Viral Infections of Skin Flashcards
What causes Chickenpox?
Varicella zoster or HHV-3
What are the two main infections of varicella?
Chickenpox (primary)
Shingles herpes zoster (recurrent)
What are the main symtpoms of chickenpox?
fever
headache
malaise
dry cough
sore throat
rash
What season does chickenpox like?
winter and early spring
Incubation period for chicky?
14-16 days
Features of rash of CP?
Macule then papule then vesicle then pustule then crusted papule and finally a scar
D/D of rash
Impetigo
Other viral infection
Insect bites
Contact dermatitis
Dx of chickenpox?
Clinical
Tzank smear
Immunofluorescence
PCR
Culture
Histopathology
Complications of chickenpox?
Gangrene
Thrombocytopenic purpura
Pneumonia
Encephalitis
Arthritis
SJS
Hepatitis
Tx of chickenpox?
Children no tx
Adults - oral acyclovir 800 mg 5 times for 7 days
If complicated case then 10 mg/kg/IV every 8 hours for 7 days
Pregnancy - same as adults
What is the preexposure prophylaxis for chickenpox?
Varicella live vaccine given 2 doses
if <13 years given with MMR
if >13 years 2 doses 4-8 weeks apart
What is the postexposure prophylaxis for chickenpox?
VZIG
Vaccine
Oral Antivirals
Herpes zoster is also called?
Shingles
Causative agent in HZ?
Reactivation of varicella zoster
Characteristics of HZ?
Dermatomal distribution (T1-L2 or CN V1)
Vesicle - pustule (3rd day) - dry crust (7-10 days)
Why does reactivation of varicella zoster occur?
Aging
Immunosuppression
Trauma
Surgery
Stress
What is post herpetic neuralgia?
Pain after resolution of rash of 1 month
Tx of Shingles
Analgesics
Antiviral
in more than 50 years
It also decreases the risk of PHN
Prevention of shingles
Zostavax if more than >60 years
It reduces the risk of infection and PHN
Complications of Shingles
Cutaneous
Visceral
Neurological
Cutaneous complications of Shingles?
Bacterial superinfection
Scarring
Zoster gangrenosum
Cutaneous dissemination
Visceral complications of Shingles
Hepatitis
Cystitis
Pneumonia
Arthritis
Esophagitis
Gastritis
Pericarditis
Neurological complications of shingles
Post herpetic neuralgia
Deafness
Transverse myelitis
Meningoencephalitis
Nerve palsies
Sensory loss
Ocular complications
Granulomatous angitis causing hemiparesis
Herpes simplex virus have two types
HSV-I for oral and facial lesions
HSV-II for genital and rectal lesions
HSV-1 lives in?
CN V
HSV-2 lives in?
S2-S5
Reactivation of HSV can occur due to
fever
trauma
stress
surgery
menses
Tx of HSV
Self limiting
Acyclovir 200mg 5x per day
Famicyclovir
Valacyclovir
What causes warts?
HPV (6 and 11)
How do warts spread?
skin to skin
shaving
Types of warts
Plantar warts
Plane warts
Filiform warts
Common warts
What does a wart look like?
brownish papule with rough surfaces
cauliflower shaped
What is pseudo koebner phenomenon?
IDK
Tx of warts
Electrocautery
Crytherapy
Topical Imiquimod
Ablative laser
Surgery
Podophylin
HPV benign or little malignant potential
HPV 6 and 11
HPV risk of CA
16, 18, 33 and 35
Complications of HPV
C section
Recurrent infections
Precancerous SCC
Fetus can catch it
Vaccination of HPV
9 valent HPV (6, 11, 16, 18, 31, 33, 45, 52 and 58)
Gardassi 9 (9vHPV)
Molluscum contagiosum is caused by?
Pox virus
How does molluscum contagiosum spread?
Skin to skin
Towels
Scratching
Shaving
STD
Features of molluscum contagiousum
Umbilicated waxy shinny looking papule that upon rupture emits cheesy material
Tx of molluscum contagiosu,
Self-limiting
Cryotherapy
Curettage
Laser
Imiquimod
