Guidelines

Investigation and Diagnosis

Usually clinical diagnosis.

If equipment and expertise allow, tests can be done to provide a definitive diagnosis:

• Ink burrow test (black or blue ink applied to the lesion and wiped off to remove surface ink)
  • +ve Finding: dark zigzagged line running across and away from the lesion (due to ink tracking down the mite burrow)
• Skin scrapings microscopy
  • Presence of mites / eggs / mite faecal material confirms the diagnosis

Management

Seek specialist advice if:

• <2 months (rare in this age group and permethrin cream is only licensed for ≥2 months)
• Crusted scabies (hospital admission may be required and investigation for underlying immunodeficiency)

General / Conservative Management

Advise that bedding, clothing, and towels (and those of all potentially infested contacts) should be decontaminated by washing at a high temperature (at least 60°C) and drying in a hot dryer, or dry-cleaning, or by sealing in a plastic bag for at least 72 hours

Anti-Scabies Treatment

Offer:

• Permethrin 5% cream, or
• Single dose oral ivermectin 200 mcg/kg

Both have similar effectiveness, choose based on the following patient factors

• Avoid permethrin if
  • <2 y/o (unlicensed in <2 months)
  • Pre-existing eczema or other skin conditions which may lead to hypersensitivity

• Avoid ivermectin if
  • Pregnant and breastfeeding
  • Severe hepatic impairment
  • <15 kg

Contact Management

All the following should be treated with anti-scabies treatment, even if asymptomatic:

• Household members
• Sexual partners within the past month
• Any other close personal contacts

Post-Scabetic Itch

• Crotamiton 10% cream
• If scabies mites have definitely been eradicated: topical hydrocortisone 1%

Also consider nighttime sedating antihistamine (e.g. chlorphenamine) to improve sleep and reduce scratching

References

Original Guideline