Infectious Disease Flashcards
1
Q
How do you diagnose Legionella?
A
Urine legionella antigen test
2
Q
How do you diagnose chlamydophila pneumonia?
A
PCR
3
Q
What type of pneumonia presents with serum cold agglutinins?
A
Mycoplasma
4
Q
How do you diagnose pneumococcal pneumonia?
A
Urine pneumococcal antigen testing
5
Q
What are the CURB-65 criteria for hospital admission for pneumonia?
A
-Confusion
-Uremia (BUN over 19)
-Respiratory rate over 30
BP lower than 90 / 60
-Age over 65
6
Q
What are the top three causes of pneumonia in neonates?
A
GBS
E. Coli
Listeria
(GEL)
7
Q
What is the most common cause of pneumonia in children? Young adults?
Elderly?
A
Children = viruses or strep
YA = Mycoplasma pneumonia
Elderly = S. pneumo
8
Q
What are the three major bacteria that cause atypical pneumonia?
A
Mycoplasma
Legionella
Chlamydophila
9
Q
What are the top three nosocomial causes of pneumonia?
A
GNRs
Staph anaerobes
Pseudomonas
10
Q
What is the most common infectious agent(s) implicated in aspiration pneumonia?
A
Anaerobes
11
Q
What is the treatment for outpatient pneumonia?
A
Macrolide or doxycycline
12
Q
What is the treatment for inpatient pneumonia with multiple relevant comorbidities?
A
Fluoroquinolones
or beta-lactam+macrolide
13
Q
What is the treatment for CAP requiring hospitalization?
A
Fluoroquinolone or antipseudomonal beta-lactam + macrolide
14
Q
What is the treatment for CAP requiring ICU care?
A
Antipneumococcal beta lactam + (azithromycin or fluoroquinolone)
15
Q
What is the treatment for hospital/institution acquired pneumonia?
A
Cephalosporin
Aminoglycoside or flouroquinolone
16
Q
What is the treatment for MRSA pneumonia?
A
Vanco
17
Q
What marks an active infection of TB?
A
Mycobacterial culture of sputum or blood
18
Q
What is the TB drugs that turns urine, sweat, and tears orange?
A
Rifampin
19
Q
What is the classic side effect of ethambutol?
A
optic neuritis
20
Q
What are the classic side effects of INH? (2)
A
Peripheral neuropathy
Hepatitis
21
Q
What qualifies as latent TB diagnosis?
A
+ PPD or GOLD, but negative sputum cultures
22
Q
What is the treatment for active TB?
A
RIPE x 2 months
INH+rifampin x 4 months
23
Q
What is the treatment for latent TB?
A
INH x 9 months
24
Q
True or false: early treatment for strep pharyngitis can prevent both rheumatic fever and glomerulonephritis
A
False–not glomerulonephritis
25
What is the hemolytic pattern of GAS?
ALpha
26
What are the common viral causes of pharyngitis?
Rhinovirus
| Coronavirus
27
What amount of induration indicates a positive PPD for: HIV, or close to TB
5 mm
28
What amount of induration indicates a positive PPD for: Indigent/homeless, residents of developing nations
10 mm
29
What amount of induration indicates a positive PPD for: healthcare workers
10 mm
30
What amount of induration indicates a positive PPD for: healthy with no known risk factors?
15 mm
31
What is the treatment for GAS pharyngitis?
Amoxicillin x 10 days
32
What are the two major nonsuppurative complications of strep pharyngitis?
Rheumatic fever
| glomerulonephritis
33
What are the two major suppurative complications of strep pharyngitis?
Cervical LAD
Mastoiditis
Simusitis
OM
34
What is the difference in timeframe for acute vs chronic sinusitis?
- Acute = less than 1 month
| - Chronic = more than 3 months
35
What two infectious agents are diabetic and immunosuppressed patient particularly susceptible to in terms of sinusitis?
Mucor
| Rhizopus
36
Where is coccidioidomycosis found geographically?
Southwest US
37
What is the treatment for acute coccidioidomycosis?
- azole for mild
| - IV amp B for disseminated
38
What is antigenic drift?
Small, gradual changes in surface proteins through point mutations, which are the cause of seasonal variance
39
What is antigenic shift?
Acute, major change in the influenza A subtype leading to pandemics
40
What are the histologic findings of coccidioidomycosis?
Spherules
41
At what age can kids get their first flu vaccine?
6 months for injectable
| 2 years for LAV
42
What are the top three most common causes of meningitis in newborns?
1. GBS
2. E.coli
3. Listeria
43
What are the top three most common causes of meningitis in children (6 months - 6 years)?
1. Strep pneumo
2. N, meningitidis
3. H. flu
44
What are the top three most common causes of meningitis in 6-60 year olds?
1. N meningitidis
2. Strep pneumo
3. Enterovirus
45
What are the top three most common causes of meningitis in 60+?
1. Strep pneumo
2. GNRs
3. Listeria
46
What are the classic CSF findings of multiple sclerosis?
Increased gamma globulins
| monoclonal bands
47
What is the prophylaxis for people in close contact to a pt who has contracted meningococcal meningitis?
Rifampin or cipro
48
What are the 2 abx of choice to treat neonatal meningitis?
Ampicillin + gentamicin (cefotaxime)
49
What are the 2 abx for treating 1-3 mo with meningitis?
Vanco + Ceftriaxone (cefotaxime)
50
What are the 2 abx for treating meningitis in 3 mo to adulthood?
Vanco + ceftriaxone (cefotaxime)
51
What are the three abx for treating meningitis in a 60 yo +?
Ampicillin + vanco + ceftriaxone (cefotaxime)
52
RBCs in a LP without a h/o trauma strongly suggests what cause of meningitis?
HSV
53
With what cause of meningitis is dexamethasone given?
Strep pneumo
54
What are the two most common causes of encephalitis?
HSV and arboviruses
55
What are the usual s/sx of encephalitis? (4)
- AMS
- HA
- Fever
- Seizures
56
What are the five causes of encephalitis that are diagnosed with PCR of CSF?
```
VZV
HSV
EBV
CMV
Enteroviruses
```
57
What infectious process can cause focal neurologic symptoms?
Brain abscess
58
What is the treatment for HSV and CMV encephalitis respectively?
```
HSV = acyclovir
CMV = ganciclovir
```
59
What is the treatment for RMSF encephalitis? Lyme disease?
```
RMSF = doxycycline
Lyme = ceftriaxone
```
60
What is the appearance of brain abscesses on imaging?
Ring enhancing lesions (d/t fibrotic capsule)
61
What are the common infectious etiologies of brain abscesses?
Strep
Staph
Anaerobes
62
What is the bacteria that is usually implicated in brain abscesses that spread from the paranasal sinuses?
Strep milleri
63
If a brain abscess is the result of hematologic spread of bacteria, where in the brain are they usually found?
Middle cerebral artery distribution (usually multiple) at the Gray-white junction
64
What are the s/sx of brain abscesses?
- Increased ICP
- Focal neurologic deficits
- HA
65
Which CNs are often affected by brain abscesses?
CN III and VI
66
Why is CSF analysis contraindicated in most cases of brain abscesses?
High ICP 2/2 abscess can cause herniation
67
What are the lab values that are often elevated with brain abscesses?
ESR and CRP
68
What is the treatment for brain abscesses?
IV abx and surgical drainage
| -Dexamethasone or mannitol if increased ICP
69
What is the difference in the clinical value of CD4 counts and viral load for HIV pts?
CD4 = degree of immunosuppression
| Viral load = rate of disease progression
70
What is the screening test for HIV? Confirmatory?
```
Screening = ELISA
Confirmatory = western blot
```
71
What is the role of HIV RNA PCR?
Used for cases of acute HIV infection, since this time period may result with a negative western blot
72
What is the general schema of HIV treatment?
2 NRTIs + (1 NNRTI or protease inhibitor or integrase inhibitor)
73
What are the common side effects of protease inhibitors? (3) What is the common suffix?
-"navirs"
Hyperglycemia
Hyperlipidemia
Lipodystrophy
74
What are the common side effects of NRITs? (2) What is the common suffix?
- Bone marrow suppression
| - neuropathy
75
What are the common side effects of indinavir?
- crystal induced nephropathy
| - nephrolithiasis
76
What are the common side effects of didanosine?
Pancreatitis
77
What are the common side effects of abacavir?
hypersensitivity rxn
78
What are the common side effects of nevirapine
Liver failure
79
What are the common side effects of efavirenz?
Vivid dreams
| Hallucinations
80
What is the PEP for HIV?
source, begin ART as soon as possible with a basic two drug regimen or an expanded regimen of three or more drugs for 4 weeks, depending on the severity of the source infection.
81
What are the only two live vaccines that can be given to HIV pts?
MMR and varicella
82
What is the drug and CD4 count at which prophylaxis if given for: PCP?
200
| TMP-SMX
83
What is the drug and CD4 count at which prophylaxis if given for: MAC
50
| Azithromycin
84
What is the drug and CD4 count at which prophylaxis if given for: toxo?
100
| Double strength TMP-SMX
85
What is the drug and mm induration at which prophylaxis if given for: TB
5 mm or if high risk
| INH x 9 months OR rifampin x 4 months
86
What is the treatment for candida esophagitis and thrush in HIV pts?
```
Esophagitis = fluconazole
Oral = above OR nystatin swish and swallow
```
87
What is the drug and s/sx at which prophylaxis is given for HIV pts with: HSV
Multiple recurrences
| Daily acyclovir
88
What are the 8 major pathogens that signify significant T cell collapse in HIV pts?
- Toxo
- MAC
- PCP
- Candida
- Cryptococcus
- TB
- CMV
- Cryptosporidium
89
What is the classic exposure that causes cryptococcal meningitis?
Exposure to pigeon droppings
90
How is cryptococcal meningitis different from other etiologies of meningitis in terms of presentation?
Usually no meningeal signs
91
What is the diagnostic test for cryptococcal meningitis?
Antigen testing of CSF
92
What is the treatment for cryptococcal meningitis?
Amp B + fluconazole x 2 weeks, then fluconazole
93
What is the classic exposure for histoplasmosis? Where?
Bird or bart excrement in ohio and mississippi river valleys
94
What are the severe s/sx of histoplasmosis?
fever
weight loss
HSM
95
What are the CXR findings of histoplasmosis?
diffuse nodular densities
96
What is the diagnostic test of choice for histoplasmosis?
Urine and serum polysaccharide antigen test
97
What is the treatment for histoplasmosis causing the following:
- Mild pulmonary disease
- Chronic cavitary lesions
- Severe acute pulmonary disease or disseminated disease
- Mild pulmonary disease = supportive
- Chronic cavitary lesions = itraconazole x 1 year
- Severe acute pulmonary disease or disseminated disease = amp B
98
What is the stain that classically used to diagnose PCP pneumonia?
Silver stain
99
When should PCP pneumonia be treated with steroids?
If PaO2 less than 70, or A-a gradient over 35
100
What are the visual symptoms associated with CMV retinitis?
Retinal detachment --floaters and visual field changes
101
AIDS cholangiopathy is associated with which infectious agent?
CMV
102
What are the symptoms of CMV pneumonitis, and in whom is it classically seen?
- Non-productive cough
| - More common in pts with malignancy
103
What are the three major neurologic manifestations of CMV?
Polyradiculopathy
Transverse myelitis
Encephalitis
104
What is the treatment for CMV infections?
ganciclovir or valganciclovir
105
What is the classic presentations of disseminated MAC attack?
Weakness, fever,weight loss
| AIDS pts not on HAART
106
What are the lab findings of MAC?
increased serum alk phos
| Increased LDH
107
What is the treatment for MAC? 2nd line?
1. Clarithromycin
| 2. ethambutol + rifabutin
108
Toxo has a predilection for what part of the brain?
basal ganglia
109
What is the treatment for toxo?
Pyrimethamine + sulfadiazine and leucovorin
110
What are the two ddx that should be considered with ring enhancing lesions on MRI in the brain of an AIDS pt?
toxo vs CNS lymphoma
111
What is the causative agent of lymphogranuloma venereum? S/sx?
- Chlamydia
- Painless transient papule/pustule, followed by painful swelling of inguinal lymph nodes AND/OR anal discharge, rectal strictures
112
What is the diagnostic test for chlamydia?
URine test (nucleic acid test)
113
What will gram stain show with chlamydia?
PMNs, but no bacteria
114
What is the treatment for chlamydia?
Doxycycline PO x7 days or azithromycin IM x1
115
What are the gram stain and morphologic findings of gonorrhea?
Gram negative intracellular diplococcus
116
What is the classic d/c found with gonorrhea?
Greenish-yellow
117
What is the diagnostic test of choice for gonorrhea?
MAAT but culture is gold standard
118
What is the treatment for gonorrhea?
Ceftriaxone IM AND PO (regardless of whether chlamydia is present)
119
True or false: Condoms prevent the spread of gonorrhea
True
120
What defines the early latent stage of syphilis? late latent?
```
early = from resolution of primary or secondary, to end of first year
Late = after 1 year
```
121
What stage of syphilis are gummas seen?
tertiary
122
```
What are the:
-Viruses
-autoimmune diseases
-drugs
That can cause a false positive VDRL test?
```
- HIV/HSV/Hepatitis
- IV drugs (and others)
- Rheumatic fever/rheumatoid arthritis
- SLE
123
What is the treatment for primary, secondary, and tertiary syphilis?
- Primary and secondary = benzathine PCN, IM
- tertiary (latent) = above
- Tertiary (neuro) = IV PCN
124
What are the components of the SEEKS PP mnemonic for that infectious etiologies of UTIs?
```
Serratia
E.coli
Enterobacter
Klebsiella
Staph saprophyticus
Pseudomonas
Proteus mirabilis
```
125
What is the only group of patients that warrant treatment for asymptomatic UTIs?
Children and pregnant women
126
What is the abx of choice for treating UTIs in pregnant women?
Nitrofurantoin (macrobid)
127
What is the risk of untreated UTI in prego women?
Pyelo
128
What is the first line abx for pyelo?
Fluoroquinolones
129
What is the classic lesion of granuloma inguinale? Pain? What causes it? Treatment?
- Beefy-red ulcer
- painless
- Klebsiella granulosum
- doxy or azithromax
130
What are the four components of SIRS criteria?
- Temp not [36,38]
- Tachypnea (over 20 or PaCO2 less than 32
- Tachycardia over 90 bpm
- Leukocytosis over 12 or under 4
131
What is the mosquito that transmits malaria?
Anopheles
132
Which strain of malaria carries the worst prognosis?
Falciparum
133
What is the diagnostic test for malaria?
Giemsa or wright stained thick and thin blood filament
134
What is the treatment for malaria?
- Chloroquine
- If vivax or ovale, use primaquine to kill liver infx
- Atovaquone if chloroquine resistant area
135
How long after initial infection can malaria cause s/sx?
immediately - Years
136
What should be checked first in a pt with malaria who develops AMS?
Fingerstick BG
137
What test can confirm a diagnosis of Mono if a heterophile spot is negative?
EBV antibodies
138
What will a CBC often show with mono? (2)
Thrombocytopenia with lymphocytic lymphocytosis
139
True or false: the rash that develops from EBV given PCN i pruritic
True
140
What lethal GI complication can develop from EBV infx?
Fulminant hepatic necrosis
141
True or false: fever of unknown origin always needs abx
False--not unless other s/sx of infx present
142
What are the three 3's of FUO diagnostic criteria?
Fever for 3 weeks that remains undiagnosed following 3 outpt visits, OR 3 days of hospitalization
143
What is the definition of neutropenic fever?
Fever over 101 F (38.3 C) in a pt with neutropenia (less than 500 PMNs)
144
Why should a rectal exam be deferred in a neutropenic patient?
Risk of thrombocytopenia and thus bleeding if anus is manipulated
145
When should antifungals be started empirically in pts with neutropenic fever?
If febrile after 72 hours of abx therapy
146
What antibiotics are indicated for treating neutropenic fever empirically?
Anti-pseudomonal (zosyn, aka piperacillin-tazobactam)
147
What are the common s/sx of Ehrlichiosis?
HA, fever, chills, AMS and myalgias
148
What are the lab abnormalities common to Ehrlichiosis? (3)
Leukopenia
Thrombocytopenia
elevated LFTs
149
What is the treatment for Ehrlichiosis?
Doxycycline
150
What is the tick that carries lyme disease?
Ixodes tick
151
What are the s/sx of primary, secondary, and tertiary Lyme disease?
1. Rash
2. Migratory polyarthropathies, bells palsy, 3' heart block
3. Arthritis and encephalopathy
152
When does IgM and IgG tests for lyme disease become positive?
```
IgM = 1-2 weeks
IgG = 2-6 weeks
```
153
What is the confirmatory test for lyme disease?
ELISA and (then) Western blot (Western blot alone has high false = rate)
154
What is the treatment for early and late lyme disease?
```
Early = doxycycline
Late = Ceftriaxone
```
155
When is prophylaxis for lyme disease indicated? (3)
- tick attached for over 36 hours
- Within 72 hours of removal
- Local rate of infx over 20%
156
What are the characteristics of the rash of RMSF? How does the rash of RMSF spread?
- Macular turns to petechial/purpuric
| - Starts on the wrists, spreads centrally
157
What is the treatment for RMSF in pregnant women?
Chloramphenicol
158
What are the two major complications of RMSF?
- AMS
| - DIC
159
True or false: Neisseria conjunctivitis is an ocular emergency, and requires inpatient treatment
True
160
What is the treatment for Neisseria conjunctivitis?
IV ceftriaxone
161
What is the treatment for chlamydial conjunctivitis?
Azithromycin or tetracycline
162
What is the abx of choice for otitis externa?
Topical ciprofloxacin
163
What is the most common etiologic agent for endocarditis in the setting of
- IV drug abuse
- Dental procedures with native valves
- Prosthetic valves
- GI malignancy
- fungal infx
- IV drug abuse = staph aureus
- Dental procedures with native valves = strep viridans
- Prosthetic valves = staph epidermidis
- GI malignancy = strep bovis
- fungal infx = candida and aspergillus
164
What are the HACEK organisms?
```
Haemophilus
Actinobacillus
Cardiobacterium
Eikenella
Kingella
```
165
What is the empiric abx (2) for infective endocarditis?
Vanco and gentamicin
166
What are the major (2) and minor (4) duke criteria for infective endocarditis?
major = Blood cultures + evidence of endocardial involvement
Minor =
- risk factors +
- Fever
- Vascular phenomena
- Immunologic phenomena
167
When is preprocedure prophylaxis indicated for infective endocarditis?
- Significant heart defects (prosthetic valves, unrepaired defect)
- Undergoing high risk procedure
168
What is the preferred abx for preprocedure prophylaxis for infective endocarditis?
Amoxicillin
169
True or false: there is no person-person spread of anthrax
True
170
What are the cutaneous characteristics of anthrax?
- Pruritic papule the enlarges to forms an ulcer surrounded by a satellite/ bulbous lesions.
- +regional LAD
- Forms into black eschar
171
What are the pulmonary manifestations of anthrax?
Hemorrhagic mediastinitis (no pulmonary infiltrates)
172
What is the treatment for anthrax? Prophylaxis?
Ciprofloxacin for both
173
What two labs are elevated with osteomyelitis?
CRP and ESR
174
What are the XR findings of osteomyelitis?
Periosteal elevation
175
How do you diagnose and treat osteomyelitis?
- Bone aspiration (although increases risk for infection)
| - Surgical debridement followed by IV Abx
176
If a pt has a PCN allergy, but needs a beta lactam abx, which abx class has minimal cross reactivity?
Cephalosporins
177
What are the common infectious agents implicated in osteomyelitis in the following contexts:
- IV drug abuse
- Sickle cell
- Hip replacement
- Foot puncture wound
- DM
- IV drug abuse = staph aureus
- Sickle cell = salmonella
- Hip replacement = staph epidermidis
- Foot puncture wound = pseudomonas
- DM = pseudomonas, staph, strep
