Brainscape's Knowledge GenomeTM

Browse over 1 million classes created by top students, professors, publishers, and experts.


See full index

Neurology > Infections of the Nervous System > Flashcards

Infections of the Nervous System Flashcards

1
Q

Untreated infection may cause

A

-Brain herniation and death -Cord compression and necrosis with subsequent permanent paralysis

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

What are the different types of meningitis?

A
  • acute pyogenic (bacterial) - acute aseptic (viral) - acute focal suppurative infection (brain abscess, subdural and extradural empyema) - chronic bacterial infection (tuberculosis)
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

What is acute encephalitis?

A

Infection of the brain parenchyma

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

Describe macroscopic pyogenic meningitis

A

Thick layer of suppurative exudate covers the leptomeninges over the surface of the brain. Exudate in basal and convexity surface

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

Describe microscopic pyogenic meningitis

A

Neutrophils in subarachnoid space

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

What are the common organisms causing bacterial meningitis - community acquired

A

pneumococcus

meningococcus

haemophilus influenzae

occasionally other gram -ve

Listeria

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

What is the treatment for bacterial meningitis - community acquired

A

Ceftriaxone IV 2g bd

(penicillin allergy: chloramphenicol IV 25mg/kg qds)

+

Dexamethasome IV 10mg qds

(3ml of 3.3mg/ml dexamethasome base injection)

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

What is the treatment for CA bacterial meningitis if listeria cover is needed?

A

If listeria cover required add;

Amoxicillin IV 2g 4 hourly to ceftriaxone & dexamethasone

(penicillin allergy: co-trimoxazole IV 120mg/kg divided into 4 doses/day)

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

What is the treatment for bacterial CA meningitis if recent travel (within last 6 months) to country with high rates of penicillin resistant pneumococcus then add;

Vancomycin IV (aim for predose level 15-20mg/L) or Rifampicin IV/PO 600mg bd

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

Which countries have high rates of pneumococcal resistance?

A
  • canada
  • china
  • croatia
  • pakistan
  • poland
  • spain
  • mexico
  • italy
  • USA
  • greece
  • turkey
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

What is the duration of treatment for bacterial CA meningitis if no organism is identified?

A

no organism identified: 10 days if patient has clinically recovered

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

What is the treatment duration for CA meningococcal bacterial meningitis

A

5 days ceftriaxone (if patient not recovered by 5 days extend course to 7 days initially and review) + stop dexamethasone

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

What is the treatment duration for CA pneumococcal bacterial meningitis

A

10 days ceftriaxone (if patient taking longer to respond extend course up to 14 days) + 4 days dexamethasone

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

What is the treatment duration for CA penicillin/cephalosporin resistant pneumococcal bacterial meningitis

A

14 days ceftriaxone + vancomyxin (vancomyxin monotherapy not recommended due to concerns re CSF penetration) + 4 days dexamethasone

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

What is the treatment duration for CA listeria bacterial meningitis

A

at least 21 days amoxicillin + stop dexamethasone

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

What is the treatment duration for CA haemophilus influenzae bacterial meningitis

A

10 days of ceftriaxone + stop dexamethasone

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

What is the treatment duration for CA gram negative bacterial meningitis

A

21 days of antibiotic regime agreed with ID/micro + stop dexamethasone

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

When is viral meningitis common?

A

Late summer/autumn

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

How is viral meningitis diagnosed?

A

Viral stool culture, throat swab, CSF PCR

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

What is the treatment for viral meningitis?

A

Supportive

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

If you suspect a patient has viral encephalitis what should be done?

A

Assess ABCD and check glucose (+/- involve ICU)

If no contraindication ot lumbar puncture then LP; if contraindication then urgent CT

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

What are the contraindications for LP

A

Significant brain shift/swelling

TIght basal cisterns

Alternative diagnosis made

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
23
Q

What should be checked on the LP?

A

Opening pressure

CSF and serum glucose

CSF protein

2 x MC & S

Virology PCR

Lactate

consider paired oligoclonal bands

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

What should be done if the delay before LP results are pending is >6 hours

A

Start IV aciclovir

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
25
Q

What should be done after urgent CT if contraindication to LP?

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

If CSF findings dont suffest encephalitis what should be done?

A

Repeat LP every 24-48 hrs

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

If HSV/VZV encephalitis confirmed then what should be done?

A

if immunocompromised or aged 3 months- 12 years: 21 days IV aciclovir

If not 14 days IV aciclovir

  • Repeat LP*
  • If still +ve then 7 days IV aciclovir*
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
28
Q

What questions should be considered in a history assessing a patient with suspected encephalitis?

A
  • Current or recent fibrile or influenza-like illness?
  • Altered behaviour or cognition, personality change or altered consciousness?
  • New onset seizures?
  • Focal neurological symtpms?
  • Rash? (VZ, roseola, enterovirus)
  • Others in family, neighbourhood ill? (measles, mumps, influenza)
  • Travel history (prophylaxis and exposure for malaria, arboviral encephalitis, rabies, trypanosomiasis)
  • recent vaccination? (ADEM)
  • contact with animals (rabies)
  • contact with fresh water? (leptospirosis)
  • exposure to mosquito or tick bites (arboviruses, lyme disease, tick-borne encephalitis)
  • known immunocompromise
  • HIV risk?
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
29
Q

What are the clinical features of encephalitis?

A
  • insidious onset; sometimes sudden
  • meningismus
  • stupor, coma
  • seizures, partial paralysis
  • confusion, psychosis
  • speech, memory symptoms
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
30
Q

What are the common signs + symptoms of meningitis and septicaemia?

A
  • fever
  • headache
  • vomiting
  • diarrhoea
  • muscle pain
  • stomach cramps
  • fever with cold hands and feet
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
31
Q

What are some common signs of meningitis?

A
  • fever, cold hands and feet
  • vomiting
  • drowsy, difficult to wake
  • confusion and irritability
  • severe muscle pain
  • pale, blotchy skin- spots/rash
  • severe headache
  • stiff neck
  • dislike bright lights
  • convulsions/seizures
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
32
Q

What is the cause of CA bacterial meningitis in neonates?

A

Listeria, group B streptocicci, e. coli

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
33
Q

What is the cause of CA bacterial meningitis in children?

A

H. influenza

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
34
Q

What is the cause of CA bacterial meningitis in ages 10 to 21?

A

Neisseria meningitidis

35
Q

What is the cause of CA bacterial meningitis in age over 21?

A

Streptococcus pneumoniae > neisseria meningitidis

36
Q

What is the cause of CA bacterial meningitis in age >65?

A

Streptococcus pneumoniae > listeria

37
Q

What is the most likely cause of CA bacterial meningitis in a patient with the following risk factors;

  1. Decreased cell mediated immunity?
  2. Neurosurgery/head trauma?
  3. Fracture of the cribiform plate?
A
  1. listeria monocytogenes
  2. staphylococcus, gram negative bacilli
  3. Streptococcus pneumoniae, h. influenza, beta haemolytic strep group A
38
Q

What is the most likely cause of bacterial meningitis post head trauma or CSF shunt?

A

Head trauma: s. aureus, s. epidermidis, aerobic GNR

CSF shunt: s. epidermidis, s. aureus, aerobic GNR, propionibacterium acnes

39
Q

What life altering affects may arise as a result of meningitis/septicaemia?

A

Limb loss, deafness, blindess, cerebral palsy, quadriplegia, severe mental impairment

40
Q

What are some of the consequences of purulent bacterial meningitis?

A

Clusters at the base of the brain

Convexities of rolandic and sylvian sulci

Exudate around nerves (III, VI cranial nerves particularly vulnerable)

41
Q

What are the consequences of invasion of bacterial meningitis?

A

Pia prevents meningitis becoming abscess

Abscesses can cause secondary ventriculitis and henxy meningitis

42
Q

What are the complications of meningitis?

A
  • purulence
  • invasion
  • cerebral oedema
  • ventriculitis/hydrocephalus
43
Q

Describe the pathogenesis of bacterial meningitis?

A
  1. nasopharyngeal colonisation
  2. direct extension of bacteria
    * ​parameningeal foci (sinusitis, mastoiditis, or brain abscess)*
    * across skull defects/fracture*
  3. from remote foci of infection
    * endocarditis, pneumonia, UTI*
44
Q

what kind of causative agents of bacterial meningitis may be seen in patients with CD4 <100

A

Cryptococcus neoformans

45
Q

How do n. meningitidis access the meninges?

A

through the bloodstream

46
Q

What are the symptoms of meningococcal meningitis a result of?

A

Endotoxin

47
Q

How are military recruits prevented from meningococcal meningitis

A

Vaccinated with purified capsular polysaccharide

48
Q

What is the mortality rate of meningitis with septicaemia?

A

15%

49
Q

There are ___ types of H.influenzae based on capsule differences

H. influenzae type _ is the most common cause of meningitis in children under _

A

There are six types of H.influenzae based on capsule differences

H. influenzae type b is the most common cause of meningitis in children under 4

50
Q

How can haemophilus influenzae be prevented?

A

A conjugated vaccine directed against the capsular polysaccharide antigen is available

51
Q

Who is most susceptible to s. pneumoniae menigitis?

A

Hospitalised patients, patients with CSF skull fractures, diabetics/alcoholics and young children are most susceptible to s. pneumonia meningitis

52
Q

How can pneumococcal pneumonia be prevented?

A

New conjugate vaccine for pneumococcal pneumonia also provides protection against pneumococcal meningitis [in children]

53
Q

Listerial monocytogenes;

Gram _____ _____ (_ blood cultures)

______ but on rise

Mainly _______ illness

_____ and > __ years or _________ especially malignancy

Antibiotics of choice;

__ ______/________

________ no value as intrinsically resistant

A

Listerial monocytogenes;

Gram positive bacilli (+ blood cultures)

Sporadic but on rise

Mainly bacteraemic illness

Neonatal and > 55 years or immuno-suppressed especially malignancy

Antibiotics of choice;

IV Ampicillin/Amoxicillin

Ceftriaxone no value as intrinsically resistant

54
Q

Tuberculous mengitis;

_________ in elderly

High index of suspicion for ______

Often __-______ ill health

Previous __ on ___

Poor yield from ___

High ______ if not treated

_________ + ________ key (add ______+_______)

A

Tuberculous mengitis;

reactivation in elderly

High index of suspicion for diagnosis

Often non-specific ill health

Previous TB on CXR

Poor yield from CSF

High morbidity if not treated

Isoniazid + Ridampicin key (add pyrazinamide + ethambutol)

55
Q

Cryptococcal meningitis;

______

Mainly in ____ disease

CD4<___

_______ infection

Subtle _______ presentation

_____ picture on CSF

Serum and CSF cryptococcal ______

IV _______ B/_______

_____le

A

Cryptococcal meningitis;

Fungal

Mainly in HIV disease

CD4<100

Disseminated infection

Subtle neurological presentation

Aseptic picture on CSF

Serum and CSF cryptococcal antigen

IV amphotericin B/flucytosine

fluconazole

56
Q

Patient presents with suspected meningitis (and no signs of shock or severe sepsis)

Which Bloods should be done?

A
  • blood cultures
  • FBC, urea, creatinine, electrolytes, LFTs, clotting screen
  • Procalcitonin (CRP if unavailbale)
  • Meningococcal and pneumococcal PCR
  • serology sample
  • glucose
57
Q

Patient presents with suspected meningitis and septicaemia

Which Bloods should be done?

A

blood cultures

FBC, urea, creatinine, electrolytes, LFTs, clotting screen

Procalcitonin (CRP if unavailbale)

Meningococcal and pneumococcal PCR

serology sample

glucose

58
Q

Patient presents with suspected meningitis and septicaemia

Which tests should be done?

A

bloods

throat swab for bacterial culture

59
Q

Patient presents with suspected meningitis and no signs of shock or severe sepsis

Which tests should be done?

A

bloods

throat swab

CSF

Further tests

60
Q

Patient presents with suspected meningitis and no signs of shock or severe sepsis

Which CSF testing should be done?

A
  • opening pressure
  • microscopy, culture and sensitivity
  • meningococcal and pneumococcal PCR
  • protein
  • glucose
  • lactate
61
Q

Patient presents with suspected meningitis and no signs of shock or severe sepsis

Which further tests should be done if no aetiology on first panel?

A

If bacterial meningitis seems likely ;

16S rRNA PCR on CSF

If viral meningitis seems likely ;

CSF PCR for: HSV 1, HSV 2, VZV and enterovirus

Stool for enterovirus PCR

throat swab for enterovirus PCR

62
Q

CSF pleocytosis is not _______ ______

A

CSF pleocytosis is not bacterial meningitis

63
Q

CSF interpretation

Tube 1. _______: ___ ____. differential

Tube 2. _______: g__ _____, c_____

Tube 2. _____: ______, _____
Tube 4: H______: C___ ______, _______

A

CSF interpretation

Tube 1. haematology: cell count. differential

Tube 2. Microbiology: gram stain, cultures

Tube 2. Chemistry: glucose, protein
Tube 4: Haematology: cell count, differential

64
Q

__-__% of bacterial meningitides are _____ negative

A

10-15% of bacterial meningitides are culture negative

65
Q

Which viruses suggest a patient is immunocompromised?

A
  • EBV
  • CMV
  • HHV -6/7
  • T. Gonfii
  • JC virus
66
Q

What are the typical CSF findings in acute viral meningitis?

Cells:

Gram stain for bacteria:

Bacterial antigen detection:

Protein g/l (normal 0.1-0.4):

Glucose mmol/l (normal 2.3-4.5):

A

Cells: 101-103 (lymphocytes)

Gram stain for bacteria: negative

Bacterial antigen detection: negative

Protein g/l (normal 0.1-0.4): normal or slightly high

Glucose mmol/l (normal 2.3-4.5): usually normal

67
Q

What are the typical CSF findings in acute bacterial meningitis?

Cells:

Gram stain for bacteria:

Bacterial antigen detection:

Protein g/l (normal 0.1-0.4):

Glucose mmol/l (normal 2.3-4.5):

A

Cells: 101-104 (predominantly polymorphs)

Gram stain for bacteria: positive

Bacterial antigen detection: positive

Protein g/l (normal 0.1-0.4): high

Glucose mmol/l (normal 2.3-4.5): less than 70% of blood glucose

68
Q

What are the typical CSF findings in acute tuberculous meningitis?

Cells:

Gram stain for bacteria:

Bacterial antigen detection:

Protein g/l (normal 0.1-0.4):

Glucose mmol/l (normal 2.3-4.5):

A

Cells: 101-103

Gram stain for bacteria: positive or negative

Bacterial antigen detection: negative

Protein g/l (normal 0.1-0.4): high or very high

Glucose mmol/l (normal 2.3-4.5): less than 60% of blood glucose

69
Q

In partially treated bacterial meningitis __________ may predominate but the protein is often ___

A

In partially treated bacterial meningitis lymphocytes may predominate but the protein is often high

70
Q

CSF is 99% predictive of bacterial meningitis if;

WBC count > ____

Neutrophils > ____

Protein > ___ mg/dl

Glucose < __ mg/dl

Glucose CSF/serum < ____

A

CSF is 99% predictive of bacterial meningitis if;

WBC count > 2,000

Neutrophils > 1180

Protein > 220 mg/dl

Glucose < 34 mg/dl

Glucose CSF/serum < 0.23

71
Q

What are the other non-infectious causes of neutrophillic pleocytosis & low csf glucose?

A
  • Chemical-meningitis (contrast)
  • Bechet syndrome
  • Drug induced (NSAIDs, sulfa, INH, IVIG, OKT3)
72
Q

What is aseptic meningitis?

A

Term used to mean non-pyogenic bacterial meningitis

73
Q

Aseptic meningitis describes a spinal fluid sample that typically has;

a __ number of WBC

a ______ _______ protein

A normal ______

A

Aseptic meningitis describes a spinal fluid sample that typically has;

a low number of WBC

a minimally elevated protein

A normal glucose

74
Q

What are the treatable infectious causes of aseptic meningitis/encephalitis syndrome?

A
  • HSV 1 & 2
  • Syphilis
  • Listeria (occasionally)
  • Tuberculosis
  • Ctyptococcus
  • Leptospirosis
  • Cerebral malaria
  • african tick typhus
  • lyme disease
75
Q

What are the treatable non-infectious causes of aseptic meningitis?

A
  • carcinomatous
  • sarcoidosis
  • vasculitis
  • dural venous sinus thrombosis
  • migraine
  • drugs
    • co-trimoxazole
    • IVIG
    • NSAIDs
76
Q

What are the indications for hospital admission in acute adult bacterial meningitis?

A
  • signs of meningeal irritation
  • impaired conscious level
  • a petechial rash
  • febrile or unwell and have had a recent fit
  • any illness, especially headache and and close contacts of patients with meningococcal infection- even if they have had prophylaxis
77
Q

Providing a patient’s (with acute adult bacterial meningitis) airway, breathing and circulation do not require immediate attention what should be done on arrival in hospital?

A
  • blood culture for coagulation screen
  • give the treatment as outlined in ‘initial therapy before pathogens are identified’ vide infra, and immediately thereafter
  • take a throat swab which should be plated as soon as practicable by the microbiologist
  • disrupt and swab or aspirate any petechial or pupuric skin lesions for microscopy and culture
78
Q

who should undergo CT prior to LP?

A
  • immunocompromised state: HIV/AIDS, immunosuppressants, after transplantation
  • History of CNS disease: mass lesion, stroke or focal infection
  • New onset seizure: within 1 week of presentaiton
  • Papilloedema: presence of venous pulsations suggests absence of high ICP
  • Abnormal level of consciousness
  • Focal neurological deficit: dilated nonreactive pupil, abnormalities of ocular motility, abnormal visual fields, gaze palsy, arm or leg drife
79
Q

What are the warning signs in meningitis?

A
  • marked depressed conscious level (GCS <12) or a fluctuating conscious level (fall in GCS >2)
  • Focal neurology
  • seizure before or at presentation
  • shock
  • bradycardia and hypertension
  • papilloedema
80
Q

What patients should and should not be given steroids in bacterial meningitis

A

ALL patients (10mg iv 15-20 min before or with first dose of antibiotic and then every 6 hours for 4d)

NOT; post-surgical meningitis, severe immunocompromise, meningococcal or septic shock or those hypersensitive to steroids

81
Q

What are the key interventions in managing bacterial meningitis with low GCS or fluctuating GCS?

A
  • admit to highly supervised clinical area; do baseline investigations
  • secure airway and high flow O2
  • IV 2G ceftriaxone stat [+/- amoxicillin if >55 to cover listeria]
  • IV corticosteroids
  • DO NOT wait for CT/LP
82
Q

What are the contact prophylaxis regimens?

A
  • ​600mg rifampicin orally 12-hourly for four doses (adults and children over 12 years)
  • 10ml/kg rifampicin orally 12-hourly for four doses (ages 3-11 months) (IV).

specific warnings about reduced efficacy of oral contraceptives, red colouration of urine and staining of contact lenses should be given

OR

  • 500mg ciprofloxacin orally as a single dose for adults and children aged more than 12 years (not licensensed for this purpose but has been extensively used in school and community outbreaks). use of ciproflocaxin in younger adults is not recommended

OR

  • 250mg ceftriaxone intramuscularly as a single dose in adults
  • 125mg IV ceftriaxone as a single dose in children under 12 years.
    *
83
Q

What vaccines are available?

A
  • neisseria meningitidis
    • serogroups A and C (W135 & Y) - commonly used in travel vaccination
    • group C conjugate vaccine
  • haemophilus influenzae (HiB vaccine)
  • Streptococcus pneumoniae
    • pneumococcal vaccines- polysaccharide and conjugate

Neurology (41 decks)

Brainscape helps you reach your goals faster, through stronger study habits.
© 2024 Bold Learning Solutions. Terms and Conditions