Common viral rashes Flashcards
Papule
Elevated, solid region, <1cm
Macule
Flat, solid region, <1cm
Patch
Flat, solid region >1cm
Plaque
Flat, elevated region, >1cm
Nodule
Elevated, solid lesion, >1cm
Vesicle
Elevated, fluid-filled lesion, >1cm
Pustule
Elevated, pus-filled lesion >1cm
Bulla
Elevated, fluid-filled lesion >1cm
How to describe a rash
- Size
- Shape
- Colour - erythematous/purpuric/hyper- or hypo- pigmented
- Border - well demarcated or irregular
- Morphology - macular/papular/nodular/pustular
- Secondary morphology - scaly/eroding/ulcerating/fissuring
- Distribution
Shingles
Caused by varicella zoster
Itchy, painful, blistering rash
Common in older patients, cancer patients and immunocompromised
Can spread to eyes and cause scarring and blindness
Start acyclovir (antivirals)
Molloscum contagious
Itchy, highly contagious rash with pearly white papule and umbilicate appearance
Common in children and immunodeficient
Facial molloscums = AIDS
Tx: conservative, most will self resolve
Coxsackie virus
Hand, foot and mouth
Enterovirus
Highly infectious, causes mild illness
Tx: analgesia for oral lesions
Pityriasis rosea
Potentially caused by herpes - unknown
‘Herald patch’ before onset of x-mas tree pattern rash
Itchy byt asymptomatic
Antihistamines if needed
Erythema infectiosum
Parvovirus B19
‘Slapped chee’ appearance, generally self limiting in young children but can cause arthropathy in adults, aplastic anaemia in pts with blood disorders and causes spontaneous abortion in pregnant women
Rash = not infectious
Causes abortion if contract in first trimester
Microbes increasing risk of spontaneous abortion
Tozoplasmosis, rubella, HSV
When do you get your 2 MMR vaccines
1st dose at 12 months, 2nd at 3y4m
Measles
Measles morbillivirus
- 4 phases: incubation (7-14 days, no sx), prodrome (10-12 days, fever, malaise, conjunctivitis, spots and cough), exanthem (4-5th day, rash appears on face or behind ears and fades within 3-4 days) and recover (cough for 1-3 weeks)
- Dx: swab for PCR, blood IgM and IgG
- starts in mouth and spreads to rash within 2 days
- rarely affects palms and soles of feet
Rubella
Rubivirus
Asymptomatic bar rash starting on face
Infectious from 7 days pre-rash to 7 days post
Intra-uterine death, abortion and birth defects
Analgesia, fluids and isolation
Mumps
Rubulavirus Highly infectious - incubation 14-25 days Swelling of parotid glands Usually no rash Analgesia and fluids
Oral HSV
Oral caused by HSV 1, genital by HSV2
Sx: fever, malaise, sore throat, paraesthesia
- Complications: dehydration, herpetic whitlow, eczema
- Only consider oral antivirals in severe infections or immunocompromised peoplpe
