Acne - Rx with COCP

High oestrogen pills better at reducing sebum production: 50mcg daily versus <35mcg daily

Don't use cyproterone acetate without contraception in women as if fall pregnant, can damage male fetus

--> consider using in COCP

The progestins dienogest and drospirenone have anti-androgenic effects, however, desogestrel does not.

Importance of Symptoms in Dx of Skin Disease: Scabies vs Shingles

A recent case of a couple with scabies

Symptoms first developed towards the end of a holiday in a tropical forest setting

Each had similar symptoms to the other

Principal symptom was pruritus (itching and scratching)

Both cases responded very well to 2 doses of oral ivermectin, 7 days apart

About 3 weeks later, one of the partners re-presented with a rash and reported to staff as scabies that hadn't settled fully

However, the principal symptom was pain, with a mild itchy feel at times

The diagnosis was Herpes zoster (shingles) affecting the Left C6 distribution

This case is due for review in a few days


KEYS TO DIAGNOSIS IN THESE CASES

1. SYMPTOMS
1. SCABIES IS ASSOCIATED WITH INTENSE PRURITUS
2. SHINGLES IS ASSOCIATED WITH SIGNIFICANT PAIN
2. DISTRIBUTION
1. SCABIES HAS A CLASSIC DISTRIBUTION, INCL GROIN, BREASTS, BUTTOCKS, WRISTS & ANKLES
2. HERPES ZOSTER PRESENTS IN A DERMATOME DISTRIBUTION

Importance of Symptoms in Dx of Skin Disease: Scabies vs Shingles

A recent case of a couple with scabies

Symptoms first developed towards the end of a holiday in a tropical forest setting

Each had similar symptoms to the other

Principal symptom was pruritus (itching and scratching)

Both cases responded very well to 2 doses of oral ivermectin, 7 days apart

About 3 weeks later, one of the partners re-presented with a rash and reported to staff as scabies that hadn't settled fully

However, the principal symptom was pain, with a mild itchy feel at times

The diagnosis was Herpes zoster (shingles) affecting the Left C6 distribution

This case is due for review in a few days


KEYS TO DIAGNOSIS IN THIS CASE

1. SYMPTOMS
1. SCABIES IS ASSOCIATED WITH INTENSE PRURITUS
2. SHINGLES IS ASSOCIATED WITH SIGNIFICANT PAIN
2. DISTRIBUTION
1. SCABIES HAS A CLASSIC DISTRIBUTION, INCL GROIN, BREASTS, BUTTOCKS, WRISTS & ANKLES
2. HERPES ZOSTER PRESENTS IN A DERMATOME DISTRIBUTION

Balanitis (glans) + Posthitis (foreskin) - an approach to Mx

If appearance is non-specific (e.g. no visitible warts or other lesions)
And Is not severe -> trial of Rx
--> Hydrozole (OTC) or Hydroform (S4) cream
= 1% hydrocortisone + antifungal (clotrimazole and clioquinol, respectively)

If no improvement after 3 days -> review and ?investigate

Consider primary skin disease, in particular

• psoriasis
• dermatitis (eczema; seborrhoeic dermatitis)
• lichen sclerosis

Consider Ix

• swabs for mcs and HSV PCR
• urine PCR for chlamydia and gonorrhoea
• ?formal STI screen
• including Ix sexual partner/s

?fasting BSL


General Mx for all cases

• foreskin hygiene
• low irritant products for washing and showering

Scabies - Dx and Rx

Pathogenesis
infestation --> immune system sensitised to mite and mite-related products incl eggs
--> symptoms appear

Mite count usually 10-15, but can reach thousands in Norwegian (Crusted) Scabies

Dx
clinical
v itchy
bilateral
wrists, ankles, groin/genitals/buttocks, waist etc
often no burrows to see, especially in warm climate

Rx
2 Rx, one week apart
topical
"Lyclear" (permethrin cream)
OK from 2 months old but must be > 15 kg
Head-to-toe at bedtime. Wash off in the morning.
oral
ivermectin ("Stromectol")
150-200 mcg per kg
100kg = 15 - 20 mg
=> 5 or 7 tablets (each 3mg)
"Ready-reckoner" -  adults 15 mg; children 6 mg

Hot wash bed linen, towels, clothing
Rx family and close contacts
(significant incidence of asymptomatic cases => carriers)

Pets don't harbour human mites
=> can't give you scabies; no need to Rx

Response to Rx usually within 3 days (most resolved in 2 weeks), 
but pruritus can remain for up to 2 months

Dx Tinea (corporis) vs Granuloma Annulare

Tinea => border is scaly


Granuloma Annulare => border is non-scaly

Dx Acne Vulgaris vs Acne Rosacea

Vulgaris => comedones (keratin plugs in pilosebaceous unit) - white or black (if oxidised)


Rosacea => no comedones


NB:
Important DDx of (white heads) comedones = Milia  |  Usually found in infra-orbital/cheek regions

Milia = keratin "bleb" vs keratin "plug" in vulgaris (forming a comedone)