Scabies Flashcards
What causes Scabies?
Scabies is caused by the mite Sarcoptes scabiei, which lives and moves in the skin, producing burrows, small blisters, and papules.
What are the characteristic symptoms of Scabies?
Symptoms include intense itching (especially severe at night), burrows (S-shaped ridges), small blisters, papules, scratch marks, and secondary infection with pustules and crusts.
Where on the body do Scabies lesions commonly occur?
Lesions commonly occur between the fingers, sides of the hands and feet, flexor sides of the wrists, armpits, genitals, and buttocks. In infants and small children, the palms, soles, head, and neck are often affected
How is Scabies primarily spread?
Scabies is primarily spread through close personal contact but may also be transmitted through clothing, linen, or towels.
What is essential when treating Scabies?
It is essential to treat all close contacts of the patient and to wash or air clothing and linen for at least 24 hours at the time of treatment.
How should secondary infection associated with Scabies be treated?
Secondary infection should be treated like impetigo for 5 days, and lesions should be closed before applying Scabies treatment.
What is the treatment protocol for adults using Gamma benzene hexachloride (GBH) 1% lotion or cream?
Apply GBH 1% lotion or cream from the neck down, allow it to dry, and wash off after 24 hours. Give 10 ml for adults. Do not use in pregnancy, breastfeeding mothers, or babies under 6 months.
How should children be treated for Scabies with benzyl benzoate 25% emulsion?
For children, dilute benzyl benzoate 25% emulsion with one part water (1:1) and apply for 3 nights, washing off each morning. For infants, dilute with 3 parts water (1:3).
What is the alternative treatment for Scabies in institutional epidemics?
Scabies epidemics in institutions like prisons, army camps, or boarding schools may be treated with ivermectin.
What is post-scabies itch, and how is it treated?
Post-scabies itch often occurs and can be mistaken for inadequately treated Scabies. It is treated with topical steroids.
What criteria confirm a diagnosis of Scabies (A)?
A1: Mites, eggs, or feces on light microscopy of skin samples
A2: Mites, eggs, or feces visualized on an individual using a high-powered imaging device
A3: Mite visualized on an individual using dermoscopy
What criteria are used to diagnose Clinical Scabies (B)?
B1: Scabies burrows
B2: Typical lesions affecting male genitalia
B3: Typical lesions in a typical distribution and two history features
What criteria are used to diagnose Suspected Scabies (C)?
C1: Typical lesions in a typical distribution and one history feature
C2: Atypical lesions or atypical distribution and two history features
What are the history features (H) relevant to diagnosing Scabies?
H1: Itch
H2: Positive contact history with an individual who has an itch or typical lesions in a typical distribution
What is Norwegian (Crusted) Scabies?
Norwegian (Crusted) Scabies is a variant of scabies where skin lesions are extremely massive and extensive, with thick, grey keratoses and crusts that develop on the hands, elbows, knees, ankle joints, and can extend to areas not normally affected by scabies, such as the face, scalp, and nail beds.
Who is most likely to develop Norwegian (Crusted) Scabies?
Norwegian (Crusted) Scabies is seen in severely immunocompromised patients, such as those with AIDS.
Why is Norwegian (Crusted) Scabies highly infectious?
The crusts in Norwegian Scabies are teeming with scabies mites, making them highly infectious to others.
What is the general management approach for Norwegian (Crusted) Scabies?
Treatment is as for regular scabies but may need to be prolonged. Additionally, keratolytics like salicylic acid 5-10% ointment or urea 10% ointment are applied to remove thick crusts.
What specific medications are used in the management of Norwegian (Crusted) Scabies?
Ivermectin (3-12 mg depending on body weight) plus sulphur 5-20% ointment is used in the treatment.
