Creepy crawlies…

Dr Maya Mistry

13th April 2011

A 41-year-old man presents with an itchy rash over his arms and abdomen. It has got gradually worse over the past three days

What is the most likely diagnosis?

A. Scabies

B. Pityriasis rosea

C. Erythema multiforme

D. Urticaria

E. Guttate psoriasis

ScabiesClassical Scabies

Female mite burrows in skin (webs of fingers, wrist, heels, armpit, buttocks) and lays eggs

Itch – worse at night and due to delayed IV hypersensitivity reaction to mites/eggs 30 days after initial infection

Only 5-15 mites

Direct contact

Children/young adults

Norwegian Scabies

Very contagious – indirect contact

Institutions

Millions of mites

Scaly ‘crusted’ rash

Management• General advice

– Cut nails– Wash bedding/towels/clothes in hot cycle– Treat household and close contacts even if asymptomatic– Avoid close physical contact until treated– Once treated, itching can last for up to 6 weeks

• Apply washes from chin and ears downwards unless immunosupressed/children/elderly then wash face and scalp also

• Repeat after 7 days

• 1st line– Permethrin 5% cream– For adults and children older than 2 months– Apply to cool skin and after 8-12 hours wash off in hot bath

• 2nd line– Malathion 0.5% liquid– Washed off after 24 hours

Which one of the following is not a recommended management option for head lice?

A. Isopropyl myristate and cyclomethicone

B. Wet combing

C. Dimeticone

D. Malathion

E. Benzyl benzoate

Which one of the following is a recommended management option for head lice in a 3 year old child with atopy?

A. Isopropyl myristate and cyclomethicone

B. Dimeticone

C. Coconut, anise, and ylang ylang spray

• Head lice (eggs are called nits• Suck blood from scalp 5 times/day• 12 lice but 100 eggs

Lice - pediculosis

Body lice – usually in homeless/neglectedStick to clothes fibres not hairCan live up to 30 days off human

• Pubic lice (crabs)

Management• Only treat if see live lice on fine tooth combing

• General advice– All household should check for lice and treat affected simultaneously– No school exclusion

• Wet comb every 2-3 days for 2 weeks– Stop when 3 consecutive sessions no lice seen

• Washes repeat after 7 days– Dimeticone 4% lotion (Hedrin® lotion),

• For all ages • Left for 8 hours then washed off with shampoo

– Isopropyl myristate and cyclomethicone (Full Marks Solution®)• Not suitable for < 2 year olds and skin conditions• Leave for 10 mins, comb using fine tooth, then wash off

– Coconut, anise, and ylang ylang spray (Lyclear SprayAway®)• Not suitable for < 2 year olds and skin conditions and asthma• Leave for 15 minutes, wash hair, then use fine tooth comb.

Fleas

Bedbugs