DERM: Intro to Maculopapular Rash I & II Flashcards
1
Q
define “viral exanthem”
A
widspread maculopapular rashes that are accompanied by systemic sx of inflammation
2
Q
what are the childood infections that cause viral exanthems?
A
3
Q
which enteroviruses cause exthanthems?
A
- Cocksackie A
- echovirus
4
Q
which childhood viral infection causes nonspecific exanthems?
what does this mean?
A
- echovirus 9
- echovirus 16
(enteroviruses)
= means there are no vesicles
5
Q
enterovirus exanthem - pathogenesis
A
start in the GI tract -> progress to rest of body
6
Q
enterovirus exanthem - presentation
A
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)
7
Q
enterovirus exanthem - epidemiology
- demographics
- transmissions
- means of spread
- other
A
- 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
8
Q
enterovirus exanthem - complications
A
rarely, to meningitis / encephalitis (HA)
9
Q
parvovirus B12 exanthem - pathogenesis
A
(erythema infectiosum
virus infects erythroid progenitor cells -> leading to anemia
10
Q
parvorirus B19 exanthem - presentation
A
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
11
Q
parvovirus B12 exanthem - epidemiology
- demographics
- transmission
- infectivity
- other
A
erythema infectiosum
- m/c in school age children
- transmitted via nasal/salivary droplets
- can cross placenta & rarely cause anemia (TORCH dz)
12
Q
parvovirus B12 exanthem - complications
A
- 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
13
Q
rubella exanthem - pathogenesis
A
german / 3 day measles
virus replicates in the URT/cerivcal lymph nodes then disseminates -> creates virus-Ab complexes in skin
14
Q
rubella exanthem - presentation
A
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
15
Q
rubella exanthem - epidemiology
- demographics
- transmission
- infectivity
- other
A
- all ages affected
- transmitted by droplet inhalation
- can cross placenta (TORCH dz)
- rare in US d/t vaccine
16
Q
rubella - complications
A
= 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
17
Q
describe the presentation of CRS
A
- classic triad: deafness + eye issues + CDH
- blueberry muffin rash (purpura)
- growth restriction - low birth weight / microcephaly / radiolucent bone dz
- CNS abnormalities - retardation, behavioral disorders
18
Q
measles exanthem - pathogenesis
A
rubeola
paramyxovirus infects leukocytes/lymphatic tissue -> producing multinucleated giant cells (warthin-finkeldey cells) in lymph nodes
19
Q
identify
A
warthin-finkeldey cells
mutli-nucleated giant cells resulting from paramyxovirus-infected leukocytes / lymphatic tissue
20
Q
measles exanthem - presentation
A
- 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
21
Q
measles exanthem - epidemiology
- demographics
- transmisision
- infectivity
- other
A
- n/a
- direct contact / droplets / fomites
- highly contagious
- generally rare in US due to vaccine
22
Q
what are these and what exanthem are they indicative of?
A
koplik’s spots
measles (rubeola)
23
Q
measles exanthem - complications
A
several - pneumonia is key (m/c cause of death d/t measles)
24
Q
measles
- prognosis
- therapy
- prevention
A
- 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
25
rosaela infantum exanthem - pathology
HHV-6 results in antibody-antigen complex formation -\> rash
26
roseola infantum exanthom - pathologenesis
**HHV-6B** (sometimes HHV-7) causes antibody-antigen complex formation -\> rash
27
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)
28
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")
29
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
30
scarlet fever exanthem - pathology
***streptococcus pyogenes*** express _pyrogenic_ (fever causing) **exotoxins A, B and C -\>** induces a type IV hypersensitivity reaction
31
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
* skin: sandpaper rash + pastia's lines + circumoral pallor + superfiial desquamation
1. **sandpaper rash -** confluent, punctate papules that
* **blanch under pressure**
* **are concentrated in**
* neck
* axilla
* groin
2. **pastia's lines - peteiae in creases**
3. **circumoral pallor (red cheeks + pale around mouth)**
4. **superficial desquamation of palms & soles**
32
scarlet fever exanthem - complications
= s. pyogenes
* rheumatic fever (type II hypersensitivity)
* glomerulonephritis (type III hypersensitivity)
33
tx of scarlett fever?
penicillin G
34
identify this feature & explain its significance
pastia's lines: petichiae in creases
seen in scarlett fever exanthem (s. pyogenes)
35
what childhood viral exanthem do these signs indicate?
scarlett fever
* strawberry & white strawberry tongue = systemic
* desquamation of palms = skin
36
which childhood viral exanthems are nationally notifiable disease?
* rubella (rubella virus)
* measles (paramyxovirus)
37
which childhood viral exanthems are TORCH disease?
* erythema infectiosum (parvovirus B19)
* rubella
38
differentiate the key differences between the _skin presentations_ of each childhood viral exanthem
* erythema infectiosum (parvovirus B19)
* **slapped cheeks**
* **reticulate (lacy) body rash**
* enterovirus rash: descenending from _face_ down
* rubella (german / 3-days measles): descending from _face_ down
* measles:
* **kopliks spots**
* descending rash from **_harline_** down
* goes from _blanching -\> non-blanching_
* roseola infantum
* _"surprise rash" (on trunk)_ **following rapid defervescence**
* scarlett fever
* **sand-paper rash** (punctate, confluent papules) on neck + axilla + groin
* **circumforal pallor**
* **pastias lines**
* **post-rash desquamation on palms & sole**s
39
which childhood viral exanthem can cause _postauricular lymph node_ enlargement?
rubella
40
which childhood viral exanthem is the most common infection of summer / fall?
enteroviruses (cocksackie A and B)
41
which childhood viral exanthems involve no / short prodrome ?
* erythema infectiosum (parvovirus B12)
* enteroviruses
* rubella
EER - extra extra rapid
42
43
tinea versicolor - pathogenesis
= pityriasis versicolor (cutaneous malsseziasis)
* ***malassezia sp*** (a dimorphic fungi) metabolize lipids to _generate acids_ **that can damage melanocytes** causing -\> **hyperpigmented or hypopigmented** lesions
44
tinea versicolor presentation
*malasseziasis sp*
* skin: lesions on _upper trunk_ that are
* HYPOPIGEMENTED (white-ish) or HYPERPIGMENTED (brown)
* "**branny" - scaly, non-blanching**
45
tinea versicolor - diagnosis
* 10% KOH treated scin scraping: **"spaghetti & meatball appearance"**
* wood's lamp: shows **yellow/orange luminescence**
46
tinea versicolor - summary
* pathogenesis
* demographics
* presentation
* treatment
* pathogenesis ***malassezia sp*** (a dimorphic fungi) metabolize lipids to generate acids that can _damage melanocytes_
* demographics
* m/c in **tropical environments**
* repeated overgrowth in - oily skin or I/C
* presentation: HYPOPIGEMENTED (white-ish) or HYPERPIGMENTED (brown) lesions that are scaly & non-blanching
* treatment: anti-fungals
47
identify
spaghetti & meatbals appearance from KOH stain
dx of tinea versicolor (malasezzia sp fungi)
48
tinea versicolor - demographics
* m/c in tropical environments
* repeated overgrowth is m/c in people with
* oil skin
* weak immune system
49
tinea versicolor - tx
topical anti-fungals
50
toxic shock syndrome (TSS) - pathogenesis
* infection w/ **s. aureus \> strep pyogenes**, which release **pyogenic superantigens** that act as T-cell mitogens -\> cytokine strom -\> high fever
* s. aureus: **TSST-1 & enterotoxins** (enterotoxin = also cause GI sx)
* s. pyogenes: **exotoxins** & poss M-protein
51
toxic shock syndrome (TSS) - demographics
s. aureus \> s. pyogenes
* generally very rare in US
* though - is m/c in individuals that are _negative for anti-TSST-1 antibodies_ & are unable to make any after being exposed
52
toxic shock syndrome - presentation
s. aureus \> s. pyogenes
* systemic:
* **sudden, rapidly progressing fever that can progress to SHOCK:** _HYPOTENSION_ + tachycardia / tachypenea
* + GI sx if s. aureus
* skin :**erythyematous, macular ras**h + *elements* *resembling scarlett fever, esp if s. pyo*
* desquamation of palms & soles
* strawberry tongue
* if so pyo: sandpaper rash
53
toxic shock syndrome (TSS) - dx
s. aureus \> s. pyro
* must meet the following criteria to fit CDC definition:
1. fever of 102 F or greater
2. rash that is: macular & erythematous OR scarlittiniform (sandpaper)
3. HYPOtsn: SBP \< 90 or orthostatic drop in SBP \> 15 mmHg
4. at least 3 major organs involved
54
toxic shock syndrome (TSS) - treament
* abx: nacillin or oxicillin
* TREAT SHOCK
55
TSS - summary
* pathogenesis
* demographics
* presentation
* diagnosis
* treatment
* pathogenesis: infection w/ **s. aureus \> strep pyogenes**, which release **pyogenic superantigens** that act as T-cell mitogens -\> cytokine strom -\> high fever
* s. aureus: **TSST-1 & enterotoxins** (enterotoxin = also cause GI sx)
* s. pyogenes: **exotoxins** & poss M-protein
* demographics: generally very rare in US, but m/c in indiivduals _negative for anti-TSST-1 Abx_
* presentation:
* systemic:
* **sudden, rapidly progressing fever that can progress to SHOCK:** _HYPOTENSION_ + tachycardia / tachypenea
* + GI sx if s. aureus
* skin :**erythyematous, macular rash** + *elements* *resembling scarlett fever, esp if s. pyo*
* desquamation of palms & soles
* strawberry tongue
* if so pyo: sandpaper rash
* diagnosis: must meet the following criteria to fit CDC definition: 4
1. fever of 102 F or greater
2. rash that is: macular & erythematous OR scarlittiniform (sandpaper)
3. HYPOtsn: SBP \< 90 or orthostatic drop in SBP \> 15 mmHg
4. at least 3 major organs involved
* treatment: **nafcillin / oxicillin + TX shock**
56
meningococcemia - pathogenesis
***neisseria meningitidis*** _(gram - diplococci_) releases **lipooligosacharide (LOS) endotoxin,** leading to -\> vasculitis / localized thrombohemorrhaghic lesions
57
meningococcemia - demographics
* **infants**
* **teens**
* **complement deficient: C5, C6, C7 or C8**
58
leptospirosis
* pathogenesis
* trasmission
* presentation
* prognosis
* treatment
= aka weil's syndrome:
* pathogenesis: ***leptospirosis*** (**spirochete with hooked ends**) reside in kidneys & lead to vasculitis
* transmission: **exposure to urine / urine contaminated water** from **infected mammals**
* presentation:
* **macular rash -\> purpura**
* **weil's triad: JAUNDICE + ACUTE KIDNEY INJURY + HEMORRHAGE**
* **hemorrhage:**
* pulmonary hemorrhage
* subconjunctival hemorrhage
* epistaxis
* purpura
* prognosis:
* self limiting except in unborn fetus (\> 50% mortality)
* _better if there is NO juandice_
* treatment: Abx (prevention with doxycyline)
59
identify & explain significance
= leptospirosis:
* **spirochete with hooked ends**
* **contracted via contact w/ urine from infected mammals**
* causes:
* weil's triad: **jaundice + acute kidney injury + hemorrhage**
* hemorrhage =
* purpura
* subconjunctival hemorrhage
* pulmonary hemorrhage
* prognosis better when there is NO jaundice
60
meningococcemia - presentation
* systemic: nonspecific prodrome
* skin: non-blanchng macules & petichiae that
* begin on _trunk & legs_ then spreading to **_areas where pressure is applied_**
* can progress
* **purpura**
* **ecchymosis with central necrosis (confluent purpura)**
61
meningococcemia - complications
* septic shock
* meingitis
* disseminated itravascular coagulation (DIC)
* waterhouse-friedrichsen syndrome
62
meningococemia - treatment
* **penicillin G / ceftriaxone**: NECESSARY, OR IS FATAL
* **prevention with menACYW vaccine:** meningococcal conjugated polysaccharide vaccine
* note: booster & menB serotype given during epidemics
63
rat-bite fever
* pathogenesis
* presentation
* treatment
* d/t one of _two gram negative bacteria_ that cause hematogenous dissemination:
* streptobacillary:- **d/t *streptobacilus monoformis:***
* microaerophillic
* pleomorphic
* filamentous rod
* spirillary: **d/t** ***spirillum minus:***
* ******aerobic
* bipolar-flagellated spiral
* presentation:
* systemic:
* **polyarthralgia**
* **relapsing fever at _irregular_ intervals**
* skin: purpuric maculopapular rash -\> small pustules on palms & soles
* treatment: penicillin G
64
what are the two etiologic agents of rat-bite fever and
* how are they different?
* which one causes RBF in the US?
* streptobacillary (***streptobacilus monoformis) -* only form seen in the US**
* microaerophillic
* pleomorphic
* filamentous rod
* spirillary (***spirillum minus)***
* ******aerobic
* bipolar-flagellated
* spiral
65
secondary syphyllis
* pathogenesis
* transmission
* presentation
* diagnosis
* prognosis
* treatment
* pathogenesis: ***treponema pallidum*** (**spirochete**) causes a chancre at innoculation site
* transmission:
* sexually
* congenital (TORCH dz)
* presentation:
* **rash:**
* maculopapular lesions on the palms & soles are non-pruritic
* mucutaneous lesions ton oral, genital, anal
* **condyomata latum:** wart like, moist
* **alopecia**
* diagnosis:
* VDLR/RPR, then FTA-ABS
* darkfield microscopy - shows spirochete
* treatment: penicillin G
66
erlichiosis
* pathogenesis
* presentation
* diagnosis
* treatment
* pathogenesis: one of two _obligate intracellular_ pathogens is transmitted via _lone star tick bite_
* ***erlichiae chaffeensis:*** infects _monocytes_ - human form
* ***erlichiae ewingii:*** infects _granulocytes_
* presentation: same as anaplasmosis
* rash: **often NOT even seen\* - pinpoint maculopapular ("lacy") rash**
* systemic:
* prodrome - fever, chills
* **thrombocytopenia**
* **elevated liver enzymes**
* diagnosis: **morulae** - microbe within cytosplasmic vacules in phagocytic cells
* treatment: doxycycline
67
what are the two etiological agents for ehrlichiosis and how do they differ?
both obligate intracellular parasites carried by **lone star tick**
* ***erlichiae chaffeensis:*** infects _monocytes_ - human form
* ***erlichiae ewingii:*** infects _granulocytes_
68
which form of erlichiosis invades humans?
***erlichiae chaffeensis:*** infects _monocytes_ - human form
69
morulae
cytplasmic inclusions of erlichiosis / amaplasmosis in a phagocyte
(in this case, anaplasma in a granulocyte)
70
morulae
cytplasmic inclusions of erlichiosis / amaplasmosis in a phagocyte
(in this case, erlichiosis in a monocyte)
71
anaplasmosis
* pathogenesis
* presentation
* diagnosis
* treatment
* pathogenesis: anaplasma phagocytophilum - an _obligate intracellular_ pathogen - is transmitted via _ixodes tick_
* presentation: same as anaplasmosis
* rash: **often NOT even seen\* - pinpoint maculopapular ("lacy") rash**
* systemic:
* prodrome - fever, chills
* **thrombocytopenia**
* **elevated liver enzymes**
* diagnosis: **morulae** - microbe within cytosplasmic vacules in granulocytes
* treatment: doxycycline
72
rocky mountain spotted fever
* pathogenesis
* presentation
* diagnosis
* treatment
* pathogenesis: ***rickesttiae rickettsiae*** - a _obligate intracellular_ pathogen transmitted by _ixodid tick_ - infects vascular endothelial cells
* presentation:
* skin: **_ascending rash_ that starts from the _wrists & ankles_ and the moves _centripitally_ (outward -\> inward) within hours. is**
* non-pruritic
* involving the soles & palms
* systemic: significant involvement
* **muscle degeneration**
* **edema - _periorbital\*_ & _peripheral_ (pulmonary, cerebral)**
* **conjunctival suffusion\***
* **thrombocytopenia** (like anaplasma, erclichiosis)
* treatment: doxycyline
73
what presentations can rock mountain spotted fever have with respect to the _eye_?
* periorbital edema
* conjunctival suffusion
74
contrast the rashes caused by rickettsia (rocky mounted spotted fever & rickettsiapox) and erlichiosis / anaplasma ?
* RMSF (rickettsia, ixodids tick): **ascending / centripital rash** starting at **wrists & ankles**
* rickettialpox (rickettsia, mite): **initial eschar** + subsequent crop if vesiculopapules
* erlichiosis / asnplasma (lone star tick, ixodids tick): **often undetectible, punctate rash**
75
endemic typhus
* pathogenesis
* presentation
* diagnosis
* pathogenesis: infection via _obligate intracellular pathogen_ by carried by _lice_ from a _flying squirrel vector_
* presentation:
* systemic: **prolonged high fever (104 F for ~2 weeks)**
* rash: **begins in _axilla & trunk_ -\> spreads centrifugally and out to extremities**
* diagnosis: weil-felix test
76
flea-borne murine typhus
* pathogenesis
* demographics
* presentation
* pathogenesis: contraction of ***ricksettia typhi*** - an _obligate intracellular_ coccobacillus - _via fleas_ (from several animal reservoirs)
* demographics: **contact with animals - cats, mice, opposum**
* presentation:
* rash**: begins on the trunk - spreads centrigually to extremities (like endemic typhus)**
* systemic: classic prodrome
77
cutaneous tuberculosis
* pathogenesis
* presentation
* diagnosis
* pathogenesis. m tuberulosis (acid-fast aerobic bacillus) forms _caseating (necrotic) granulomas_
* can be triggered by BCG vaccination
* presentation: depends on if infection of primary or secondary:
* primary: enters skin via trauma sites
* no prior exposure to TB - \> papule / nodule ("innoculation chancre"
* rrior exposure to TB -\> warty lesions ("verrucosa cutis")
* secondary: patient with TB In lung that dissseminates
* **_tuburculoid granulomas_**
* **red-brown**
* **painless**
* **on the _head_ or the _neck_**
* diagnosis:
* **Mantoux test / IGRA test** (no false + from vax)
* **lesions beomes yellow-brown "apple jelly" upon application of pressure**
78
leprosy / hansen's disease
* pathogenesis
* presentation
* diagnosis
*
*
79
compare and contrast the etiological agents of
* cutaneous tuberulosis
* leprosy / hansen's disease
* both are acid fast aerobic bacillus
* m. tuberulosis:
* NOT an obligate intracellular pathogen
* growth NOT restricted at 37 C
* m. leprae is
* obligate intracellulate
* growoth restricted at 37 C
