CNS/Opthalmic Infections Flashcards

You may prefer our related Brainscape-certified flashcards:
0
Q

3 causes of bacterial meningitis in the neonate

A
  1. E. coli
  2. GBS
  3. Listeria monocytogenes
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
1
Q

Common causes of viral meningitis

A
  1. Enteroviruses (coxsackieviruses, echoviruses)

2. Herpesviruses

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

Causes of bacterial meningitis in adults

A
  1. S. pneumoniae
  2. N. meningitidis
  3. H. influenzae
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

Patho of bacterial meningitis

A
  1. Nasopharyngeal colonization
  2. Local invasion
  3. Bacteremia
  4. Endothelial cell injury
  5. Increased BBB permeability + meningeal invasion
  6. Subarachnoid space inflammation -> cerebral vasculitis
  7. Problems
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

Complications of bacterial meningitis

A
  1. Edema (vasogenic, interstitial, cytotoxic) results in increased ICP
  2. Increased ICP leads to decreased cerebral blood flow –> death
  3. Cerebral vasculitis can cause cerebral infarction, which may also decrease cerebral blood flow, causing death
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

Classic triad of meningitis

A
  1. Fever
  2. Neck stiffness
  3. Headache
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

Clinical Sx associate with meningitis

A
  1. Photophobia
  2. N/V
  3. Petechial rash = meningococcal meningitis
  4. Neurological symptoms (seizures etc.)
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

Findings suggestive of meningitis on physical exam

A
  1. Fever
  2. Petechial rash
  3. Neck stiffness
  4. Kernig sign
  5. Brudzinski sign
  6. Increased headache with jolt
  7. Cranial nerve palsies
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

What is Kernig’s sign?

A

Resistance or pain in lower back or posterior thigh when the knee is extended (when hip flexed to 90 degrees)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

What is Brudzinski’s sign?

A

When passive neck flexion in the supine pt results in flexion of the knees and hips

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

What is papilledema?

A

Blurring of the edges of the optic disk, which indicates increased ICP

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

What investigations might you perform for suspected meningitis?

A
  1. LP to obtain CSF for: WBC diff, protein, glucose, Gram stain, culture
  2. CT or MRI head
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

When is a head CT indicated prior to doing a LP?

A

Concerned about increased ICP, where LP leads to cerebral herniation and death

  • Immunocompromised state
  • Focal neuro deficits
  • Hx of CNS disease
  • New onset seizures
  • Papilledema
  • Altered LOC
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

Tx of meningitis

A
  1. Start antibiotics ASAP
  2. If LP delayed, do blood cultures and start antibiotics
  3. Empiric Tx = Ceftriaxone + Vancomycin
  4. Can also add Ampicillin and/or dexamethasone
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

What is the prognosis for meningitis?

A
  1. Overall 15% mortality

2. 28% have neuro complications

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

What differentiates meningitis from encephalitis?

A

Encephalitis presents with brain function abnormalities, such as:

  1. Altered LOC
  2. Motor or sensory deficits
  3. Change in behaviour/personality
  4. Speech or mvmt disorder
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

Infectious causes of encephalitis

A
  1. Viral: HSV-1 (life threatening), VZV, other herpes viruses, Arboviruses, Enteroviruses, Measles
  2. Non-viral: tick-borne, bacteria, protozoa
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
17
Q

Clinical presentation of encephalitis

A
  1. Fever
  2. Headache
  3. Altered mental status
  4. Seizures
  5. +/- rash
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
18
Q

Dx approach to encephalitis

A
  1. LP and CSF analysis (culture, WBC, protein, glucose)
  2. PCR the CSF sample
  3. Serology for Arboviruses
  4. Brain biopsy as last resort
  5. CT head or MRI
  6. EEG
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
19
Q

Tx for encephalitis

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

Risk factors for a brain abscess

A
  1. Immunosuppression
  2. Chronic cardiopulmonary conditions
  3. Penetrating head trauma
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
21
Q

Cause of brain abscess

A
  1. Immunocompetent = polymicrobial

2. Immunocompromised = Toxoplasmosis, Cryptococcus, TB

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

Clinical presentation of brain abscess

A
  1. Headache
  2. Fever
  3. Focal neuro deficits - dependent on location in brain affected
  4. Change in mental status
  5. Seizures
  6. N/V
  7. Neck stiffness
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
23
Q

How to Dx a brain abscess

A
  1. CBC - normal WBC

2. CT scan with contrast or MRI

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

Tx for brain abscess

A
  1. Aspiration
  2. Ceftriaxone + Metronidazole +/- Vancomycin, OR
  3. Meropenem +/- Vancomycin
  4. Dexamethasone when significant swelling
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
25
Q

Risk of epidural abscess?

A

Can expand and compress the spinal cord, leaving neuro complications

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
26
Q

Risk factors for epidural abscess

A
  1. Manipulation of epidural space
  2. Spread from other infection
  3. IVDU
  4. DM, alcoholism, HIV
  5. Trauma
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
27
Q

Top 4 causes of epidural abscess

A
  1. S. aureus
  2. Gram -ve bacilli
  3. Streptococci
  4. CNS
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
28
Q

Patho of epidural abscess

A

Damage to spinal cord from:

  1. Direct compression
  2. Cutting of blood supply
  3. Bacterial toxins and inflammatory mediators
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
29
Q

Clinical presentation of epidural abscess

A

Initially non-specific (fever and malaise)

Classic triad = Fever, back pain, neuro deficits

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
30
Q

Progression of untreated epidural abscess

A

Back pain -> nerve root pain -> motor weakness, sensory changes, bladder or bowel dysfunction -> paralysis

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
31
Q

Preferred Dx imaging for epidural abscess

A

MRI (can use CT, but X-ray not very good)

32
Q

Specimen collection for Dx of epidural abscess

A
  1. Abscess content
  2. Blood
  3. CSF
33
Q

Management of epidural abscess

A
  1. Surgery and drainage

2. Antibiotics, empiric Tx = Ceftriaxone + Metronidazole + Vancomycin

34
Q

Prognosis of epidural abscess

A
  1. 5% mortality

2. 4-22% irreversible paraplegia

35
Q

What are the viral causes of conjunctivitis?

A
  1. Adenoviruses

2. Enteroviruses (and coxsackieviruses)

36
Q

Clinical presentation of viral conjunctivitis (AKA pink eye)

A
  1. Watery discharge (morning crust of eyebrows)
  2. Irritation
  3. Burning/itching of eyes
  4. Conjunctival hyperemia
  5. Conjunctival edema (chemosis)
37
Q

Key negatives for viral conjunctivitis

A
  1. No eye pain

2. Vision not affected

38
Q

Adenoviral conjunctivitis is associated with what 2 clinical manifestations

A
  1. Pharyngoconjunctival fever

2. Epidemic keratoconjunctivitis

39
Q

What is the clinical presentation of pharyngoconjunctival fever?

A
  1. Pharyngitis
  2. Fever
  3. Conjunctivitis
  4. Pre-auricular adenopathy
40
Q

Clinical presentation of keratoconjunctivitis

A
  1. Subconjunctival bleeding

2. Conjunctival membranes

41
Q

Epidemic keratoconjunctivitis

A
  1. Inflammation of conjunctivitis and cornea
  2. May be vision threatening
  3. Lasts 1-3 weeks
42
Q

Dx of viral conjunctivitis

A
  1. Clinical

2. Viral swab for PCR

43
Q

Tx of viral conjunctivitis

A
  1. Cold compress, eye lubricant drops, decongestant eye drops
  2. May be excluded from school/work, should resolve within 2 wks
  3. Epidemic keratoconjunctivitis needs opthalmology referral
44
Q

Prevention of viral conjunctivitis

A

HIGHLY contagious

  1. Frequent hand washing
  2. Avoid sharing towels, eye drops, eye make up, contact lens solution
  3. Proper sterilization of clinic instruments
45
Q

Top 4 pathogens that cause acute bacterial conjunctivitis

A
  1. S. aureus
  2. S. pneumoniae
  3. H. influenzae
  4. GAS
46
Q

Clinical presentation of acute bacterial conjunctivitis

A
  1. Redness in eye
  2. Greenish-yellow discharge (matted eyelids)
  3. Conjunctival hyperemia
  4. Eyelid swelling
47
Q

Clinical presentation of hyperacute bacterial conjunctivitis caused by N. gonorrhea

A
  1. PROFUSE purulent discharge
  2. Chemosis, hyperemia, and eyelid edema
  3. Severe - vision threatening
  4. Transmitted from genitals to hands to eyes
  5. Send to Opthalmologist
48
Q

What is the most common cause of preventable blindness in the world?

A

C. trachomatis (chlamydial conjunctivitis)

49
Q

Dx bacterial conjunctivitis

A
  1. Clinical

2. Culture eye discharge

50
Q

Prophylaxis for gonococcal conjunctivitis in the newborn

A

Erythromycin ointment

51
Q

Tx for opthalmia neonatorum

A
  1. N. gonorrhea = Ceftriaxone IV

2. C. trachomatis = Erythromycin

52
Q

Tx of gonococcal and chlamydial conjunctivitis in adults

A
  1. Gonococcal = Ceftriaxone IV/IM

2. Chlamydial = Doxycycline PO

53
Q

What are red flags for an opthalmogy referral?

A
  1. Reduced vision
  2. Photophobia
  3. Severe foreign body sensation
  4. Corneal opacity
  5. Severe headache and nausea
54
Q

What is keratitis?

A

Inflammation of the cornea

55
Q

Patho of keratitis

A
  1. Disrupted corneal epithelium
  2. Entrance of microbes to corneal stroma
  3. Microbe proliferation –> ulcerations
  4. Infected epithelium and stroma swell and become necrotic
  5. May lead to inflammation in anterior chamber (hypopyon)
56
Q

Risk factors for keratitis

A
  1. Prolonged wear of contact lenses
  2. Eye trauma
  3. Eye surgery
  4. Chronic ocular surface disease
  5. DM
  6. Topical corticosteroids
57
Q

Bacterial causes of keratitis

A
  1. S. aureus
  2. S. pneumoniae
  3. GAS
  4. Gram -ve organisms
58
Q

Viral, fungi, and parasitic causes of keratitis

A
Viral = HSV-1, adenovirus, VZV
Fungi = Fusarium spp.
Parasites = Acanthamoeba spp.
59
Q

Clinical presentation of keratitis

A
  1. Eye pain
  2. Decreased vision
  3. Foreign body sensation
  4. Photophobia
  5. Tearing and discharge
  6. Corneal infiltrate or ulcer (change in transparency)
  7. SEND to Opthalmologist
60
Q

Dx of keratitis

A
  1. Slit lamp exam

2. Corneal scrapings (bacterial/viral/fungal culture, PCR, staining/microscopy)

61
Q

Tx for bacterial keratitis

A
  1. Non-contact user = fluoroquinolone drops

2. Contact user = aminoglycoside + pipercillin drops

62
Q

Tx for viral keratitis

A
  1. Trifluridine drops or Acyclovir ointment
63
Q

Difference btw conjunctivitis and keratitis

A
  1. Moderate to severe eye pain with keratitis
  2. Reduced vision with keratitis
  3. Hazy cornea with keratitis
64
Q

What is endopthlamitis?

A

Infection of the vitreous and/or aqueous humors

65
Q

Clinical presentation of endopthalmitis

A
  1. Decreasing vision
  2. Eye ache
  3. Conjunctiva may be edematous
  4. Hypopyon
66
Q

Dx for endopthalmitis

A
  1. Aspiration of aqueous and vitreous humor
  2. Vitrectomy
  3. Send sample for culture
67
Q

Causes of endopthalmitis

A
  1. CNS
  2. S. aureus
  3. Streptococci
  4. Gram -ve organisms
  5. Candida spp.
68
Q

Tx for endopthalmitis

A

This is an emergency

  1. Intravitreal antibiotics (Vancomycin + Ceftazidime)
  2. Vitrectomy (severe)
  3. Systemic antibiotics (severe)
69
Q

What is periorbital cellulitis?

A

Infection of the anterior portion of the eyelid

70
Q

What might lead to periorbital cellulitis?

A
  1. Local trauma (bites, surgery, foreign body)
  2. URTI
  3. Dacrocystitis
  4. Sinusitis
71
Q

What are infectious causes of periorbital cellulitis?

A
  1. S. aureus
  2. S. pneumoniae (and other strep)
  3. Anaerobes
  4. H. influenzae
72
Q

Clinical presentation of periorbital cellulitis

A
  1. Ocular pain
  2. Eyelid swelling
  3. Erythema
73
Q

How to Dx periorbital cellulitis

A
  1. Hx
  2. Physical (full eye ROM, no double vision, no increase in pain with eye mvmt, no eye bulging)
  3. CT of orbits and sinuses
74
Q

Tx for periorbital cellulitis

A
  1. Clindamycin OR

2. TMP-SMX + Amoxicillin (or amox-clav)

75
Q

Clinical presentation of orbital cellulitis

A
  1. Ocular pain
  2. Eyelid swelling with redness
  3. Pain with eye mvmt
  4. Proptosis (eye bulging)
  5. Limitation of eye mvmt (opthalmoplegia)
  6. Double vision
  7. Fever
  8. Chemosis
76
Q

What are 2 complications of orbital cellulitis?

A
  1. Vision loss

2. Brain abscess

77
Q

How to Dx orbital cellulitis

A
  1. Blood or surgical cultures
  2. Imaging (CT or MRI of orbits/sinuses): inflammation of extraocular muscles, fat stranding, and anterior displacement of the eye
78
Q

Tx for orbital cellulitis

A
  1. Vancomycin IV + Pip-taz IV
  2. Vancomycin IV + Ceftriazone IV/Cefotaxime IV
  3. Surgery for poor response to antibiotics, worsening vision, or abscess