Bedbugs
Bedbugs (Cimex lectularius and Cimex hemipterus) are blood-feeding insects that hide in bedding, furniture, and cracks by day and crawl to a sleeping host at night, producing painless bites that erupt as pruritic, linearly clustered papules on exposed skin. Diagnosis is clinical, and first-line treatment is itch control with a topical corticosteroid, with or without an oral antihistamine, alongside eradication of the infestation with heat and, when needed, professional pest management.
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What this article covers
- Overview
Bedbug bites are the cutaneous reaction to nocturnal feeding by Cimex lectularius (or Cimex hemipterus): these red-brown, wingless insects live in floorboards, walls, vents, bedding, and furniture…
- Epidemiology
Bedbugs can affect patients of all ages and are not confined to any single population.
- Risk factors
Recent travel with lodging in an infested hotel or other shared accommodation.
- Pathophysiology
Cimex lectularius (and C. hemipterus) hide in cracks, floorboards, walls, vents, bedding, and furniture during the day and do not colonize the human body.
- Clinical features
This is a clinical diagnosis with no formal criteria set: the defining pattern is scattered papules confined to skin that was exposed while sleeping, arranged in a linear or clustered "breakfast…
- Differential diagnosis
Scabies: intensely pruritic burrows and crusted papules or nodules concentrated in the interdigital spaces, wrists, and genitals, confirmed by mites, eggs, or scybala on skin scraping; unlike bedbug…
- Diagnosis
Diagnosis is clinical: there is no formal criteria set, and the diagnosis rests on the characteristic linear or clustered pattern of pruritic papules confined to skin exposed while sleeping, together…
- Management
First, eradicate the environmental source of the infestation, since eradication is critical and no drug treats the bite itself: arrange professional extermination as part of an integrated…
- Complications
Secondary bacterial infection of an excoriated bite is the main treatable complication and should be treated only when it is clinically present.
- Prognosis
Individual bites are self-limited and resolve within 1 to 2 weeks with symptomatic care.
- Prevention
Run bedding and clothing through a high-temperature dryer for 30 minutes after travel or exposure to a potentially infested environment, since washing alone generally does not kill bedbugs.
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