Bedbugs

Bedbugs are ectoparasitic arthropods of the Cimicidae family that feed on blood and are primarily transmitted via direct contact with infested beds or other furniture. They typically hide during the day and venture out for a blood meal at night. Symptoms of bedbug dermatitis include painless hemorrhagic punctum at the sites of the bites, typically followed by pruritic 2–5 mm erythematous maculopapular lesions within hours to days. The diagnosis is confirmed based on the appearance of the lesions and signs of bedbug infestation (e.g., exoskeletons) in the patient's environment. Management focuses on symptomatic treatment of pruritus and decontamination of all furniture and textiles. Complications include secondary infections (e.g., folliculitis) and psychological effects (e.g., anxiety and hypervigilance).

• Pathogens: ectoparasitic arthropods of the Cimicidae family ^[1]
  • Cimex lectularius (common bedbug)
  • Cimex hemipterus (tropical bedbug)
• Transmission: direct contact with infested beds and other furniture and/or travelers who bring home bedbugs or their eggs (e.g., on clothes, in luggage) from stays in infested residences
• Risk factors
  • Crowded living conditions
  • Travel to a location with an infestation

Bedbug infestations occur worldwide, primarily in temperate and tropical regions. ^[2]

Bedbug dermatitis can be hard to differentiate from other skin conditions and reactions to other arthropod bites. ^[1][3]

• Bedbug dermatitis ^[1][3]
  • Location and pattern of bites
    • Most commonly on skin regions that are typically uncovered during sleep (e.g., neck, face, arms, hands)
    • Often clustered and/or in linear pattern, i.e., “breakfast, lunch, and dinner” pattern ^[1]
  • Appearance
    • Painless hemorrhagic punctum may initially be visible at the sites of the bedbug bites.
    • Bites typically develop into 2–5 mm erythematous maculopapular lesions (often pruritic) within hours or days. ^[2]
    • Wheals, vesicular lesions, or, less commonly, bullae or cutaneous nodules may be present. ^[1][3]
  • Duration: spontaneous resolution within 1–2 weeks ^[1][2]
• Associated symptoms: psychological distress, e.g., sleep deprivation, hypervigilance ^[1]

Bedbug bites are painless. Bedbug dermatitis, a local cutaneous inflammatory reaction, develops over hours to days. ^[1][3]

• Suspect bedbug dermatitis based on risk factors and the appearance of the lesions. ^[1][3]
• Confirm the diagnosis based on clear signs of bedbug infestation in the patient's environment, e.g.:
  • Bedbugs in various stages of development
  • Exoskeletons
  • Feces
• The patient or another layperson can inspect the environment, but a pest control service may be necessary. ^[1][3]
• Traps may aid detection. ^[1]

Bedbug dermatitis management ^[1]

Management is supportive. ^[3]

• Advise patient to wash lesions with soap and antiseptic solution. ^[1]
• Treat pruritus as needed, e.g., using: ^[1]
  • Topical corticosteroids, e.g., hydrocortisone 1%
  • Antihistamines
• Prescribe topical or systemic antibiotic therapy in the event of secondary bacterial infection, e.g., purulent SSTI. ^[2]

Treat cohabitants with similar symptoms if necessary.

Eradication of infestation ^[1]

• Heat treatment, e.g., washing, steaming, and use of heating tents ^[1][3]
  • Bedbugs are killed:
    • Within 1 minute at temperatures ≥ 140°F (60°C)
    • Within 2 hours at temperatures ≥ 120°F (48.9°C)
• Cold treatment
  • Freezing at ≤ -4°F (-20°C) for at least 2 hours ^[1]
  • Freezing at ≤ 23°F (-5°C) for at least 5 days ^[3]
• Physical removal
  • Vacuuming with a sealable vacuum bag
  • Brushing and cleaning surfaces and luggage to remove eggs
• Insecticides, e.g. pyrethroids, are often ineffective due to widespread bedbug resistance.

Professional extermination is often necessary as part of an integrated pest management strategy.” ^[3]

• Local: secondary infection caused by scratching, e.g., impetigo, cellulitis, folliculitis ^[1][3]
• Psychological: e.g., phobias, anxiety, avoidant behavior, delusional parasitosis, shame, social isolation ^[1]
• Systemic (very rare) ^[1][3]
  • Diffuse urticaria, angioedema, anaphylaxis
  • Anemia
  • Asthma

There is no evidence that bedbugs transmit diseases to humans. ^[1][3]

We list the most important complications. The selection is not exhaustive.