DERM: Intro to Maculopapular Rash I & II Flashcards
define “viral exanthem”
widspread maculopapular rashes that are accompanied by systemic sx of inflammation
what are the childood infections that cause viral exanthems?
which enteroviruses cause exthanthems?
- Cocksackie A
- echovirus
which childhood viral infection causes nonspecific exanthems?
what does this mean?
- echovirus 9
- echovirus 16
(enteroviruses)
= means there are no vesicles
enterovirus exanthem - pathogenesis
start in the GI tract -> progress to rest of body
enterovirus exanthem - presentation
cocksackie A, echovirus
- systemic
- prodrome
- major: GI sx PRECEDES development of rash
- possible respiratory tract sx
- skin: rash that is
- follows GI sx
- mild macular / maculopapular
- non-pruritic
- 1-3 days (fleeting)
enterovirus exanthem - epidemiology
- demographics
- transmissions
- means of spread
- other
- mostly young infants
- transmitted by saliva & feces (fecal oral)
- spread: _multiple family member_s may be infected concurrently
- most common childhood rash in the summer / fall
enterovirus exanthem - complications
rarely, to meningitis / encephalitis (HA)
parvovirus B12 exanthem - pathogenesis
(erythema infectiosum
virus infects erythroid progenitor cells -> leading to anemia
parvorirus B19 exanthem - presentation
erythema infectiosum
differ in child vs adult:
- child:
- systemic: nonspecific
- skin: “slapped check rash”
- starts on cheek - typically as child is feeling better
- +/- pruritis
- lasts 1-3 weeks
- often waxes / wanes (relapses)
-
adult
- systemic: acute polyarthritic sx common
- skin: rash rare
parvovirus B12 exanthem - epidemiology
- demographics
- transmission
- infectivity
- other
erythema infectiosum
- m/c in school age children
- transmitted via nasal/salivary droplets
- can cross placenta & rarely cause anemia (TORCH dz)
parvovirus B12 exanthem - complications
- acute asplastic crisis (adults) severe aplastic anemia that can laed to CHF, bone marrow necrosis, ect.
-
neonatal erythema infectiosum (neonates only)
- asplastic anemia
- hydrops fetalis
rubella exanthem - pathogenesis
german / 3 day measles
virus replicates in the URT/cerivcal lymph nodes then disseminates -> creates virus-Ab complexes in skin
rubella exanthem - presentation
german measles, 3 day rash
- systemic
- prodrome ONLY in adults, precedes rash
- polyarthritis in 50% of women
- forcheimer spots: petechial hemorrhage on soft palate
- rash
- non-confluent - widely spaced, discrete lesions
- starts on face -> descends (& fades on face)
- lasts up to 3 days
rubella exanthem - epidemiology
- demographics
- transmission
- infectivity
- other
- all ages affected
- transmitted by droplet inhalation
- can cross placenta (TORCH dz)
- rare in US d/t vaccine
rubella - complications
= congenital rubella syndrome (CRS)
-
classic triad: deafness + eye issues + CDH
- deafness
- eye abnormalities - cataracts, glaucoma, retinopathy
- congenital heart disease (“blue baby)
- blueberry muffin rash (purpura)
- growth restriction - low birth weight / microcephaly
- CNS abnormalities - retardation, behavioral disorders
describe the presentation of CRS
- classic triad: deafness + eye issues + CDH
- blueberry muffin rash (purpura)
- growth restriction - low birth weight / microcephaly / radiolucent bone dz
- CNS abnormalities - retardation, behavioral disorders
measles exanthem - pathogenesis
rubeola
paramyxovirus infects leukocytes/lymphatic tissue -> producing multinucleated giant cells (warthin-finkeldey cells) in lymph nodes
identify
warthin-finkeldey cells
mutli-nucleated giant cells resulting from paramyxovirus-infected leukocytes / lymphatic tissue
measles exanthem - presentation
- systemic: prodrome =
- photophobia
- koplik’s spots: white lesions of buccal mucosa opp. molars
- C-triad: cough + coryza + conjuncitivits
- HA
- otitis media (infants)
-
skin: rash
- onset follows fever but overlaps with it
- starts at hairline & descends slowly
- mildly pruritic
- petichial lesions on mucosa
measles exanthem - epidemiology
- demographics
- transmisision
- infectivity
- other
- n/a
- direct contact / droplets / fomites
- highly contagious
- generally rare in US due to vaccine
what are these and what exanthem are they indicative of?
koplik’s spots
measles (rubeola)
measles exanthem - complications
several - pneumonia is key (m/c cause of death d/t measles)
measles
- prognosis
- therapy
- prevention
- prognosis - inc mortality d/t complications (pneumonia m/c). complications indicator = inc risk of complications w/ fever persistence after the 4th day of the rash \
- therapy
- vitamin A
- ribavirin
- prevention - MMR vaccine
rosaela infantum exanthem - pathology
HHV-6 results in antibody-antigen complex formation -> rash
roseola infantum exanthom - pathologenesis
HHV-6B (sometimes HHV-7) causes antibody-antigen complex formation -> rash
roseola infantum - presentation
- systemic: sudden high fever then rapid defervescence followed by a surprise rash
- in infants: cause cause febrile seizures
- skin:
- a “surprise rash” that
- follows rapid defervescence (decline in fever with no overlap)
- is maculopapular
- along with Nagayama spots: small, erythematous papules on the soft palate (uvula)
- a “surprise rash” that
roseola infantum exanthem - epidemiology
- demographics
- transmission
- infectivity
- other
- kids 6 mos - 2 years (infants)
- transmission via:
- saliva
- genetic: integration of HHV-6 intoparent chromosome (congenital “roseola”)
roseola infantum exthanthem
- diagnosis
- prognosis
- therapy
- diagnosis: presentation usually sufficient
- prognosis: typically self limiting, febrile seizures in infants can inc morbidity
- therapy: avoidance, no vax
scarlet fever exanthem - pathology
streptococcus pyogenes express pyrogenic (fever causing) exotoxins A, B and C -> induces a type IV hypersensitivity reaction
scarlett fever exanthem - presentation
s. pyrogenes
- systemic prodrome
- abrupt onset of sore throat + fever
- sore throat = pharyngitis / tonsillitis
- but, no other upper respiratory signs
- tongue: either
- STRAWBERRY TONGUE - bright red
- WHITE STRAWBERRY TONGUE - yellowish white coating
- abrupt onset of sore throat + fever
- skin: sandpaper rash + pastia’s lines + circumoral pallor + superfiial desquamation
-
sandpaper rash - confluent, punctate papules that
- blanch under pressure
-
are concentrated in
- neck
- axilla
- groin
- pastia’s lines - peteiae in creases
- circumoral pallor (red cheeks + pale around mouth)
- superficial desquamation of palms & soles
-
sandpaper rash - confluent, punctate papules that