CASE 3 - HEADACHE Flashcards
The 2 dural layers are bound together except for when they form…?
- Septae (e.g. falx cerebri, falx cerebelli)
- Dural venous sinuses
Meningitis occurs in which 2 layers of the meninges?
Arachnoid mater & pia mater (the leptomeninges)
What is meningitis?
Inflammation of the meninges in the brain or spinal cord (defined by an abnormal number of white cells in the CSF)
What is the classic triad of meningitis?
- Headache/change in mental status
- Fever
- Neck stiffness
If all three are ABSENT, it is very UNLIKELY to be meningitis. 95% of patients have AT LEAST 2/4 symptoms.
Name the 3 common causes of VIRAL meningitis
- Enteroviruses (coxsackie B)
- Herpes simplex virus
- VZV reactivation (in adults)
Name the 2 most common causes of BACTERIAL meningitis
- Neisseria meningitidis
- Streptococcus pneumoniae (most common)
(note that the causative agent varies amongst different age groups)
Compare the severity of bacterial vs. viral meningitis
Viral meningitis is typically far less severe and resolves on its own.
Bacterial meningitis is generally fatal if left untreated.
Which bacteria is now less commonly implicated in meningitis due to widespread vaccination?
Haemophilus influenzae type B
Listeria monocytogenes is more commonly found in which patient populations?
- Elderly
- Immunocompromised (e.g. diabetes)
- Heavy alcohol use
Name 3 pathways of meningitis infection (and give examples)
- COLONISATION of nasopharynx or upper airways before entering the CNS:
- Contiguous spread of infections from ENT
- DIRECT INNOCULATION:
- Surgery
- Trauma
- HAEMATOGENOUS
- Endocarditis
- Osteomyelitis
- Skin sepsis
Name 5 clinical features of meningitis (other than the classic triad)
- Photophobia
- NV
- Seizures
- Cranial nerve palsies
- Malaise
Name 3 clinical features which are more specific to neisseria meningitidis infection
- Myalgia & petechial/purpuric rash (esp. children)
- Waterhouse-Friderichsen syndrome
What is Waterhouse-Friderichsen syndrome?
A group of symptoms most often associated with meningococcal septicaemia.
Characterised by DIC and hemorrhagic necrosis of the adrenal glands, causing adrenal insufficiency.
Use the SNNOOP10 pneumonic to list the headache ‘red flags’
S - systemic symptoms including fever
N - neoplasm history
N - neurological deficits (including altered state of consciousness)
O - onset is sudden/severe (e.g. thunderclap headache)
O - older age (>50 years)
P - papilloedema
P - positional headache
P - progressive headache
P - precipitated by sneezing, coughing, or exercise
P - pregnancy or puerperium
P - pattern change from previous headache/new headache
P - painful eye with autonomic features
P - post-traumatic onset of headache
P - pathology of the immune system (e.g. HIV)
P - painkiller/analgesic overuse
Outline the difference between a primary vs. secondary headache
PRIMARY = pain/headache due to the headache itself
SECONDARY = headache due to another pathology / underlying condition
Take a headache history
- PLOTRADIO
- Other symptoms:
- no. of headaches per month, aura, change in vision, recent trauma, response to previous treatment, past medical history
https://www-uptodate-com.proxy.library.adelaide.edu.au/contents/evaluation-of-headache-in-adults?search=headache&source=search_result&selectedTitle=1~150&usage_type=default&display_rank=1#H7
Outline the physical examination that should be performed in someone with a headache (especially if a secondary cause is suggested) and why each component is important.
- SIGNS OF TRAUMA: haematoma
- PALPATION: of the pericranial muscles (tenderness suggests tension-type headache)
- PALPATION: of the temporal artery + test jaw movements (temporal arteritis or TMJ dysfunction)
- PALPATION: along the trigeminal nerve (trigeminal neuralgia)
- PALPATION: of the sinuses (sinusitis)
- EYE EXAMINATION / EXTRA-OCULAR MOVEMENTS: tenderness or difficulty suggests raised ICP
- FUNDOSCOPY: papilloedema
- CERVICAL SPINE MOBILITY: nuchal rigidity suggests meningitis
Use the acronym ‘POUND’ to describe the typical characteristics of a migraine headache. Name any additional symptoms not covered by this acronym.
P - pulsatile O - one-day duration (but up to 72 hours) U - unilateral N - nausea/vomiting D - disabling intensity
Additional symptoms: aura, photophobia, exacerbated by exercise
https://www.amboss.com/us/knowledge/Headache/
Describe the character, course, and additional symptoms of TENSION headaches
CHARACTER: bilateral, dull, pain in a ‘band-like’ pattern around the forehead
COURSE: initially episodic, but can become chronic and daily
ADDITIONAL SYMPTOMS: possibly photophobia and phonophobia, NOT exacerbated by exertion
Describe the character, course, and additional symptoms of CLUSTER headaches
CHARACTER: unilateral (characteristically around the eye), stabbing, piercing, burning, SUDDEN excruciating onset
COURSE: clustering attacks lasting for weeks followed by a period of remission (~75% of cases). Typically occur at night and last <1 hour.
ADDITIONAL SYMPTOMS: rhinorrhoea, lacrimation, sweating, flushing, Horner’s syndrome
Which type of PRIMARY headache tends to last a few hours - days?
Migraine
Which types of PRIMARY headaches are typically unilateral?
Migraine
Cluster
Which type of PRIMARY headache exhibits NO autonomic symptoms?
Tension headache
Which type of PRIMARY headache is most at risk for medication-overuse headaches?
When is the headache WORST?
Migraines
Morning: when drug levels are lowest
Which type of PRIMARY headache is NOT exacerbated by exercise?
Tension headache
Which type of PRIMARY headache can cause multiple ‘attacks’ in one day?
Cluster headache
Which type of PRIMARY headache most often occurs at night?
Cluster headache
Describe the ‘PIN’ acronym (ID migraine) to screen for migraine.
During the last 3 months, has the patient had:
P - photophobia. Did lights bother you a lot more?
I - incapacitate. Did the headache limit your ability to work or do other daily activities for at least one day?
N - nausea. Did you feel sick to your stomach?
A migraine prodrome typically occurs in the 24-48 hours before the headache. Name 4 features of this prodrome.
- Excessive yawning
- Sudden hunger or lack of appetite
- Mood changes
- Difficulties reading or writing
What might trigger a hormonal headache in women?
OCP
Menstruation / changes in hormone levels
May present as a migraine
Which foods can trigger migraines?
Tyramine-containing foods
e.g. red wine, chocolate, strong aged cheeses, cured meats, citrus fruits, fermented or pickled foods
Describe a typical migraine aura
VISUAL, SENSORY, and/or SPEECH disturbances:
VISUAL (MOST COMMON): scintillating or central scotoma, flashing lights, distorted colours, photophobia
SENSORY: paresthesia
SPEECH: aphasia
They develop gradually and last ~60 minutes
https://www.youtube.com/watch?v=lcdtw93A3Zs
What is meant by ‘positive’ and ‘negative’ aura symptoms?
POSITIVE = flashing lights, spots, lines, pins & needles etc.
NEGATIVE = blurry vision, numbness
Which headache is associated with trigeminal neuralgia?
Cluster headache
Frequency of headaches/epidemiology
PRIMARY: tension-type (70%), migraine (15%), others including cluster headache (0.1%)
SECONDARY: systemic infection (63%), head injury (4%), vascular disorders including SAH and temporal arteritis (<2%), brain tumour (0.1%)
Name 4 medications that can cause headaches
note that headache is a very common side effect of medications
Amlodipine Isosorbide mononitrate Codeine Sertraline Sumatriptan
Name a headache classification tool
ICHD-3
International Classification of Headache Disorders (3rd edition)
https://ichd-3.org
What is Kernig’s sign?
A sign of meningeal irritation - place the patient in a supine position, flex the thigh at the hip, and extend the knee.
Positive if knee extension causes pain + resistance.
(only positive in severe meningitis)
How does amlodipine cause headaches?
Vasodilatory effects
Outline the pharmacological approach to migraine management
- Start with non-opioid analgesic (e.g. aspirin, ibuprofen) + anti-emetics
- Triptans if needed
- Migraine prophylaxis (e.g. amitriptyline)
Outline the non-pharmacological approach to migraine management
- Cold packs over the forehead or back of the skull (targeting the supraorbital and greater occipital nerves)
- Hot packs over the neck and shoulders (targeting the innervation of the scalp)
- Neck stretches and self-mobilisation
- Rest in a quiet dark room.
Screening for causes of fever
- Coughs, colds, respiratory infections
- Dysuria
- Cuts/wounds
- Immunocompromised (e.g. diabetes)
Sepsis vs. septic shock
SEPSIS = spectrum of disease with mortality ranging from moderate to severe, depending on many factors
SEPTIC SHOCK = a subset of sepsis with significantly increased mortality due to severe abnormalities of circulation and/or cellular metabolism
Acute bacterial meningitis produces a ________-rich infiltrate in the subarachnoid space.
Acute bacterial meningitis produces a NEUTROPHIL-rich infiltrate in the subarachnoid space.
Extension of inflammatory exudate from the subarachnoid space into the brain causes …
CEREBRITIS
How does meningitis cause raised ICP?
- Interstitial oedema (due to obstruction of CSF outflow)
- Cytotoxic oedema (release of toxins from bacteria and neutrophils)
- Vasogenic oedema (increased BBB permeability)
What is aseptic meningitis? (give some examples)
Inflammation of the meninges, but bacterial culprit cannot be identified
e.g. viral meningitis, slow-growing organisms, partially-treated meningitis
What is it called when there is inflammation of both the meninges AND brain?
Meningoencephalitis
What usually causes CHRONIC meningitis?
Fungi
What is the normal range for intracranial pressure?
4 - 18mmHg
6-25cm H2O
How is meningitis diagnosed?
Lumbar puncture + CSF analysis
What is Brudzinski’s sign?
Patient lies supine –> neck flexed
If neck flexion causes their knees to automatically bend, it is indicative of meningeal irritation
What investigation should be performed BEFORE a lumbar puncture if raised ICP is suspected?
CT head should be performed first if raised ICP is suspected
Name 3 signs of meningeal irritation
- Neck stiffness/nuchal rigidity
- Kernig’s sign
- Brudzinski’s sign
(but these are quite insensitive and only present in very severe cases)
Name 3 systemic signs of inflammation that may be present in someone with meningitis
- Fever
- Hypotension
- Tachycardia
Name one sign that may indicate raised ICP in someone who has meningitis
Papilloedema (<5% of cases)
Name 3 manifestations of underlying infections that could have caused meningitis
- Otitis media: bulging, red tympanic membrane
- Petechiae or nonblanching rash: meningococcal meningitis
- Maculopapular rash: viral meningitis
Name 4 features suggestive of meningitis that has spread to the brain parenchyma (meningoencephalitis)
- Focal neurological signs (e.g. paresis, aphasia, extrapyramidal symptoms)
- Seizures
- Behaviour change, psychosis
- Altered consciousness
Name 6 contraindications for lumbar puncture (BASICS)
B - bleeding diathesis
A - anticoagulant therapy
S - suspected DIC
I - infection (localised, e.g. epidural abscess)
C - chiari malformation
S - significant cardiorespiratory compromise that may further deteriorate with positioning for lumbar puncture
When should treatment for bacterial meningitis be initiated?
Diagnostic and treatment steps should be initiated SIMULTANEOUSLY.
Empiric treatment should not be delayed for diagnostic steps (ideally administer antibiotics within 60 minutes)
Do not delay empiric antibiotic therapy in patients suspected of having bacterial meningitis!!!
Name the investigations that should be sought & procedures that should be performed in someone with suspected bacterial meningitis
- IV access + obtain blood cultures
- Empirical antibiotics (+ steroids if needed)
- IF LP CONTRAINDICATED: perform head CT
- IF LP NOT CONTRAINDICATED: perform LP
- CSF analysis
https: //www.amboss.com/us/knowledge/Meningitis/
How many sets of blood cultures should be obtained before starting empiric antibiotics for bacterial meningitis?
At least 2 sets of blood cultures
What are the red flags that indicate IMAGING must be performed before LUMBAR PUNCTURE (FAILS - 7 components)
F - focal neurological deficitis
A - altered mental status (GCS <14) AND age >60
I - ICP (raised) AND immunocompromised
L - lesion (space-occupying)
S - seizures AND stroke (history of CNS disease)
Name 5 routine LABORATORY studies for meningitis and state their importance
- 2-3 BLOOD CULTURES (prior to Abx)
- CBC - raised WBC count (or lowered when SEVERE)
- BMP - blood glucose needed to analyse CSF glucose. Can find mild electrolyte disturbances and signs of AKI if severe.
- CRP - elevated CRP has good negative predictive value for bacterial meningitis.
- COAGULATION STUDIES - bleeding diathesis contraindicates LP
CSF analysis in BACTERIAL meningitis
APPEARANCE
CELL COUNT & DIFFERENTIAL
OPENING PRESSURE
LACTATE
PROTEIN
GLUCOSE
GRAM STAIN
APPEARANCE: cloudy
CELL COUNT & DIFFERENTIAL: leukocyte count >1000 with >80% granulocytes
OPENING PRESSURE: markedly raised
LACTATE: markedly raised
PROTEIN: raised
GLUCOSE: decreased
GRAM STAIN: positive gram stain and culture
CSF analysis in VIRAL meningitis
APPEARANCE
CELL COUNT & DIFFERENTIAL
OPENING PRESSURE
LACTATE
PROTEIN
GLUCOSE
GRAM STAIN
APPEARANCE: clear
CELL COUNT & DIFFERENTIAL: leukocyte count >10-500, raised lymphocytes
OPENING PRESSURE: normal or slightly raised
LACTATE: variable
PROTEIN: normal or slightly raised
GLUCOSE: normal
GRAM STAIN: no organisms present
In which patient group are white cell counts less elevated during bacterial meningitis?
Children
What is hydrocephalus?
Blockage of CSF drainage
Name 4 causes of a headache + fever
- Infection (e.g. meningitis, encephalitis, abscess)
- Haemorrhage (e.g. SAH, stroke)
- Autoimmune
- Drug-related (e.g. serotonin syndrome)
Why are corticosteroids administered alongside empiric antibiotics?
Prevents injury to the leptomeninges (due to inflammation) as the antibiotics destroy the bacteria
A lactate level above 3.5mmol/L indicates which type of meningitis?
Bacterial
What are the advantages of using PCR for blood and CSF samples?
- Faster result
- Less affected by prior use of antibiotics
- Can identify difficult-to-culture organisms (e.g. viruses)
What are the advantages of using CULTURING over. PCR?
- Only culturing will give susceptibility results
- Culture can detect pathogens that aren’t in the PCR test
(but the two are complimentary)
Similarities and differences between SAH and meningitis on HISTORY
Both can have signs of meningism, photophobia, phonophobia, headache, and fever.
SAH: ‘thunderclap’ headache, sentinel headache in the weeks prior, sudden LOC, RFs for SAH (e.g. HTN, smoking), exertion (sex, exercise)
MENINGITIS: vaccination Hx, recent infections (e.g. sinusitis, otitis media)
https://emedicine.medscape.com/article/1164341-clinical#b1
Compare the prognosis of meningitis caused by HSV-1 + VZV infections VS. HSV-2
HSV-1 & VZV: fulminant, more likely to cause encephalitis and present with symptoms of parenchymal involvement
HSV-2: common cause of recurrent meningitis, being & self-limiting. Patient may give history of genital ulcers
Describe the abnormal results that can be seen on CT scan and CSF analysis of someone with a SAH
CT: blood in subarachnoid space
CSF: yellowish (xanthocromia) or red discolouration, elevated RBCs
What is xanthocromia and when does it typically occur in CSF after an SAH?
Xanthocromia is a yellowish tinge caused by the presence of bilirubin in the CSF, secondary to RBC breakdown
It occurs in nearly 100% of patients 12 hours after an SAH (but as early as 2-4 hours)
A CT scan is useful for identifying ______ of raised ICP, but NOT useful for identifying whether the ICP IS ________.
A CT scan is useful for identifying CAUSES of raised ICP, but NOT useful for identifying whether the ICP IS RAISED.
How can you tell whether there has been a traumatic tap in LP?
- Decreasing concentration of RBCs in serial tubes
- Rapid coagulation
- Absence of xanthocromia
State the organism that is indicated by the following Gram stain results from a CSF analysis:
- Gram-positive diplococci
- Gram-negative diplococci
- Small pleomorphic Gram-negative Coccobacilli
- Gram-positive cocci or Coccobacilli
- Gram-positive Rods and Coccobacilli
- Gram-positive diplococci: S. pneumonia
- Gram-negative diplococci: N. meningitidis
- Small pleomorphic Gram-negative Coccobacilli: Haemophilus Influenza
- Gram-positive cocci or Coccobacilli: Group B strep
- Gram-positive Rods and Coccobacilli: L Monocytogenes
What is the Monroe-Kellie Doctrine?
The sum of volumes of brain + CSF + intracranial blood is constant.
An increase in one should cause a decrease in one or both of the remaining two.
What is the formula for cerebral perfusion pressure (CPP)?
CPP= MAP - ICP
Name 3 complications of meningitis
- Sensorineural hearing loss (transient or permanent)
- Focal neurological deficits
- Seizures
- Cognitive impairment
- Communicating hydrocephalus
What is the pathophysiology between Waterhouse-Friedrichsen syndrome?
Coagulopathy triggered by endotoxins –> haemorrhagic necrosis of the adrenal glands
Describe the pathophysiology behind DIC
Excessive clotting stimulated by something entering the blood. The increased clotting depletes the platelets and clotting factors needed to control bleeding, causing excessive bleeding.
Can develop SUDDENLY: usually then causes bleeding.
Can develop SLOWLY: clot formation (e.g. DVTs, PE). Often due to cancer.
Compare decorticate and decerebrate posturing (clinical manifestation and underlying pathology)
DECORTICATE: ‘flexor’ posturing –> bilateral FLEXION of upper extremities and EXTENSION of lower extremities. Injury is PROXIMAL to the brainstem.
DECEREBRATE: ‘extensor’ posturing –> bilateral EXTENSION of the upper extremities and FLEXION of the lower extremities. Injury is DISTAL to the brainstem or pons. Worse prognosis.
(in deCORticate posturing, the arms are flexed towards the CORE of the body)
Why is DECEREBRATE posturing indicative of worse prognosis?
Decerebrate posturing occurs when there has been damage at the lower part of the brainstem, where autonomic functions are controlled –> lower chance of survival.
Which medications are the most common culprits for medication overuse headache?
Opioids
Triptans
First-line for migraine prophylaxis?
Depends on the ADVERSE EFFECTS + PATIENT COMORBIDITIES (and other drugs they’re taking)
Amitriptyline
Candesartan
Propranolol
IIH
.
Why are painful eye movements a feature of meningeal irritation?
Occurs when inflammation affects the meninges or optic nerves
Abducens is the longest nerve. Covered by the meningeal sheath. Most likely to be affected
Why are there higher opening pressures in bacterial meningitis?
CSF flow is impaired due to inflamed meninges.
CSF not absorbed and doesn’t flow as it should.
In which patient group does meningitis present abnormally?
Presentation is usually nonspecific in infants and young children
Key points of the physical exam in meningitis detection
- Evidence of systemic illness / sepsis
- ENT & respiratory exam
- Rashes (not necessarily present)
- Full neuro exam (impairment in cognitive function & focal neurological signs suggest involvement of brain parenchyma)
What is the most common cause of FUNGAL meningitis?
Cryptococcus gatti
Why is ceftriaxone the antibiotic of choice for empiric treatment?
Covers N. meningitidis and S. pneumoniae (the 2 most common causes)
Benzylpenicillin is used against which causes of meningitis?
L. monocytogenes
What is MIC? What is it used for?
Minimum inhibitory concentration (MIC).
The lowest concentration of an antimicrobial drug that will inhibit growth of a microorganism after overnight incubation.
Triptan counselling
- Most effective before the headache (during the aura phase)
- Cannot use an ergotamine within 24 hours of a triptan (due to adverse effects and drug reactions)
- If patients are also on SSRIs or SNRIs they must be counselled on serotonin toxicity
When should migraine prophylaxis be considered?
2 or more migraines a month
Give an example of how a patient’s co-morbidities can influence the choice of migraine prophylaxis
Co-morbidity: INSOMNIA; give TCA, pregabalin, gabapentin
Co-morbidity: ANXIETY; give propranolol
Co-morbidity: DEPRESSION; SSRI, SNRI, TCA
Co-morbidity: OBESITY, DIABETES; candesartan
Describe the pathophysiology and clinical features of a SAH sentinel headache
Sentinel headache can occur in the weeks leading up to a SAH. It is likely due to a low-grade leakage in the SAH leading to thrombus formation.
Symptoms:
- Sudden, severe headache
- Transient diplopia
Describe the appearance of papilloedema on fundoscopy
- Blurring of the optic margins
- Venous engorgement
- Loss of venous pulsations
- Optic disc elevation
MIGRAINE MANAGEMENT:
Non-opioid analgesics should not be used for more than __ days per month.
Triptans should not be used for more than __ days per month.
Non-opioid analgesics should not be used for more than 15 days per month.
Triptans should not be used for more than 10 days per month.
Outline the empirical pharmacological treatment for suspected bacterial meningitis
- IV Ceftriaxone OR cefotaxime
- IV Dexamethasone 10mg
https: //tgldcdp-tg-org-au.proxy.library.adelaide.edu.au/viewTopic?topicfile=meningitis&guidelineName=Antibiotic&topicNavigation=navigateTopic#toc_d1e764
Which type of meningitis can cause a petechial / non-blanching rash?
Bacterial
Which type of meningitis can cause a maculopapular rash?
Viral
The Gram stain of a CSF sample from a patient suspected to have bacterial meningitis shows Gram-positive diplococci. Which organism is likely to be present?
S. pneumoniae
The Gram stain of a CSF sample from a patient suspected to have bacterial meningitis shows Gram-positive diplococci. Which organism is likely to be present?
S. pneumoniae
The Gram stain of a CSF sample from a patient suspected to have bacterial meningitis shows Gram-NEGATIVE diplococci. Which organism is likely to be present?
Neisseria meningitidis
Outline the following details for a lumbar puncture:
- Intervertebral space selected for needle
- Reason for selecting this space
- How this intervertebral space is clinically identified
- The meningeal layer(s) penetrated to reach the CSF space
- Name of CSF space for sampling
- Intervertebral space selected for needle: L4
- Reason for selecting this space: termination of the spinal cord; less chance of damaging nerves
- How this intervertebral space is clinically identified: iliac crest
- The meningeal layer(s) penetrated to reach the CSF space: dura mater, arachnoid mater
- Name of CSF space for sampling: subarachnoid space
3 Hx questions to look for SAH
Was the headache maximal at onset?
Did it occur during physical exertion?
Have you had a similar headache (maybe with double vision) in the past few days or weeks? (sentinel headache)
Subarachnoid haemorrhages are often caused by Berry aneurysms. What are 2 focal neurological deficits that could result from this?
CN II lesion: bitemporal hemianopia
CN III lesion: ‘down and out gaze’ with ptosis
