Brain_FCs_Infections Flashcards
Strep pneumoniae meningitis commonly ass’d w/ what 3 things?
- Pneumonia
- Sinusitis
- Otitis
Meningitis ass’d w/ overwhelming sepsis, purpura fulminans (gun metal grey lesions)
Neisseria meningitidis
Chemoprophylaxis in what types of meningitis? What drugs to use?
- Neisseria meningitidis (Rifampin, ceftriaxone, or ciprofloxacin)
- H. influenzae if succeptible child <4 yrs. (Rifampin)
Neonatal meningitis - most common cause
Group B Streptococcus
Meningitis in elderly w/ chronic disease (diabetes, cirrhosis, alcoholism, renal failure)
Group B Streptococcus
Type of vaccine for Haemophilus influenzae?
Protein Conjugated Hib vaccine
H. influenzae meningitis may be ass’d w/ what 2 things?
sinusitis or otitis
GI tract organism, not nasopharyngeal carriage
Listeria monocytogenes
Meningitis in newborns, immunodeficient, or elderly
Listeria monocytogenes (or Group B Streptococcus)
Meningitis ass’d w/ pregnancy loss
Listeria monocytogenes
When to think meningitis might be Staphylococcus aureus?
Post-Neurosurgery or Endocarditis
When to think meningitis might be Gram negative bacilli (Salmonella)?
Newborns & Post-Neurosurgery
Meningitis primary management/diagnosis
- Draw blood cultures & give antibiotics (1st dose)
- CT scan
- Lumbar Puncture
Empiric antibiotic therapy for acute bacterial meningitis when age >2mo.
Ceftriaxone + Vancomycin
(+ Dexamethasone)
If >50 yrs, add Ampicillin (Listeria)
Adult Tx along w/ antibiotics to reduce unfavorable outcomes?
Dexamethasone
Most common viral meningitis
Enterovirus
HSV Encephalitis treatment?
Acyclovir
Vaccine preventable form of meningitis that may follow parotitis
Mumps
Meningitis ass’d w/ Facial Palsy &/or Peripheral Neuropathy
Lyme disease (aseptic)
2 spirochetal ASEPTIC meningitis causes?
Treponema pallidum (Syphilis) & Borrelia burgdorferi (Lyme)
Granulomatous meningitis - 3 causes?
Mycobacterium tuberculosis, Cryptococcus neoformans, Coccidioidomycosis
Encephalitis CSF usually looks like ______ meningitis
aseptic
Major treatable cause of encephalitis?
HSV (HSV 1»_space; HSV 2, except in newborns)
Encephalitis acquired from maternal genital lesion during birth –> HSV 1 or HSV 2?
HSV 2
Arbovirus that kills some bird hosts (crows)?
West Nile Virus (WNV)
Encephalitis w/ highest morbidity/mortality?
Eastern Equine Encephalitis (but it’s rare)
2 common presentations of rabies?
- Most common - Hydrophobia (fear of swallowing water – painful pharyngeal spasms)
- Flaccid paralysis
Viral encephalitis that is also cause of infectious mononucleosis
EBV
Viral encephalitis ass’d w/ VZV reactivation
Herpes zoster
Viral encephalitis following monkey bites
Herpes B virus
Focal encephalitis, particularly of temporal lobe
HSV
Demyelinating process (white matter lesions) in immunocompromised hosts - destroys connections
Progressive Multifocal Leukoencephalopathy (JC virus)
kuru “falling sickness” among New Guinea Highlanders
Subacute spongiform encephalopathies (caused by prions)
Other names:
- Creutzfeld-Jacob Disease (CJD)
- “Mad Cow Disease”
Startle reactions, ataxia, dementia, w/:
- Normal CSF
- Long incubation period
Diagnosis?
Mad cow disease (CJD, Subacute spongiform encephalopathy)
Back/radicular pain w/ fever & weakness, then paralysis
Spinal Epidural Abscess
Parameningeal brain abscess from hematogenous spread in person w/ alpha-hemolytic strep & R–>L shunt
Staph aureus
Parameningeal brain abscess from direct introduction (open head trauma or neurosurgery)?
Staphylococci, gram-negative bacteria
Acyclovir is active against ___ & ____, not ____
HSV & VZV, not CMV
Acyclovir requires?
Thymidine Kinase (TK) phosphorylation to make monophosphate
Symptom management for edema w/ increased ICP?
Corticosteroids (tighten BBB, but also decrease penetration of chemo agents)
Headache symptom management for brain tumors?
Corticosteroids
Primary spinal cord tumors –> 2 most common types?
Ependymoma or Astrocytoma
Primary spinal cord tumor Tx?
Resection
- XRT (sometimes)
Spinal meningiomas –> where in spinal cord?
Thoracic spine (most)
4 common symptoms of spinal meningioma
Paraparesis
- Radicular pain
- Hyperreflexia
- Sphincter dysfunction
Metastatic spinal tumors usually go to vertebral bodies how?
via bloodstream (then compress spine via epidural space)
Difference in pain from spinal tumor vs. disc disease
Spinal tumor - worse lying down
Disc disease- better lying down
Diagnosis? –> back pain & neuro deficit w/ history of cancer
Spinal cord compression (tumor)
3 most common primary tumors to metastasize to spine?
Prostate, breast, lung
Paraneoplastic syndrome –> most common type of cause?
Immunologic factors – Antibody or t-cell responses agains nervous system antigens expressed by tumor
Paraneoplastic syndromes- most common in pts w/ what 2 types of tumors?
Small cell carcinoma of the lung
- Thymoma
Type of headache specific to jaw claudication?
Ominous Tempora Arteritis
Type of headache w/ drop attacks
Colloid cyst, 3rd ventricle
Type of headache w/ intracranial HYPOtension
Orthostatic
Type of headache: Acute, w/ Horner’s Syndrome
Carotid artery dissection
Type of headache: Cough, w/ exertion
Arnold-Chiari syndrome
Type of headache: periodic w/ autonomic features (3 types)
Cluster, Paroxysmal hemicrania, Trigeminal cephalgias
Type of headache: orgasmic (3 types)
Pre-coital, Intra-coital, Post-coital
Contraindications of Triptans (5HT agonists) in headache Tx?
Pregnancy
- Complicated migraine
- Hypertension or CAD/PVD
- Renal or Hepatic insufficiency
4 drugs established as effective Prophylaxis for benign headaches?
Valproate & Topiramate
- Propranolol (long-acting)
- Frovatriptan
Prophylaxis for benign headache & mood stabilization?
Valproate
Prophylaxis for benign headache & weight loss?
Topiramate
Prophylaxis for benign headache & hypertension?
Propranolol
Prophylaxis for menstrual-associated migraine?
Frovatriptan
Prophylaxis for benign headache & insomnia?
Tricyclic, amitriptyline
Prophylaxis for benign headache & anxiety?
SNRI, venlafaxine
Type of headache in overweight girls w/ papilledema, elevated ICP, & visual problems (may lead to blindness)?
Ominous “Pseudotumor” cerebri
Cause of primary CNS lymphoma in AIDS?
Epstein-Barr virus (genomes in transformed B cells)
Example of 2 Grade IV tumors?
Glioblastoma, Medulloblastoma
2 types of “sheath” tumors?
Meningioma & Schwannoma (others are Neuroepithelial)
Pilocytic astrocytoma - circumscribed or infiltrative? Tx?
Circumscribed
Tx = Surgical resection
Tumor w/ increased cellularity & pleomorphic cells, but NO mitoses, microvascular proliferation, or necrosis
Diffuse astrocytoma
Tumor that stains w/ densely cellular small “blue cells”
Medulloblastoma
Typical spread of medulloblastoma?
via CSF to bone or regional lymph nodes
- tumor in cerebellar vermis has spread via CSF to 4th ventricle
Tumor w/ benign spindle cells on histology?
Schwannoma
Tumor w/ perivascular organization of tumor cells?
Primary CNS lymphoma (EBV)
Most common (3) primary sites of metastatic CNS tumors
- Lung
- Breast
- Other (skin, colon, kidney)
Most common(3) locations of metastasis to the CNS?
- Brain parenchyma (cerebral hemisphere then cerebellum)
- Dura mater
- Leptomeninges
Common location of epidural hemmorrhage?
Temporal-parietal region (where skull fractures cross path of & lacerate Middle Meningeal Artery)
Clinical consequence of epidural hemorrhage
- High pressure arterial bleeding (rapid expansion & mass effect on brain)
- Rapid loss of consciousness (eventual herniation if not treated)
Contusion vs. concussion (difference)?
Contusion: parenchymal injury caused by direct transmission of kinetic energy through skull to brain (soft tissue bruise)
Concussion: Clinical syndrome characterized by “immediate & transient alteration in brain function (including alteration of mental status & level of consciousness) resulting from mechanical force or trauma
Location of most shear injuries?
- Frontal & temporal lobes
- Corpus Callosum
2 types of shear injuries?
Sheared vessels –> Hemorrhage
Sheared axons –> Traumatic Axonal Injury
4 common locations of Traumatic Axonal Injury?
- Corpus callosum
- Cerebral white matter
- Internal Capsule
- Rostral brainstem
Staining method to identify axonal swellings in TAI?
Amyloid Precursor Protein (looks brown on Silver stain biopsy)
Why does glioblastoma multiforme cause contrast enhancement on CT scan?
Abnormal vascular permeability
Structure that produces CSF? Location?
Choroid plexus
- Walls of lateral ventricles
- Roof of 3rd & 4th ventricles
Do capillary endothelial cells in Choroid Plexus have fenestrations?
Yes
(epithelium of CP provides BBB, whereas brain capillary endothelium provides BBB elsewhere)
General location of most vasogenic edema?
Mainly white matter
Composition of vasogenic edema?
Plasma filtrate & protein
ECF volume in vasogenic edema?
Increased
Active demyelination causes ____ edema
vasogenic
Organizing hematomas cause ____ edema
vasogenic
Abscesses cause ____ edema
vasogenic
Pathogenesis of cytotoxic edema?
Cellular swelling due to impaired membrane ion pump systems
General location of most cytotoxic edema?
Gray & white matter
Composition of cytotoxic edema?
Intracellular H2O & Na+
ECF volume in cytotoxic edema?
Decreased
Infarction of brain tissue causes ____ edema
cytotoxic
Acute hypoxic-ischemic encephalopathy causes _____ edema
cytotoxic
Loss of gray-white matter demarcation occurs in _____ edema
cytotoxic
2 histologic features of cytotoxic edema / acute cerebral infarct?
- Red neurons
- Vacuoles
Pathogenesis of Interstitial (hydrostatic) edema
Increased brain fluid due to impaired CSF circulation or resorption
General location of interstitial (hydrostatic) edema?
Periventricular white matter
Composition of interstitial edema
Same as CSF
ECF volume in interstitial edema
Increased
Hydrocephalus causes _____ edema
interstitial
Colloid cyst blocking outflow of CSF causes _____ edema
interstitial
Primary & secondary events of Subfalcian herniation
- Sliding of cingulate gyrus beneath falx cerebri
- Compression of ACA – Infarction of medial frontal lobe
Primary & secondary events (4) of Transtentorial herniation
- Displacement of medial temporal lobe through tentorial notch
- a. Stretching & compression of 3rd CN (ipsilateral CN paresis & pupillary dilatation)
b. Compression of contralateral cerebral peduncle (Kernohan’s notch), causing ipsilateral hemiparesis (same side as primary lesion)
c. Compression of PCA, causing infarction of medial temporal-occipital lobes
d. Shearing of perforating vessels in upper brainstem–> Duret hemorrhages in midbrain & rostral pons & Coma (damage to RF)
Primary & secondary events of Cerebellar tonsillar herniation
- Downward displacement of cerebellar tonsils through foramen magnum
- Compression of medulla –> dysfunction of respiratory & cardiovascular control centers –> cessation of respiration & death
Gross pathology of global hypoxic ischemia due to increased ICP
Softening, edema, poor gray-white demarcation
Biochemical pathology of TAI
Shear injury damages axonal membranes –> Influx of Ca++ & Na+ through membrane channels –> Axonal swelling –> Axonal cytoskeletal damage –> Impaired axonal transport –> Accumulation of axonal transport proteins
How does choroid plexus form/secrete CSF?
Active transport of ions across its epithelium from blood to CSF
How does Glioblastoma cause edema & what type of edema is it?
- Angiogenesis forms abnormal blood vessels don’t have functional BBB
- Vasogenic edema
How does MS cause edema & what type of edema is it?
- Cytokine mediated inflammation causes “leaky” vessels
- Vasogenic edema
Amyloid precursor protein on Silver staining means what?
Traumatic Axonal Injury
Cause of Meningitis? –> Gram-negative (pink), pleomorphic coccobacilli (diplococci)
Haemophilus influenzae
Meningitis ass’d w/ pregnancy loss
Listeria monocytogenes