites in patients with leprosy.
LIFE CYCLE OF SCABIES MITES
The pregnant female burrows into the skin and lays eggs. After two or three days the larvae emerge and dig new burrows. They mature, mate, and repeat this cycle every two weeks. The skin lesions can be burrows, papules, vesicles or nodules.
The diagnosis is made on a skin scraping,using a wet mount under 40x power
Under 40x power the mite would appear about 1/4 this size
The diagnosis is made on a skin scraping, using a wet mount under 40x power Topical and systemic treatment for our patient’s scabies infestation was initiated with ivermectin and permethrin. She recovered uneventfully.
Mites also infect dogs camels and pigs leading to a condition called sarcoptic mange. Humans can catch the skin condition from dogs but the dog mites cannot complete their life cycle in humans. Humans do develop at rash which looks similar to mosquito bites. Scabies can appear as papules, vesicles or nodules.
mite infestation in a dog
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