Infectious Disease - Academic Week Lecture Flashcards
(125 cards)
1
Q
What abx can you use to treat Staphylococcus aureus?
A
Clindamycin
Cloxacillin
Vancomycin
Cephalexin
*all have gram + coverage
2
Q
What pathogen causes Streptococcal pharyngitis?
A
Streptococcus progenies (Group A strep)
3
Q
A homeless person presents to the ER with a 3 month hx of recurrent, painful, self draining skin abscesses. What is the most likely pathogen?
A
MRSA
4
Q
“Grape like clusters”
A
Staphylococci
5
Q
“chains”
A
Streptococci
6
Q
Catalase +, coagulase + gram positive cocci
Catalase +, coagulase - gram positive cocci
A
S. aureus
S. epidermidis
7
Q
Catalase -, Beta hemolytic
A
S. pyrogens (GAS)
S. agalactiae (GBS)
8
Q
What infections are caused by Staphylococcus aureus?
A
SSTI: impetigo, cellulitis, folliculitis, furnaces, carbuncles
Pneumonia, pulmonary abscesses
Endocarditis, meningitis, joint/bone
9
Q
What toxin mediated reactions are caused by Staphylococcus aureus?
A
Food poisoning
Scalded Skin Syndrome
Toxic Shock Syndrome
10
Q
What antibiotics can be used to treat MSSA?
A
Cloxacillin Cefazolin (Ancef) Cephalexin (Reflex) Vancomycin Clindamycin
11
Q
What antibiotics can be used to treat MRSA?
A
Vancomycin TMP/SMX Clindamycin Linezolid Daptomycin
12
Q
What infections are caused by Group A Strep?
A
Pharyngitis
Impetigo
Erysipelas
Cellulitis
13
Q
What toxin mediated reactions are caused by Group A strep?
A
Necrotizing Fasciitis
Scarlet Fever
Toxic Shock Syndrome
14
Q
What immune mediated diseases are caused by Group A strep?
A
Glomerulonephritis
Rheumatic fever
15
Q
What is the treatment for Necrotizing Fasciitis?
A
Surgical debridement
IV Pen G
IV Clindamycin
IVIG
16
Q
What infections can be treated with Pen G?
A
The Big 3:
- Streptococci
- Neisseria meningitidis
- Treponema pallidum (syphilis)
Plus others (C Diff)
17
Q
What infections can be treated with ampicillin?
A
Pen G coverage +:
Enterococci, Listeria
H Flu
Ecoli, Proteus, Shigella, Salmonella
18
Q
What infections can be treated with Piperacillin?
A
Amp coverage +: Klebsiella, Sebratia, Enterobacter, Citrobacter Pseudomonas B. fragilis MSSA
19
Q
What infections can be treated with Cloxacillin?
A
Only covers gram +
MSSA (not MRSA)
S. Epidermis
Strep Species
(no gram neg-, no anaerobic)
20
Q
What bugs cause community acquired pneumonia (CAP)?
A
Streptococcus pneumonia (typical)
Chlamydia (atypicals)
Mycoplasma
Legionella
21
Q
What is used for out patient treatment of CAP (no modifying factors)?
A
Azithromycin
2nd line: doxy
22
Q
What is used for out patient treatment of CAP?
COPD, no steroids past 3 months
A
Azithromycin, clarithromycin
2nd line: doxy
23
Q
What is used for out patient treatment of CAP?
COPS, abs or steroids past 3 months
A
Levofloxacin, moxifloxacin
2nd line: amoxi/clav
24
Q
Are macrolides good drugs for in or out patient care?
A
Out patient
(bacterial static - bind to 50S ribosomal subunit inhibiting protein synthesis) … wouldn’t use for someone septic
25
What is Roseola infantum caused by?
Human herpesvirus 6 (HHV-6)
26
How do you treat Herpes Zoster infection?
Treat with antivirals within 72 hours of onset:
Acyclovir
Valacyclovir (Vatrex)
Famciclovir (Famvir)
27
If there are herpes zoster lesions on the tip of the nose, what do you have to worry about?
Corneal involvement
28
What causes athlete's foot?
Dermatophyte Trichophyton rubrum
29
Erythema infectious (fifth disease or slapped cheek disease) is caused by what
Human parvovirus B19
30
What viruses are DNA viruses?
```
All the Herpes viruses
HPV
ONLY Hep B
Pox viruses (i.e. molluscum)
Adenoviruses
Parvovirus B19
```
(rest are RNA - Hep A,C,E, etc)
31
A 12 year old boy presents with fever and bilateral parotid enlargement, the most likely diagnosis is:
MUMPS!
| note: patients need isolation, transmitted via droplet nuclei or direct contact
32
What is the Ontario MMR vaccination schedule?
12 months, 4-6 years
33
What viruses are most commonly involved in pharyngitis?
Adenovirus
34
X-ray lateral neck = thumbprint sign
Epiglottitis
35
What pathogens cause epiglottis?
Kids: H. influenza (more nontypel since vaccine); S. pneumonia
Adults: Group A Strep, H flu
36
What is the treatment for Epiglottis?
Maintain airway #1 concern
| Ceftriaxone or Cefotxime
37
8 year old boy presents to the ER with a maculopapular rash associated with some cough, coryza, fever 39.0
Koplik's spots on palate after day 3
Measles
38
What are complications of Measles?
```
Otitis media
blindness
pneumonia
diarrhea
encephalitis 1/1000
death 1/1000
```
39
What kind of bacteria is Bordetella pertussis?
Gram negative coccobacillus
40
What is the treatment for whooping cough?
Azithromycin or clarithromycin (up to 8 weeks into the cough)
41
Subcutaneous nodule at injury site with associated nodular lymphangitis which appears up to 6 months is seen in:
Sporotrichosis
| see spreading up lymphatics
42
Child age 4 presents with fever, unilateral ear pain, bulging tympanic membrane for 24 hrs. What is the #1 cause bacteria?
Streptococcus pneumoniae
43
Treatment for acute otitis media?
Amox or amoxi/clav
44
What is the most common cause of empyema?
Pneumococcus (streptococcus) pneumoniae
45
A 10 year old girl with a new kitten has a large tender lymph node under the right axilla, otherwise well. Dx?
Acute bartonella henselae infection
46
Pathogens for the following cat exposure diseases:
Cat scratch
Cat feces
Cat bite
Cat scratch = bartonella
Cat feces = toxoplasmosis
Cat bite = pasturella
47
An HIV + patient presents with dysphagia and thrush
Oral-esophageal candidiasis
48
What is the txt for oral-esophageal candidiasis?
Oral fluconazole
49
At what CD 4cell count do you start prophylaxis against Pneumocystis jiroveci (carinii) in HIV patients?
200 cells/ml
50
What drug is used for prophylaxis against pneumocystis jiroveci (carinii) in HIV infected patients?
Trimethoprim sulfamethoxozole
51
When should antiretroviral medication begin in asymptomatic HIV patients at? (CD4 count)
ANY CD4 count
| old cut off was 500 cells/ml
52
A 37 to male IV drug user presents to the ER. The nurse attending suffers a needlestick injury from the patient. Which infection carries a risk of 0.3% overall risk?
HIV
53
What is the risk of perinatal HIV transmission in untreated HIV + women?
25% overall risk
54
What is the risk of perinatal HIV transmission in treated HIV + women, stating antiretroviral therapy at 14 weeks gestation, compliant with therapy, and maintains an "undetectable viral load"?
<1%
55
What is the current antiretroviral treatment standard?
3 drugs one pill/day regimen
Ex: Tenofovir + FTC + Elvitegravir
56
How do you determine the prognosis for HIV infected patients?
CD4 lymphocyte count and HIV viral load (RNA load)
57
A 34 year old returns from Zaire Africa 4 days ago with new onset fever, sweats, fatigue. What is your course of action?
Typhoid fever is possible and therefore he needs blood cultures
58
What common pathogens cause Traveller's diarrhea?
E coli, Salmonella, Cholera
59
What antimicrobial agent causes tendinopathy?
Fluoroquinolones
60
What is the difference in coverage between cipro, levo, and moxi?
Cipro - excellent gram neg + pseudomonas
Levo - gram neg-, gram + and atypical
Moxi - levo + anaerobic
61
A 67 yo diabetic patient is treated with gentamicin, ceftazidime, and metronidazole for a gangrenous foot infection. She develops acute renal failure 2 weeks into treatment. Why?
Amino glycoside nephrotoxicity
62
An elderly women is readmitted to the hospital with frequent loose diarrhea after being hospitalized for pneumonia. What is the most likely cause?
Clostridium difficile
63
Pseudomembranous colitis is caused by:
Clostridium difficile
64
Clostridium difficile infection is best treated with
Metronidazole orally
65
Elderly woman is treated with oral metronidazole for her C Diff and relapses with diarrhea. She presented several times to a walk in over 3 month period and was given repeat courses of metronidazole. What is she complaining of now?
Sensory neuropathy
66
What can you give besides metronidazole for relapsing c diff?
Vanco
67
A 27 yo female has an ESBL E coli urinary tract infection. What does this mean?
ESBL: extended spectrum beta-lactamase producing
Organism is resistant to cephalosporins
68
What is the most common cause of peritonsillar cellulitis or abscess?
Beta hemolytic streptococci
69
What is the most common cause of Ludwig's angina?
Group A streptococci + anaerobes
70
How do you treat Ludwig's angina?
Pen G + metronidazole or clinda
71
27 year old female presents to ER with a 2 day hx of fever, flank pain, dysuria. Dx?
Pyelonephritis
72
What is the number one cause of pyelonephritis?
E. Coli
73
How many days of abx are required for uncomplicated cystitis?
3 days
74
What are the organisms that cause acute pyelonephritis?
```
KEEPS
Klebsiella
E coli
Enterococcus
Proteus
S saphrophyticus
```
75
What is the treatment for acute pyelonephritis?
14 days TMP/SMX or 3rd gen ceph or FQ
76
List Gram Negative Bacilli
```
Enterobacter (GI tract):
E coli
Shigella
Salmonella
Citrobacter
Klebsiella
Yersinia
Proteus
Morganella
Serrate
Enterobacter
```
H Flu
Pseudomonas
Legionella
etc.
77
What antibiotics cover PSEUDOMONAS
```
Cirpo (only oral agent)
Aminoglycosides (tobramycin, gent)
Ceftazidime / Cefipime
Pip/tazo
Meropenum
Imipenem
```
78
What antibiotics cover ANAEROBICs:
```
Metronidazole
Clindamycin
Moxiflox
Amax/Clav (clavulin)
Cefoxitin/ Cefotetan
Pip/tazo
Meropenum
Imipenum
```
79
Does a positive mantoux test mean a patient has active TB?
no
80
Isoniazid hepatotoxicity occurs in what percentage of patients?
1-2% of patients in general
| 2% over the age of 50
81
What are the side effects of Isoniazid?
Central nervous system too
Peripheral neuropathy
Hepatotoxicity
Jaundice/ skin rash
82
What is the overall lifetime risk of developing reactivated TB in a patient with untreated latent TB?
5-10%
83
A hospitalized patient with active pulmonary TB and coughing requires which infection control measure?
Negative pressure ventilation
84
What is the difference in treatment between active and latent TB?
Latent: Isoniazid (INH) + Vit B6 x 9 months
Active: add
Rifampin x 9-12 mo
Pyrazinmide x 2 mo
85
A 26 yo female reports vaginal discharge and lower abdominal pain over the last few days. Examination reveals much-purulent endocervical discharge and gram stain revealing NO organisms. Dx?
Chlamydia trachomatis (doesn't gram stain, lives IN cells)
86
What is the best way to dx syphilis?
Serologically
87
A 22 yo sexually active male presents with urethral discharge and a urine specimen for N gonorrhoea by NAAT is +.
Treatment?
Ceftriaxone 250mg IM x 2dose + Azithro 1 gm PO X 1 dose
88
Txt for chlamydia
Doxy 100mg PO BID x 7 days
or
Azithro 1gm PO x1
89
Txt for HPV
Imiquimod 3x/wk
Cryotherapy
Excision/ laser
90
Txt for treponema pallidum
Benzathine Penicillin
91
Txt Herpes
Acyclovir 200 mg 5x/d for 5 days
92
With virus is associated with a hepatoma?
HBV
93
Close personal contacts of patients with HEP A should receive:
Gamma globulin
94
Hep A serologies
HAV IgM
| HAV IgG
95
Hep C serologies
Hep C AB
Chronically determined by further testing for Hep C RNA level
96
Hep B serologies
Hep B AB = past infection or immunization
Anti-Hbc = IgM + (acute infection)
= IgG + (past infection)
```
HBsAg = acute HBV or chronic carrier
HBeAg = chronic active Hep B
```
97
A patient presents with diffuse erythema, pain, and warmth of the lower leg with associated intermittent fever. Txt?
Want to cover Gram + (staph and strep)
IV Cefazolin
98
Skin and soft tissue infection:
Txt for mild, uncomplicated
Cloxacillin, cephazolin, or clinda (pen allergy)
99
SSTI in diabetic
Add gram neg and anaerobic coverage
100
SSTI in IV drug use
MRSA (vanco)
101
SSTI nec fasc
Cephazolin or Pen + Clinda
102
An 18 yo previously healthy male presents to ER with a one day hx of headache, fever, photophobia. Empiric txt for bacterial meningitis?
IV Ceftriaxone
103
Meningitis: gram+ diplococci
Streptococcus pneumo
104
Meningitis: gram neg- diplococci
N. meningitidis
105
What drug should you add if you suspect Listeria in meningitis?
Ampicillin IV
106
Organisms for acute meningitis in neonates and <2mon
Ecoli
GBS
Listeria
107
Organisms for acute meningitis < 10yrs
Viral
H flu
S pneumo
Meningococci
108
Organisms for acute meningitis in adults
Viral
S pneumo
Meningococci
109
Organisms for acute meningitis elderly
S pneumo
Gram neg- baci
Listeria
110
A 50 yo male presents with sudden onset of non bloody watery diarrhea 5 days after returning home from Mexico. dx?
Enterotoxigenic E. Coli
#1 cause of travellers diarrhea
111
Treatment for Enterotoxigenic E. Coli
Levofloxacin
Ciprofloxacin
TMP/SMX
112
IF travellers diarrhea lasts >14 days consider
Protozoa
113
What organisms cause bloody diarrhea (invasive, inflam)
```
Campylobacter jejuni
Shigella
Salmonella sp
Yersinia
E Coli 0157:H7
```
114
What organisms cause non bloody diarrhea
Enterotoxigenic E Coli
Vibrio cholera
S aureus
C Diff
115
What are parasitic causes of diarrhea?
```
Entamoeba histolytic (amebiasis)
txt with metronidazole/ iodoquinol if invasive (liver abscess)
```
```
Guardia lamblia (bever fever)
txt with metronidazole
```
Cryptosporidium
txt supportive
116
What viruses cause diarrhea?
Rotavirus
| Norovirus
117
A 2yo female presents with vaginal and perianal pruritis over the last 1 week. Symptoms are transient and usually nocturnal. Dx?
Enterobius vermicularis (pinworms)
118
A 45 yo male from Northern Ontario was investigated for vague RUQ and RLL discomfort. CXR revealed a multiloculated just in the right lower lung and abdo u/s revealed a large cast with septate internal structures. The patient has extensive involvement with wild animals and dogs. Dx?
Echinococcus granulosus
| dog pinworm - makes cysts in liver, lungs
119
A 60yo male with long standing OA of his knees presents with an acutely inflamed, swollen, painful right knee with difficulty weight bearing. Septic arthritis - what is the route of infection?
Hematogenous
120
Common causes of septic arthritis?
S. aureus
| N. gonorrhoea (75% in sexually active)
121
How do you make the dx of septic arthritis?
Arthrocentisis
122
Txt for septic arthritis?
Ceftriaxone + Clinda (empiric) min 4 weeks if native joint
123
Erythema chronicum migrant is associated with
Lyme disease
124
How do you dx Lyme disease
serology
125
Txt Lyme disease
Stage 1: Doxy 21 days
Stage 2,3: Ceftriaxone 2-4 weeks
