Infectious Disease Flashcards

1
Q

Common SBI pathogens in Neonates (8)

A

GBS
Listeria monocytogenes
Salmonella
E. coli
Neisseria meningitides
S. pneumoniae
Haemaophilus influenzae type B
S. aureus

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

Empiric antibiotic coverage in neonates with a fever

A

Ampicillin + Gentamicin
or
Ampicillin + Cefotaxime
and
Acyclovir for HSV coverage

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

Fever in Neonate Pearls

A

Normal WBC does not exclude infection
If CSF pleocytosis, send CSF for HSV PCR
If RSV positive, risk for SBI does not change and full eval for SBI is indicated
An identifiable source is not found in most neonates with fever

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

Fever without a Source

A

Presence of fever when history and physical examination are unable to identify a specific etiology/cause in an acutely ill nontoxic-appearing infant/child <3 years of age

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

Common bacterial infection in older infants and children

A

S. aureus
Mycoplasma pneumoniae
N. meningitides
Salmonella

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

Empiric antibiotic coverage in young infants

A

Ampicillin, ceftriaxone, or cefotaxime and vancomycin

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

Empiric antibiotic coverage in older toxic-appearing infants and children

A

Ceftriaxone or cefotaxime and vancomycin

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

FWS Pearls

A
  • Approach to FWS is greatly impacted by infant/child’s immunization status
  • Fever >38.5 is not typically associated with teething
  • In older toddlers and children, incidence of occult bacteremia increases with height of temperature
  • Normal CBC and physical exam do not exclude meningitis
  • UTI is the most common cause of SBI in febrile infants
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

Fever of Unknown Origin

A

Fever >101F or 38.3C lasting for at least 8 days and up to 3 weeks with no apparent clinical diagnosis

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

Organism & Disease/System
Gram-positive cocci (aerobic)
- Staph. aureus
- Staph. epidermis
- Other staph species

A

Nosocomial: wound, ventilator
Neonatal
UTI
HAI

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

Organism & Disease/System
Gram-positive enterococcus (aerobic)
- Strep. gordoni
- Strep. pneumoniae
- Strep. mutans
- Strep. viridans

A

Endocarditis
Sepsis
Meningitis
UTI

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

Organism & Disease/System
Gram-positive cocci (anaerobic)
- Peptostreptococcus

A

Peritonitis; can occur anywhere (e.g., soft tissue, CNS, chest, bone)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

Organism & Disease/System
Gram-negative cocci
- N. meningiditis
- M. cattarhalis

A

Meningitis
Myocarditis
Otitis media
Sinusitis

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

Organism & Disease/System
Gram-positive bacilli
- L. monocytogenes
- C. difficile
- C. botulinum

A

Sepsis & Meningitis (L. monocytogenes); primarily <2mo of age
Antibiotic or hospital-acquired diarrhea (C. difficile)
Flaccid paralysis (C. botulinum)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

Organism & Disease/System
Gram-negative bacilli
- E. coli
- Enterobacter
- P. mirabilis
- K. pneumoniae

A

Wound infection
UTI
Meningitis
Bacteremia
Health care-associated infections

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

Fever and Neutropenia

A

Single temperature >38.3C or 38C for > 1 hour with an ANC <500 or an ANC that is expected to decrease <500 within in next 48hrs

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
17
Q

Health Care Associated Infections

A
  • HAI is an infection that is not present upon hospital admission but develops within 48 hours of admission in an acute care setting
  • Infections not present at discharge but apparent within 10 days after discharge are also considered to be of nosocomial origin
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
18
Q

Central Line-Associated Bloodstream Infections

A

A primary bloodstream infection in a patient who had a central line infection within 48-hour period before the development of BSI and the BSI is not related to another infected site

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
19
Q

Catheter-Associated UTI

A

A UTI in which an indwelling urinary catheter was in place for >2 calendar days when all elements of the CDC UTI infection criteria are present; the indwelling catheter must be in place on the day of, or the day prior to dx

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
20
Q

Nosocomial RSV

A

Symptoms of lower respiratory tract infection and RSV antigen >72 hours after hospital admission

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
21
Q

Surgical Site Infection

A

Infection occuring within 30 or 90 days after an operative procedure involving the skin, subcutaneous tissue, or deep soft tissues of the incision

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
22
Q

Three major groups of fungus

A
  • Yeasts: round/oval, unicellular, reproduce via budding; Ex. Candida
  • Molds: long, floppy, fluffy colonies that have long tubular structures called hyphae, reproduce via forming spore-forming structures called conidia; Ex. Aspergillus and Mucor
  • Dimorphs: change from yeast to mold and back, grow in environment as molds
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
23
Q

Clinical Presentation of Invasive Fungal Infections

A

In oncology patients, fever >4 days in neutropenic patient is suggestive of fungal infection
Purulent sinusitis/sinus pain is suggestive of Mucor infection
Persistent tachypnea and lower oxygen saturations suggest Pneumocystis jirovecci pneumonia (PJP)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
24
Q

Broad-spectrum coverage for invasive fungal infections

A
  • Micafungin
  • Amphotericin B
  • Azoles (often have multiple drug interactions)
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
25
Q

Treatment of confirmed PJP infection

A
  • IV trimethoprim-sulfamethoxazole (Bactrim)
    or
  • IV pentamidine for patient who cannot tolerate Bactrim
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
26
Q

Meningococcemia

A

Bacteremia and sepsis caused by the bacteria N. meningitidis, also referred to as meningococcus

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
27
Q

Multi-resistant Organisms

A
  • Methicillin-resistant Staph. aureus (MRSA)
  • Drug-resistant Strep. pneumoniae (DRSP)
  • Vancomycin-resistant enterococcus (VRE)
  • H. influenzae nontypable
  • Extended-spectrum B-lactamase (ESBL) producing E. coli and K. pneumoniae
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
28
Q

MRSA management

A

Vancomycin, clindamycin, Bactrim, linezolid

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
29
Q

DRSP management

A

Vancomycin, clindamycin, high-dose B-lactam, fluoroquinolones

30
Q

VRE management

A

Linezolid or daptomycin

31
Q

H. influenzae nontypable

A

Augmentin, extended-spectrum cephalosporins

32
Q

ESBL management

A

Broad-spectrum antibiotics, carbapenems

33
Q

Clinical Presentation of Meningococcemia

A
  • Initially: fever, malaise, vomiting, diarrhea, headache, myalgias
  • Later: limb pain, difficulty walking, maculopapular rash, signs of meningitis, including photophobia, nuchal rigidity, lethargy, and seizures
  • Fulminant: purpura, limb ischemia, shock, coma, death in as little as few hours
34
Q

Antibiotics used for Meningococcemia

A
  • IV ceftriaxone at meningitic doses (100mg/kg/day) for 5-7 days
  • Cefotaxime is also acceptable
  • May need to switch to penicillin G
  • Penicillin-allergic patients; use chloramphenicol or meropenem
35
Q

Prophylactic antibiotics w/in 24 hrs of close contacts of meningococcemia

A
  • Ciprofloxacin 500mg by mouth x1 dose
  • Ceftriaxone and rifampin are other options
36
Q

Antiviral therapy for Herpes Simplex Virus (HSV)

A
  • acyclovir
  • famciclovir
  • valacyclovir
37
Q

Antibiotic therapy for Gonorrhoeae

A

IM ceftriaxone + azithromycin or doxycycline

38
Q

Gonorrhoeae Pearls

A
  • major cause of cervicitis, pelvic inflammatory disease (PID), ectopic pregnancy, and infertility
39
Q

Chlamydia Pearls

A
  • Treatment: azithromycin or doxycycline
  • Leading cause of PID
40
Q

Syphilis antibiotic treatment

A

Benzathine penicillin G

41
Q

Systemic inflammatory response syndrome (SIRS) criteria

A

The presence of >2 of the following four criteria (one must be abnormal temperature or leukocyte count)
- hyperthermia or hypothermia
- tachycardia or bradycardia
- tachypnea
- leukocytosis or leukopenia

42
Q

Sepsis Pearls

A
  • Although not specific for bacterial infections, leukocytosis with a left shifted differential classically suggests a bacterial infectious etiology
  • Leukocytosis with a lymphocyte predominance is indicative of a viral infectious etiology
43
Q

Clinical Presentation of Epstein-Barr Virus

A
  • Fever, pharyngitis, malaise, lymphadenopathy, splenomegaly
  • Tonsillopharyngitis, cervical or peritonsillar abscess, meningitis, encephalitis, and may be associated with malignancy
44
Q

HSV Pearls

A
  • In HSV encephalitis, CSF analysis shows a lymphocytic pleocytosis, elevated protein level, and increased number of erythrocytes with an RBC count >1,000
  • MRI demonstrates temporal lobe enhancement
  • EEG may show paroxysmal lateral epileptiform discharges (PLEDs)
45
Q

Clinical Presentation of Parvovirus B19

A
  • Erythema infectiosum (fifth disease): intensely erythematous exanthem on cheeks with circumoral pallor (“slap cheek rash”), diffuse maculopapular rash that fades to a lacy erythematous rash, fever, headache, myalgias, malaise
46
Q

Diagnostic Evaluation

A
  • PCR, DNA hybridization, serologic antibody testing
  • CBC with diff, **reticulocyte count (will be decreased)
47
Q

Lemierre Syndrome Pathophysiology

A
  • Commonly caused by gram-negative anaerobic bacteria Fusobacterium necrophorum
  • Hematogenous spread of bacteria after passing through the oral mucosa either by direct tissue contact or via the tonsillar vessels
  • Results in septic thromboemboli in internal jugular vein
  • Microemboli circulate throughout the body developing abscesses and infarctations
  • Lungs are the primary site for septic emboli to lodge, followed by large joints such as hips, knees, and elbows
48
Q

Lemierre Syndrome Treatment

A
  • B-lactams, clindamycin, third-gen cephalosporins, vancomycin, metronidazole, and linezolid
  • Secure airway via intubation depending on degree of edema and risk of airway occlusion
  • Anticoagulation: controversial, initial treatment with heparin then to warfarin or enoxaparin for outpatient therapy
  • Surgical intervention: I&D or thrombectomy
49
Q

Pathogen causing Toxic Shock Syndrome

A

Staph. aureus and Strep. pyogenes (GAS)

50
Q

Clinical criteria for TSS

A
  • Fever > 102
  • Rash: diffuse macular erythroderma
  • Desquamation: 1-2 weeks following onset of rash
  • Hypotension: systolic BP <90mmHg for adults or less than 5th%ile for patients <16 years
  • Multisystem involvement (3 or more organ systems)
51
Q

Significance of Blood cultures in TSS

A
  • Blood cultures are positive for Staph. aureus in 10% of cases
  • Blood cultures are positive for GAS in >70% of cases
52
Q

TSS Management

A
  • Third gen cephalosporin and vancomycin for empiric therapy
  • Clindamycin should be added if suspicion for TSS is high
  • Consider IVIG
53
Q

Management of Lyme Disease

A
  • Doxycycline, amoxicillin, or cefuroxime
54
Q

Lyme Disease Pearl

A

Diagnosis is best made clinically in early stages of Lyme disease based on the presence of erythema migrans

55
Q

Clinical Presentation of Rocky Mountain spotted fever

A
  • Fever, headache, myalgias, abdominal pain, emesis, conjunctival injection, macular erythematous rash on wrists, ankles, palms, and soles which may spread to trunk
56
Q

Tick-borne illness caused by bacterium Rickettsia rickettsii

A

Rocky Mountain Spotted Fever

57
Q

Tick-borne illness caused by Borrelia burgdorferi

A

Lyme disease

58
Q

Tick-borne illness caused by Francisella tularensis

A

Tularemia

59
Q

Treatment for Tularemia

A

Streptomycin, gentamicin, or doxycycline

60
Q

Treatment for Rocky Mountain Spotted Fever

A

Doxycycline

61
Q

Clinical Presentation of Malaria

A
  • **Paroxysmal fever
  • Chills, headache, malaise, cough
62
Q

Diagnostic Evaluation of Dengue

A
  • Leukopenia with thrombocytopenia and elevated hematocrit should raise suspicion
  • Avoid agents likely to contribute to coagulopathy such as aspirin and NSAIDs
63
Q

Spastic muscle disorder caused by neurotoxin produced by Clostridium tetani found in contaminated wounds

A

Tetanus

64
Q

Management of Tetanus

A
  • Human tetanus immune globulin (TIG) 3,000-6,000 units IM
  • Antimicrobials: metronidazole or IV penicillin G
  • Vaccination
65
Q

Criteria to meet UTI in urine specimen

A
  • negative result: <10,000 bacteria/ml of urine
  • positive result: >100,000 bacteria/ml of urine; or >50,000 bacteria/ml urine in catheter specimen
66
Q

Neutrophils in CSF indicate what?

A

bacterial meningitis/cerebral abscess

67
Q

Mononuclear lymphocytes in CSF indicate what?

A

viral meningitis or encephalitis

68
Q

Contraindications to obtained CSF

A
  • increased ICP (can induce herniation)
  • patients who are receiving anticoagulation; risk of epidural hematoma
  • patients with infection near the lumbar puncture site
69
Q

Inflammatory marker that shows earlier and has a more intense rise (detectable 6-10hrs after inflammatory response)

A

C-reactive protein

70
Q

Normal range for CRP

A

<1.0mg/dL or <10mg/L

71
Q

Normal range for ESR

A

Male: up to 15mm/hr
Female: up to 20mm/hr
Child: up to 10mm/hr
Newborn: up to 0-2mm/hr

72
Q

CSF evaluation:
high WBC >1,000
low glucose
high protein

A

bacterial meningitis