Exam 1 Meningitis- Prunuske Flashcards
What are clinical symptoms of meningitis?
Fever and headache; Less commonly: nuchal rigidity (stiff neck), photophobia, rash (Gram- Bacteria), upper respiratory symptoms, anorexia, nausea, vomiting, diarrhea, altered mental state
What is the source of most meningitis?
Through blood, CSF and trauma to the cranium
Give an overview for the management of meningitis
History and physical, blood culture (start empiric treatment), Neuroimaging of altered mental state, papilladema, Lumbar puncture- ID organism, switch to definitive treatment
What are routine tests to run on a sample of CSF?
WBC w/ differential, RBC count, glucose, protein, gram stain, bacterial culture
What are the findings of CSF of a bacterial meningitis?
Increased pressure, Increased WBC count, more PMNs, Increased protein, decreased glucose
What are findings of a viral meningitis in CSF sample?
increased WBC, increased lymphocytes and monocytes, slight increase in prtn, normal glucose
What is a big difference between aseptic and normal meningitis in terms of symptoms?
Aseptic does not have neck stiffness and altered mental state
When is the most common time to have aseptic meningitis?
highest during first year of life.
What is the treatment for viral meningitis?
supportive therapy and recover on their own, can be fatal in neonatal period
What are most viral meningitis caused by?
Enterovirus (RNA viruses), less commonly: HSV2, arthropod-borne viruses, HIV
What are the 2 common enteroviruses?
Coxsackie and ECHO virus
What is the genome organization of enteroviruses (coxsackie and ECHO)
ssRNA + sense, naked (non-enveloped)
What are most common symptoms of septic meningitis?
Fever, stiff neck, irritability and neurological dysfunction (cranial nerve dysfunction), acute onset and progression
What are the main bacterial causes of septic meningitis?
S. pneumoniae (pneumococcal), Neisseria meningitidis (meningococcal), Haemophilus influenza type B
What is the first empiric treatment of septic meningitis? When should you start it?
Ceftriaxone of cefotaxime. IMMEDIATELY
What are other agents and their treatments that some patients may be at risk of causing meningitis?
MRSA (vancomysin), HSV-2 (acyclovir), Listeria (ampicillin)
What is the mechanism of cetriaxone (3rd gen cephalosporin)
Binds to penicillin binding proteins (transpeptidases) to inhibits cell wall synthesis. Broad, can be inactivated by beta-lactamases
What is the most common cause of meningitis in under 2 mo old
Group B strep
What is the most common cause of meningitis in 11-17 year olds?
N. meningitidis
What is the most common cause of meningitis in adults?
S. pneumoniae
List steps of development of bacterial meningitis
1)Mucosal colonization of nasopharynx 2)invasion and multiplication in blood stream 3)/4) cross into CSF, 5) release of inflammatory cytokines in CSF by astrocytes and microglia 6) Increased permeability of BBB, 7) Diapedesis of leukocytes into CSF, 8) edema and increased intracranial pressure, 9) neuronal injury including hearing loss (Cranial nerve 8)
What are the virulence factors of Neisseria meningitidis?
Capsule, IgA protease, Pili, endotoxin, outer membrane proteins
What are the virulence factors of Haemophilus influenzae?
Capsule, IgA protease, Pili, endotoxin, outer membrane proteins
What are the virulence factors of Streptococcus pneumoniae?
Capsule, IgA protease
Is listeria gram- or gram+?
Gram+
What does LPS cause when an Gram- organism infects an individual?
a rash that does not fade with pressure