Infectious Disease Flashcards
1
Q
empiric abx coverage: CAP
A
azithromycin (po)
ceftriaxone and azithromycin (IV)
OR
moxifloxacin (PO and IV)
2
Q
empiric abx coverage: HCAP
A
vancomycin and Pip/Tazo
OR
Linezolid/Meropenem
3
Q
empiric abx coverage: UTI
A
amoxicillin (1st line) nitrofurantoin (if PCN allergy) TMP-SMX (if no ckd) cipro (ambulatory pyelonephritis) ceftriaxone (pyelonephritis)
4
Q
empiric abx coverage: skin
A
MRSA: vancomiycin -> clinda
MSSA: nafcillin
strep: PCNs
5
Q
empiric abx coverage: GI
A
ciprofloxacin + metronidazole
OR
ampicillin, gentamycin, metronidazole
6
Q
empiric abx coverage: C. diff
A
mild: po vanc
severe: po vans + IV metronidazole
recurrent: po fidaxomicin
7
Q
principles of antibiotics test taking
A
convenience antibiotics are almost always wrong
- ceftriadxone, metronidazole
the stuff the ED always uses will be wrong
- ceftriaxone, vancomycin+pip/tazo
the test will give you a reason for why one of these can’t be used or give you an option that has alternates
8
Q
alternate for vanc
A
linezolid
9
Q
alternate for pip/tazo
A
meropenem, cefepime
10
Q
alternate for ceftriaxone
A
ceftazidime
11
Q
alternate for cipro
A
ampicillin-gentamycin
12
Q
HIV path
A
CXCR4 and CCR5 receptors
Gp120
RNA virus
reverse transcriptase
13
Q
HIV pt
A
opportunistic infections
acute retroviral syndrome (flu)
14
Q
HIV dx
A
3rd-gen ab test: if + -> western blot OR 4th gen ag-ab, confirmation built in THEN viral load and CD4 count
15
Q
HIV tx
A
2+1: 2 nucleoside reverse transcriptase-i AND 1 non-nucleoside reverse transcriptase-i OR 1 protease inhibitor/ritonavir OR 1 fusion inhibitor OR 1 integrase inhibitor
16
Q
HIV f/u
A
CD4 climbs 50/yr
viral load fall 1 log in 4wks
17
Q
ppx to exposure HIV
A
Pre-exposure ppx - emtricitabine + tenofovir Post-exposure ppx - emtricitabine + tenofovir +/- raltegravir pregnancy - AZT
18
Q
HIV opportunistic infections: PCP
A
CD4 < 200
TMP-SMX (1st line ppx)
dapsone (2nd line ppx)
atovaquone (G6PD, sulfa allergy)
19
Q
HIV opportunistic infections: toxo
A
CD4 < 100
TMP-SMX
20
Q
HIV opportunistic infections: MAC
A
CD4 < 50
azithromycin ppx
21
Q
HIV opportunistic infections: HHV-8
A
kaposi’s sarcoma
purple lesion anywhere on the skin
22
Q
HIV opportunistic infections: candida
A
oropharynx: nystatin swish & spit (no systemic therapy)
esophagus: fluconazole (systemic therapy for AIDS defining)
23
Q
TB path
A
acid fast bacillus
spread through cough
caveating granulomas
24
Q
TB pt
A
asx screen
OR
1st exposure = pneumonia = fever + cough
reactivation = fever, hemoptysis, weight loss, Gohn’s complex
25
TB risk
homeless
foreign travel
prsion
26
TB dx
```
asx screen (PPD or Interferon)
- PPD ... read at 48-72hrs
--5mm immunocompromised
--10mm health care workers
--15mm soccer moms
-γ-interferon
--positive or negative
cxr = cavitary lesions, granulomsa
AFB smears + isolation
```
27
TB tx
if AFB + = RIPE
if AFB - but cxr + = isoniazid + B6
if AFB - and cxr - = isoniazid + B6
28
TB f/u
ignore bcg vaccine (pick γ-interferon if asked to choose)
never PPD if ever the ppd is positive
if AFB +, but weeks later it turns out to be MAC, tx as MAC
29
RIPE therapy
Rifampin
Isoniazid (INH)
Pyrazinamide
Ethambutol
30
rifampin side effects
turns body fluids Red
31
Isoniazid (INH)
B6 deficiency, Neuropathy
| always give B6 ppx
32
Pyrazinamide
hyperuricemia
33
Ethambutol
eye, color vision disturbance
34
SIRS criteria
Temp > 38 or < 36
WBC >12 or <4
HR > 90
RR > 20
35
Severity: SIRS
2/4 SIRS criteria
36
severity: sepsis
SIRS + source of infection
37
severity: severe sepsis
sepsis + decrease BP/increase lactate
| responsive to volume
38
severity: septic shock
sepsis + decrease BP/increase lactate
unresponsive to volume
(unit, pressers)
39
early goal directed therapy for sepsis
CVP 8-12
MAP >65
U output >0.5cc/kg/hr
SvO2 >70%
40
actions for sepsis
```
antibiotics and fluids
pressors
lactate
oxygen
source control
```
41
who gets antibiotics and fluids with sepsis
everyone, within 6hrs
empiric abx
30cc/kg IVF bolus LR = NS
42
who gets pressors with sepsis
if in shock
1 = norepinephrine
2 = vasopressin
3 = steroids
43
lactate and sepsis
trend lactate for clearance
44
oxygen and sepsis
improve oxygen delivery to tissues
45
source control sepsis
remove plastic (lines, catheter) and drain abscesses
46
meningitis path
bacterial
47
meningitis pt
fever and headache
| stiff neck
48
meningitis dx
1st and best: LP
| shows many neutrophils
49
meningitis tx
ceftriaxone (everyone)
vancomycin (everyone)
steroids ("everyone")
ampicillin (immunocompromised)
50
meningitis f/u
syphilis: VDRL, RPR in CSF -> IV PCN
lyme: lyme Ab in CSF -> ceftriaxone
TB: AFB + -> RIPE
Cryptococcus => crypto antigen (not india ink) -> amphotericin
RMSF: RMSF antibody -> ceftriaxone
51
FAILS for meningitis
if FAILS: abx first, then CT, then LP
if NOT fails: LP first, then abx
```
Focal neurologic deficit
Altered mental status
Immunocompromised
Lesion over site of LP
Seizures
```
52
abscess/mass path
mass effect
53
abscess/mass pt
fever and headache
| focal neurologic deficit
54
abscess/mass dx
1st: CT scan w abx
if AIDS and toxo Ag+ -> treat toxo
- pyrimethamine-sulfadiazine and rescan
if NOT AIDS or NOT toxo Ag + -> biopsy
55
abscess/mass tx
```
abscess = abx
cancer = chemo and radiation
```
56
abscess/mass f/u
repeat CT for toxo
- shows improvement, continue
- if not, bx
57
encephalitis path
viral, infection of parenchyma
58
encephalitis pt
fever and headache
| AMS
59
encephalitis dx
1st: CT scan w abx
best: LP = lymphocytes
- get HSV PCR
60
encephalitis tx
herpes with acyclovir
61
encephalitis f/u
flaccid paralysis = west nile
| temporal lobe = herpes encephalitis
62
bronchitis path
a 'not that bad' pneumonia
63
bronchitis pt
fever and a cough
| sputum production
64
bronchitis dx
cxr = no consolidation (normal)
65
bronchitis tx
doxycycline, azithromycin
66
pneumonia path HCAP
dialysis, hospitalized, nursing home
| risk for MRSA and pseudomonas
67
pneumonia path CAP
no HCAP risk, usual bugs
| S. pneumo, M. catarrhalis, H. flu
68
pneumonia path other
klebsiella, think EtOH
mycoplasma, think cold agglutinin disease
staph aureus, think post-viral URI
AIDS, think PCP, TB, fungus, CMV
69
pneumonia pt
fever and cough
| consolidation physical = increase fremitus, increase egophany, decrease lung sounds, dullness
70
pneumonia dx
cxr = consolidation
| induced sputum, silver stain for PCP
71
pneumonia tx
HCAP: vancomycin, Pip/tazo
CAP: ceftriaxone, azithromycin, or moxifloxacin
72
pneumonia f/u
```
pneumonia vax (streptococcal)
legionella = get a urine antigen
```
73
PCP pneumonia path
HIV, AIDS, CD4 <200
74
PCP pneumonia pt
bilateral interstitial infiltrates
| subacute pneumonia
75
PCP pneumonia dx
silver stain on sputum
76
PCP pneumonia tx
Bactrim IV
| steroids if PaO2 < 70
77
PCP pneumonia f/u
clues are Increase LDH, but don't order it
78
abscess path
necrosis of the lung
79
abscess pt
fever and a cough
sputum production
foul breath
80
abscess dx
cxr = cavitation
81
abscess tx
abx (I&D if necessary)
82
asymptomatic bacteriuria pt
UA for 'screening' purposes and happens to be positive
83
asymptomatic bacteriuria tx
no tx unless pregnant
84
asymptomatic bacteriuria in pregnancy path
pregnant women
85
asymptomatic bacteriuria in pregnancy pt
asx screen for pregnant women
86
asymptomatic bacteriuria in pregnancy dx
urinalysis = leuk esterase and nitrates
| urine culture
87
asymptomatic bacteriuria in pregnancy tx
amoxicillin (first line)
| nitrofurantoin (if PCN allergy)
88
asymptomatic bacteriuria in pregnancy f/u
rescreen
89
cystitis path
bladder infection = gram negatives
90
cystitis pt
urgency, frequency, dysuria
91
cystitis dx
urinalysis
| urine culture
92
cystitis tx
```
uncomplicated: 3 d
complicated (Penis, Plastic, Procedure, or ambulance Pyelo): 7 d
Amoxicillin (1st line)
nitrofurantoin (if PCN allergy)
TMP-SMX (optional)
```
93
pyelonephritis path
infection of kidney
94
pyelo pt
urgency, frequency, dysuria
| nausea, vomiting, CVA tenderness
95
pyelo dx
urinalysis = wbc casts
| urine culture, blood culture
96
pyelo tx
IV abx = ceftriaxone or AMP-Sulbact abx x10d
97
perinephric abscess path
walled off kidney infection
98
perinephric abscess pt
pyelo that does not get better
99
perinephric abscess dx
CT or u/s
100
perinephric abscess tx
I&D
| 14d of abx
101
syphilis path
treponema pallidum
102
syphilis pt
```
primary = single, painless ulcer with lymphadenopathy
secondary = rash and fever, targetoid lesions on palms and soles
tertiary = any neuro symptoms
```
103
syphilis dx
```
primary = dark field microscopy
secondary = RPR, confirm with FTA-ab
tertiary = RPR -> LP w CSF RPR and FTA-ab
```
104
syphilis tx
```
primary = PCN IM x1
secondary = PCN IM one week x 3 wks
tertiary = PCN IV x 14d
```
105
syphils f/u
PCN allergic? -> doxycycline
pregnant and PCN allergic? -> PCN desensitization
Jarisch-Herxheimer Reaction = fever and symptoms worsen after treatment -> give ASA
106
haemophilus ducreyi path
gram negative
107
haemophilus ducreyi pt
single, panful ulcer with lymphadenopathy
108
haemophilus ducreyi dx
gram stain and culture
109
haemophilus ducreyi tx
azithromycin or ciprofloxacin
110
herpes simplex path
virus that hides in DRG
111
herpes simplex pt
painful burning prodrome
112
herpes simplex dx exam
multiple vesicles on erythematous bases
may coalesce to look like one ulcer
no lymphadenopathy
113
herpes simplex dx
clinical
| HSV PCR
114
herpes simplex tx
acyclovir
115
molluscum contagiosum path
self-limiting infection
116
molluscum contagiosum pt
central umbilication
| multiple 'vesicles'
117
molluscum contagiosum dx
clinical
118
molluscum contagiosum tx
freeze
119
lymphogranuloma venerum path
C. trachomatis
120
lymphogranuloma venerum pt
painless singular ulcer with painful supportive lymphadenopathy
121
lymphogranuloma venerum dx
clinical... NAAT if prompted
122
lymphogranuloma venerum tx
doxycycline
123
lice path
louse lives on hair-bearing regions
| sharing hats, combs
124
lice pt
itchy scalp
| nits in hair
125
lice dx
clinical
126
lice tx
permethrin shampoo
127
scabies path
contact dermatitis from burrowing and pooping bugs/eggs
| household contacts
128
scabies pt
itching and rash
family members all have it
burrows between fingers and toes
129
scabies dx
scrape lesions, see eggs and organisms
130
scabies tx
permethrin cream
131
fungal infections path
fungus
132
fungal infections pt
itchy feet, groin
133
fungal infections dx
discoloration of the skin
134
fungal infections dx
KOH prep = fungus
| culture
135
fungal infections tx
hair or nail involved? -> PO antifungals
hair or nail NOT involved? -> topical antifungals
terbinafine is best
136
osteomyelitis path
```
direct inoculation (probe bone)
indirect inoculation (hematogenous)
```
137
osteomyelitis pt
wound that probes to bone
bone pain
cellulitis anyway (xray for osteo)
recurrent ulcers that do not improve or fail to heal
138
osteomyelitis dx
1st: xray
best: MRI
best best: bx
139
osteomyelitis tx
surgical debridement
abx
-if not toxic, don't give any
-if toxic, go broad, deescalate
140
osteomyelitis f/u
ESR and CRP (track resolution, not dx)
141
cellulitis path
bacterial infection of subQ
142
cellulitis pt
```
portal = ulcer, puncture, laceration
rash = warm, hot, tender skin with clear demarcations
```
143
cellulitis dx
r/o osteo with xray
r/o osteo - can you probe to bone?
r/o osteo - but only if really concerned, with MRI
144
cellulitis tx
S. pneumo: 1st gen cephalosporin
| MRSA: vanc IV, clinda or TMP-SMX
145
gas gangrene path
dirty wound
gas producing organisms
clostridium perferingins
146
gas gangrene pt
cellulitis and crepitus
147
gas gangrene dx
1st: xray shows gas
148
gas gangrene tx
emergency -> immediate debridement
| abx = ß-lactams and clindamycin (inhibits toxin formation)
149
impetigo path
strep pyogenes
150
impetigo pt
honey-colored crusts, usually on top of another wound or sore
151
impetigo dx
clinical
152
impetigo tx
amoxicillin
| if fails, 1st gen cephalosporin = cephalexin
153
necrotizing fasciitis path
rapid spread of infection through fascial planes
| strep pneumo
154
necrotizing fasciitis pt
rapidly expanding cellulitis
pain out of proportion to exam
diabetes
blue-gray discoloration of skin
155
necrotizing fasciitis dx
xray normal
| surgical specimen required
156
necrotizing fasciitis tx
emergency surgery and debridement
broad abx
hyperbaric oxygen
157
major criteria for endocarditis
- sustained bacteremia by organism known to cause IE (strep, staph, HACEK)
- endocardial evidence by echo
- new valvular regurgitation (increase or change of pre-existing not adequate)
158
minor criteria for endocarditis
- predisposing risk factor (valve disease or IVDA)
- fever > 38 C
- vascular phenomena (septic emboli arterial, pulmonary, and janeway lesion)
- immunologic phenomena (glomerulonephritis, Osler nodes, Roth spots, RF)
159
definite endocarditis
- 2 major criteria (blood culture and echo)
- one major and three minor
- 5 minor
160
possible endocarditis
- 1 major and 1 minor (almost every bacteremic pt)
| - 3 minor
161
rejected endocarditis
- firm alternative dx explaining evidence for IE
- resolution of everything in 4d
- no pathologic evidence (biopsy?) at surgery or death
- failure to meet criteria as above
162
diagnostic steps of subacute endocarditis
blood cultures x3
- one hour apart
- NO abx
163
diagnostic steps of acute endocarditis
blood cultures x2 now
- start empiric abx
- f/u cultures
164
if unsure of endocarditis
trans thoracic echo
165
if are sure of endocarditis
trans esophageal echo
166
antibiotics of endocarditis - native valve
vancomycin
167
abx of endocarditis - prosthetic valve
< 60d = vancomycin, gentamicin, cefepime
60-365d = vancomycin, gentamicin
>365d = vancomycin, gentamicin, ceftriaxone
168
when to do surgery for endocarditis?
>15mm even without embolization
>10mm + embolization
abscess
valve destruction or CHF
