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Royal College: Emergency Medicine > Infectious Disease > Flashcards

Infectious Disease Flashcards

This deck covers Chapters 121-130 in Rosens, compromising all of infectious disease.

1
Q

A 62 yo female had a tooth pulled 4 days ago. She now has severe neck pain with swelling. It feels woody on palpation.

Answer the following:

  • Diagnosis
  • Etiology
  • Symptoms
  • Treatment
A

Diagnosis

  • Ludwig’s angina

Etiology

  • Deep space infection
  • Submental, submandibular, sublingual spaces
  • Mixed flora (GAS, Bacteroides)
  • Typically from intra-oral/intra-pharyngeal sources

Symptoms

  • Swelling
  • Fever
  • Shortness of breath
  • Impaired neck mobility
  • Toxic appearing

Treatment

  • Pip-Tazo + Vancomycin + Clindamycin
  • ENT Consult in ED
  • Awake fiberoptic intubation, if necessary
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2
Q

You diagnose a 14-year-old female with pertussis. She lives at home with her parents and a 6-month-old brother.

Outline the stages of Pertussis and your management

A

Stages

  • Catarrhal (1-2 weeks) - infectious
  • Paroxysmal phase (1-2 months)
  • Convalescent phase

Management

  • Booster vaccine
  • Azithromycin (5 days)
  • Notify public health
  • Self-isolation for 3 weeks
  • All close contacts receive booster vaccine and Azithro
  • Household
  • Daycare
  • Child < 1-year-old
  • 3rd-trimester pregnancy
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3
Q

A 35-year-old male presents with a wound. Explain your approach to tetanus prophylaxis

A

If wound clean and:

  • Immunized <10 years ago = do nothing
  • Immunized >10 years ago = Td vaccine
  • Never immunized = Td vaccine

If wound dirty and:

  • Immunized <5 years ago = do nothing
  • Immunized >5 years ago = Td vaccine
  • Never immunized = Td vaccine + HTIG
  • HTIG dose = 250 U IM

Dirty Defined As:

  • > 6 hours old
  • > 1 cm deep
  • Contaminated (dirt, feces, soil, saliva)
  • Puncture
  • Stellate
  • Avulsions
  • Denervated
  • Ischemic
  • Infected
  • Missiles
  • Crush
  • Burns
  • Frostbite
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4
Q

A kid comes in walking with a limp. Severe decreased ROM of the hip. He is febrile. You suspect a septic hip.

What criteria can be used to diagnose this?

A

Kocher Criteria

NEWF

  • NWB on the affected side
  • ESR > 40
  • WBC > 12
  • Fever (T >38.5)
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5
Q

Describe the signs and symptoms of Ebola. How long after a possible exposure should you be worried?

A

Ebola Virus

Transmission

  • Human-to-Human
  • Direct contact with blood + bodily fluids

Incubation Period

  • Up to 3 weeks

Who to suspect it in

  • Travel to an endemic country
  • Contact with confirmed Ebola patient and symptomatic

Symptoms

  • Sudden onset fever, malaise, myalgia, severe H/A
  • Conjunctivitis, pharyngitis, N/V/D
  • Hepatic + renal impairment
  • Maculopapular or petechial rash
  • Mucosal bleeding (50%)
  • Multiorgan failure, shock, and death
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6
Q

Describe the epidemiology, pathophysiology, and clinical features of Staphylococcal Scalded Skin Syndrome (SSSS)

A

Epidemiology

  • Children (6 months – 6 years)
  • Mortality = 3%
  • Adults
  • Mortality = 50%

Pathophysiology

  • Toxin-producing S. aureus
  • Epidermolytic toxin A or B
  • Acts on Desmoglein 1 protein (Dsg1)
  • Results in the separation of the skin

Clinical Presentation

  • Positive Nikolsky’s sign
  • Erythema
  • Blisters, bullae, and vesicles
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7
Q

List FIVE DDx for tetanus

A
  1. Strychnine Poisoning
  2. Dystonic Reaction
  3. Hypocalcemia
  4. Status Epilepticus
  5. Rabies
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8
Q

What is the most common cause of focal intracranial mass lesions in HIV infection?

A

Toxoplasmosis

  • Parasitic disease
  • Poorly cooked food w cysts or cat feces exposure
  • ½ of people are infected by toxo but have no symptoms

Clinical

  • Headache
  • Fever
  • Altered mental status
  • Seizures, focal deficits

CT (with contrast) Features

  • Ring enhancing lesions
  • Multiple lesions
  • Basal ganglia and corticomedullary area

Treatment

  • Pyrimethamine 100-200mg PO then 50-100 mg/day
  • Sulfadiazine 4-8 g/day PO
  • Folinic acid 1 mg/day PO (prevents pancytopenia)
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9
Q

List FOUR clinical and FOUR lab findings that are criteria for severe malaria and poor prognosis

A

Clinical

  • GCS <11
  • Weakness
  • Seizures (>2/day)
  • Pulmonary edema (Hypoxia + RR >30)
  • Bleeding
  • Shock

Lab

  • Hypoglycemia (<2.2 mmol/L)
  • Acidosis (Base Deficit >8, Bicarb <15, Lactate >5)
  • Anemia (HgB <70 adults, <50 children under 12, HCT <15%)
  • Renal impairment (Cr >265, BUN >20)
  • Bilirubin >50
  • Parasite count >10% (for P. falciparum)
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10
Q

What is the causative agent in RMSF? How does it cause disease? What is the vector?

A

Rickettsia rickettsii

  • Obligate intracellular bacteria
  • Invades vascular endothelium causing vasculitis

Vector

  • Rocky Mountain wood tick (Dermacentor andersoni)
  • Dog tick (Dermacentor variabilis)
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11
Q

List the culprit organisms and treatment regimens for septic arthritis if the Gram’s stain shows:

  • Gram + cocci
  • Gram – cocci (sexually active patient)
  • Gram – bacilli
  • Gram + bacilli
A

Gram + cocci

  • S. aureus

Gram – cocci (sexually active patient)

  • N. gonorrhea

Gram – bacilli

  • E. coli, P. aeuriginosa

Gram + bacilli

  • P. acnes
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12
Q

List SIX rashes that can affect hands/soles of feet

A
  1. Secondary syphilis
  2. RMSF
  3. Coxsackie (HFM)
  4. Smallpox
  5. Kawasaki
  6. Meningococcemia
  7. Endocarditis
  8. DIC
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13
Q

What are the TWO pneumococcal vaccines available in Canada? When are they indicated?

A

PREVNAR-13

  • Pneumococcal 13-valent conjugate vaccine
  • Used to prevent IPD (invasive pneumococcal disease)
  • Indications:
  • All infants at 2 mo, 4 mo, 12 mo

PNEUMOVAX-23

  • Pneumococcal 23-valent polysaccharide vaccine
  • Indications
  • All adults ≥ 65 years
  • ‘Other’: homeless, alcoholic, smoker, drug user
  • Immunocompetent adults + high risk for IPD
  • Immunocompromised adults + high risk for IPD
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14
Q

List potential regimens for drug-resistant TB

A

Usually ‘RIPE’, replace I with a fluoroquinolone.

  • Rifamipin
  • Pyrazinamide
  • Ethambutol
  • Fluoroquinolone
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15
Q

List FOUR features of osteomyelitis on plain XR

A
  1. Involcrum (Periosteal reaction)
  2. Lucent areas
  3. Lytic lesions surrounded by dense sclerotic bone
  4. Sequestra
  5. Deep soft tissue swelling & fascial plane separation
  6. Altered fat interfaces
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16
Q

Provide a differential diagnosis for respiratory infections in HIV+ patients based on CD4 count

A

CD4 >200

  • Regular pneumonia

CD4 <200

  • PCP, Histo, Cryptococcus, TB

CD4 <50

  • PCP, MAC, CMV, and everything above
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17
Q

What is the typical presentation of septic arthritis (clinical or lab)?

A

Symptoms

  • Fever
  • Joint pain
  • Malaise

Lab Tests (C’s)

  • Cell count (WBC >50 cutoff)
  • Crystals
  • Chemistry (Lactate, glucose, protein)
  • Culture
  • Gram stain
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18
Q

What are 5 complications of pertussis? How is it diagnosed?

A

Diagnosis

  • NP swab + PCR (3-7 days for results)

Complications

  1. Respiratory failure
  2. Hernias
  3. Hemoptysis
  4. Pneumothorax
  5. Subcutaneous emphysema
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19
Q

Your patient has a parasitemia of 15% and it’s falciparum. Outline your management.

A

Severe Malaria Treatment (AM QD)

  • Option A (‘AM’): Artesunate + Malarone IV
  • Preferred
  • Option B (‘QD’): Quinidine + Doxycycline IV
  • Admit to ICU
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20
Q

How would you treat meningococcemia? Are steroids indicated for bacterial meningitis?

A

Treatment

  1. Ceftriaxone 2g IV q12h
  2. Vancomycin 15 mg/kg q12h
  3. Dexamethasone 8 mg IV
    * Decreased mortality in S. pneumoniae
    * Decreased hearing loss in H. influenzae
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21
Q

Outline your management of a patient with tetanus

A

Supportive Care

  • Muscle spasms
  • Benzodiazepines (*diazepam is the best-studied)
  • Dantrolene (adjunct)
  • MgSO4 (improved spasm control)
  • Airway Protection (if above fails)
  • Avoid sux
  • Autonomic instability
  • Labetalol or propranolol

Elimination of Tetanospasmin (TS) & Active Immunization

  • HTIG 250 IU IM
  • Neutralizes any circulating toxin
  • Neutralizes toxin at the site of production
  • Reduces mortality
  • Td 0.5 mL IM
  • Give at a separate site

Prevention of further toxin production

  • Wound debridement
  • Metronidazole 500 mg IV/PO Q6H (drug of choice)
  • Avoid PCN which inhibits GABA and synergizes with TS
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22
Q

Discuss Rabies post-exposure prophylaxis

A

Wound Care

  • Scrub with soap/water

Tetanus prophylaxis

  • Td 0.5 mL IM (if not vaccinated)

Human Rabies IG (HRIG)

  • HRIG 20 IU/kg
  • Infiltrate full dose into and around the wound
  • Remainder is given IM

Human Diploid Cell Vaccine (HDCV)

  • If never vaccinated:
  • Days 0, 3, 7, 14, 28 (5 doses)
  • If previously vaccinated:
  • Days 0 and 3 (2 doses)
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23
Q

Chikungunya. Describe its vector, duration of illness, and complications.

A

Vector

  • Aedes mosquitoes

Symptoms

  • Fever - usually ends abruptly after 2 days
  • Arthralgia/Arthritis - significant
  • Headache
  • Insomnia
  • Rash

Diagnosis

  • Serology, RT-PCR

Treatment

  • NSAIDs

Complications

  • Myocarditis
  • Hepatitis
  • Nephritis
  • Meningitis
  • Guillain-Barré syndrome
  • Cranial nerve palsies
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24
Q

What is the causative agent in Diphtheria? Explain the pathophysiology, types of disease, and management.

A

Etiology

  • Corynebacterium Diptherae

Types

  • Respiratory Diphtheria
  • Greatest toxicity
  • Pharyngeal, Nasal, Laryngeal
  • Cutaneous Diphtheria
  • Least toxic

Pathophysiology

  • Produces exotoxin that inhibits cellular protein synthesis
  • Affects: Nervous System + Heart + Kidneys

Treatment

  • Erythromycin 50 mg/kg/day
  • Diphtheria antitoxin
  • Vaccinate
  • Self-isolation
  • Notify Public Health
  • Vaccinate close contacts
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25
Q

Which ONE parasite is well known to cause cardiomyopathy?

A

Chagas Disease

Parasite

  • Trypanosoma cruzi

Symptoms

  • Acute (1 – 2 months)
  • Fever
  • Facial and dependent extremity edema
  • HSM, LAD
  • Peripheral smear: lymphocytosis
  • Elevated LFTs
  • Chronic (25% of patients)
  • Cardiac
    * Invasion of muscle + fibrosis/inflammation
    * Bradycardia, BBBs, Heart blocks, VT/VF
  • GI symptoms

Treatment

  • Nifurtimox 2 mg/kg PO QID x4 months
  • Alternative: Benznidazole
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26
Q

Describe the clinical presentation and treatment of cryptococcal infection in HIV infected patients.

A

Clinical Presentation

  • Fever
  • Headache
  • Visual disturbance
  • Seizures
  • Usually CD4 < 100
  • Causes focal or diffuse meningoencephalitis

Treatment

  • 3 phases: induction, consolidation, maintenance
  • If abnormal mental status
  • Amphotericin B 0.7 mg/kg/day IV
  • +/- 5-Flucytosine
  • If normal mental status
  • Fluconazole 400 mg/day PO
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27
Q

List guidelines for the management after accidental exposure to TB at work? What FOUR populations get PEP?

A

If exposed at work

  • Get a TB skin test early for baseline
  • Re-test in 3 months to see if there is the conversion

PEP INH

  1. Significant exposure in PPD Negative person
  2. PPD Negative who converts after exposure
  3. PPD Positive and no pre-exposure PPD available
  4. Immunocompromised <35 yo
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28
Q

Outline the WHO pandemic phases

A

Phase 1

  • Infection in animals only

Phase 2

  • Isolated animal-to-human transmission

Phase 3

  • Sporadic human-to-human transmission
  • Not enough for community outbreak

Phase 4

  • Human-to-human transmission
  • Able to sustain community-level outbreaks

Phase 5

  • Human-to-human transmission
  • Spread to 2+ countries in one WHO region

Phase 6

  • Human-to-human transmission
  • Spread to at least two WHO regions
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29
Q

Outline the stages of HIV infection as per the CDC surveillance case definitions

A

Stage 1

  • CD4 >500
  • No AIDS-defining illness

Stage 2

  • CD4 200-499
  • No AIDS-defining illness

Stage 3

  • CD4 <200
  • Any AIDS-defining illness present
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30
Q

List SIX complications of severe P. falciparum malaria

A
  1. Cerebral malaria
    * Cerebral edema + encephalopathy
  2. Metabolic acidosis
  3. Severe anemia
  4. Pulmonary edema
  5. Hypoglycemia
  6. AKI
  7. DIC
  8. Death
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31
Q

Name 4 complications of measles.

A
  1. Sub-acute sclerosing panencephalitis (SSPE)
  2. Laryngitis
  3. Tracheobronchitis
  4. Pneumonitis
  5. Secondary bacterial pneumonia
  6. Encephalomyelitis
  7. Vitamin A deficiency & blindness
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32
Q

List signs & symptoms of RMSF

A

Constitutional

  • Fever, malaise

Neurologic

  • H/A, meningismus, cerebral vasculitis
  • Ataxia

Cardiac

  • LV dysfunction
  • Arrhythmias (1st deg AVB, A fib)
  • Cardiac enlargement on CXR
  • ECG: nonspecific ST-T changes

Pulmonary

  • Interstitial pneumonitis

MSK

  • Severe myalgias

Hematologic

  • DIC (fulminant cases)

Dermatologic

  • Rash
  • Initially:
    * 1 – 5 mm pink to red macules
    * Blanches
    * Begins on ankles & wrists
    * Palms + Soles (50%)
    * Spreads centripetally to forearms, legs, thigh, trunk +/- face
    * Enhanced by warm compresses
    * Not palpable
  • 2 – 3 days
    * Becomes maculopapular
    * Deepens in redness
    * Palpable
    * No longer blanches

Rumpel-Leede phenomenon

  • Rash enhanced by tourniquet or BP cuff
  • Distal shower of petechiae that occurs immediately after release of a tourniquet or BP cuff
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33
Q

List 10 conditions that require droplet precaution

A
  1. Adenovirus, respiratory strains
  2. Bocavirus
  3. Coronavirus
  4. Diphtheria, pharyngeal
  5. H. influenzae, in children
  6. Human metapneumovirus
  7. Influenza, seasonal, avian
  8. Meningococcus
  9. Monkeypox
  10. Mumps
  11. Mycoplasma pneumoniae
  12. Parainfluenza virus
  13. Parvovirus B-19
  14. Pertussis
  15. Plague, pneumonic
  16. RSV
  17. Rhinovirus
  18. Rubella
  19. SARS
  20. Smallpox
  21. Streptococcus, Group A
  22. Scarlet fever
  23. Viral hemorrhagic fevers
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34
Q

List EIGHT DDx for botulism

A
  1. GBS
  2. Tick paralysis
  3. Myasthenia gravis
  4. Lambert-Eaton syndrome
  5. Diphtheria
  6. Brainstem CVA
  7. Anticholinergics
  8. Organophosphates
  9. Dystonic reactions
  10. Heavy-metal poisoning
  11. Mg toxicity
  12. Paralytic shellfish poisoning
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35
Q

List 8 risk factors for necrotizing fasciitis (NF)

A
  1. DM
  2. Vascular insufficiency
  3. Immunosuppression
  4. Penetrating trauma
  5. Post-surgical
  6. Varicella infection (+NSAIDs!!)
  7. IVDU
  8. Burns
  9. Childbirth
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36
Q

Staphylococcal scalded skin syndrome vs. TEN

A

Staph Scalded Skin Syndrome

    • Nikolski
  • Oral mucosal sparing
  • Unwell, but not shocky
  • No history of drug exposure
  • Responds to antibiotics

Toxic Epidermal Necrolysis

    • Nikolski at the lesion
  • Full-thickness of skin
  • Oral mucosal regions involved
  • Very unwell
  • Drug exposure
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37
Q

List 5 host and 5 environmental risk factors for tuberculosis

A

Environmental Factors

  1. Close contacts
  2. Health care workers
  3. Birth in TB endemic area
  4. Overcrowding/poor ventilation
  5. Low SES
  6. Homeless
  7. Longterm care facilities
  8. Prisons

Host Factors

  1. HIV+
  2. Elderly
  3. IVDU
  4. Steroid use, immunosuppressive tx
  5. DM2
  6. Hematologic malignancy
  7. Malnourished
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38
Q

What are the characteristics of neonatal & infant bone infections? How does this differ compared to children aged 1 – 17 years & adults?

A

Neonates/Infants

  • Spreads from metaphysis to the epiphysis
  • Vessels cross growth plate
  • No pressure-related necrosis
  • Cortex allows the release of pressure
  • Develop abscesses; Involucrum formation

Children Age 1 – 17 Years

  • No spread to the epiphysis
  • Epiphyseal plate = avascular
  • No pressure-related necrosis
  • Cortex still allows the release of pressure
  • Subperiosteal abscess formation

Adults

  • Spread from metaphysis to epiphysis again
  • Due to anastomosis of vessels across the plate
  • Pressure-related necrosis
  • No abscess formation
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39
Q

List EIGHT tick-borne illnesses (disease & pathogen)

A
  1. Lyme - Borrelia burgdorferi
  2. Tularemia - Francisella tularensis
  3. RMSF - Rickettsia rickettsii
  4. Q fever - Coxiella burnetii
  5. Human monocytic ehrlichiosis - Ehrlichia chaffeensis
  6. Human granulocytic anaplasmosis - Anaplasma phagocytophilum
  7. Babesiosis - Babesia microti
  8. Colorado tick fever - Orbivirus
  9. Tick paralysis - Ixobotoxin
40
Q

In a confirmed case of meningococcemia, what is the prophylaxis and who should get it?

A

Indications

  • Household contacts, daycare/nursery contacts
  • HCWs with intimate exposure (intubation, suctioning etc.)

Prophylaxis

  • Ciprofloxacin 500 mg PO x1
  • Adults only
  • Rifampin 10 mg/kg (max 600 mg) Q12H x4 doses
  • Warn patients that secretions will be orange
  • Ceftriaxone 250 mg IM
  • If <12 years old: 125 mg IM
  • Use in pregnancy
41
Q

Discuss MERS-CoV transmission and symptoms.

A

MERS-CoV (Coronavirus)

Transmission

  • Human-to-human (typically in healthcare settings)

Suspect In

  • Travel to Middle East + respiratory symptoms
  • Being in a healthcare facility or contact with camels

Symptoms

  • Fever, cough, SOB
  • Pneumonia is common
  • +/- N/V/D
  • Can get severe pneumonia, ARDS, sepsis
42
Q

Use Waldvogel’s system to classify osteomyelitis

A
  • Hematogenous
  • Contiguous
  • Person with Vascular Insuffiency
43
Q

List and describe the FOUR forms of tetanus

A

Generalized Tetanus

  • Spasms throughout the body
  • Trismus (lockjaw; masseter spasm)
  • Sardonic smile (risus sardonicus; facial muscles)
  • Opisthotonos (looks like decorticate posturing)

Localized Tetanus

  • Persistent muscle spasms close to site of injury
  • May progress to generalized tetanus

Cephalic Tetanus

  • CN palsies + muscle spasms
  • Most common = CN VII (mimics Bell’s palsy)
  • Rare variant of localized tetanus
  • 1/3 recover, 2/3 develop generalized tetanus

Neonatal Tetanus

  • Irritability + poor feeding (1st week of life)
44
Q

Describe the stages of Lyme disease. How do you diagnose?

A

Lyme Disease

Stages

  • Early
  • ​Erythema migrans
  • Disseminated
  • ​Carditis
  • Neuro (meningitis, CN palsy)
  • Arthritis
  • Late Lyme
  • ​Arthritis
  • Fatigue
  • Neurocognitive deficits

Diagnosis

  • Clinical (erythema migrans + history)
  • Serology (two-tier strategy):
  • Step 1: ELISA (if negative, stop)
  • Step 2: Western blot (confirmatory)
  • Must interpret serology within clinical context:
  • IgM (peaks 3 – 6 weeks)
  • IgG (seen at > 2 months; peaks 12 months)
  • IgM alone at > 4 weeks is a false positive
  • IgG may persist for years
45
Q

What are the THREE distinct clinical stages of pertussis?

A

Catarrhal

  • 1-2 weeks
  • Infective
  • URTI symptoms

Paroxysmal

  • 1-2 weeks
  • Not infective
  • Coughing and whoop

Convalescent

  • Coughing for 90 days
46
Q

Cellulitis vs. Necrotizing Fasciitis vs. Myonecrosis

A

Cellulitis

  • Superficial
  • Predisposing trauma
  • May need I+D
  • Staph/Strep

Necrotizing

  • Deep soft tissue infection
  • Trauma, surgery, DM
  • Needs surgical debridement + ABx
  • Mixed anaerobic

Myonecrosis

  • Through fascia into muscular layers
  • Trauma, contaminated wounds
  • Clostridia, anaerobes
47
Q

What is an involucrum? What are sequestra?

A

Involuvrum

  • Formation of new periosteum in osteomyelitis
  • “Periosteal reaction”

Sequestra

  • Ischemic bone separates from the rest of the bone
  • Seen in advanced or chronic osteomyelitis
48
Q

How do you differentiate periorbital vs. orbital cellulitis?

A

Periorbital Cellulitis

  • Pre-septal (eyelid and surrounding tissues)
  • No decreased VA
  • No pain with EOM
  • No proptosis
  • Unilat erythema, swelling, warmth, tenderness of eyelid
  • S. aureus, GAS
  • Amox-Clav/Clindamycin
  • Outpatient ophthalmology

Orbital Cellulitis

  • Past the orbital septum
  • Decreased VA
  • Pain with EOM
  • Proptosis
  • Blurred vision, ophthalmoplegia, proptosis, and chemosis
  • Toxic
  • S. aureus, GAS, pneumococcus
  • Ceftriaxone + Vancomycin IV
  • add Flagyl if concerned re: CVST
  • Inpatient ophthalmology
49
Q

What is the incubation period for malaria? Dengue?

A

Dengue = <10 days

Malaria = 11-21 days

50
Q

Outline the doffing order for PPE

A
  1. Gloves
  2. Gown
  3. Hand hygeine
  4. Eye shield
  5. Mask
  6. Hand hygeine
51
Q

Give 8 examples of persons at risk who should be tested for latent TB infection

A
  1. Recent close contact
  2. HCWs around active TB
  3. Foreign-born from endemic areas
  4. Homeless
  5. Living/working in LTC facilities
  6. HIV
  7. Recent TB infection
  8. IVDU
  9. ESRD
  10. DM
  11. Immunosuppressants
  12. Hematologic cancers
  13. Malnourished
  14. Recent weight loss >10%
  15. Gastrectomy/jejunoileal bypass
52
Q

List SIX risk factors for developing active TB in a previously infected individual

A
  1. HIV
  2. IVDU
  3. Cancer (especially head and neck)
  4. ESRD
  5. DM
  6. Abnormal CXR
  7. TB in the last 2 years
53
Q

What is the treatment for PCP pneumonia?

A

PCP Pneumonia

  • Immunocompromised patients, HIV CD4 <200
  • Pneumocystis jiroveci
  • Gradual (3 weeks)
  • Resp symptoms, cough, fever, progressive SOB
  • Elevated LDH
  • CXR = diffuse, bilateral, interstitial, or alveolar infiltrates
  • Get HIV screen

Treatment

  • Septra 20 mg/kg/day div TID
  • 2 Septra DS tabs PO q 8hrs
  • Steroids if:
  • A-a O2 gradient ≥35 mmHg
  • PaO2 <70 mmHg
  • Respiratory failure
54
Q

List SEVEN AIDS-defining illnesses

A
  1. Kaposi sarcoma
  2. Oral candidiasis
  3. CMV retinitis
  4. CMV colitis
  5. PCP pneumonia
  6. MAC
  7. CNS Lymphoma
  8. Toxoplasmosis
  9. Disseminated fungal infections
55
Q

Give a differential for “cavitary” lung disease

A

CAVITY

  • Cancer – bronchogenic, mets
  • Autoimmune/granulomatous – Wegener’s, RA
  • Vascular – septic/non-septic emboli
  • Infectious – TB, MRSA/MSSA, Klebsiella, Coccidiomycosis, cryptococcus, blasto
  • Trauma – pneumatocele
  • Youth – CPAM, bronchogenic cyst
56
Q

Identify the disorders caused by HHV strains

A
  • HSV 1: Herpes labis
  • HSV 2: Genital herpes
  • HSV 3: VZV (chicken pox)
  • HSV 4: EBV (Mononucleosis)
  • HSV 5: CMV
  • HSV 6: Roseola (6th Disease)
  • HSV 7: Not a thing
  • HSV 8: Kaposi Sarcoma
57
Q

List 6 possible causes of ring-enhancing lesions on CT head.

A
  1. Cerebral abscess
  2. Tuberculoma
  3. Neurocysticercosis
  4. Toxoplasmosis
  5. CNS Lymphoma
  6. Fungal granulomas
  7. Metastatic cancer
  8. Glioblastoma
  9. Sarcoidosis
  10. Subacute infarct/hemorrhage/contusion
  11. Demyelination (incomplete ring)
  12. Radiation necrosis
  13. Postoperative change
58
Q

List 8 ABX with activity against MRSA

A

PO

  1. TMP/SMX
  2. Clindamycin
  3. Doxycycline
  4. Linezolid
  5. Rifampin (IDSA says no)

IV

  1. Daptomycin
  2. Linezolid
  3. Vancomycin
  4. Dalbavancin
  5. Oritavancin
59
Q

A 42-year-old homeless male presents with muscular rigidity and a clenched jaw. He is tachycardic and mildly hypertensive. You notice that he has needle track marks and a sardonic smile.

Give a detailed explanation of why this patient is having muscle spasms.

A

Wound Tetanus

Etiology

  • Clostridium tetanii

Pathophysiology

  • Neurotoxin produced called tetanospasmin (TS)
  • Binds motor nerve endings & moves to the CNS
  • Binds inhibitory neurons and blocks release of inhibitory neurotransmitters (GABA + glycinergic)
  • Motor neurons undergo sustained excitatory discharge
  • This causes muscle spasms
60
Q

How is Zika transmitted? What are the symptoms? What is the concerning complication?

A

Zika Virus

  • Arbovirus (arthropod-borne virus)

Transmission

  • Transmitted by a mosquito - Aedes
  • Direct human-human spread – sexually
  • Perinatal transmission recently reported

Symptoms

  • Rash
  • Conjunctivitis
  • Arthralgias
  • 80% asymptomatic
  • Associated with microcephaly
61
Q

Compare and contrast Cellulitis vs. erysipelas

A

Cellulitis

  • Extends into SC tissue
  • Blanching erythema
  • Flat
  • Poorly demarcated
  • S. aureus/Strep
  • Keflex/Ancef

Erysipelas

  • Superficial
  • Indurated
  • Raised
  • Sharply demarcated
  • S. pyogenes (GAS)
  • PCN G
62
Q

Compare and contrast:

  • Staphylococcal Scalded Skin Syndrome (SSSS)
  • Staphylococcal TSS
  • Streptococcal TSS
A

SSSS

  • 6 months to 6 years typically
  • Niksolski +
  • Mucosal sparing
  • Not shocky, kids look miserable but not dying
  • Epidermolytic Toxin A and B

Staph TSS

  • Probable case = 4 clinical + lab
  • Confirmed case = 5 clinical + lab
  • Clinical Criteria
  • Fever
  • Rash
  • Desquamation
  • Hypotension
  • 3+ of:
    * GI (Vomiting/Diarrhea)
    * MSK (Myalgia or CK >2x ULN)
    * Mucous membrane hyperemia
    * Renal (BUN or Cr >2x ULN)
    * Hepatic (LFTs/Bili >2x ULN)
    * Platelets <100
    * Altered LOC
  • Laboratory Criteria
  • Cultures negative for alternative pathogens
  • Serology negative for RMSF, leptospirosis, measles
  • Usually from a wound or a foreign body
  • TSST-1 toxin

Streptococcal TSS

  • Probable case = Clinical + GAS from non-sterile site
  • Confirmed case = Clinical + GAS from sterile site
  • Clinical Criteria
  • Hypotension
  • 2+ of:
    * Renal impairment (Cr >177)
    * Coagulopathy (Platelets ≤100 or DIC)
    * Liver (LFTs or Bili >2x ULN)
    * ARDS
    * Erythematous macular rash
    * Soft tissue necrosis
  • Laboratory Criteria
  • Isolation of GAS
  • Usually more painful
  • Exotoxin A and B
63
Q

List 6 of the most common animal reservoirs for rabies transmission to humans

A
  1. Bat
  2. Raccoon
  3. Skunk
  4. Fox
  5. Dog
  6. Cats
  7. Coyotes
  8. Wolves
  9. Some cases of cattle and horses
64
Q

A patient being treated with doxy for Lyme feels like hot garbage the next day: is this normal?

A

Jarisch-Herxheimer Reaction

  • Reaction occurs 24 hours after ABx against spirochetes
  • Dying bacteria release pyrogens

Symptoms

  • Malaise, chills, myalgias, headache
  • Fever, tachycardia, tachypnea, hypotension
  • Mild leukocytosis
65
Q

List the 4 clinical stages of rabies

A

Incubation

  • Duration dependent on proximity to CNS
  • Closer to the brain is shorter

Prodrome

  • Headache, runny nose, sore throat, myalgias, GI symptoms, back pain, muscle spasms, agitation, anxiety
  • Paresthesias, pain, or severe itching at the bite

Acute Neurologic Illness – 2 forms

  • Furious (Encephalopathic) – 80%
  • Agitation, hydrophobia (can’t swallow), extreme irritability, hyperexcitability with periods of lucidity, tachycardia, tachypnea, fever, hallucinations, seizures, ataxia, weakness, arrhythmias
  • Dumb (Paralytic) – 20%
  • Prominent limb weakness, fever, no hydrophobia

Coma

66
Q

At what point should HIV infected patients be started on prophylaxis for specific opportunistic infections?

A

CD4 <200

  • Septra for PCP

CD4 <100

  • Septra for Toxo

CD4 <50

  • Azithromycin for MAC
67
Q

Describe measles (Rubeola) re: etiology, incubation period, symptoms, management & FOUR complications

A

Spread

  • Airborne respiratory droplets

Incubation

  • 10 – 14 days

Symptoms

  • Cough, coryza, conjunctivitis, fever
  • Koplik spots (pathognomonic)
  • Rash:
  • Starts on head/face to trunk to extremities
  • Macular or maculopapular
  • Becomes confluent as it progresses

ED Management

  • Airborne precautions
  • Supportive care
  • Notify public health

Complications

  1. Diarrhea
  2. AOM
  3. Pneumonia
  4. Encephalitis
  5. Optic neuritis
  6. Stillbirth
68
Q

List common classes of HIV medication

A
  • Nucleoside reverse transcriptase inhibitors (NRTIs)
  • Non-nucleoside reverse transcriptase inhibitors (NNRTIs)
  • Protease inhibitors (PIs)
  • Integrase strand transfer inhibitors (INSTIs)
69
Q

List one organism that can cause SSTI from wound exposure to SEAWATER and one from FRESH WATER.

A

Seawater

  • Vibrio (Doxycycline)

Freshwater

  • Aeromonas (Ciprofloxacin)
70
Q

What is Nikolsky’s Sign?

A

Easy separation of the outer portion of the epidermis from the basal layer when pressure is applied

DDx

  • SSSS
  • TEN/SJS
  • Pemphigus Vulgaris
  • Bullous Pemphigoid
71
Q

Outline your management for (a) an adult patient with botulism and (b) infant botulism

A

Management of Adult Botulism - Food Borne

  • Equine trivalent antitoxin 10 mL vial
  • Neutralizes only circulating toxin
  • No effect on bound toxin
  • Saline enemas & cathartics
  • To cleanse GI tract
  • Ensure you avoid Mg-containing cathartics (hyperMg can worsen muscle weakness)

Management of Adult Botulism - Wound

  • Equine trivalent antitoxin 10 mL vial
  • Neutralizes only circulating toxin
  • No effect on bound toxin
  • Antibiotics
  • PCN
  • Wound care
  • Soap, water, tetanus

Management of Adult Botulism - Iatrogenic

  • Equine trivalent antitoxin 10 mL vial
  • Neutralizes only circulating toxin
  • No effect on bound toxin

Management of Infantile Botulism

  • BabyBIG
  • Pooled plasma from immunized adults with high titers of antibodies to toxins A+B

Airway

  • FVC <20 mL/kg = intubate
  • MIP <30 cmH2O = intubate
  • MEP <40 cm H2O = intubate
72
Q

List SIX parasites that cause fever

A
  1. Plasmodium species (Malaria)
  2. Borellia species (Lyme)
  3. Schistosomiasis
  4. African trypanosomiasis
  5. Trypanosoma cruzi (Chagas)
  6. Leishmaniasis
  7. Toxoplasma gondii (Toxoplasmosis)
  8. Entamoeba histolytica (Amoebic liver abscess)
73
Q

List 5 conditions that must be placed on airborne precautions

A
  1. Measles
  2. Monkeypox
  3. Tuberculosis (Pleuropulmonary or laryngeal)
  4. Smallpox
  5. Varicella-zoster virus
    * Varicella (chickenpox)
    * Zoster, disseminated
    * Zoster, in an immunocompromised patient
  6. COVID-19/SARS/Ebola during aerosolizing procedures
74
Q

What are some features of Dengue?

​

A

Transmission

  • Aedes mosquito

Incubation

  • <12 days

Symptoms​

  • Severe flu-like illness
  • Fever
  • Headache
  • N/V/D, Abdo pain
  • Myalgias, Arthralgias
  • Rash

Phases

  1. Febrile
  2. Critical
    * Plasma leak, low PLT, low WBC, severe dehydration
    * <5% will develop hemorrhage or shock
  3. Recovery/Convalescence
75
Q

A vet student is going to an area endemic with rabies. How would you prep her?

A

HDCV 1 mL IM (Deltoid)

  • Days 0, 7, and 21 or 28 (3 doses)
76
Q

Describe the symptoms of food-borne botulism

A

Person eats canned food with preformed toxin

Symptoms (18 – 36 h later)

  • Early
  • Weakness, malaise, light-headed, n/v, constipation
  • Neurologic
  • CNS affected first
  • Diplopia, blurred vision, dysphonia, dysphagia, dysarthria
  • Vertigo (common)
  • Ocular signs
  • Ptosis
  • EOM palsies
  • Dilated + fixed pupils
  • Weakness
  • Symmetrical, descending
  • UE > LE; proximal > distal
  • Classic: neck muscles often weak
  • DTRs have variable findings (normal, depressed or absent)
  • Sensory exam is NORMAL
  • ANS parasympathetic blockade
  • Decreased salivation; ileus; urinary retention
77
Q

What are FIVE risk factors for TSS?

A
  1. Tampons
  2. Nasal packing
  3. EtOH abuse
  4. Immunocompromise
  5. DM
  6. COPD
78
Q

How is malaria diagnosed?

A

Thick & Thin Smears

  • Smears q12h until 3 sets negative

Thick smear

  • Maintains the integrity + morphology of RBCs so that parasites are visible within RBCs (SCREENING)
  • Estimates parasite density

Thin smear

  • Allows identification of malaria species
  • Measures parasite density
79
Q

Outline your management of TSS (Strep and Staph)

A
  1. IV O2 Monitors
  2. Blood cultures
  3. Fluids MAP >65
  4. Pressors
  5. Antibiotics
    * Pip-Tazo 4.5g IV q6h
    * Vancomycin 15 mg/kg IV q12h
    * Clindamycin 900 mg IV q8h
  6. Strep = IVIG?
80
Q

List criteria for a positive tuberculin skin test

A
  • >5 mm in immunosuppressed, HIV, CXR abnormal
  • >10 mm in foreign-born, IVDU, HCWs, LTC residents
  • >15 mm everyone else
81
Q

What is the surviving sepsis 1-hour bundle?

A

SSC Hour-1 Bundle of Care Elements

  1. Lactate
  2. Blood cultures
  3. Antibiotics
  4. Crystalloid (30 mL/kg)
  5. Vasopressors for MAP >65

What international group has been critical of this approach?

  • American College of Emergency Physicians (ACEP)
82
Q

List FIVE causes of fever in a returning traveler

A
  1. Malaria (20-30%)
  2. Traveler’s diarrhea/Gastroenteritis (10-20%)
  3. Respiratory tract infections (10-15%)
  4. Dengue fever (5%)
  5. Enteric fever
83
Q

Who is at risk for a more severe course of influenza?

A
  1. Age >65
  2. Age <2
  3. Chronic lung disease (asthma, COPD)
  4. Chronic CV, renal, or hepatic disease
  5. Sickle cell anemia
  6. Diabetes
  7. Immunosuppression (steroids, HIV, etc.)
  8. Pregnancy
  9. Long-term ASA use
  10. Neuromuscular or seizure disorders
84
Q

What are the WHO criteria for a positive HIV diagnosis?

A

HIV Laboratory Criteria

  • Combination immunoassay that detects HIV-1 and HIV-1 antibodies and HIV-1 p24 antigen
  • If positive, goes on to differentiate HIV-1 from HIV-2
  • Nucleic acid testing if indeterminate
85
Q

What is the causative agent in botulism? What is the mechanism? List and describe the FIVE forms of botulism.

A

Botulism

Organism

  • Clostridium Botulinum

Mechanism

  • Neurotoxin binds peripheral NMJ + autonomic synapses
  • Binds presynaptic nerves & becomes internalize
  • Inhibits release of ACh

Symptoms

  • CN palsies
  • Parasympathetic blockade
  • Descending, flaccid paralysis

Types

  • Food-borne botulism
  • Ingestion of preformed heat-labile toxin
  • Not ingestion of spores or bacteria
  • Home-canned foods
  • Infant Botulism
  • Age <1 year (peak incidence = 2-6 months)
  • Ingestion of spores causing in vivo toxin production
  • Honey & corn syrup
  • Wound botulism
  • IVDU
  • Unclassified Botulism
  • Produces its toxin in vivo (rare illness)
  • Inadvertent botulism
  • Botox gone wrong
86
Q

What 5 criteria must be met for to give lyme prophylaxis

A
  1. Tick attached for >24h
  2. <72h since tick removed
  3. Right kind of tick (Ixodes scapularis)
  4. Endemic area
  5. No contraindications to doxycycline
87
Q

Define:

  1. Bacteremia (fungemia)
  2. SIRS
  3. qSOFA and what score is bad
  4. Sepsis
  5. Septic Shock
  6. How is organ dysfunction identified?
A

Bacteremia

  • Presence of bacteria/fungus in blood cultures

SIRS

  • 2+ of:
  • Temperature <36 or >38
  • WBC <4 or >12
  • RR >20 or PaCO2 <32
  • HR >90

qSOFA

  • Altered Mental status
  • RR >21
  • BP <100
  • 2+ predicts mortality and long ICU stay

Sepsis

  • Life-threatening organ dysfunction caused by a dysregulated host response to infection

Septic Shock

  • Sepsis requiring:
  • Vasopressors
  • Lactate >2 mmol/L without hypovolemia

Organ Dysfunction

  • Increase in SOFA score ≥2 due to infection
88
Q

What are 3 complications of chickenpox? What are 3 complications of shingles?

A

Chickenpox (HSV 3 = VZV)

  1. Bacterial superinfection
  2. Pneumonia
  3. Otitis media
  4. Encephalitis – diffuse vs acute cerebellar ataxia
  5. Aseptic meningitis
  6. Reye syndrome (ASA use)
  7. Hepatitis

Shingles

  1. Post-herpetic neuralgia (15%)
  2. Zoster ophthalmicus
    * Hutchinson’s sign
  3. Ramsay-Hunt Syndrome
  4. Reye Syndrome
    * Fatty liver + severe encephalopathy
  5. Necrotizing fasciitis
    * VZV + NSAIDS = RF of nec fasc
89
Q

Describe the typical child that gets infant botulism

A
  • Usually 2-6 months
  • Mom gave kid honey or corn syrup
  • Organic market and feed their kid honeycomb

Symptoms

  • Several days – weeks
  • Weak cry, loss of head control, hypotonia
  • Depressed DTRs, decreased tone on exam
  • CN involvement: facial expression, ptosis, EOM
  • Respiratory failure in 50%
90
Q

Define ARDS

A

Berlin Definition (2013)

  • Acute (within 1 week)
  • Bilateral patchy infiltrates
  • Not from cardiogenic pulmonary edema
  • P/F ratio <300 with PEEP 5 cmH2O

Severity

  • Mild (200-300)
  • Mortality 27%
  • Moderate (100-200)
  • Mortality 32%
  • Severe (<100)
  • Mortality 45%
91
Q

Provide FIVE DDx for respiratory diphtheria

A
  1. Gonorrhea
  2. Retropharyngeal abscess
  3. Tonsilitis
  4. Bacterial tracheitis
  5. Epiglottitis
  6. Vincent’s angina
92
Q

What are the first-line TB meds? List common side effects.

A

RIPE

  • Rifampin
  • Isoniazid (Give pyridoxine)
  • Pyrazinamide
  • Ethambutol

Pregnant TB = TREAT!

  • Don’t give pyrazinamide

Side Effects of TB Meds

Rifampin

  • Discoloration of body fluid (orange/red)

INH

  • Hepatotoxicity
  • Peripheral neuropathy
  • Use pyridoxine (B6) as treatment/prevention

Pyrazinamide

  • Hepatotoxicity
  • Polyarthralgias

Ethambutol

  • Retrobulbar neuritis and color-blindness
93
Q

What drugs can you prevent malaria with?

Preventing Malaria: A-B-C-D

  • Awareness of risk
  • Bite prevention
  • Chemoprophylaxis
  • Dx and Tx
A

Doxycycline 100 mg PO daily

  • Start 1 day before; continue 4 weeks after return

Mefloquine 250 mg PO weekly

  • Start 2.5 weeks before, continue 4 weeks after return

Malarone 1 tab PO daily

  • Start 1 day before; continue 1 week after returning
94
Q

List EIGHT risk factors for MRSA

A
  1. Immunocompromised (HIV, transplant, etc.)
  2. DM
  3. IVDU
  4. Fluoroquinolone use
  5. Young children
  6. Elderly
  7. Dormitories (College/Military)
  8. Jail
  9. HCWs
  10. African American, Native American, Pacific Islanders
  11. Tattoo Recipients
95
Q

Outline the diagnostic criteria for Staph TSS

A

Probable = Lab criteria + 4/5 clinical criteria

Confirmed = Lab criteria + 5/5 clinical criteria

Clinical Criteria

  1. Fever >38.9
  2. Diffuse macular erythematous rash
  3. Desquamation 1-2 weeks after the rash
  4. sBP <90
  5. 3+ organ systems:
    * GI: Vomiting/Diarrhea
    * MSK: Myalgia or CK >2x ULN
    * Renal: Cr or BUN >2x ULN
    * Hepatic: LFTs/Bili >2x ULN
    * Blood: Plt <100
    * Neuro: AMS
    * Derm: Mucous membranes red

Lab Criteria

  • BCx and CSF culture-negative (unless staph)
  • Measles, RMSF, Leptospirosis serology negative
96
Q

Outline the diagnostic criteria for Strep TSS

A
  1. Isolation of GAS
  2. Hypotension
  3. 2+ organ systems
    * Renal impairment
    * Coagulopathy
    * Hepatic dysfunction
    * ARDS
    * Erythematous rash
    * Soft tissue necrosis

Royal College: Emergency Medicine (25 decks)

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