Infections - Helminths, infestations, bites, stings

Question 1

Why is cutaneous larva migrans confined to the epidermis ?

Answer 1

Parasite lacks collagen age, which is necessary to disrupt the basement membrane

Question 2

What organism is cutaneous larva migrans caused by

Answer 2

Hookworm. Ancylostoma braziliensis or ancylostoma caninum

Question 3

What is the treatment for cutaneous larva migrans?

Answer 3

Albendazole
Single ivermectin dose 12mg in adults or 150-200mcg/kg in children - this has 80-100% efficacy
Topical ivermectin not helpful

Question 4

Gnathostomiasis can mimic cutaneous larva migrans

Answer 4

True

Question 5

Scabies undertake half of their life cycle in the human skin

Answer 5

False - entire life cycle in the epidermis

Question 6

Each female scabies lays 3 eggs

Answer 6

True

Question 7

Scabies can survive one week off the human host

Answer 7

False, 3 days or fewer

Question 8

What does a scabies burrow look like

Answer 8

Wavy , thread like, greyish white 1-10mm in length

Question 9

Options for scabies treatment in pregnancy

Answer 9

permethrin 5%
sulfur ointment 5-10% for 3D
NOT lindane or crotamiton

Question 10

Treatment regime for crusted scabies

Answer 10

Ivermectin 200mcg/kg Day 1, 2 and again Day 8,9, 15, 22 and 29 in severe cases. Sometimes need 4-6 weeks treatment repeating monthly

• topical keratolytics assist with hyperkeratotic areas 5% sal acid or 25% benzoyl benzoate every 2-3 days for one week then twice week until cure
• permethrin 2nd daily for 1-2 weeks then twice weekly until no more burrows found
• treat secondary bacterial infection

Question 11

Pediculosis capitis louse lives for 30days, and lays 5-10 eggs per day on hair shafts

Answer 11

True

Question 12

Head lice can spread via hair dryers

Answer 12

True

Question 13

What is in KP24

Answer 13

0.5% Maldison (Malathion)

Question 14

Head lice ancillary treatment

Answer 14

Items used by infected person should be machine washed with hot water and tumble dried. Non washable seal in plastic bag for 2 wk
- soak combs and brushes in hot water at least 60degree for 5-10 min

Question 15

Body louse are smaller than head lice

Answer 15

False larger 2.5-4mm length

Question 16

Crab lice is 5mm in length

Answer 16

False 1mm in length

Question 17

Crab lice is caused by pthirus pubis

Answer 17

True

Question 18

Bed bugs are caused by?

Answer 18

Cimex lectularius

Question 19

Bed bugs have a flattened oval body that is red brown in colour and 2-3mm long in adults

Answer 19

False 5-7mm length

Question 20

EXAGERRATED insect bite reactions can represent a manifestation of which malignancy?

Answer 20

Chronic lymphocytic leukaemia and less often other haem malignancies

Question 21

TUNGIASIS are winged fleas

Answer 21

False , wingless

Question 22

Bird mites in australia - Ornithonyssus bursa (domestic starling mite)

Answer 22

True

Question 23

Bird mites cause Profuse eruption of large intensely pruritic weals or papules often symmetrical

Answer 23

False — SMALL weals and often ASYMMETRICAL

Question 24

Seabather’s eruption causes pruritic papules under the bathing suit and in intertriginous areas

Answer 24

True

Question 25

Seabather’s eruption caused by stinging larvae including thimble jellyfish or larvae of sea anemone

Answer 25

True

Question 26

Cercarial dermatitis is associated with transient erythematous, pruritic papular or urticarial eruption away from the site of inoculation

Answer 26

False - at site of inoculation

Question 27

In cercarial dermatitis, contact macules occur within seconds of contact then either disappear or replaced by small papules persisting for days

Answer 27

False within hours

Question 28

Praziquantel is treatment of choice for schistosomes

Answer 28

True , 40-60mg/kg dependent on species