2/18 Viral Infections and Exanthems Flashcards
What are warts?
Who is the culprit?
Where do they normally affect?
benign, self-regressing epithelial cell lesions within 2 years; likely due to cell-mediated response
HPV
affects epithelial cells (warts) of skin and mucosa
What HPV subtypes are oncogenic? Which ones are non-oncogenic?
Why should women worry?
What is Gardasil?
oncogenic: 16/18
non-oncogenic: 6/11
Women < 30: HPV infections transient; will resolve
Women age >30: persistent infection - risk of cervical cancer
Gardasil: highly effective in preventing cervical cancer, and other anogenital diseases including genital warts caused by HPV 6, 11, 16, and 18
Name these types of warts.
What are their general features?
Where do they commonly affect?
1) Common warts - papillomatosis hyperkeratotic surface with uniform mosiac pattern on the surface with punctate microhemorrhages; commonly seen in places that are prone to trauma. Scratching can spread the warts!
2) Plantar warts - callus or corn-like lesions with painful/pain
3) Filiform/Digitate Warts - hyperkeratotic, elongated papules; often on the face/neck area (where the skin is really thin)
4) Plane/Flat warts- smoother, slightly elevated keratotic papules; usually reddish brown; present on the face, dorsum of hands, elbows, knees, and shin; difficult to eradicate
What is this?
What are the common features?
What causes it?
Seborrheic keratosis
Common benign skin growth that vary in shape and color
Look like melanomas or moles; commonly mistaken for wart
noncancerous benign skin growth that originates in keratinocytes; not viral
What does this patient have?
How can you tell?
Seborrheic keratosis
Common benign skin growth that vary in shape and color - look like melanomas or moles
What are the common features of a common wart?
- Hyperkeratotic surface
- Papillomatosis
- Mosaic surface pattern
- Punctate micro hemorrhages
What does this patient have?
How do you know? (general features?)
Where does it affect?
common wart
- Hyperkeratotic surface
- Papillomatosis
- Mosaic surface pattern
- Punctate micro hemorrhages
usually affects surfaces that are prone to trauma (hands, fingers, knees, elbows)
What does this patient have?
how do you know?
How is this different than a corn?
Plantar wart
callus, corn-like lesions with painful or painless hyper-keratotic areas
(if it’s painful it must be treated)
on feet
Plantar warts: shaving callous reveals tips of blood vessels (L)
Corns: shaving callus reveals smooth hard base (R)
What does this patient have?
How do you know? (general features?)
Where does it affect?
Filiform/Digitate Wart
Hyperkeratotic, elongated projecting papule
often on surfaces with thin skin
What doest his person have?
How do you know? (general features)
Where does it commonly affect?
Plane or flat wart
smooth, slightly elevated keratotic papule with a reddish/brown color
affects the face, dorsum of hands, elbow, knees and shin
hard to eradicate!
Your patient comes in and asks, Yo doc, what’s up with this shit?
What do you tell him?
What causes it?
genital wart - soft papillary projections on the genital mucosa and surrounding skin (moist skin surfaces)
HPV
What is this?
What causes it?
Anal wart - soft papillary projections on the genital mucosa and surrounding skin (moist skin surfaces)
HPV
Patient comes in tells you that he has these weird flat lesions on his elbow fossa, hands, and general areas of his skin.
What is it? How do you know?
Molluscum Contagiosum (Poxviridae)
Multiple, dome-shaped, pink, papules, 2-5 mm
Umbilicated and contain a caseous plug.
What is Molluscum Contagiosum?
What is the culprit?
How is it spread in children? adults?
Who is at higher risk of an extensive infection?
What are the physical findings? (where does it usually occur?)
This normally normally resembles herpes virus infection. How is it different?
culprit: pox virus that replicates in epidermal cells, causing hyperplasia
spread in children: sexual abuse
spread in adults: physical contact/veneral transmission
more extensive infections observed in patients with atopic dermatitis, HIV patients
Multiple, dome-shaped, pink, papules, 2-5 mm; umbilicated and contain a caseous plug.
usually occur in the same atopic areas (hands, elbow fossa, neck, face)
difference from herpes virus:
Molluscum Contagiosum has a solid feel to it
Herpes is a vesicle
What does this patient have?
How can you tell?
Multiple, dome-shaped, pink, papules, 2-5 mm
umbilicated and contain a caseous plug.
Patient complains of this rash after you had prescribed her penicillin. What kind of rash is this?
maculopapular rash
What does this patient have?
What causes it?
What are some features of it in children? adults? fetuses?
Erythema infectiosum
ParvoB19
Children: slapped cheek (facial erythema), followed by a net-like pattern erythema over the trunk and buttocks; goes away without scarring
Adults: arthritis/arthralgia; may also cause anemia + aplastic crisis
Fetus: spontaneous abortion due to hemolytic anemia in fetus
Patient comes into you with these symptoms. You ask him for a history and discover that he’s recently been on a cruise ship for a week. What do you suspect that he has? How do you tell?
Where do his lesions normally show up?
What are some features of the lesion?
Hand Foot & Mouth Disease
Coxsackievirus A16 and enterovirus 71
Cutaneous lesions on hands, feet, and buttocks
Lesion: erythematous macule on which a central, gray, oval vesicle develops.
Herpes viruses
What are the 2 types? What areas do they like to infect?
What is their mechanism of inecting skin?
When is it normally transmitted?
What are the characteristic skin lesions? Where can you normally find them?
Herpes resembles this other skin disease. How is it different?
HSV 1
- orolabial (cold sores, fever blisters)
- primary genital herpes
HSV 2
- genital
- >95% of recurrent genital herpes
mechanism of infection:
- infects epithelial cells via intact mucosa or abraded skin
- viral replicates locally but is then transported back to DRG, where it establishes latency (and avoids host immune response)
- stress (sunlight, trauma, heat, cold, infections, menstruation) causes reactivation
- virus transported back to body surface to replicate in epithelial + dermal cells
Transmission occurs mostly during asymptomatic phase
Skin lesions: grouped, umbilicated, and uniformed sized vesicles on an erythematous base
Locations: mouth, genitals, non-muocsal (cutaneous) areas ie hands, buttocks
Resembles shingles but shingle lesions are of varying sizes
What characterizes a primary HSV-1 infection?
Incubation - 6 days
Vesicles - wide area
Fever
Lymphadenopathy
Resolve in 2-3 weeks
What characterizes a recurrent HSV-1 infection?
Prodrome - itching, pain
Vesicles - grouped, localized
Resolves in 5 - 10 days
NO fever or lymphadenopathy
What does this patient have?
how can you tell?
Primary HSV-1 infection
Vesicles are present over a wide area - group of UNIFORM-sized umbilicated vesicles on an erythematous based
What does this patient have?
how can you tell?
Recurrent HSV-1 infection
Vesicles are present over a smaller area
What did this little girl develop?
Why did she develop it?
What is the culprit?
Eczema herpeticum
she has atopic dermatitis and acquierd a herpes virus (likely through her infected mom giving her a kiss)
What patients are at risk of HSV?
1) Neonates - can get infected during the birthing process through the birthing canal of an infected mother; if its not treated it can disseminate or cause CNS infection, resulting in mortality
2) HIV patients - develp a severe and prolonged primary + recurrent disease with increased risk of dissemination; may develop chronic ulcerative disease
3) atopic dermatitis - develops Eczema herpeticum
4) Hodgkins Lymphoma
5) Prednisone
“HAN”
What characterizes a Primary HSV-2 infection?
- Scattered vesicles
- Macerated under foreskin and vagina to form ulcers
What characterizes a recurrent HSV-2 infection?
1) Prodrome - itch, pain
2) Grouped Vesicles
Hoe comes in and says, DOC what do I have?
How do you tell what she has?
Primary HSV-2 infection
scattered lesions + presence of ulcers
You’re about to have sex with a hot guy, and he whips out his cock. You take one look at his junk and you say,
“dude, get away from me. You have an _______ infection!”
How do you tell?
Recurrent HSV-2 infection
presence of Grouped Vesicles
Patient comes in with this painful rash on her abdomen. What is it?
How do you know?
What is the time course of this diease?
What are the complications of this?
Shingles (caused by varicella zoster)
characterized by group of umbilicated vesciles on an erythematous base that appears on a dermatomal space; uniateral.
vesicles becomes hemorrhagic, pustular, and cruss over in 2-3 weeks
complications: peristant neuralgia, genearlized disseminated zoster
What is this patient’s diagnosis?
Shingles (reactivation of herpes Zoster virus over a dermatomal space)
usually happens over a single dermatome, but sometimes, as in this case, it can reactive over a few dermatomes
Diagnosis, please
Shingles. note the group of cutaneous vesicles that appears on an erythematous base over a unilateral dermatomal space
