| How is scabies presentation and tx modality? | • Scabies treatment includes a two-pronged approach. The patient and the environment must both be treated. Two topical treatments separated one week apart with a prescription anti-scabietic medication are recommended
• Apply topical medication from the neck down and leave on overnight; for infants and the elderly, include the face and scalp
• Itch and lesions can persist for 2-4 weeks after successful treatment, referred to as “post-scabietic” pruritus or dermatitis. This is not a treatment failure, rather it represents the body’s response to dead mites |
| What is scabies? | • Sarcoptes scabiei (scabies) affects patients of all ages and all socioeconomic classes, although it is more common in women and children
• Immunocompromised individuals and those in congregated facilities
(e.g., nursing homes) are more prone to infestation
• Most infections occur from direct contact with an infected individual; however, fomites can transmit infection |
| How is presentation of scabies? | • The time from initial infestation to symptoms is typically 3-4 weeks. Once sensitized to the mite, re-infestation results in symptoms within 1-2 days
• Papules may commonly involve the axillae, breasts, umbilicus, penis, scrotum, wrists and finger webs
• The scalp and head are more frequently involved in infants, elderly and immuno-suppressed individuals
• The hallmark feature is itching at night |
| What are burrows? | • Burrows are linear markings in the skin due to the movement of the mite
• They are 1-10 mm in length and are most readily found in the interdigital spaces, wrists and elbows |
| How do we identify a mite? | • The scabies mite is 0.35 x 0.3 mm in size and too small to be seen by the naked eye
• Females lay about three eggs per day, which hatch in four days
• Most patients have less than 20 mites on the skin at a time
• Pruritus might occur within 24 hours after a subsequent reinfestation
• Scabies in adults frequently is sexually acquired,especially in genital area, although scabies in children usually is not |
| How is norwegion scabies? | • This is an aggressive infestation that usually occurs in immunodeficient, debilitated, or malnourished persons, including persons receiving systemic or potent topical glucocorticoids, organ transplant recipients, persons with HIV infection or human Tlymphotrophic virus-1-infection, and persons with hematologic malignancies
• Presents with thick, scaly, white-gray plaques with minimal pruritus that is often localized to the scalp, face, back, buttocks and feet
• Fissures provide an entry for bacteria leading to increased risk of sepsis and death
•Immunocompetent persons who come into contact with crusted scabies develop typical scabies (not Norwegian scabies) |
| How is scabies tx? | • Environmental care includes washing all clothing and linens used within the last week in hot water and drying on high heat. For items that cannot be washed, seal items in bags for at least 3 days
• Isolation from other people is unnecessary as the causative organism cannot jump or fly, and can survive for only approximately 72 hours away from the skin
• Subject and his contact (family, friends..)
• Benzyl benzoate 10%: 1 application in the evening after a hot shower except face and scalp, keep 12 to 24 hours. Change clothes, sheets, clothes at 50-60 ° C or lindane powder
• Pyrethynoides (SPREGAL) can be used in pregnant women and infants. Permethrin 5% cream applied to all areas of the body from the neck down and washed off after 8–14 hours |
| What are medications for scabies? | • Ivermectin 200μg/kg if failure of topical treatment, HIV, elderly, community.. repeated in 2 weeks
• In Norwegian scabies: topical scabicide and oral ivermectin 200 ug/kg on days 1,2,8,9, and 15
• Tetanus vaccination
• Treat secondary infections, STI’s |
| How is persistent pruritis after tx? | • The rash and pruritus of scabies might persist for up to 2 weeks after treatment
• recontamination
• Contact dermatitis to the product
• psychogenic pruritus
• Inadequate treatment
• dermatitis due to scabies
• Overtreatment with irritation |
| How is tx of crusted scabies? | • Combination therapy is typically used in crusted scabies. Multiple doses of oral ivermectin 200 mcg/kg/dose depending on the severity of infection
• Topical permethrin 5% 1-2 x weekly. Frequently more than two treatments are required
• Given the high mite burden, patients with crusted scabies need to be isolated, and strict barrier nursing procedures instituted to avoid outbreaks in health care facilities |
