Neuro Block 3 Flashcards
clostridia
gram positive
spore forming
anaerobes
rods
clostridia tetani
in soil/feces
penetrate wounds and release toxin (tetanospasmin)
spastic paralysis
generalized - most common in US, 3-21 days, muscle rigidity, supportive care (benzos, respirator), give tetanus immune globulin. give tD booster
clostridia botulinum
classic - ingested from canned foods, flaccid paralysis, cook is usually victim, CNS not affected, die from respiratory paralysis, 12-48 hours, antitoxin then supportive care
infants - feed honey, non fatal, infection, constipation/respiratory distress
protozoa
usually ingest cyst
lumen dwelling and blood tissue
naegleria
warm brakish and fresh water
have flagella
Primary Amebic Meningoencephalitis (PAM) - fatal, CNS infection (eat away), CSF cloudy w increased proteins, increased neutrophils, increased pressure, decreased glucose, treat with amphotericin B
acanthamoeba
freshwater and soil
cyst double refraction
granulamtous amebic encephalitis (necrotizing cerebellum, midbrain, brainstem)
develops slowly and leads to confusion, dizziness, hallucinations
keratitis - opaque cornea, usually from rinsing eyes with tap water, treat with intraconeuzole and narcotics for pain
toxoplasma gondii
toxoplasmosis
immunocompromised affected
in outdoor cats feces/tissue cysts in meats
can cross placenta
ring enhancing lesions on CT (AIDS)
infants get hydrocephaly then fluid is absorbed and have microcephaly
tx - pyrimethamine and sulfadiazine
trypanosomes
east African sickness - acute
west african sickness - chronic
from tsese flies
cervical lymphedemopathy
Herpes viridae
exposed by close body contact
goes latent (ganglia for HSV)
no humoral or cell mediated immunity prevent latency
HSV
90% of adults exposed
stomatisis - cold sores
virus replicates at initial site then moves to ganglia, heals without scarring
can get reactivation
treat with acyclovir
ocular herpes
dendritic branching ulcers
HSV1 encephalitis
most common cause of encephalitis in adults
red blood cells in csf
cytomegalovirus
almost all people have it
in US adults get exposed with sexual contact
#1 congenital infection - not affected mother (seronegative) gets exposed in first or second trimester leading to fetal hearing loss and retardation, has owls eye inclusions
tx - gangcyclovir
rhabdovirus
rabies
single stranded negative RNA
in rabid animals and you must be bitten
14-90 days
neurotrophic
negri bodies
post exposure prophylaxis 5 ml rabies antitoxin
can use rabies immune globulin as well
bacterial meningitis
infection, pus (neutrophils) in subarachnoid space
can result in communicating hydrocephalus
cortical vessels engorged and can thrombose
can spread to brain (cerebritis) and ventricals
CSF - high WBC (neutrophils), high protein, low glucose
bacteria - depends on age, S. pneumoniae and N. meningitidis common in children and adults
viral meningitis (aseptic)
mostly viral (enterovirus often)
CSF - high WBC (lymphocytes), moderately elevated protein, normal glucose
focal lesions
abscess in brain
liquefacive necrosis surrounding by granulation tissue and fibrotic rim
edema and possible herniation, seizure focus
often streptococci and staphylococci
CSF - increased pressure, high WBC, normal glucaose
TB
thick exudate in subarachnoid space
granulomatous
worse at base of brain
CSF - moderate WBC, high protein, glucose normal
neurosyphilis
meningovascular - chronic meningitis, cerebral gummas
paretic - spirochetes within brain, dementia
tabes dorsalis - immunologic injury to dorsal root ganglia, degeneration of posterior columns
viral encephalitis
microglial nodules, intracellular inclusions, perivascular cuffing by lymphocytes
arbo virus - arthropod vectors, can cause necrosis and be fatal
herpes - HSV 1 involves temporal and inferior frontal lobes/inflammation/necrosis/neurons with intracellular inclusions, HSV 2 neonatla/extensive necrosis
varicella zoster
latent in ganglia following chickenpox
vesicular eruptions in dermatomal distribution
cytomegalovirus
can cause congenital malformations
affects immunocompromised, large intracellular inclusions, can involve ependymal and paraventricular areas
rabies
via bites and contact with infected animals
retrograde transport in peripheral nerves, slow
encephalitis, negri bodies
spasms of throat, difficulty swallowing, aspiration of fluids (hydrophobia)
fungal
often in inmmunocompromised
cryptococcal - meningitis follows perivascular spaces into brain, prominent cysts in oraganisms in basal ganglia
aspergillus - invades and occludes vessels, causes hemorrhagic infarcts