ID key points Flashcards
1
Q
3 MCCs of viral meningitis?
A
- Enterovirus
- HSV 2
- Arboviruses
2
Q
Viral meningitis + parotitis or orchitis is a clue to what bug?
A
Mumps
3
Q
Viral meningitis + rash is a clue to which two bugs?
A
Enterovirus, HIV
4
Q
Viral meningitis + pharyngitis is a clue to which bug?
A
HIV
5
Q
Viral meningitis + genital lesions is a clue to which bug?
A
HSV2
6
Q
General management of viral meningitis? When can you stop empiric anti-microbials?
A
Supportive, can stop once CSF Cx r/o bacterial meningitis
7
Q
5 MCCs of bacterial meningitis?
A
- Strep pneumo
- N. meningitidis
- GBS
- H flu
- Listeria monocytogenes
8
Q
When should you start empiric antimicrobial therapy in suspected bacterial meningitis?
A
Immediately
9
Q
What non-antimicrobial drug should be started as adjunctive therapy in all cases of bacterial meningitis in developed countries?
A
Dexamethasone
10
Q
When should you start empiric antimicrobial therapy in suspected brain abscess?
A
Immediately
11
Q
Successful Tx of a brain abscess typically consists of what 2 therapeutic modalities?
A
- Anti-microbial therapy
2. Surgical drainage
12
Q
Name 2 places that spinal epidural abscesses commonly arise from
A
Infected vertebral discs
Inected intervertebral body disc spaces
13
Q
RFs for spinal epidural abscesses? (9)
A
- Prolonged epidural catheter placement
- Steroid or analgesic injections
- DM
- HIV
- Trauma
- IVDU
- Tattooing
- Alcoholism
- Accupuncture
14
Q
How many sets of BCx should you get for a spinal epidural abscess?
A
2
15
Q
Cranial subdural empyemas typically arise as a complication of which processes? (3)
A
Sinusitis
OM
Mastoiditis
16
Q
Cranial subdural empyemas are a medical emergency. In addition to immediately evaluating the patient, which consult should you call?
A
Neurosurgery
17
Q
Characteristic imaging findings of HSV encephalitis?
A
Unilateral or bilateral localized infection of the temporal lobes
18
Q
CSF findings in HSV encephalitis?
A
Lymphocytic pleocytosis +/- rbcs (if necrosis is extensive)
19
Q
What test is highly sensitive and specific for diagnosis of HSV encephalitis?
A
HSV PCR of the CSF
20
Q
All patients suspected of having encephalitis should get what anti-viral drug empirically?
A
IV ACV
21
Q
VZV encephalitis is MC in which 2 patient populations?
A
HIV/AIDS
Defects in cellular immunity
22
Q
Dx of VZV CNS infection?
A
VZV PCR of the CSF
23
Q
Tx of VZV encephalitis?
A
Parenteral ACV
24
Q
Tx of VZV vasculopathy?
A
Parenteral ACV
25
What percent of patients with West Nile virus develop neuroinvasive disease?
Less than 1%
26
3 general presentations of West Nile neuroinvasive disease?
Meningitis, encephalitis, or myelitis. Note it can present with just one or with an overlap syndrome.
27
Dx of West Nile neuroinvasive disease?
CSF serology
28
When do most patients with West Nile neuroinvasive disease develop detectable IgM antibody to West Nile?
Within 1st week of Sx
29
Name 4 presenting features of anti-NDMA receptor encephalitis
1. Choreoathetosis
2. Psych Sx
3. Seizures
4. ANS instability
30
Anti-NDMA receptor encephalitis is associated with what underlying condition in over 50% of patients?
Ovarian teratoma
31
Dx of anti-NDMA receptor encephalitis?
Detection of anti-NDMAR antibody in serum
32
Tx of anti-NDMA receptor encephalitis?
Remove teratoma + immunosuppression with either steroids or IVIG
33
MC form of prion disease in humans?
CJD
34
Which form of CJD is most common?
Sporadic
35
2 major causes of iatrogenic CJD transmission?
1. Use of growth hormone prepared from cadaveric pituitaries
| 2. Contaminated cavaderic dura mater allografts
36
2 major causes of variant CJD transmission?
1. Eating contaminated beef
| 2. Blood/blood products from vCJD-infected donors
37
MCC of cellulitis w/ purulent drainage or exudates?
MRSA
38
MCC of non-purulent cellulitis?
Beta-hemolytic strep
39
Skin infections are typically diagnosed clinically. What are 3 circumstances when radiography would be considered?
1. Dx is uncertain
2. Nec fasc is suspected
3. Concern for associated abscess or foreign body
40
Primary Tx of CA-MRSA cutaneous abscess?
I&D
41
When are antibiotics indicated for CA-MRSA cutaneous abscess? (8)
1. If I&D is ineffective
2. Extensive disease
3. Rapidly progressive disease w/ associated cellulitis
4. Presence of immunodeficiencies or other CMx
5. Very young or very old patient
6. Clinical signs of systemic illness
7. Involved area is difficult to drain
8. Presence of septic phlebitis
42
Clues to an underlying necrotizing SSTI? (3)
1. Systemic toxicity w/ fever, chills, AMS, hypoTN
2. Pain out of proportion to exam
3. Loss of sensation
43
Why can loss of sensation occur in nec fasc?
Destruction of cutaneous nerves
44
Gold standard for Dx and Tx of nec fasc?
Early surgical exploration
45
3 components of early management of toxic shock syndrome?
1. Adequate resuscitation to maintain tissue perfusion
2. Identification of the cause and focus of infection
3. Source control
46
When managing toxic shock syndrome, what does source control typically involve?
Surgical debridement
47
3 ways to decrease the risk of infection in animal bites?
1. Prompt wound irrigation w/ NS
2. Removal of any foreign bodies
3. Debridement of necrotic tissue
48
All patients with animal bites should be assessed for need for prophylaxis against which 2 infections?
Tetanus and rabies
49
Which animal bite patients require prophylactic amox-clavulanate? (5)
1. Immunosuppressed
2. Moderate-to-severe wounds, esp on face or hands
3. Wounds near a joint or bone
4. Wounds associated with significant crush injury
5. Wounds associated with significant edema
50
Which human bite wounds require Abx Ppx, and which Abx is used?
All require ppx w/ amox-clavulanate
51
3 components of wound care for diabetic foot infections?
1. Wound cleansing
2. Debridement
3. Off-loading of foot pressure
52
Which patients with new diabetic foot wounds get imaging?
All of them!
53
Which age group is more likely to get CAP?
Older adults
54
MCC of CAP?
Strep pneumo
55
2 MC respiratory viruses contributing to development of CAP?
Influenza A and B
56
MRSA as a cause of CAP is MC w/ nosocomial exposures. What are some other risk factors? (3)
1. Hemodialysis
2. SNF exposure
3. Exposure to people with SSTI
57
5 clinical symptoms of CAP?
1. Fever
2. Cough
3. Dyspnea
4. Sputum production
5. Pleuritic chest pain
58
What radiographic finding is required for a Dx of PNA?
Pulmonary infiltrate on CXR
59
Indications for microbiologic testing w/ sputum Cx and BCx in CAP? (8)
Hospitalized patients with one or more of the following:
1. ICU admission
2. Cpx like pleural effusion or cavitary lesion
3. Underlying lung disease
4. Active EtOH abuse
5. Asplenia
6. Liver disease
7. Leukopenia
8. Unsuccessful outpatient anti-microbial therapy
60
Empiric outpatient therapy for CAP in patients w/o CMx or recent antimicrobial use? (2 options)
1. Macrolide
| 2. Doxy
61
Empiric outpatient therapy for CAP in patients w/ CMx, recent antimicrobial use, or living in an area with highly prevalent macrolide-resistant strep pneumo? (2 options)
1. Respiratory FQ
| 2. Combo therapy w/ beta-lactam + macrolide (alternate to macrolide is doxy)
62
When can hospitalized CAP patients be switched from parenteral Abx to PO?
When clinically stable
63
Does it improve outcomes to continue inpatient monitoring of CAP patients who have been switched from parenteral to PO Abx?
Nope
64
Pts w/ PNA who are treated with the appropriate Abx typically show clinical improvement when?
Within 2-3 days
65
What are RFs for unsuccessful Tx of CAP?
1. Multilobar PNA
2. MRSA
3. Legionella
4. Gram-neg bacilli
5. PNA severity index of 90 or more
6. Initial Tx w/ an anti-microbial regimen to which the causative pathogen was not susceptible
66
Tx courses for CAP longer than _________ have not shown to have a clinical benefit
5 days
67
Why shouldn't you routinely use follow-up CXR s/p CAP?
CXR findings may linger beyond clinical improvement and symptom resolution
68
When do Lyme disease Sx typically first appear?
1-4 weeks s/p infection
69
Characteristic initial Sx of Lyme?
Erythema migrans (single target lesion)
70
What percent of Lyme patients will develop erythema migrans?
60-80%
71
Dx of early Lyme disease if erythema migrans is present?
Documentation of erythema migrans + compatible epidemiologic history
72
Why isn't serologic testing indicated in early Lyme?
Antibodies may not be present yet, leadign to false negative testing in early localized disease
73
Are antibodies typically present during disseminated Lyme?
Yup
74
Dx of disseminated Lyme?
2 step serologic testing: ELISA followed by confirmatory Western blot
75
Mx of post-lyme disease syndrome?
Treat the symptoms. No Abx bc they're no longer infected!
76
STARI is clinically indistinguishable from what other infectious disease?
Localized Lyme
77
Tx of STARI?
Oral antibiotic active against localized Lyme disease (bc impossible to tell if it's Lyme vs STARI). Thus doxy is best, amoxicillin if can't take doxy (young kids, pregnant women)
78
Describe typical presentation of babesiosis
Either ASx or mild febrile illness w/ myalgias, HA, fatigue
79
What are 4 potential features of severe babesiosis?
1. Acute respiratory failure
2. AKI
3. DIC
4. Splenic rupture
80
What's the most sensitive test for diagnosis of mild babesiosis?
PCR bc these patients typically have low parasite counts
81
Sensitivity of microscopy of Giemsa or Wright-stained blood smears in the diagnosis of babesiosis depends on what?
Level of parasitemia
82
Tx of choice for mild-moderate babesiosis?
Atovaquone + azithro
83
Tx of choice for severe babesiosis?
Clinda + quinine
84
Human monocytic ehrlichiosis and human granulocytic anaplasmosis typically present as non-specific febrile illnesses accompanied by what 4 Sx?
1. HA
2. Myalgia
3. Arthralgia
4. Meningismus
85
What test is extremely sensitive for ehrlichiosis and anaplasmosis if done before initiation of Abx?
Whole blood PCR
86
What drug should be given empirically when considering ehrlichiosis or anaplasmosis? Why?
Doxy- delay in therapy is a/w adverse clinical outcomes
87
What diagnosis should be considered in any patient presenting w/ fever and possible tick exposure?
RSMF
88
Describe utility of serologic testing during acute illness w/ RSMF
Limited utility
89
DOC for all spotter fever group rickettsioses? Alternate in pregnancy?
Doxy. Alt is chloramphenicol
90
RF for MDR UTI? (6)
1. Current or recent hospitalization
2. Immunocompromise
3. Presence of underlying structural abnormalities of the urinary tract
4. Previous UTI
5. Kidney Tpx
6. Recent anti-microbial therapy
91
3 major reasons for the increasing frequency of anti-microbial resistance among urinary pathogens in the community and hospitals?
1. Abx overuse
2. Inappropriate Tx of ASx bactiuria
3. Local differences in Abx use
92
5 indications for a culture of midstream, clean-void urine in the Dx of UTI?
1. Suspected pyelo
2. Complicated UTI
3. Recurrent UTI
4. Multiple anti-microbial allergies
5. Suspect resistant bug
93
Describe utility of UA/UCx as part of routine health surveillance in ASx patients
Not indicated
94
In women with acute uncomplicated cystitis, why are TMP-SMX or nitrofurantoin better options than fosfomycin?
Fosfomycin has lower efficacy and is more expensive
95
Acute uncomplicated pyelo: DOC and duration of treatment?
FQ for 5-7 days
96
Duration of Tx for acute complicated pyelo?
14 days
97
When can hospitalized patients w/ pyelonephritis be switched from IV to PO Abx?
Once can take PO and have clinical improvement
98
2 best options for PO Tx of acute pyelo?
TMP-SMX or FQ
99
What 2 drugs are options for Ppx in women with recurrent cystitis?
TMP-SMX or nitrofurantoin
100
While once-daily dosing of TMP-SMX or nitrofurantoin reduces episodes of cystitis in women w/ recurrent cystitis, what is the downside of using Abx Ppx?
ADEs are common
101
What is an option for Ppx of UTI in women with recurrent UTIs linked to sexual activity?
Abx Ppx with single dose given after sex. Options include nitrofurantoin or TMP-SMX
102
DOC for acute uncomplicated prostatitis? Duration?
PO FQ (levo or cipro) for 4-6 wk
103
After completing Tx for acute uncomplicated prostatitis, how can you check for response?
Repeat Cx
104
What percent of cases of TB in the US are in foreign-born people?
65%
105
What percent of HIV-associated deaths occur 2/2 TB (worldwide)?
20%
106
Immunocompromise is obviously a RF for development of TB. Name specific groups to be worried about? (8)
1. Immunosuppression 2/2 meds
2. HIV
3. Malignancy
4. DM
5. CKD
6. IVDU
7. Smokers
8. Malnutrition
107
What percent of active TB is pulmonary?
70%
108
9 s/s of pulmonary TB?
1. Fever
2. Chronic cough
3. Purulent or blood-streaked sputum
4. Chest pain
5. Malaise
6. Wt loss
7. Night sweats
8. Anorexia
9. Fatigue
109
What is latent TB?
ASx patient w/o clinical evidence of active TB is diagnosed w/ positive PPD or interferon gamma release assay
110
4 causes of false negative TB PPD
1. Very old
2. Very young
3. Immunosuppressed
4. Overwhelming active TB
111
2 reasons for false positive TB PPD?
1. Infection w/ atypical mycobacteria
| 2. Hx of bCG vaccine or chemo
112
What test is preferred for diagnosis of TB in patients who for the bCG vaccine or in those who are unlikely to return to have their skin test read?
interferon gamma release assay
113
For otherwise healthy adults, what is an alternative to the standard 9 months of INH for latent TB?
12 wk of once weekly INH/RIF
114
First line treatment plan for active TB?
8 wk of RIPE followed by 4-7 months of RI
115
How often should patients RTC for clinical evaluations during TB treatment?
At least monthly
116
Which patients getting TB treatment should get routine labs?
Those w/ baseline abnormalities or with increased risk of ADE
117
What vaccine is used in endemic countries to prevent disseminated TB and TB meningitis in kids?
bCG vaccine
118
What further identification do you need to do after documenting a mycobacterial infection?
Species-level identification
119
Specific DNA probes exist for which two non-TB mycobacteria? What species-level identification technique can identify the remaining mycobacteria?
Mycobacterium kansasii and MAC
| HPLC can ID the other species
120
MC manifestation of non-TB mycobacterial infection?
Pulmonary disease
121
MC non-TB mycobacterial species causing infection?
MAC
122
Which AIDS patients are at risk of disseminated MAC?
Those with CD4 under 50 who aren't getting MAC Ppx
123
How does mycobacterium kansasii typically present?
With a lung infection mimicking TB w/ cough, fever, weight loss, and cavitary lung disease
124
Name 3 rapidly growing mycobacteria that are becoming increasingly relevant as a cause of disseminated disease in immunosuppressed patients
M. abscessus
M. fortuitum
M. chelonae
125
Name 4 scenarios associated with SSTI 2/2 mycobacterium abscessus, fortuitum, and chelonae
1. Trauma
2. Surgery (esp w/ implanted prosthetics)
3. Catheter insertion
4. Cosmetic procedures (tattoos, piercing, pedi)
126
Name 4 common focal infections in systemic candidiasis
1. UTI
2. CNS infection
3. Bone and joint infection
4. Peritonitis
127
Typical DOC for most patients w/ candidemia?
An echinocandin
128
Candidemia patients with which 3 types of infection shouldn't get an echinocandin bc of poor tissue penetration?
1. UTI
2. Endophthalmitis
3. Meningitis
129
2 aspects of therapy in non-neutropenic patients w/ candidemia?
Antifungal therapy + intravascular catheter removal
130
2 indications for Tx of ASx candiduria?
1. Neutropenia
| 2. About to undergo a urologic procedure
131
4 potential manifestations of aspergillus pulmonary disease?
1. Colonization
2. ABPA
3. Aspergilloma (fungus ball)
4. Invasive aspergillosis
132
Definitive diagnosis of invasive aspergillosis? What's a helpful serologic diagnostic method?
Definitive: tissue Bx
Sero: Galactmannan antigen immunoassay
133
MC presentation of mucormycosis?
Rapidly fatal rhinocerebral infection
134
5 main s/s of rhinocerebral mucormycosis?
HA, epistaxis, proptosis, periorbital edema, decreased vision
135
MC site of disseminated cryptococcus?
CNS
136
Latex agglutination assay is highly sens/spec for Dx of cryptococcal meningitis in what group of patients?
Symptomatic pts w/ AIDS
137
How long do you continue maintenance therapy for pts w/ AIDS + cryptococcal meningitis?
Until both of the following:
1. they've responded to anti-retroviral therapy (with CD4 above 100 for at least 3 months
2. They've been getting anti-fungal therapy for at least 1 yr
138
1st and 2nd MC sites hit by blastomycosis? Name 3 other sites it commonly affects
1: Lungs
2: Skin
Other: bones, joints, prostate
139
Although histo is typically Asx, it has numerous symptomatic manifestations. Name 6
1. Pulmonary disease (acute or chronic)
2. Disseminated disease (acute or chronic)
3. Pulmonary nodules (histoplasmomas)
4. Granulomatous mediastinitis
5. Fibrosing mediastinitis
6. Broncholithiasis
140
How does primary coccidioidomycosis typically present? How long after initial exposure?
CAP, 1-3 wk s/p exposure
141
Preferred method of Dx for primary coccidioidal infection? How else can it be used
Serologic testing
| It can also be sued to monitor course of therapy. Repeat testing can help improve sensitivity if needed.
142
DOC for cutaneous sporotrichosis? Osteoarticular?
Itraconazole for both
143
Describe USPSTF recommendations for chlamydia screening
Sexually active women 24 and under: at least yearly
Older women: screen if have RFs
MSM: at least annually
144
Best test for Dx of chlamydia?
NAAT
145
NAAT for Dx of chlamydia: name 2 preferred specimen sites for men and 2 for women
Men: first void urine or urethral swab
Women: vaginal or endocervical sample
146
Describe USPSTF recommendations for gonorrhea screening
Sexually active women with one or more of the following:
1. Hx of gonorrhea
2. Another STI
3. New or multiple partners
4. Inconsistent condom use
5. History of exchanging sex for money or drugs
147
The USPSTF doesn't recommend screening men for gonorrhea, but what does the CDC suggest?
Annual screening for MSM
148
Best test for Dx of gonorrhea?
NAAT
149
Upon diagnosis of epididymitis, what further testing should you do? (4)
NAAT for GC/CT, UA/UCx
150
Upon diagnosis of PID, what further testing should you do? (5)
1. CT NAAT
2. GC NAAT
3. HIV screen
4. Syphilis serology
5. Pregnancy test
151
3 types of tenderness a/w PID?
1. Cervical motion tenderness
2. Adnexal tenderness
3. Uterine tenderness
152
Name 4 findings that increase the specificity of the Dx of PID
1. Fever
2. Mucopurulent cervical discharge
3. Elevated inflammatory markers
4. Leukocytes on a wet mount of vaginal fluid
153
Presentation of epididymitis?
Pain and swelling of the ipsilateral testis and spermatic cord
154
Recommended dosage of ceftriaxone for gonorrhea?
250 mg
155
When is PO cefixime appropriate for treatment of gonorrhea?
If parenteral ceftriaxone isn't available
156
What are 2 possible drugs that can be added to ceftriaxone in order to increase chance of eradication of GC?
Azithro or doxy
157
Describe the lesions of genital HSV
Painful vesicles that progress to ulcers on an erythematous base
158
Name 5 s/s of a primary genital HSV outbreak
1. Multiple genital lesions
2. Regional LAD
3. Fever
4. Myalgia
5. Malaise
159
Most sensitive modality for Dx for HSV?
PCR
160
Describe the lesion of primary syphilis
Painless ulcer at the site of inoculation w/ a firm raised border and clean base
161
Describe the rash of secondary syphilis
Generalized maculopapular rash involving the trunk and extremities, including palms and soles
162
Which stage of syphilis involves the CV system and has gummas?
Tertiary
163
DOC for all stages of syphilis?
PCN
164
Mx of sexual partners of pts diagnosed w/ syphilis?
Partners should be referred for eval. If exposed w/in the 90 days preceding diagnoses, they should get treated regardless of serologic results.
165
2 main Sx of chancroid?
1. Painful genital ulcer
| 2. Tender inguinal LAD, often suppurative
166
Describe presentation of LGV
Starts w/ genital papule or ulcer followed by a tender unilateral inguinal LAD
167
Describe genital warts
Painless, flesh-colored, exophytic lesions
168
Will Tx of genital warts prevent HPV transmission?
Nope
169
MC isolated cause of hematogenous osteomyelitis?
S. aureus
170
Which group of people would you worry about getting salmonella osteomyelitis?
Sickle cell
171
People with which high risk behavior are at higher risk of Pseudomonas osteomyelitis?
IVDU
172
What physical exam finding is pathognomonic for chronic osteomyelitis?
Draining sinus tract
173
How are xrays in the diagnosis of osteomyelitis?
Lack sens/spex
174
Best imaging technique for Dx osteomyelitis? Name 2 reasons why
MRI:
1. High sensitivity for bone infection
2. Superior at delineating bone anatomy and giving excellent resolution of surrounding soft tissue
175
Role of follow-up MRI in management of osteomyelitis?
Only for patients who don't clinically improve w/ therapy
176
Which cases of suspected osteomyelitis should get BCx?
All of them
177
Why should all cases of suspected osteomyelitis get BCx?
A positive BCx could avery more invasive testing
178
Gold standard for Dx of osteomyelitis?
Bone Bx
179
In suspected osteomyelitis, how do culture samples from soft tissue or sinus tracts correlate w/ deep Cx from bone?
Poorly
180
3 components of successful Tx of osteomyelitis?
1. Prolonged Abx
2. Surgical debridement
3. Removal of orthopedic hardware, if present
181
Is it ever okay to treat chronic osteomyelitis with PO Abx alone?
Apparently yes, in some cases
182
Findings that predict contiguous osteomyelitis in patients with diabetic foot ulcers? (5)
1. Ulcers that have been present for 2 wk or longer
2. Ulcer size greater than 2 cm
3. Grossly visible bone
4. Ability to probe to bone
5. ESR greater than 70
183
Best way to ID the offending bug in DM-associated osteomyelitis?
Debridement and culture of the sample before initiation of Abx
184
In DM-associated osteomyelitis, how long should you continue Abx s/p surgical debridement?
6 wk
185
What are some red flags that should prompt you to consider vertebral osteomyelitis? (6)
1. Worsening back or neck pain w/o an alternate explanation
2. Local tenderness
3. Sensory changes
4. Radicular pain
5. Motor weakness
6. Neurologic deficits
186
Approx what percent of patients w/ vertebral osteomyelitis have a fever at presentation?
50%
187
Approx what percent of patients w/ vertebral osteomyelitis will have positive BCx? Why is this important?
More than 50%
| Important bc they can help guide therapy and limit unnecessary testing
188
General duration of Abx therapy for vertebral osteomyelitis?
6-8 wk
189
3 major classes of causes of FUO?
1. Infection
2. Malignancy
3. Connective tissue disease
190
The longer a FUO persists w/o diagnosis, the less likely is is to be 2/2 ________? (Which one of the 3 major causes of FUO)
Infection
191
Although people with selective IgA deficiency can be ASx, they can also present with which two types of recurrent infections?
1. Sinopulmonary
| 2. GI
192
People with selective IgA deficiency have an increased risk of what 2 specific diseases and what 2 classes of disease?
1. IBD
2. Celiac disease
3. Allergic disorders
4. Autoimmune disorders
193
CVID typically manifests with what lab finding?
Hypogammaglobulinemia
194
CVID typically presents with involvement of what two organ systems? How does each manifest?
1. Respiratory: recurrent infections
| 2. GI: chronic diarrhea or malabsorption
195
2 findings that confirm CVID Dx?
1. Low levels of total IgG and IgA or IgM
| 2. Poor antibody response to vaccines
196
People with recurrent bloodstream infections with encapsulated bugs or invasive meningococcal or gonococcal disease should be screened for what immunodeficiency? What is the proper screening test?
Complement deficiency
| Assay for total hemolytic complement (CH50) activity
197
What larger issue should you suspect if you have a patient with inhalational anthrax?
Deliberate bioterrorism-related spread
198
7 potential Sx of inhalational anthrax?
1. Low-grade fever
2. Malaise
3. Myalgia
4. HA
5. Cough
6. Dyspnea
7. Chest pain
199
2 potential agents for post-exposure prophylaxis for inhalational anthrax?
Doxy or cipro
200
Why should a single case of suspected or confirmed smallpox cause concern for bioterrorism?
It has been eradicated worldwide
201
5 s/s of smallpox?
1. High fever
2. HA
3. Vomiting
4. Backache
5. Rash
202
Describe the rash of smallpox (both spread of lesions and progression of lesion characteristics)
Spread: start on buccal and pharyngeal mucosa, followed by cutaneous spread to the hands and face, then to arms, legs and feet.
Lesions: evolve synchronously from macules to papules to vesicles to pustules, then finally crust over.
203
4 presenting features of pneumonic plague?
1. Sudden high fever
2. Pleuritic chest discomfort
3. Productive cough
4. Hemoptysis
204
When do Sx of botulism typically occur after toxin exposure?
Within 24 to 72 hr
205
Classic triad of botulism presentation?
1. Symmetric descending paralysis w/ prominent bulbar signs
2. Absence of fever
3. Normal mental status
206
Bug causing tularemia?
Francisella tularensis
207
Tularemia presents with abrupt onset of (? 4 Sx) followed by what other type of Sx?
Starts with: fever, chills, myalgia, and anorexia
| Followed by: respiratory Sx
208
3 methods useful in diagnosis of tularemia?
1. PCR
2. Direct fluorescent stains of clinical specimens
3. IHC stains of clinical specimens
209
7 features of viral hemorrhagic fever presentation?
1. High febrile prodrome
2. Variable degrees of myalgia and prostration
3. Conjunctival injection
4. Petechial hemorrhages
5. Easy bruising
6. Flushing
7. Mild hypoTN
210
6 MC Sx of malaria?
1. Fever
2. HA
3. Myalgia
4. n/v
5. Abdominal pain
6. Diarrhea
211
Which type of malaria should be suspected in a pt w/ history of travel to Africa and a peripheral smear showing high levels of parasitemia w/ typical morphologic features?
Plasmodium falciparum
212
Incubation period of typhoid fever?
8-14 days
213
6 presenting features of typhoid fever?
1. Fever
2. HA
3. Arthralgia
4. Pharyngitis
5. Anorexia
6. Abdominal pain/tenderness
214
3 preferred Abx for typhoid fever?
1. Ceftriaxone
2. FQs
3. Azithro
215
Name 3 groups of people in whom Abx Ppx for travelers diarrhea should be considered?
1. IBD
2. Immunocompromised states
3. CMx that would be adversely affected by significant dehydration
216
Mainstay of Tx of travelers' diarrhea?
Fluid replacement
217
Effects of Abx on Tx of travelers' diarrhea, and when are they indicated?
Reduce duration of diarrhea by 1-2 days. Recommended only in severe dz
218
Dengue fever presents as an acute febrile illness potentially accompanied by a combo of what 5 features?
1. Frontal HA
2. Retro-orbital pain
3. Myalgia
4. Arthralgia
5. Minor spontaneous bleeding manifestations
219
Timing of hep A vaccine for travelers to endemic areas?
Give the initial vaccine one month before travel. Then give the booster 6-12 months later.
220
What option exists for travelers requiring HBV vaccinations but who have less than 6 months (recommended dosing schedule) before they leave?
Accelerated vaccination schedule
221
Rickettsial infection often presents with what 4 features?
1. Fever
2. HA
3. Malaise
4. Rash (maculopapular, vesicular, or petechial)
222
7 s/s of brucellosis?
1. Fever
2. Myalgia
3. Arthralgias
4. Fatigue
5. HA
6. Night sweats
7. Depression
223
Describe the natural progression of most cases of infectious diarrhea
Self-limited, resolving without directed intervention
224
General management of otherwise healthy patients with mild diarrhea who present w/ less than 72 hr of Sx?
Supportive Tx w/ no additional diagnostic evaluation or Abx
225
3 types of patients with acute diarrhea who require diagnostic testing (including stool Cx)?
1. Immunocompromised
2. Sick enough to require admission
3. Inflammatory diarrhea
226
If campylobacter is isolated in the stool of a patient with diarrhea, what further testing should you do?
In vitro susceptibility testing to guide Abx choices
227
If choosing to empirically treat a patient with suspected campylobacter diarrhea (controversial choice btw), what is the preferred antibiotic?
Macrolide
228
Empiric Tx of Shigella infection should be considered for which 2 groups of patients? Which patients should always get Tx for Shigella diarrhea?
Consider for: pts w/ compatible epidemiologic history or those w/ severe S
Always for those w/ positive stool Cx
229
Why should patients with culture-proven shigella diarrhea get Abx?
Reduces risk of secondary transmission
230
Name 2 reasons you shouldn't give Abx to otherwise healthy patients w/ mild symptoms of Salmonella diarrhea?
1. Doesn't hasten recovery
| 2. May cause prolonged ASx shedding of salmonella bacteria
231
Name 3 features that, if present in a patient w/ salmonella diarrhea, constitute severe salmonellosis
1. High fever
2. Sepsis
3. Hemodynamic instability
232
Benefits of Abx in patients w/ severe salmonellosis? (2)
1. Shorter duration of Sx
| 2. Decreases risk of extraintestinal spread
233
2 classes of medications that have been associated with increased risk of HUS when given to patients w/ Shiga toxin-producing E coli infection?
1. Abx
| 2. Anti-motility meds
234
What tissue is Yersinia trophic for? This can cause it to mimic what condition?
GI lymphoid tissue; appendicitis
235
A combo of which 2 risk factors puts patients at risk of severe Vibrio disease, specifically at risk of bloodstream infection with sepsis (which has a fatality rate close to 30%)?
Hepatic dysfxn + heavy EtOH use
236
Although enzyme immunoassays for C diff have good specificity, their sensitivity using a single stool sample is only _____?
75-85%
237
What test for C diff is being used more and more often because it's more sensitive than enzyme immunoassay?
PCR for toxins A and B
238
What 2 drugs are equally effective in Tx of mild-moderate C diff? Which one is preferred and why?
Flagyl and PO vanc
| Flagyl is preferred bc it's cheaper
239
What drug is preferred for first-line Tx of severe C diff?
PO vanc
240
What non-pharmacolgic treatment is effective in managing multiple relapses of C diff?
Fecal microbiota transplant
241
Describe effects of a fecal microbiota transplant on prevention of C diff in patients on Abx
It reduces risk for infection
242
Describe utility of documenting clearance of C diff via multiple stool samples?
Not useful
243
Most likely source of norovirus AGE?
Ingestion of contaminated food or water
244
Testing for parasites is not recommended for diarrhea lasting less than ______ or for patients who develop diarrhea more than ______ into a hospital stay
7 days; 3 days
245
Treatment of giardia with flagyl is curative in what percent of patients?
More than 85%
246
What is more sensitive for diagnosis of amebiasis: OPE or stool antigen testing?
Stool antigen testing
247
What group of patients is particularly susceptible to Cryptosporidium infection, which can lead to prolonged diarrhea, dehydration, and weight loss?
Immunocompromised patients, esp those w/ HIV/AIDS
248
DOC for symptomatic Cyclospoa infection?
TMP-SMX
249
Treatment for symptomatic Cyclospoa infection in patients w/ a sulfa allergy?
Cipro
250
In transplant patients, risk of specific infection varies ~predictably based on what 5 things?
1. Type of transplant
2. Donor and patient characteristics
3. Immunosuppressive regimen
4. Time since transplant
5. Post-transplant complications
251
Post-Tpx CMV infections can present in a lot of ways. Name 6
1. Non-specific febrile illness
2. Cytopenias, specifically thrombocytopenia and leukopenia
3. Pneumonitis
4. Hepatitis
5. Colitis
6. Esophagitis
252
What is the most significant consequence of EBV infection in a transplant patient?
Post-transplant lymphoproliferative disease
253
Proliferation of what cell line leads to post-transplant lymphoproliferative disease?
B cells
254
2 reasons that bacterial infections are common s/p solid-organ transplant? 1 reason they're common s/p HSCT?
Solid organ: surgical and nosocomial infections
| HSCT: neutropenia
255
Early-phase fungal disease in transplant patients is MC due to which two bugs?
1. Candida
| 2. Aspergillus
256
When is cryptococcus neoformans meningitis MC in transplant patients?
Later period
257
When is PCP MC in transplant patients?
Middle or late period
258
Infection prevention s/p transplant mainly relies on what 2 things?
1. Prophylactic antimicrobials
| 2. Immunizations
259
What type of immunization is typically CI in patients getting immunosuppression?
Live vaccines
260
Describe vaccine requirements in HSCT patients
They require revaccination with the complete series after immune system reconstitution, but live vaccines are CI
261
What percent of catheter-associated bloodstream infections and UTIs are thought to be preventable?
65-70%
262
What percent of VAP and surgical site infections are thought to be preventable?
55%
263
What is the cornerstone of preventing hospital-acquired infection?
Handwashing
264
Should you perform routine UA/UCx in patients w/ indwelling urinary catheters w/o s/s of UTI?
Nope
265
Which bug is MCC of surgical site infections?
Staph aureus
266
When you suspect a surgical site infection, what are 3 options of specimens to send for Cx?
1. Wound drainage material
2. Purulent fluid
3. Infected tissue
267
Treatment of deep incisional and organ or deep space surgical site infections generally requires a combination of what 2 things?
Specific antimicrobial therapy + surgical debridement
268
Describe benefit of continuing prophylactic antimicrobial agents post-op in preventing surgical site infections
No benefit
269
What should you suspect in patients w/ bacteremia and a central line with no obvious source of bacteremia (i.e. no infections at other sites)?
CLABSI
270
First two steps in treating a CLABSI?
First, remove infected central line. Next, start appropriate antibiotics
271
How often should you assess hospitalized patients with central lines to decide if the line can be removed?
Daily
272
First-line treatment for MSSA bacteremia? (2 options)
1. Nafcillin
| 2. 1st gen cephalosporin, like cefazolin
273
First-line treatment for MRSA bacteremia? (2 options)
1. Vanc
| 2. Dapto
274
Median time to clearance of MRSA bacteremia?
7-9 days
275
Most significant RF for hospital acquired PNA?
Intubation and mechanical ventilation
276
4 clinical findings of VAP
1. Temp greater than 38.0 C
2. Leukocytosis or leukopenia
3. Purulent sputum
4. Decrease in arterial oxygen saturation
277
Is there evidence for double-covering pseudomonas HAP/VAP?
Nope
278
If you have a patient with suspected HAP or VAP who doesn't improve w/ 72 hr of appropriate antimicrobial therapy, what are 3 things you should evaluate for?
1. Infectious complications
2. Alternate diagnosis
3. Another site of infection
279
Avoiding intubation is a great way to decrease the risk of HAP. What's a solid alternative to use, if feasible?
Non-invasive positive pressure ventilation
280
What are the 3 best ways to limit transmission of antimicrobial-resistant bugs in healthcare settings?
1. Full compliance with hand-washing protocols and contact precautions
2. Cleaning and disinfecting the environment and patient care equipment before it's used for another patient
3. Judicious use of antimicrobials
281
3 main ways HIV is transmitted?
Sexually, exposure to infected blood, perinatally
282
Dx of acute HIV infection requires detecting the virus by one of which two methods?
1. RNA PCR
| 2. p24 antigen testing
283
What two scenarios would cause you to diagnose an HIV patient as having AIDS?
1. Development of an AIDS-defining illness
| 2. CD4 drops below 200
284
Who should be screening for HIV?
Everyone from 13-65 yo
285
What is 4th gen HIV testing? How do you follow up a positive result?
Combo of HIV antibody immunoassay and a test for p24 antigen. If positive, follow with HIV-1/HIV-2 antibody differentiation immunoassay.
286
What are 2 important baseline studies to do in HIV patients to help guide initiation of therapy and to assess therapy response down the line?
1. Quant HIV RNA (viral load)
| 2. CD4 count
287
When can you stop monitoring T-cell subsets in HIV patients?
If they have persistently undetectable viral load, a normalized CD4 count, and if their therapy is stable.
288
How do risks of strep pneumo infection change in HIV patients, and what should you do about it?
They're at risk of invasive strep pneumo infections. Help by vaccinating with both the 13- and 23-valent pneumococcal vaccines.
289
In HIV/AIDS patients with a positive TB skin test or positive IFN-gamma release assay, what much you check before treating for latent TB or prophylaxing for MAC? What else do you also have to check if their CD4 is less than 50?
Must r/o active TB infection in all. If CD4 less than 50, also must r/o active MAC infection.
290
What are 3 metabolic complications associated with HIV infection and management?
1. DM
2. Hyperlipidemia
3. Glc intolerance
291
Why should all HIV patients be evaluated for active hep B and C?
Because co-infection is associated with increased risk of progression and worse prognosis
292
Interrupting HIV therapy is associated with what 2 major complications?
1. Increased CV events and death
| 2. Increased infectious complications
293
When does IRIS develop in HIV/AIDS patients (in relation to beginning anti-retroviral therapy), and what is it?
Develops in the first few months of initiating therapy. It occurs because the patient's reconstituted immune system has an intense inflammatory response to a preexisting infection (known or ASx)
294
In patients w/ untreated HIV, when do opportunistic infections usually start?
Once CD4 is less than 200
295
What is usually required for Dx of PCP?
Stains of BAL fluid
296
5 MC manifestations of CMV in AIDS?
1. Retinitis
2. Esophagitis
3. Colitis
4. Polyradiculitis
5. Encephalitis
297
Describe the lesions of Kaposi sarcoma in AIDS patients
Color varies from red to purple to brown. Potential morphology includes macules, papules, plaques, or nodules.
298
Which HIV patients get anti-retrovirals?
Whoever is ready to start, regardless of CD4
299
What is the most important principle in treatment of HIV?
The ARV regimen must fully suppress viral replication to prevent the development of viral drug resistance
300
How does viral load change with initiation of effective ARV treatment?
Viral load drops quickly and progressively within the first few wks of Tx, reaches undetectable levels within a few months, and remains undetectable as therapy continues,
301
Name two booster drugs used in HIV treatment. What is the point of a booster drug?
Cobicistat and ritonavir. Booster drugs inhibit the metabolism of other anti-retrovirals, leading to improved therapeutic drug levels and allowing less frequent dosing.
302
Describe the general recommendations for choosing an initial anti-retroviral treatment regimen.
Start with 3 drugs from 2 different classes, most commonly 2 NRTIs + either a protease inhibitor or an integrase inhibitor.
303
When should you do resistance testing as a part of HIV/AIDS management? (2)
When ARV therapy is initiated and when treatment failures occur
304
If performing resistance testing because of treatment failure in an HIV patient, when should you do it?
While the patient is still on the ineffective regimen
305
Which pregnant women should be tested for HIV?
All of them
306
Which HIV positive pregnant women should be given anti-retrovirals?
All of them- gotta reduce perinatal transmission
307
Post-exposure prophylaxis for HIV- when should you start it (in relation to exposure), how many drugs, and how long should you continue it?
Start ASAP, 3 drugs, treat for 4 wk
308
What is the FDA-approved regimen for HIV pre-exposure prophylaxis?
Once-daily combo pill of tenofovir-emtricitabine
309
Seasonal flu disproportionately affects what age group?
65 and older
310
4 groups of people predisposed to more severe flu infections?
1. Very old
2. Very young
3. Chronic medical conditions
4. Pregnant women
311
2 MC complications of the flu?
Primary influenza pneumonia and secondary bacterial pneumonia
312
During a confirmed local flu outbreak, how can you diagnose infection? Who should get confirmatory testing?
Diagnose on clinical criteria. Save confirmatory testing for pts at high risk of complications
313
Who should get the flu vaccine?
Everyone 6 months old or older
314
What are two drug options recommended for pts w/ confirmed or highly suspected flu who are at increased risk for complications?
Oseltamivir or zanamivir
315
Most effective intervention for preventing the flu?
Annual flu vaccine
316
What group of viruses causes SARS and MERS?
Novel RNA-containing coronaviruses
317
2 MC manifestations of primary HSV-1 infection?
Gingivostomatitis and pharyngitis
318
What virus is a very common cause of genital ulcer disease worldwide?
HSV2
319
3 drugs that are effective for treating episodic HSV infections and suppressing recurrent infections?
1. ACV
2. Val-ACV
3. Famciclovir
320
Name 4 benefits of starting either ACV, val-ACV or famciclovir within 72 hours of onset of VZV rash
1. Accelerate lesion resolution
2. Decrease new lesion formation
3. Decrease viral shedding
4. Lessen severity of acute zoster pain
321
What age group should get the zoster vaccine in order to reduce the incidence and severity of zoster and post-herpetic neuralgia?
Immunocompetent people 60 and older
322
MCC of infectious mono?
EBV
323
3 main clinical features of mono?
1. Exudative pharyngitis
2. Fever
3. LAD
324
Which patients with EBV need steroids?
Only those with complications of EBV like compromised airway or auto-immune hemolytic anemia. Regular old mono doesn't need steroids.
325
Most cases of CMV are ASx. When primary infection is symptomatic, how does it typically present?
As a mono-like syndrome
326
DOC in treatment of CMV reactivation in immunocompromised patients?
Ganciclovir
327
3 primary indications for daptomycin?
1. Gram positive complicated SSTI
2. Staph aureus bacteremia
3. Right-sided endocarditis
328
2 primary indications for telavancin?
1. Complicated SSTI caused by aerobic gram positive bugs (including MRSA)
2. Staph aureus HAP
329
What are two newly approved antibiotics for treatment of acute bacterial SSTI which can be dosed once weekly?
1. Dalbavancin
| 2. Oritavancin
330
Compare tedizolid (a new oxazolidinone) to linezolid? (3)
1. More potent
2. Active against linezolid-resistant staph aureus
3. Lower risk for thrombocytopenia
331
Name 3 highly resistant bugs that ceftaroline is active against.
1. MRSA
2. MDR Strep pneumo
3. Vanc-intermediate, linezolid-resistant, daptomycin-nonsusceptible strains of staph aureus
332
How does ceftaroline's gram negative activity compare to that of ceftriaxone?
About the same
333
Name 2 highly resistant bugs that ceftolozane-tazobactam is active against.
1. MDR pseudomonas
| 2. ESBL E. coli
334
When should you use tigecycline?
Only when alternate treatments aren't available
335
Describe spectrum of TMP-SMX
Broad aerobic, gram-positive, and gram negative activity
336
Is TMP-SMX active against CA MRSA?
Yup
337
What do you need to monitor in patients on colistin?
Renal function (it has dose-dependent nephrotoxicity)
338
Describe main usefulness of fosfomycin. What are two types of infections you should definitely not use it for?
Major use is in treatment of lower UTIs caused by VRE faecium and other MDR uropathogens. Don't use it for bacteremia or pyelonephritis.
339
You must monitor aminoglycoside serum levels to avoid which two dose-dependent toxicities?
Oto and nephrotoxicity
340
What style of aminoglycoside dosing creates less nephrotoxicity?
Extended-interval dosing
341
What is the most commonly used rifamycin?
Rifampin
342
Why isn't rifampin used as monotherapy?
Development of resistance
343
Describe bioavailability of rifampin
Excellent! It distributes widely through body tissues and fluids, even CSF
344
4 big negative effects of suboptimal use of anti-microbials?
1. Resistance
2. Poor outcomes
3. Increased costs
4. Increased ADE
