CNS Infections part 1 Flashcards

1
Q

What is the most common route for CNS infections to arise?

A

Hematogenous (via blood)

– usually arterial

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

What are the 4 ways that a CNS infection can reach the CNS?

A
  1. Hematogenous
  2. Direct Implantation
  3. Local extension
  4. Peripheral Nervous System
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

What are the only 2 organisms that reach the CNS via infecting the peripheral nervous system and moving to the CNS?

A

Rabies

Herpes Zoster

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

What is the importance of the CSF being completely exchanged in the brain every 3-4 hours with CNS infections?

A

Completely bathes the brain in the bacteria!

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

Which organism uses direct seeing from a subepidural or submeningeal granuloma to infect the CNS?

A

Tuberculus Meningitis

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

Describe how Rabies infects the CNS

A

Virus binds the Ach receptors at the NMJ and ascends motor neurons to the CNS

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

Describe how Herpes Zoster infects the CNS

A

Infects sensory ganglia and replicates in schwann cells and ascends to CNS via sensory nerves

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

Capillaries in the BBB are impermeable to what types of things?

A

Antibiotics
Complement
Immunoglobulins

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

How do molecules cross the BBB capillaries?

A

Active transport

Lipid soluble

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

Which populations are at the highest risk for Meningitis?

A

< 5
> 60
Diabetics
Immunosuppressed

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

A lumbar puncture is performed to diagnose Meningitis. What organism is commonly Gram (-) Diplococci in the CSF?

A

N. Meningitidis

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

A lumbar puncture is performed to diagnose Meningitis. What organism is commonly Gram (+) Diplococci in the CSF?

A

S. Pneumoniae

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

A lumbar puncture is performed to diagnose Meningitis. What organism is commonly Gram (-) pleomorphic in the CSF?

A

H. Influenzae

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

A lumbar puncture is performed to diagnose Meningitis. What organisms are commonly Gram (+) Cocci?

A

S. Aureus

Streptococci

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

A lumbar puncture is performed to diagnose Meningitis. What organism is commonly Gram (-) Bacilli in the CSF?

A

E. Coli

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

What are some symptoms of Meningitis?

A

Meningeal irritation - fever, headache, N/V, confusion, stiff neck

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

What is the CNS response to pyogenic (bacterial) meningitis?

A

Cerebral Edema (loss of BBB)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
18
Q

Cerebral edema is the CNS response to pyogenic meningitis. What accelerates it and what slows/resolves it?

A

Accelerated by = Bacteria

Slowed/Resolved by = Corticosteroids

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

CSF appearance for Bacterial vs Viral Meningitis?

A

Bacterial - cloudy/turbid

Viral - clear

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

CSF lab value of Neutrophils/Lymphs/Monos for Bacterial vs. Viral Meningitis?

A

Bacterial - NEUTROPHILS

Viral - Lymphs/Monos

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

CSF lab value of Glucose for Bacterial vs. Viral Meningitis?

A

Bacterial - LOW glucose

Viral - normal glucose

22
Q

Protein may be increased in the CSF with Meningitis. Bacterial vs. Viral, which causes a greater increase?

A

Bacterial

23
Q

In the CSF, if the glucose is < 50, what is the likely cause of the Meningitis?

A

BACTERIA

24
Q

In a neonate, what are the likely organisms causing pyogenic meningitis?

A

E. Coli OR

Group B Streptococcus

25
Q

In a child < 2 years old that is UNvaccinated, what is the likely organism causing pyogenic meningitis?

A

H. Influenzae type B

26
Q

In a young adult, what is the likely organism causing the pyogenic meningitis?

A

N. Meningitidis

27
Q

In the elderly, what is the likely organism causing pyogenic meningitis?

A

Strep. Pneumoniae

28
Q

Waterhouse Friderichsen Syndrome can be a complication of Meningitis. What are the symptoms and what are 2 organisms that commonly cause it?

A

Rash, Adrenal Hemorrhage, death

- Meningococcemia and N. Meningitidis

29
Q

Chemical Meningitis

A

NON-bacterial irritant in the subarachnoid space

30
Q

Brain Abscesses arise via the same routes as Meningitis does. What are the symptoms of Brain Abscesses?

A

Progressive focal neuro deficits

Possible increase in intracranial pressure

31
Q

What are the CSF values for WBC, protein and glucose for Brain Abscesses?

A

Increased WBC and protein

Normal glucose

32
Q

What are 2 complications of a Brain Abscess?

A

Abscess rupture with infection

Venous sinus thrombosis and patient dies

33
Q

What is a Subdural Empyema and what change in the dura is seen?

A

Infections of the skull bones or sinuses that spreads to the subdural space
– Thickened Dura

34
Q

What is associated with an Extradural Abscess?

A

Osteomyelitis

35
Q

Osteomyelitis is associated with? And what may it cause?

A

Extradural Abscess

– may cause cord compression

36
Q

Neisseria Meningitidis colonizes ____ and spreads via _____

A

Colonizes asymptomatic carries

Spreads via direct contact with respiratory secretions

37
Q

Neisseria Meningitidis infections are common in what populations?

A

Dorms, military quarters all in close contact

38
Q

What are the signs of infection with N. Meningitidis?

A

Fever, septicemia, DIC, petechial lesions and purpura fulminans

39
Q

What is purpura fulminans and what infection is it seen with?

A

Hemorrhage skin lesions that turns into gangrene of the distal limbs
– N. Meningitidis

40
Q

What classifies Chronic Meningitis and what CSF changes for protein, cell type and glucose levels are present?

A

CSF abnormalities and symptoms for > 4 weeks

Increased protein, lymphs and decreased glucose

41
Q

What 3 organisms can cause Chronic Meningitis?

A
Tuberculosis
Borellia Burgdorferi (lyme disease)
Treponema Pallidum (syphilis)
42
Q

With Chronic Meningitis, TB and Neurosphilis have a predilection to form exudates where in the brain?

A

BASE (arachnoiditis)

43
Q

If Mycobacterium Tuberculosis is causing the Chronic Meningitis, what mass may be present and why could there be CN signs?

A

Tuberculoma - caseous necrosis mass

– exudate at base of brain traps CN’s and obliterates cisterns

44
Q

If Borrelia Burgdorferi is causing the Chronic Meningitis, what are the symptoms?

A

Rash
* 4 weeks pass*
Cranial nerve palsies and peripheral neuropathies

45
Q

With Borrelia Burgdorferi, what is in the CSF that can cross react?

A

Antibodies

46
Q

What are the 3 types of Neurosyphilis (Treponema Pallidum)?

A
  1. Meningovascular Neurosyphilis
  2. Paretic Neurosyphilis
  3. Tabes Dorsalis
47
Q

What are the 3 types of Neurosyphilis?

A
  1. Meningovascular Neurosyphilis
  2. Paretic Neurosyphilis
  3. Tabes Dorsalis
48
Q

Meningovascular Neurosyphilis

A

Chronic meningitis involving the base of the brain

+ communicating hydrocephalus

49
Q

Paretic Neurosyphilis

A

Progressive mental deficits with mood alterations that terminate in severe dementia
+ iron deposits

50
Q

Tabes Dorsalis

A

Damage to sensory nerves

  • Loss of pain sensation, DTRs, limb awareness
  • Joint damage and lightening pains