Inflammation and Infection Flashcards
1
Q
Most common bacterial infection in children?
A
impetigo
2
Q
how is impetigo usually contracted?
A
person to person
less commonly through fomites
3
Q
predisposing factors to impetigo?
A
high humidity
cutaneous carriage
poor hygiene
4
Q
causative agent
non bullous impetigo of childhood?
A
Streptococcus pyogenes
5
Q
causative agent
non-bullous and bullous impetigo (most common cause of both types of impetigo)
A
Staphylococcus aureus
6
Q
70-80% of all impetigo is which kind?
A
non-bullous impetigo
7
Q
non-bullous impetigo
most commonly affects?
A
face followed by extremities
8
Q
non-bullous impetigo - typical beginnings?
A
typically begins as single lesion - autoinoculation frequently produces multiple adjacent lesions
9
Q
non-bullous impetigo - early primary lesion – appearance?
A
erythematous macule with superficial blister (rarely appreciated)
10
Q
non bullous impetgio - developed lesion?
A
honey colored yellow crust
11
Q
do we see lymphadenopathy in non-bullous impetigo?
A
mild / variably present
12
Q
complication to have on your radar with non-bullous impetigo from streptococcal ?
A
up to 5% are associated with post-streptococcal glomerulonephritis
13
Q
bullous impetigo (percent)
A
20-30
14
Q
bullous impetigo body area
A
any area
15
Q
Bullous impetigo beginning?
A
typically begins as single lesion - autoinocculation frequently produces multiple adjacent lesion
16
Q
bullous impetigo - primary lesion
A
superficial, flaccid blister that may occasionally demonstrate layered pus
17
Q
bullous impetigo - older lesion
A
demonstrate collapsed blister that are often described as having a varnished like appearance
18
Q
Stapphylococcal scalded skin syndrome/
A
primarily seen in children less than six - produced by pahge group II strains that produce exoliative toxins - that produce diffuse superficial blisters over large areas of the body
listed under bullous impetigo
19
Q
Diagnosis of impetigo?
A
clinical
culture
biopsy (Rarely done)
20
Q
Impetigo with short chains of gram positive cocci amongst numerous neutrophils?
A
S pygogenes =
non-bullous impetigo of children
21
Q
treatment of impetigo?
A
soak and remove crust
topical antibiotics (limited cases)
systemic antibiotics
22
Q
topical antibiotic used to treat impetigo?
A
mupirocin 2% ointment
23
Q
do systemic antibiotics used to treat impetigo alter post-streptococcal glomerulonephritis risk?
A
no
24
Q
common systemic antibiotics
A
cephalexin
dicloxacillin
azithromycin
clarithromycin
25
impetigo fucks with what layer of skin
epidermis
26
cellulitis fucks with which layer of skin
dermis
27
epidemiology of cellulitis
more common in very young, elderly, immunocompromised, IV drug users, chronic ulcers
post-surgical
increased summer
28
where do celluitis infections occur through?
breaks in skin - breaks can be microscopic and not clinically noticeable
29
bacteriology of cellulitis
| most commonly associated with (3)
b-hemolytic streptococci (streptococcus pyogenes), staphylococcus aureus, Haemophilus influenza (kids)
30
What is erysipelas
clinical variant of celluitis in children -
31
eryspielas - most common bacteriology
b-hemolytic streptococci (streptococcus pyogenes)
32
What is erysipelas?
St. Elmo's fire
| Cellulitis
33
Erysipelas common presentation?
most commonly confined to face, less commonly extremities
34
erysipelas incubation period
2-5 days
35
erysipelas systemic symptoms
variable
| chills, fevers, malaise
36
erysipelas - primary lesion
sharply demarcated area of erythema (cliff drop border) that demonstrates non-pitting edema (lesions are often painful)
37
erysipelas - lymphadenopathy?
regional
| strictly present
38
erysipelas infrequent epidermal presentation?
rarely the overlying epidermis may demonstrate bullae, pustules, or hemorrhagic necrosis
39
cellulitis
| most common location
extremities
40
cellulitis
| incubation period
2-5 days
41
cellulitis
| primary lesion
ill defined non-palpable or subtly palpable area of painful erythema that is warm to the touch
42
cellulitis
| older lesion
may demonstrate variable hemorrhage
43
cellulitis
| lymph involvement?
lymphatic streaking commonly present
| regional lymphadenopathy frequently present
44
cellulitis
| patients may progress to?
septicemia
45
cellulitis
| diagnosis?
```
clinical
CBC may demonstrate luekocytosis
biopsy - may be conistent though organisms are rarely IDd
Culture more specific (use leading edge)
blood culture - positive in up to 10%
```
46
treatment of cellulitis?
correct against?
mild
severe
streptococcal or staphylococcal organisms
mild cases
- oral cephalexin
- oral dicloxacillin
- oral clarithromycin
- oral azithromycin
- oral fluoquinolone antibiotic
```
severe cases (require hospitalization)
- intravenous antibiotics with broad spectrum coverage (e.g. piperacillin/tazobactam or metronidazole plus ciprofloxacin)
```
47
true or false
| severe cases of cellulitis require hospitalization
true
48
dermatophyte infection
| -
superficial fungal infection - because dermatophytes eat keratin
49
dermatophyte infection acquired?
human
animal
fomite
soil
50
dermatophyte food source
keratin (top layer of skin / hair / nails)
51
socks and jocks dermatophyte?
epidermophyton - tinea cruris
52
most common dermatophyte?
trichophyton - tinea capitis / corporus
53
fluorescent dermatophyte in tinea capitis?
microsporum
54
most common cutaneous dermatophyte
trichophyton rubrun
55
most common tinea pedis
trichophyton metagrophytes
56
most common tinea capitis
trichophyton tonsurans
57
most common fluorescent tinea capitis
microsporum canis
58
most common tinea cruris
epidermophyton floccosum
59
dermatophyte infection of the scalp hair?
tinea capitis
60
dermatophyte infection of the scalp hair - variant with abscess formaiton
kerion
61
dermatophyte infection of the face
tinea faciei
62
dermatophyte infection of the beard
tinea barbae
63
dermatophyte infection of the glabrous skin (hair bearing)
tinea corporis
64
dermatophyte infection of the glabrous skin - variant characterized by follicular pustules and granulomas
majocchi's granuloma
65
dermatophyte infection of the genital region
tinea cruris
66
dermatophyte infection of the hands
tinea manuum
67
dermatophyte infection of teh feet
tinea pedis
68
dermatophyte infection of the nail
onychomycosis
69
how to diagnose dermatophyte infection
clinical
Potassium hydroxide (KOH) - organisms appear as hypahe or as athrospores
Culture on DTM
Biopsy with GMS stain
70
Treatment of dermatophyte infection?
topical antifungal agents
| systemic antifungal agents
71
do we use topical antifungals on nails?
not usually
72
common topical antifungals
imidazoles
allylamines
hydroxypyridones
73
common systemic antfungal agents
griseofulvin (tinea capitis)
fluconazole
itraconazole
terbinafine (tinea uniquium)
74
Candidiasis - what do they eat
glucose - so deeper in skin
75
candidiasis effects what?
mucous membranes and skin
76
candidiasis infections are more common in which populations (4)
diabetes
occlusion
corticosteroid users
broad spectrum antibiotics
77
which species is most common cause of candidiasis?
candida albicans - found as normal microflor in the GI tract of greater than 80% of individuals
78
oral candidiasis =
thrush
79
angular cheilitis =
candida infection
| perleche
80
diaper dermatitis
erosio interdigitalis
two common types of?
cutaneous candidiasis
81
candida infection of v
vulvovaginitis
82
balanitis
glans penis candida
83
rare candida variant characterized by absence of normal immunity
chronic mucoctaneous candidiasis
84
dx of candidiasis
clinical presentation
KOH - pseudohyphae - fatter than dermatopytes and less branches / septate
culture - (saboraud's agar / nickerson's medium) --> looks like mucoid white substance
biopsy
85
treatment of candidiasis
topical antifungals - not usually on nails
| systemic antifungals
86
systemic antifungal (candida) treatment of choice for mucosal disease?
fluconazole
87
Tinea (Pityriasis) Versicolor
fungal infection
88
Tinea (Pityriasis) Versicolor
distribution
increased incidence
demographic
worldwide distribution
more common in humid and warm climates
confined to post-pubertal
89
Tinea (Pityriasis) Versicolor
| food?
follicular lipids
90
Tinea (Pityriasis) Versicolor
| mycology
Malassezia furfur
| Pityrosporum oribulare
91
Tinea (Pityriasis) Versicolor
| cutaneous distribution
primarily truncal
92
Tinea (Pityriasis) Versicolor
| primary lesion
asymptomatic - tan colored / subtle scaly macules that may develop into large patches
93
Tinea (Pityriasis) Versicolor
| hypopigmented variant?
due to production of azelaic acid that inhibts the function of tyrosinase produced by melanocytes
94
Tinea (Pityriasis) Versicolor
| pityrosporum folliculitis variant?
characterized by follicular papules in pustules on the trunk, arms, and occasionally face
95
Tinea (Pityriasis) Versicolor
| diagnosis
clinical
| KOH - spaghettic and meatballs hyphae /yeast
96
Tinea (Pityriasis) Versicolor
| treatment
selenium sulfide shampoo applied topically
topical imidazoles
oral itraconazole / ketoconazole
97
Scabies
| epidemiology
everyone
higher prevelance in sexually active
spread is primairly person to person rarely fomites
98
scabies
| parasitology
sarcoptes scabiei - hominis
| i.e. only humans
99
scabies life cycle
30 days in epidermis before the female lays 60 to 90 eggs that mature in 10 days
100
scabies size
0.35mm
101
scabies #
usually less than 100
102
scabies
| clinical distribution
symmetric with characteristic areas of involvement being the interdigital webspace of the hands, flexural portion of the wrist, waist, around the axillary araes, genitalia, and butt
103
scabies typically spares (body parts)
head
palms
soles
104
scabies - symptoms accentuated ?
at night or by hot baths and showers
105
scabies
| primary lesion?
erythematous papules
wavy threadlike grayish white to slightly erythematous burrows - pathognomonic finding
distinctive erythematous nodules on male genitalia
106
scabies secondary lesion
excoriations and secondary infections
107
norwegian scabies?
crusted scabies - extenisve infestations associated with massive hyperkeratosis - typically seen in immunocompromised individuals and patients with diminished sensory function
108
scabies
| dx - clinical
id of characteristic burrows or genital nodules
109
scabies dx
| mineral oil?
small drop of mineral oils is placed on the skin in gently scraped and examined under microscope for infestation evidence --> mite / egg / skybala
110
scabies dx
| skin biopsy
occasionally needed - can be diagnostic if mites, eggs, or feces are id'd on epidermis
111
scabies
| treatment cream?
permethrin 5% cream - treamtent of choice in most cases (tolerance but not true resistance has been seen in some strains)
112
scabies
| treatment lotion?
lindane 1% - use limited by increasing resistance
113
scabies
| treatment of choice in extensive cases or cases that fail topica?
ivermectin
114
lice
| epidemiology
worldwide
| 12 million / yr in US (head)
115
Crab lice
| epidemiology
highest in homosexual males and men 15-40
116
Lice parasitology
| scalp infector?
pediculus humanus var. capitis - bloodsucking, wingless insect that preferentially infects scalp
117
Lice parasitology
| trunk infector?
pediculus humanus - var corpus
| most common in indigent
118
Lice parasitology
| genital infector?
phthirus pubis
119
Head lice
| area?
limited to scalp with the area behind the ears in teh nape of the neck being the area most commonly affected
120
Head lice
| symptoms
pruritus
121
Head lice
| skin presentation?
erythema, scale, and secondary infection commonly present
122
head lice
| what they look like?
nit are tan-brown oval eggs attached to hair shafts (Relatively easy to find) once the eggs hatch they are white in color
lice demonstrate a brown-tan color with 6 legs and are more difficult to find
123
body lice
| look like and local
lice and eggs are morphologically identical to head lice but are found only on clothes except during feeding
124
body lice
| clinical findings
intense pruritus
| erythematous papules and macules that are most commonly located on the trunk
125
crab lice
| local?
limited to the hair of the genital area and less commonly eyelashes, beard, or axilla
126
crab lice
| symptoms
pruritus of genitals
127
crab lice
| appearance
nits are usually similar to those in head lice, the adult louse is usually easily found attached to base of hairs
128
crab lice
| dx?
clinical presentation
| demonstration of either nit or louse
129
treatment
| head lice
```
pyrethrin (otc)
permethrin 1% cream rinse (otc)
lindane 1% shampp
malathion 0.5% - most efficacious
ivermectin - very good efficacy
```
130
body lice
| treatment
deinfestation of clothing and bedding by fumigation / heating to 65C
topical treatments that are effective against scabies are also used
131
crab lice
| treatment
permethrn
pyrethrin
lindane 1% shampoo
ivermectin
132
what should dandruff in a school age child tip you off to?
ring worm (tinea capitis)
we do not normally see dandruff in school age children so you should be considering tinea capitis (dermatophyte) - ring worm - with central clearing
133
bacterial skin diseases (2 types we went over)
impetigo - surface
cellulitis - deeper
134
impetigo contagiosa =
streptococcal non-bullous impetigo
| most commonly children face
135
post-streptococcal glomerulonephritis - worry about with
streptococcal non-bullous impetigo - (impetigo contagiosa)
136
impetigo with gram stain demonstrating short chains of gram-positive cocci amongst numerous neutrophils - think?
Strep pyogenes
137
impetigo with biopsy showing clusters of bacteria inside blister cavity - think?
staphylococcus bullous impetigo
138
cliff drop border facial reddening - clue you to?
| could also look for ___ as clinical pearl
erysipelas = facial cellulitis (strep)
lymphadenopathy - preauricular
139
fungal infections of the skin (2) surface and deep
dermatophyte - eat keratin
candidiasis - eat glucose
140
variant of tinea corporis characterized by follicular pustules and granulomas
majocchi's granuloma
141
long hollow septate branching hyphae on KOH?
Dermatophyte
142
if your test medium changes color from amber to red this is positive sign of ?
dermatophyte infection
143
tinea pedis
| topical treatment with
naftifine
