Nervous System Flashcards
Pleocytosis
increase in cell count in the CSF (inflam. cells)
Treatment of nervous system infections
Broad spectrum antibiotics that can penetrate the BBB
Higher doses needed to maintain adequate concentrations in the CNS
Are Bacteriostatic or bactericidal drugs preferred?
Bactericidal
Diagnosis
CSF examination
bacterial infections in the nervous system can appear as
meningitis, encephalitis, encephalomyelitis
Histophilus somni causes
Thromboembolic meningoencephalitis (TEME) or Thrombotic meningoencephalitis (TME)
1-2 weeks after pneumonia
blindness, ataxia, convulsions, depression, coma
death in 12 hours
What is the pathognomonic lesion of histophilus somni
multiple reddish necrotic foci, thrombi in blood vessel composed of leukocytes, fibrin, bacteria
pathogenesis of histophilus somni
bacteria adhere to endothelial cells -> vasculitis, thrombosis (replicate), infarction –> inflam. response
Apoptosis of endothelial cells
Host inflam. b/c of endotoxin and activation of coagulation cascade
polymorphonuclear leukocytes and macrophages to inf. site
Listeria monocytogenes host
cattle, sheep, goats
Listeria monocytogenes disease
Circling Disease- ingestion of contaminated silage during winter
Encephalitis- most common presentation in ruminants
Septicemic listeriosis- calves, die
L. monocytogenes pathogenesis
bacteria invade oral mucosa, through trigeminal nerve to brain stem
unilateral signs of trigeminal and facial paralysis
What sample would you send to the lab for L. monocytogenes
brain stem
Diagnosis for L. monocytogenes
listeria enrichment culture or PCR
L. monocytogenes treatment
susceptible to penicillin (drug of choice)
high doses required to achieve minimal bactericidal concentrations in brain
Chlamydia pecorum
sporadic bovine encephalomyelitis in feedlot cattle
