Infections

Question 1

HPV vaccination - which HPV covered?

Answer 1

6, 11, 16, 18, 31, 33, 45, , 52, 58

Question 2

Crusted scabies - tx

Answer 2

admission to hospital
isolation w contact precautions
keratolytic (eg SA)
cut nails short
topical permethrin daily until 2 neg scrapings 3 days apart
oral ivermectin 200mcg/kg (adult/child > 15kg) for 3/5/7 doses
– day 1, 2, 8, 9, 15, 22, 29
consider community checking/tx - social worker etc

Question 3

Ix in crusted scabies

Answer 3

confirm diagnosis (scraping - should be easy, KOH + formal)
check for associations/ comorbidities (fungal, strep infection, neurological conditions, immunodeficiencies, aboriginal health - diabetes, strep, GN, rheumatic fever, liver/kidney disease)
pre-tx - ELFTs, FBC, pregnancy

Question 4

syphilis timeline?

Answer 4

3 weeks chancre
4 week unilateral LN
5 weeks bilateral LN
4-6 weeks serology positive
macular rash 8 weeks
papular rash 12 weeks
condylomata lata 6 months

Question 5

progression of syphilis?

Answer 5

all primary progress to secondary
of secondary:
--- 1/3 clear 
--- 2/3 progress to latent --- 25% relapse to secondary
of latent:
-- 1/3 clear w neg RPR (cleared)
-- 1/3 no symptoms w pos RPR (true latent)
-- 1/3 progress to tertiary
of tertiary:
-- 50% die

Question 6

Infective DDx of recurrent genital ulcers

Answer 6

• HSV
• syphilis
• chancroid (Haemophilus ducreyi)
• Granuloma inguinale (Donavanosis, klebsiella-like organism, these ulcerate)
• lymphogranuloma venereum (chlamydia trachomatis — this is ‘bubo’)
• EBV (lipschutz ulcer)
• TB
• HPV
• CMV

Question 7

Non-infective DDx of recurrent genital ulcers

Answer 7

• immunobullous (eg MMP, pemphigus vulgaris, bullous pemphigoid)
• FDE
• erosive LP
• Crohn’s disease
• lichen sclerosis
• contact dermatitis

Question 8

Measles clinical presentation

Answer 8

Prodrome - coryzal symptoms rhinorrhoea, conjunctivitis, fever,
Day 2 Koplik spots - buccal mucosa opposite premolar, white/blue on red areolar
Day 4 rash - morbilliform/ maculopapular, forehead/face –> trunk + limbs within 24H
Rash fades by day 10 with brownish staining + fine desquamation

Question 9

Complications of measles

Answer 9

secondary infection
Pregnancy complication (premature delivery, spontaneous abortion, maternal infection)
pneumonia, diarrhoea, otitis media
encephalitis
death

Question 10

Rubella clinical presentation

Answer 10

Prodrome (though less unwell than with measles)
Forschheimer sign (petechia on soft palate) during prodrome/ first day of rash
Rash from face –> trunk + limbs becoming coalescent
More pink than red (vs measles)

Question 11

Varicella risks in pregnancy

Answer 11

Risk of maternal infection
Risk of foetal varicella syndrome
Risk of neonatal varicella
– foetal varicella syndrome has the highest risk in weeks 13-20

Question 12

What is foetal varicella syndrome + how to prevent it

Answer 12

Foetal varicella syndrome - foetal exposure highest risk weeks 13-20

• microcephaly, aplasia cutis, limb hypoplasia, low birth weight, neurological deficits, intellectual impairment
• prevention - if non-immune pregnant person exposed, give Varicella Ig within 96H + consider prophylactic antivirals (valtrex 1g %DS for 7 days)
• if infection occurs, start antivirals

Question 13

Risks for neonatal varicella

Answer 13

• if maternal infection 7 days prior to 2 days after delivery - high risk neonate
• isolate newborn + consider varicella Ig + antivirals