Flashcards in Diseases Test 2 Deck (13):
Infection of the sub-arachnoid space.
Symptoms: headache, fever, NUCHAL RIGIDITY, and altered mental ability.
Causes: Viral (most common) - enteroviruses/picornovirus, Bacterial (life-threatening) - Streptococcus pneumonia, Neisseria meningitidis, and Haemophilus influenza type b, protozoa and fungal (immuno-compromised)
Different pathogens affect different age groups (see lectures)
Virulence factors like capsules allow pathogens to evade immune system
Vaccines available against several strains of life-threatening bacteria.
Treatment: H&P, blood culture, empiric treatment, neuroimaging, LP/biopsy, identify organism, finally switch to definitive therapy. Must start therapy ASAP for bacterial meningitis.
Infx of parenchyma
Symptoms: fever, headache, and alteration of mental status, motor and sensory deficits (not seen in meningitis), progression to seizures, speech disturbances, lethargy, and coma.
Causative agents: Viral - Enterovirus, Arbovirus, Herpes Virus, Rabies
Bacterial - Rickettsia, Mycoplasma, Acute disseminated encephalomyelitis (ADEM)
Symptoms: Fever, headache, neurolgic effects
Mechanism of disease: pre-existing ischemia, necrosis begins as cerebritis and then becomes encapsulated.
Causative agent: Streptococci (most common), Pseudomonas, Haemophilus, Staphylococcus, Bacteroides,
Mycobacterium, fungi, or parasites (immunocompromised)
Can rupture and cause meningitis
Diffuse cerebral dysfunction without inflammation usually due to toxin or metabolic dysfunction
Aseptic Meningitis Syndrome
Misnomer often viral but could be noninfectious.
Symptoms: fever, headache, and photophobia. Less neck stiffness and altered mental status. Incidence highest during first year of life.
Lab values: CSF increase in lymphocytes and monocytes, slight increase in protein, and normal glucose
Treatment: supportive therapy
Symptoms: 30 min to one week in length. Pressing/tightening. Mild to moderate in intensity (not debilitating). Bilateral (think headband distribution). Not aggravated by physical activity. No nausea or vomiting. Some photo/phono phobia.
Mechanism of disease: Muscle contraction causing greater occiptal nerve compression. Exacerbated by emotional stress.
Epidemiology: women > men (possibly sampling bias). Onset < 40 years old. Episodic if < 180/year; Chronic if < 180/year. Increased prevalence with increased educational attainment.
Treatment: Often self-treated, Analgesics (ibu, asa, tyenol), acupuncture, biofeedback, relaxation technique
Symptoms: Severe, unilateral, orbital, supraorbital, or temporal pain lasting 15-180 minutes. Circadian periodocity. Every other day to every 8th day. AUTONOMIC SYMPTOMS: lacrimation, nasal congestion, rhinorrhea, forehead sweating, miosis, ptosis, eyelid edema, conjunctival injection.
Epidemiology: Male:female 4:1. Mean onset age 27-31. Incidence 2.5/100,000/year. Prevalence: 1/1000
Mechanism: Incompletely understood. Hypothalamic activation of trigeminovascular autonomic system and parasympathetics.
Treatment: OXYGEN. Triptans too, and prophylaxis for episodic clusters.
Symptoms: Intermittent, unilateral, throbbing, crescendo-decrescendo headache lasting hours to days. Gradual onset, associated with nausea; family history. Aura +/-
Epidemiology: Female:male = 3:1. Onset < 40. Prevalence 18% women and 6% men. Lifetime prevalence 20-25%. >50% people with migraines miss > 2 days a work/month.
Pathophysiology: Uncertain. Linked to low seratonin levels followed by seratonin spike and vasoconstriction which is followed by disease causing vasodilation.
Treatments: Attacks = Triptans, Dihydroegotamine (DHE), Percholoperazine, metoclopramide, Tyenol, ibu, naproxen, dexamethasone (Triptan and DHE most emphasized)
Prophylaxis: AMITRYPTALINE, divalproex sodium/socium valproate, propanolol, timolol.
Contraindications: With Aura avoid OCPs! Viagra?
Primary Measles Encephalitis (PME)
Pathophysiology: virus invades and replicates within brain cells. Typically at the same time of rash presentation.
Epidemiology: 1-3 of 1,000 patients.
Treatment - supportive therapy
Morbidity/Mortalitiy: 10-15% mortality rate. Of those that survive, 25% experience lifelong neuro problems.
Measles induced Acute Disseminated Encephalomyelitis (APME)
Results in demyelination. Can be seen with a recent history of measles infx.
Epidemiology: 1 in 1000 measles infx.
Measles Subacute Sclerosing Panencephalitis (SSPE)
Children who contact measles before the age of two are at the greatest risk. Symptom free for 6 to 15 years post acute infx and survive 1 to 3 years after symptoms develop.
Epidemiology: 4 to 11 per 100,000 cases.
Rare often fatal syndrome that is correlated with aspirin use in children in the presence of a viral infection (VZV etc.) Causes liver and brain damage.