Bacterial Infections Flashcards
1
Q
How are perioperative ABX administered?
A
Pre-operative: infuse cefazolin/cefuroxime within 60 min before 1st incision; infuse quinolone/vanco 120 min before 1st incision
Perioperative: longer surgeries >4 hours or major blood loss
Post-operative: D/C ABX within 24 hours
2
Q
Which ABX is preferred for cardiac/vascular surgeries and what is an alternative?
A
Cefazolin/cefuroxime
Alternative for beta-lactam allergy: Clindamycin or Vanco
3
Q
Which ABX is preferred for orthopedic (joint replacement/hip fracture) surgeries and what is an alternative?
A
Cefazolin
Alternative for beta-lactam allergy: Clindamycin or Vanco
4
Q
What ABX is preferred for GI surgeries (apendectomy, colorectal)?
A
Cefazolin + metronidazole, cefotetan, cefoxitin, or Unasyn (all cover B.fragilis anerobe)
Alternative for beta-lactam allergy: clindamycin/metronidazole + aminoglycoside/quinolone
5
Q
What are s/sx of meningitis?
A
- fever
- headache
- nuchal rigidity (stiff neck)
- altered mental status
6
Q
What microbes are common causes of mengingitis?
A
- Neisseria meningitidis
- Streptococcus pneumoniae
- Haemophilus influenzae
- Listeria monocytogenes (neonates,
age>50, immunocompromised patients)
7
Q
What is empiric treatment of meningitis in neonates <1 month?
A
Ampicillin (Listeria) +
Cefotaxime, ceftazidime, cefipime
+/- Gentamicin
* DO NOT use ceftriaxone in neonates causes biliary sludging (solids precipitate from bile) and kernicterus (brain damage from high bilirubin)
8
Q
What is empiric treatment of meningitis in ages 1 month to 50 years?
A
Ceftriaxone + Vancomycin (double coverage of Strep)
9
Q
What is the empiric treatment of meningitis in immunocompromised and aged>50?
A
Ampicillin (Listeria) + Ceftriaxone + Vancomycin (2x strep coverage)
10
Q
What are s/sx of acute otitis media (AOM)?
A
- Buldging tympanic (eardrum) membranes
- Otorrhea (middle ear effusion/fluid)
- Otalgia (ear pain)
- Tuuging/rubbing of ears
- fever
- crying
11
Q
What bacteria commonly cause acute otitis media?
A
- S. pneumoniae
- H. influenzae
- Moraxella catarrhalis
12
Q
When should observation of AOM be considered?
A
Age <6 months: always treat with ABX
Age 6-23 months: symptoms in 1 ear only and non severe symptoms
Age ≥ 2y: non severe symptoms in 1 or both ears
Observe for 2-3 days if otalgia <48 hours, no otorrhea, temp <102.2
If symptoms do not improve or worsen, use ABX
13
Q
What are first-line and alternative agents used to treat AOM?
A
- Amoxicillin 90mg/kg/day divided in 2 doses or Amoxicillin/Clavulanate 6.4 mg/kg/day in 2 divided doses
Preferred agent: Augmentin ES-600 (600mg amox/42.9mg clav) - mild-PCN allergy: Cefdinir 14mg/kg/day 1-2 divided doses OR other 2nd/3rd gen cephalosporin
14
Q
What agents are used for treatment failure of AOM (not improved within 2-3 days)?
A
- if amoxicillin used use Augmentin
- Ceftriaxone 50mg/kg IM QD x 3 days
15
Q
What are s/sx of the common cold (common respiratory viruses)?
A
- Sneezing
- Runny nose
- Mild sore throat
- Cough
- congestion
16
Q
What are s/sx of influenza?
A
- Sudden onset fever
- Chills
- Fatigue
- Myalgia
- dry cough
- sore throat
- headache
17
Q
What are s/sx of pharyngitis (repiraotry virus, S. gyogenes-GAS) ?
A
- Sore throat
- Fever
- Swollen lymph nodes
- White patches (exudates) on the tonsils
18
Q
What testing should be done with symptoms of pharyngitis?
A
rapid antigen test for “strep throat”
19
Q
What are 1st line treatments for S. pyogenes (strep throat)?
A
- Penicillin/Amoxicillin
- mild allergy: 1st/2nd gen cephalosporin
- severe allergy: macrolide/clindamycin
20
Q
What are s/sx of acute sinusitis (S. pneimoniea, H. influenzae, M.catarrhalis)?
A
- Nasal congestion
- Purulent nasal discharge
- Facial/ear/dental pain/pressure
- Headache
- Ffver
21
Q
When should someone get antibiotics with s/sx of acute sinusitis?
A
- ≥10 days of persistant sx
- ≥3 days of severe sx (face pain, purulent discharge, TEMP >102)
- worsening of sx after improvement
22
Q
What are 1st line ABX for acute sinusitis (S. pneimoniea, H. influenzae, M.catarrhalis)?
A
Augmentin
23
Q
What are s/sx of acute bronchitis?
A
non-productive/productive cough lasting 1-3 weeks; chest X-ray is normal
24
Q
What ABX are used for acute bronchitis?
A
Not recommended not usually bacterial; supportive care
25
What s/sx of a COPD exacerbation require ABX?
Any 1 of the following:
1. increased dyspnea, sputum volume, and sputum purulence (must have all 3)
2. increased sputum purulence (yellow/green) + 1 other symptom
3. Mechanically ventilated
26
What ABX are preferred for COPD exacerbation (S. pneimoniea, H. influenzae, M.catarrhalis)?
1. Amoxicillin/ clavulanate
2. azithromycin
3. doxy
4. respiratory quinolone
27
What are preferred ABX for whooping cough (Bordatella pertussis)?
Macrolides (Azithromycin, clarithromycin)
28
What are s/sx of CAP?
1. SOB
2. Fever
3. Cough with purulent sputum
4. Rales (cracking in the lungs)
5. Tachypnea (increased respiratory rate)
6. pleuritic chest pain
7. decreased breath sounds
29
How is CAP diagnosed?
Gold standard: chest x-ray with "infiltrates", "opacities", "consolidations"
30
What are most likely bacterial causes of CAP?
1. S. pneumoniae
2. H. influenzae
3. M.catarrhalis
4. C. pneumoniae
31
What is the usual treatment duration for CAP?
5-7 days
32
What is the preferred treatment of outpatient CAP in healthy patients (no comorbidities)?
1. Amoxicillin (1g TID)
2. Doxy
3. macrolide if resistance <25%
33
What is the preferred treatment of outpatient CAP in high risk patients (chronic heart disease, lung/liver/renal disease, DM, alcohol use disorder, malignancy, asplenia)?
1. beta-lactam (augmentin/cephalosporin preferred) + macrolide/doxy
2. respiratory quinolone
34
What is preferred treatment for
non severe inpatient CAP?
1. Ceftriaxone, Unasyn, or other beta-lactam + macrolide/ doxycycline
2. Add vanco if MRSA coverage is needed
3. If pseudomonas coverage needed use Zosyn, cefepime, meropenem
35
What is the preferred treatment for in patient CAP treatment in ICU patients?
1. beta-lactam+ macrolide
2. beta-lactam+ respiratory quinolone (do not use quinolone monotherapy)
3. Add vanco if MRSA coverage is needed
4. If pseudomonas coverage needed use Zosyn, cefepime, meropenem
36
When would coverage for both MRSA and pseudomonas be necessary?
hospitalization and use of parenteral ABX within the past 90 days
37
What is HAP?
onset >48 hours after hospital admission
38
What is VAP?
onset >48 hours after the start of mechanical ventilation
39
What are risk factors for MRSA?
1. IV ABX use within the past 90 days
2. MRSA prevalence >20% in the hospital unit or unknown
3. prior MRSA infection
4. positive MRSA nasal swab
40
What are risk factors for MDR grm neg pathogens?
1. IV ABX use in the past 90 days
2. prevalence of gram neg resistance in hospital unit >10 %
3. hospitalized ≥ 5 days prior to the onset of VAP
41
What are preferred regimens for HAP/VAP?
1. ALL need MSSA and pseudomonas:
Cefepime/Zosyn/Levofloxacin
2. If at risk for MRSA:
vanco/linezolid
3. If at risk for MDR gram neg:
add a 2nd antipseudomonal (aztreonam, aminoglycoside, levo/cipro)
42
What bacteria causes TB?
Mycobacterium tuberculosis; anaerobic, non-spore forming bacillus
43
How is TB transmitted?
highly contagious aerosolized droplets during active pulmonary TB
44
What is latent TB?
Symptoms are not present and contained by the immune system; not contagious but can advance to active
45
What are s/sx of TB?
1. Cough/ hemoptysis (coughing up blood)
2. Fever
3. Night sweats
4. purulent sputum
5. unintentional weight loss
46
What precautions are taken with active TB?
1. patient isolation in a single-negative pressure room
2. healthcare workers must wear a respirator mask
47
How is latent TB diagnosed?
1. tuberculin skin test (TST/PPD) injected intradermally and inspected for induration (raised area) 48-72 hours later
2. interferon-gamma release assay IGRA
3. chest x-ray
48
What indurations are the criteria for positive TST?
≥5mm: HIV, Immunosuppression, close contact with recent active TB
≥10mm: high risk congregate settings (prisons, healthcare facilities, homeless shelters), clinical risk (IV drug use, DM)
≥15mm: no risk factors
49
What will cause a false positive TST test?
hx of bacille Calmette-Guerin, BCG vaccination (used in countries with high TB rates)
50
What is the preferred duration of latent TB treatment?
shorter regimens (3-4 months preferred)
51
What are preferred regimens for latent TB?
1. Isoniazid (INH) + rifapentine weekly x 12 weeks via DOT (directly observed therapy)
2. INH + rifampin daily X 3 months
3. Rifampin 600mg QD x 4 months
4. INH 300mg QD X 6-9 months (Preferred in HIV-positive patients x 9 months)
52
How is active TB diagnosed?
1. Acid-fast bacilli AFB smear and culture of sputum sample (may take up to 6 weeks, slow growing)
2. chest x ray showing consolidation or cavitation
53
How is active TB treated?
1. intensive phase: RIPE x 8 weeks (until cultures and sensitivities available)
2. continuation phase: 2 drugs x 4 months (usually INH + rifampin) but base on culture/sensibilities
54
What are CIs with Rifampin?
DO NOT use with protease inhibitors
55
What are SEs with Rifampin?
1. Orange-red coloring of body secretions (Saliva, Sweat, Urine, Tears); can stain Contact lenses, Clothing, and bedsheets
2. elevated LFTs
3. Hemolytic anemia (+ Coombs test)
4. flu-like syndrome
5. GI upset
6. rash/pruritis
56
Which drug can replace rifampin if needed due to DIs?
Rifabutin
57
Rifampin
Rifadin
58
What are boxed warnings with isoniazid (INH)?
Severe and fatal Hepatitis
59
What are CIs with Isoniazid?
1. active liver disease
2. previous severe adverse reaction
60
What are the warnings with isoniazid?
1. Peripheral neuropathy
2. Pyridoxine (B6) supplementation is recommended in pregnancy/breastfeeding
61
What is dosing of pyridoxine (B6) to prevent INH-induced peripheral neuropathy?
25-50mg PO Qd
62
What are SEs with Isoniazid?
1. Elevated LFTs (usually asymptomatic)
2. Drug-induced lupus erythematosus
3. Hemolytic anemia (+ Coombs)
4. agranulocytosis
5. aplastic anemia
6. hyperglycemia
7. headache
8. GI upset
9. pancreatitis
10. severe skin reactions (SJS/DRESS)
11. optic neuritis
63
What are CIs with Pyrazinamide?
1. Acute gout
2. severe hepatic damage
64
What are SEs with Pyrazinamide?
1. Elevated LFTs
2. Hyperuriciemia/gout
3. Gi upset
4. malaise
5. arthralgia
6. myalgia
7. rash
65
What are CIs with Ethambutol?
1. optic neuritis (benefit>risk)
2. young children
3. unconscious patients
4. patients that cannot report/discern visual changes
66
What are SEs with Ethambutol?
1. Elevated LFTs
2. Optic neuritis (dose-related)
3. Confusion
4. Hallucinations
5. decreased visual acuity
6. partial loss of vision/blind spot/ color blindness (usually reversible)
7. rash
8. headache
9. N/V
67
What is RIPE therapy?
Rifampin (empty stomach)
Isoniazid (empty stomach)
Pyrazinamide
Ethambutol (Myambutol)
68
What drugs interact with Rifampin?
Decreases the concentrations of:
Protease inhibitors
Warfarin-very large decrease INR
Oral contraceptives-decrease effectiveness
Don't use with:
apixaban/rivaroxaban/edoxaban/ dabigatran
69
How is endocarditis diagnosed?
1. Echocardiogram with visible vegetation
2. Positive blood cultures
70
How is gentamicin dosed for gram pos synergy for endocarditis?
Peak levels: 3-4 mcg/mL
Trough levels: <1 mcg/mL
71
What is the usual treatment of duration for endocarditis?
4-6 weeks of IV aBX
72
What is the preferred treatment for endocarditis caused by Virdans group streptococci?
Penicillin/Ceftriaxone +/- gentamicin
beta-lactam allergy: Vanco monotherapy
73
What is the preferred treatment for endocarditis caused by MSSA?
Nafcillin/Cefazolin/Vanco + gentamicin and rifampin if prosthetic heart valve
74
What is the preferred treatment for endocarditis caused by MRSA?
Vanco + gentamicin and rifampin if prosthetic heart valve
75
What ABX are used to prevent endocarditis during dental procedures?
1. Amoxicillin 2g PO
2. Azythromicin 500mg
3. Clrythromicin 500mg
4. Doxycycline 100mg
Used as a single dose 30-60 minutes before the dental procedure
75
What are common clinical intra-abdominal infections?
1. Appendicitis
2. Cholecystitis (acute inflammation of the gallbladder due to obstructive stone)
3. Cholangitis (infection of common bile duct
4. Secondary peritonitis
5. Diverticulitis
75
What is spontaneous bacterial peritonitis?
infection of the peritoneal space that often occurs in patients with cirrhosis and ascites
75
What conditions put a patient at high risk of infective endocarditis during a dental procedure?
1. Artificial (prosthetic)heart valve or valve repair with artificial material
2. History of endocarditis
3. Heart transplant with abnormal heart valve function
4. Certain congenital heart defects including heart/heart valse disease
76
How is SBP diagnosed?
fluid sample during paracentesis ≥250 PMNs (polymorphonuclear leukocytes)
76
What is the preferred treatment for endocarditis caused by enterococci?
1. penicillin/ampicillin + gentamicin
2. ampicillin + high dose ceftriaxone
3. vanco (allergy) + gentamicin
4. VRE: daptomycin/linezolid
76
What agents are used for secondary prophylaxis of SBP?
1. SMX/TMP
2. Cipro
76
What is the empiric treatment for SBP?
ceftriaxone x 5-7 days
77
What pathogens should be covered for intrabdominal infections?
1. streptococci
2. enteric gram neg (PEK)
3. anaerobes (B.fragilis)
78
What are treatment options for community-acquired intra-abdominal infections?
1. ertapenem
2. moxifloxacin
3. cefuroxime/ceftriaxone + metronidazole
4. cipro/levo + metronidazole
79
What are treatment options for patients at risk of resistant or nosocomial pathogens?
1. carbapenem (not ertapenem)
2. Zosyn +/-ampicillin/vanco if enterococcus/MRSA coverage is needed
3. Cefepime/ceftazidime + metronidazole +/-ampicillin/vanco if enterococcus/MRSA coverage is needed
80
What is a mild, moderate, and severe SSTI?
Mild: no systemic signs
Moderate: systemic signs (temp >100.4, HR>90, WBC>12,000 or <4000)
Severe: systemic signs + signs of a deeper infection (fluid-filled blister, skin sloughing, hypotension, evidence of organ dysfunction), immunocompromised, or failed PO ABX + incision and drainage
81
What microbes commonly cause SSTIs?
1. S. aureus
2. Streptococci (S.pyogenes)
3. MRSA
82
How does impetigo present?
blister-like rash that forms honey-colored crusts over ruptures pustules around the nose, mouth, hands, arms
83
What are outpatient treatments for impetigo?
Localized infections:
1. Topical mupirocin
2. retapamulin (Altabax)/ ozenoxacin (Xepi)
Numerous/invasive lesions:
1. Cephalexin
2. dicloxacillin
84
What are outpatient treatments for folliculitis/furuncle/ carbuncle?
1. SMX.TMP
2. Doxy
85
What are outpatient treatments for non-purulent cellulitis?
1. Cephalexin 500mg PO QID
2. dicloxacillin
3. clindamycin
86
What are out patients treatments for purulent cellulitis?
1. SMX/TMP
2. Doxy
3. clindamycin
4. linezolid
87
What are treatments for severe purulent cellulitis?
1. Vanco (trough 10-15)
2. Daptomycin
3. Linezolid
7-14 days total therapy
88
What are empiric treatments for necrotizing fascitis (severe nonpurulent)?
Vancomycin/Daptomycin + beta-lactam (zosyn/carbapenem) + clindamycin (to supress streptococcus toxin production)
89
What are treatment regimens for diabetic foot infections without MRSA activity?
1. Unasyn
2. Ertapenem
3. Ceftriaxone
4. Levo/moxi
90
What are treatment regimens for diabetic foot infections with psudomonas or MDR gm neg risk?
1. Zosyn
2. Cefepime
3. Meropenem, doripenem, imipenem/cilastatin
91
What are treatment regimens for diabetic foot infections when anerobic activity is needed?
add metronidazole or use beta-lactam with anaerobic activity
92
What is aute cyctitis?
lower UTI infection affecting bladder/urethra
93
What is pyelonephritis?
upper UTI affecting kidneys
94
What can aid in the diagnosis of UTI?
Urinalysis:
1. pyuria (WBC>10)
2. bacteria
3. positive leukocyte esterase/ nitrates
Urine culture
95
What are symptoms of cystitis?
1. frequency/urgency/ nocturia
2. Dysuria (painful urination)
3. Suprapubic tenderness
4. Hematuria (blood in urine)
96
What are sx of pyelonephritis?
1. Flank pain
2. abdominal pain/ N/V
3. fever/chills/mailaise
97
What are preferred treatments for acute systitis?
1. Nitrofurantoin (Macrobid) 100mg PO BID x 5 days (CI if CrCl<60)
2. SMX/TMP DS 1 tablet PO BID x 3 days (CI sulfa allergy)
3. Fosfomycin 3g x 1 dose
98
What are preferred treatments for acute systitis in pregnancy?
1. Amoxicillin
2. Cephalexin
99
What are treatments for outpatient pyelonephritis?
If local quinilone resistance ≤10%:
1. Cipro 500mg PO BID x 5-7 days
2. Levofloxacin 750mg PO QD x 5-7 days
If quinolone resistance >10%:
1. Ceftriaxone 1g IV/IM x 1, ertapenem 1g IV/IM x 1, aminoglycoside extended interval IV/IM x1 THEN continue with a quinolone for 5-7 days
100
What are treatments for inpatient pyelonephritis?
Initial: Centriaxone/quinolone
Concern for resistance: Carbapnem for ESBL-producing, Zosyn
5-10 days
101
What medication can help with pain/burning with urination (does not treat infection)?
Phenazopyridine (Pyridium, Azo Urinary Pain Relief)
102
What are counseling points with Phenazopyridine (Pyridium, Azo Urinary Pain Relief)?
1. only use for a max of 2 days
2. take with 8 oz of water
3. take with it immediately following food to minimize stomach upset
4. can cause red-orange coloring of the urine and other body fluids; contact lenses/clothes can be stained
103
What are CIs with Phenazopyridine (Pyridium, Azo Urinary Pain Relief)?
Do not use in renal impairment or liver disease
104
What are SEs with Phenazopyridine (Pyridium, Azo Urinary Pain Relief)?
1. headache
2. dizziness
3. stomach cramps
4. body secretion discoloration
105
When must asymptomatic bacteriuria be treated?
pregnancy ≥ 10^5 bacteria/mL of UA
106
What are the preferred agents for bacteriuria in pregnancy?
amoxicillin +/- clavulanate or an oral cephalosporin
107
Why should quinolones not be used in pregnancy?
cartilage toxicity and arthropathies
108
What are s/sx on C.diff
1. ≥ 3 watery stools/day
2. abdominal cramps
3. fever
4. elevated WBCs
109
What are risk factors for developing C.diff?
1. healthcare exposure
2. PPIs
3. advanced age
4. immunocompromised
5. previous infection
110
What is the MOA of Bezlotoxumab (Zinplava)?
antibody that binds to toxin B and neutralizes its adverse effects; decreases recurrence but does not treat infection (adjunct only)
111
What are preferred treatments for the 1st episode of C.diff?
1. Fidaxomicin 200mg PO BID x 10 days
2. Vaco 125mg PO QID x 10 days
3. Metronidazole 500mg TID x 10 days (only if nonsevere and other treatments unavailable)
112
What are preferred treatments of C.diff for the 2nd episode (1st recurrence)?
1. Fidaxomicin 200mg PO BID x 10 days
2. Vaco 125mg PO QID x 10 days followed by a prolonged pulse/taper regimen- BID x 1 week then QD x 1 week then every 2-3 days for 2-8 weeks (unless metronidazole was used)
113
What are preferred treatments for C.diff for the 3rd or subsequent episodes?
1. Fidaxomicin 200mg PO BID x 10 days
2. Vaco 125mg PO QID x 10 days followed by a prolonged pulse/taper regimen
3. Vanco 125mg PO QID x 10 days then rifaximin 400.g TID x 20 days
4. fecal microbe transplant
114
What is the preferred treatment for fulminant/complicated C.diff (hypotension, shock, ileus, toxic megacolon)?
Vanco 500mg PO /NG/PR QID + metronidazole 500mg IV Q8H
115
What are symptoms of chlamydia?
genital discharge or no symptoms
116
What are symptoms of gonorrhea?
genital discharge or no symptoms
117
What are symptoms of latent syphilis?
asymptomatic
118
What are symptoms of primary syphilis?
painless, smooth genital sores (chancre)
119
What are symptoms of bacterial vaginosis?
1. vaginal discharge (clear, white, grey)
2. fishy odor
3. pH> 4.5
4. little/no pain
120
What are symptoms of trichomoniasis?
1. yellow/green frothy vaginal discharge
2. pH >4.5
3. soreness/pain with intercourse
121
What is the preferred treatment for syphilis acquired within the past year?
Bicillin L-A (penicillin G benzathine) 2.4 million units IM x 1
122
What are alternative treatments for syphilis acquired within the past year?
1. Doxy 100mg PO BID x 14 days
2. if pregnant, non-adherent, or unlikely to follow up desensitize and use Bicillin LA
123
What is the preferred treatment for syphilis acquired >1 year?
1. Bicillin LA 2.4 million units IM weekly X 3 weeks
2. beta-lactam allergy: Doxy x 28 days
124
What is preferred treatment of neurosyphilis (can happen at any stage of syphilis)?
Penicillin G aqueous IV; if allergy, desensitize
125
What is the preferred treatment of gonorrhea?
Ceftriaxone 500mg IM x 1 (<150kg) + Doxy if chlamydia has not been ruled out
Alternatives: cefixime, gentamicin, azythromicin
126
What is the preferred treatment of chlamydia?
Not pregnant: Doxy 100mg PO BID x 7 days
Pregnant: Azithromycin 1g PO x 1
127
What are the preferred treatments for bacterial vaginosis?
1. Metronidazole 500mg PO x 7 days
2. Metronidazole 0.75% gel intravaginally x 5 days
3. Clindamycin 2% cream intravaginally X 7 days (weakens latex condoms up to 72 hours after application)
128
What are the preferred treatments for trichomoniasis?
Female: Metronidazole 500mg PO BID x 7 days
Male: 2g PO x 1
Pregnancy: metronidazole CI during the 1st trimester per package labeling but the CDC recommends metronidazole for all trimesters
129
What is the preferred treatment of HPV gentile warts?
Imiquimod cream (Zyclara)
Prevention: Gardasil vaccine prevents genital wart and risk of cervical and other cancers
130
What are s/sx of the Rocky Mountain spotted fever?
1. erythematous petechial rash
2. death
131
What are treatments for Rocky Mountain Spotted Fever?
Doxycyline 100mg PO/IV BID x 5-7 days (including pediatric patients)
132
What are treatments for Lyme disease?
1. Doxy 100mg PO BID x 10d
2. amoxicillin 500mg PO TID x 14d
3. cefuroxime 500mg PO BID x 14 d
133
What are the treatments for ehrlichiosis?
Doxycyline 100mg PO/IV BID x 7-14 days
134
How is Lyme disease diagnosed?
enzyme immunoassay identifies antibodies; bulls eye rash
