REVISION EXTRAS Flashcards
what 3 things can cause meningitis?
infection, adverse reaction to meds and autoimmune diseases
what microorganisms usually cause acute meningitis and which cause chronic?
bacteria and viral usually cause acute
fungi cause chronic
whats examples of viruses that can cause meningitis?
herpes simplex virus
HIV
enteroviruses e.g. coxsackie
what are enteroviruses?
a genus of positive-sense single-stranded RNA viruses that enter hosts through the intestine
what are the 3 main symptoms of meningitis?
nuchal rigidity
headache
fever
what findings would you expect to see in a lumbar puncture on a patient with meningitis?
elevated opening pressure
WCC >5 per microlitre
glucose concentration less than 2/3rds of blood glucose concentration
protein >50mg/dL
why do we see elevated protein levels in the CSF in meningitis?
inflammation leads to a more permeable blood brain barrier so protein leaks into the subarachnoid space from the blood, resulting in markedly increased CSF protein levels.
what are the main bacterial causes of meningitis in newborns?
group B strep, E. coli, and less commonly, Listeria monocytogenes
what are the main bacterial causes of meningitis in children and teens?
Neisseria meningitis and streptococcus pneumoniae
what are the main bacterial causes of meningitis in adults?
streptococcus pneumoniae and listeria monocytogenes
what is powassan?
a rare tick-borne disease caused by a virus that causes meningoencephalitis
other than bacteria, virus and fungi… what other causative organisms can cause meningitis?
ticks
tuberculosis
parasite
what parasite can cause meningitis?
p. falciparum
which fungi can cause meningitis?
candida
cryptococcus
what are the 3 types of horizontal gene transmission?
conjugation
transduction
transformation
what is conjugation in horizontal gene transfer?
pilli attaches 2 bacteria and the plasmid containing the resistant gene can be replicated and passed on via direct contact
what is transduction in horizontal gene transfer?
DNA is transmitted from one cell to another via a bacteriophage
what is transformation in horizontal gene transfer?
extracellular naked DNA from bacterial lysis is taken up by cells that have developed genetic competence
what produces CSF?
ependymal cells in the choroid plexus
outline the movement of CSF?
secreted into the lateral ventricles
moves through interventricular foramen into the 3rd ventricle
moves through the cerebral aqueduct into the fourth ventricle
flows out the 2 lateral and 1 medial aperture to fill the subarachnoid space
where is CSF reabsorbed?
arachnoid granulations and into the dural venous sinuses
what are the functions of the choroid plexus?
synthesis of CSF
blood brain barrier
what are the functions of the CSF?
removal of waste proucts
shock absorbance
nourishes brain tissue
what are the most common causes of bacterial pneumonia?
streptococcus pneumonia
haemophilus influenzae
staph aureus
what are some uncommon bacteria that cause atypical pneumonia?
mycoplasma, legionella and chlamydia
which microorganism is lobar pneumonia mostly associated with?
streptococcus pneumoniae
what viruses are common for pneumoniae?
influenza
respiratory syncytial virus - mostly children
what are the different types of pneumonia
lobar broncho atypical/interstitial aspiration community acquired nosocomial
what are some complications of pneumonia?
sepsis
lung abscess
acute respiratory distress syndrome
respiratory failure
