Risk factors for crusted scabies:
(1) immunosuppression and/or compromised immunity
(1a) AIDS
(1b) infection with HTLV-I
(1c) status post organ transplantation
(1d) leukemia or malignant lymphoma
(1e) corticosteroid therapy or other immunosuppressive therapy
(1f) lepromatous leprosy
(1g) severe malnutrition
(1h) diabetes mellitus
(2) collagen vascular disease (SLE, rheumatoid arthritis, vasculitis, etc.)
(3) neurologically impaired persons
(3a) elderly with cognitive deficiency or disability from stroke
(3b) spinal cord injury
(3c) skin anesthesia
In a patient with one or more risk factors, the presence of a skin disorder (eczema, dermatitis, hyperkeratosis, etc.) - especially one associated with pruritus - should alert the clinician to examine the patient for scabies.
