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Mite bites, comet signs and possible mammary prosthesis rejection after returning to a vacation home: a diagnostic
A Laghi1, C Ongaro2, E Moliterni3
1Department of Medicine, Dermatology Unit, Celio Military Hospital, Rome, Italy.
Abstract:
Pyemotes ventricosus is a free-living mite feeding on larvae or nymphs of insects, including moths, beetles, wasps and bees, that are usually found in grain, straw and firewood. When present in great number or when its food is lacking, it could accidentally bite mammals, including humans, causing a highly pruritic self-limiting dermatitis, sometimes followed by a lymphangitis known as "comet sign".We present a singular case of mite lymphangitis that surrounds and delimitates breast prosthesis in a 30-year-old Caucasian woman. Other bite in the lower abdomen did not present comet sign. The patient got the infestation in her vacation home in the South of Italy, uninhabited for 10 months since COVID-19 confinement. We hypothesize that the previous surgery made the lymphatic vessels more prone to inflammation and we compare other insect bites that can occur vacationing in a long period uninhabited room.A delayed diagnosis of comet sign implies a retarded fumigation allowing new mite bites and, in this case, extends the patient's preoccupation about the prosthesis rejection.
Insights
Pyemotes ventricosus mites can cause itchy dermatitis and lymphangitis in humans. A unique case involved mite lymphangitis around breast implants, highlighting potential complications and delayed diagnosis concerns.
Area of Science:
- Dermatology
- Parasitology
- Infectious Diseases
Background:
- Pyemotes ventricosus mites infest stored products and can bite humans, causing dermatitis and lymphangitis (comet sign).
- Infestations can occur in unoccupied dwellings, particularly after prolonged absence.

