Infectious Disease Flashcards
(48 cards)
1
Q
What is the classic triad of CNS infections?
A
- Fever
- Stiff neck
- Altered mental status
2
Q
When and Why should you do a CT of the head prior to LP? (4)
A
Why- r/o herniation through foramen magnum! When: - Pt has papilledema - Pt has seizures - Pt has focal neurological findings
3
Q
Nearly all bacterial meningitis pts have 2 of the following….(4)
A
- headache
- fever
- stiff neck
- altered mental status
4
Q
CNS Infection Evaluation (5)
A
- Infection- CBC, blood culture
- Meningitis- LP, CSF analysis
- CXR- pneumonia (looks like meningitis)
- Encapsulated organisms- latex agglutination
- Bacteria & virus- PCR or CSF
5
Q
What is the danger triangle of the face?
A
- Between the eyebrows, down over nose, to the sides of the mouth
- From the skin, to the facial vein, to superior ophthalmic vein, to cavernous sinus
6
Q
Cavernous Sinus Thrombosis (6)
A
- Infection of staph or strep S/S: - CN palsies - Meningeal irritation - Exophthalmos - CT for diagnosis - Ophtho/ENT EMERGENTLY
7
Q
Meningitis Overview (3)
A
- Infection involving the pia and arachnoid mater
- D/t: bacteria, virus, malignancy, chemical, protozoa, helminths, fungus
- Medical Emergency!
8
Q
S/S of Infectious Meningitis (6)
A
- headache
- fever
- sensory disturbances
- neck and back stiffness
- Kernig and Brudzinski’s sign
- CSF abnormalities
9
Q
Types of Meningitis (10)
A
- Purulent
- Chronic
- Aseptic
- Encephalitis
- Partially treated bacterial meningitis
- Neighborhood infection
- Non-infectious meningeal irritation
- Brain abscess
- Amebic meningoencephalitis
- Health care associated meningitis
10
Q
Purulent Meningitis (5)
A
- Acute, presents 1-2hrs of onset
- 18-50yrs= strep. pneumo., N. meningitidus
- Over 50= gram -, Listeria monocytogenes
- Diagnose with CSF culture or gram stain
- Tx with vanco + 2nd cephalosporin or ampicillin
11
Q
CNS Infection Tx (3)
A
- Abx prior to LP to avoid delay in tx
- LP done in 4 hrs of abx start
- Dexamethasone given to adults, most effective with strep
12
Q
Chronic Meningitis (3)
A
- Hx of symptoms for weeks or months
- Common pathogens are atypical (mycobacterium TB, spirochetes, etc….)
- Diagnosis is usually made by culture or serologic testing
13
Q
Aseptic Meningitis
A
- Usually d/t virus
- Benign, self-limiting
- Common viruses include: HSV, enteroviruses, EBV, etc…
14
Q
What are three drugs that can cause drug-induced aseptic meningitis?
A
- NSAIDS
- Sulfonamides
- Solid organ transplant agents- muromonab, CD3 (OKT3)
15
Q
Partially Treated Bacterial Meningitis (4)
A
- Appears similar to aseptic meningitis on CSF evaluation
- Happens when pt comes off abx too soon
- May not have the same bacterial count as before
- May look different in CSF from the first time
16
Q
Neighborhood Rxn Meningitis (7)
A
- Purulent infectious process close to CNS
- Spills inflammatory products into CSF
Caused by: - Brain abscess
- Osteomyelitis of the vertebrae
- Epidural abscess
- Subdural Empyema
- Bacterial sinusitis or mastoiditis
17
Q
Noni Infectious Meningeal Irritation (8)
A
Caused by: - Carcinomatous meningitis - Sarcoidosis - SLE - Chemical Meningitis - Drugs - Signs of meningeal irritation i.e. headache CSF shows - increased protein level - low or normal glucose level - increased cells (pleocytosis)
18
Q
What are the 2 types of Amebic Meningoenchephalitis
A
- Diagnosis confirmed by culture
- 2 distinct syndromes:
1. Primary
2. Granulomatous amebic encephalitis
19
Q
Primary Amebic Meningoencephalitis (3)
A
- N. fowleri
- Children, young adults
- acute, fulminant dz, rapid progression to death
20
Q
Granulomatous Amebic Encephalitis (5)
A
- Acanthamoeba, Balamuthia
- indolent dz
- immunocompromised
- cutaneous lesions
- headache, N/V, seizures, hemiparesis
21
Q
Health Care associated Meningitis (6)
A
Caused by: - invasive neuro surgery - complicated head trauma - hospital acquired blood stream infection Typical organism: - pseudomonas - Staph - Coag neg staph
22
Q
Encephalitis (3)
A
- inflammation of brain
- caused by a virus i.e. HSV, etc…
- Pt more ill than with viral meningitis
23
Q
Symptoms of Encephalitis (2)
A
- Sensory disturbances
- Seizures
24
Q
Diagnosis of Encephalitis (2)
A
- CSF may be normal or show lymphocytes
- CSF may show RBC in cases of HSV
25
Brain Abscess Overview (3)
- Arise as sequela of dz of the ear, nose, or an infection elsewhere
- Arise from surgical intervention or trauma
- Common organisms: staph, strep, anaerobes
26
Early S/S of Brain Abscess (5)
- Headache
- Drowsiness
- Inattention
- Confusion
- Seizures
27
S/S of Late Brain Abscess (2)
- Increasing ICP
| - Focal neurological deficit
28
Brain Abscess Imaging (2)
CT- area of contrast enhancement surrounding a low density core
MRI with and w/out contrast- more sensitive, catch it earlier
29
Procedures for Brain Abscess (4)
- Stereotactic needle aspiration allows drainage and culture (if they are >2cm)
- CSF not helpful
- LP contraindicated d/t herniation
- Serum leukocytosis may be present
30
Brain Abscess Tx (4)
- IV abx for 6-8wks
- Followed by oral abx for 2-3 months
- PCN G + 3rd cephalosporin + metronidazole
- add Nafcillin if staph is suspected
31
Brain Abscess F/U (2)
- CT/MRI every 2 weeks or if symptoms worsen
| - Reduce edema with dexamethasone or mannitol
32
Lyme Dz Overview (4)
```
- B. burgdorfer in CNS + PNS
Early CNS manifestations include:
- headache
- fever
- neck stiffness
```
33
What is neuroborreliosis? (6)
- Late finding in Lyme Dz
- Subtle changes in memory
- Hx of erythema migrans or arthritis
- encephalopathy prompting CSF evaluation
- CSF may show elevated protein/pleocytosis
- Serology positive
34
Lyme's Dz Peripheral Neuropathy (4)
- Facial Nerve Palsy
- Abnormal EMG
- Abnormal nerve biopsy- perivascular lymphocytes
- Positive serology
35
Lyme's Dz Tx (4)
```
Facial Nerve Palsy:
- doxycycline
- amoxicillin/cefuroxime
CNS:
- Ceftriaxone
- PCN G/ Cefotaxime IV
```
36
Neurosyphilis (4)
- Can occur at any stage of infection
- Progressive, disabling, life threatening
- Meningovascular syphilis occurs early
- Tabes dorsalis & general paresis occur late
37
Asymptomatic Neurosyphilis (4)
CSF abnormalities:
- increased protein
- lymphocytic pleocytosis
- + CSF reagin test
- No neurologic findings
38
Meningovascular Syphilis (8)
- Meningial involvement
- Changes in vasculature of brain
- S/S of acute/chronic meningitis
- cranial nerve palsies
- unequal reflexes
- MLF involvement
- CSF abnormalities
- + serology
39
Tabes Dorsalis Definition
Degeneration of dorsal columns of spine and posterior sensory and nerve roots
40
Tabes Dorsalies S/S (8)
- impairs prop/FT/vib
- Muscle hypotonia & hyporeflexia
- Wide based gait
- argyll-robertson pupil
- parasthesia/analgesia/ shooting pain
- neurogenic bladder
- painless ulcers
- joint damage (charcot foot)
41
What is the Tabes Dorsalis "crises"? (5)
- lasts for hours to days then stops
- gastric crises (sharp abd. pain, N/V)
- laryngeal crisis (cough, dyspnea)
- urethral crises (bladder spasms)
- rectal/anal crises (pain)
42
General Paresis (8)
- involves cerebral cortex
- decrease in concentration
- memory loss
- dysarthria
- tremors of the fingers and lips
- irritability
- mild headaches
- personality change (irresponsible, confused, psychotic)
43
TB Meningitis (7)
- M. tuberculosis
* *gradual onset
- listlessness/irritability/anorexia
- headache, vomiting, seizure
- CN abnormalities
* *TB elsewhere in the body
* *CSF shows lymphocytic pleocytosis, low glucose, high protein
44
TB Meningitis Tx (3)
* *All anti TB meds penetrate BBB
- rifampin + isoniazid + pyrazinamide + ethambutol
- add corticosteroids if focal deficits/altered mental status
45
HSV Encephalitis Presentation (7)
- Fever
- Headache
- Psychiatric symptoms
- Seizures
- Vomiting
- Focal Weakness
- Memory loss
46
HSV Encephalitis Diagnosis (5)
- CSF pleocytosis
* *RBC's in CSF
- PCR on CSF
- MRI shows increased signal in temporal and frontal lobes
- EEG may show temporal lobe seizure foci
47
HSV Encephalitis Tx (4)
- IV acyclovir
- not really toxic but watch the kidneys
- long term neurologic sequellae are common
- late pediatric relapse is recognized
48
Creutzfeld-Jakob Dz
- transmissable spongiform encephalopathies (TSE)
- Several forms
- Starts with forgetfulness, discoordination
- progressive over a short time to coma and death
