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Flashcards in Fever and headache Deck (16):

Pathogenic causes of meningitis: viral; bacterial; fungi; protozoa; other

Viral: Common, enteroviruses, influenza, HSV2
Bacterial: N. meningitidis, strep pneumoniae. RARE: haemophilus infulenzae; mycobacterium tuberculosis; listeria monocytogenes
Fungi: rare, AIDS in cancer. Cryptococcus neoformans
Protozoa: rare, angiostrongylus cantonensis. Pacific. eosiniophilic
other: drugs, trauma, neurosurgery, cancer


Meningeal inflammation and symptoms

Headache; photophobia; neck stifffness, drowsiness
Systemic response: fever, drowsiness, septic shock; rash (neisseria)



What is bacterial meningitis preceded by

Nasopharyngeal colonisation by N. meningitidis


How to diagnose meningitis

CSF; blood cultures; throat swab; blood to detect bacterial DNA by PCR


Kernig's sign

Flex the hip and extend the knee. + when there is pain in doing so. Indicates meningitis or subarachnoid haemorrhage

Not due to hamstring stretch, makes headache worse. Stretching cauda equina

Not tell tale


CSF findings for viral and bacterial meningitis

L4/5, cauda equina

glucose: normal; protein (Ig): high/normal; WBC: high; cells: lymphocytes; gram stain: -ve; culture:-
Bacterial: glucose: low (bacteria and neutrophils respiring); protein: high; WBC: high; cells: neutrophils; gram stain: +/-: culture: ++/-


Meningitis and rash. If no rash what do you do?

Meningococcal meningitis! Petechiae, Neisseria

No rash: all effort to find aetiology, to exclude meningococcal disease. If CSF gram -:
Antigen test strep pneumoniae; CSF PCR (amplifies nucleic acid sequences to be seen, uses primers) for causes; blood PCR; throat swab


Streptococcal antigen test

CSF, urine or blood put on a card
If strep. pneumoniae antigens present, will move on blotting paper. Antibodies react with antigen and colour change



____ displaced, specific ____ to DNA form organisms added.Cooled down to ____ the ____..
____ back up to allow___ _____ to lengthen the strands.
Visualised with a _____ tag added. Will ____ every time new strands are made

Strands displaced, specific primers to DNA form organisms added.Cooled down to anneal the primers..
Heat back up to allow DNA polymerase to lengthen then strands.
Visualised with a fluorescent tag added. Will double every time new strands are made


Meningitis epidemiology

5% death rate
Most common in winter
Most common in very young
Maori pacific children common


How does neisseria meningitidis evade complement

Gram __ ___. Often ____, spheres Stain with ___ and red
Thick polysaccharide ___ to stop _____ and ___ formation
Protein that binds human ___ _, which ____ regulates complement
___ that bind ___, preventing C3 from breaking
___ similar to blood group antigens so ignored. (Level of LPS determines ____ of disease/ symptoms), releases ___ into blood stream

Gram - coccus. Often diplocci, spheres Stain with saffron and red
Thick polysaccharide capsule to stop opsonisation and MAC formation
Protein that binds human factor H, which down regulates complement
Pilli that bind C4, preventing C3 from breaking
LPS similar to blood group antigens so ignored. (Level of LPS determines extent of disease/ symptoms), releases extra into blood stream


Neutrophil traps and septic shock charcateristics

When ____/ bacterial load is very ____, neutrophils release ____ into capillaries.
____ these, ____ and traps ____, RBC's and platelets.
Due to ____, reduces _____ flow and ____, causing ____.
Shock: low __, ____, reduced ____ ____= organ failure

When LPS/ bacterial load is very high, neutrophils release DNA into capillaries.
Clogs these, sticky and traps bacteria, RBC's and platelets. Platelets cause
Due to blockage, reduces blood flow and oxygen, causing shock.
Shock: lowBP, tachycardia, reduced organ perfusion= organ failure


Bacterial meningitis treatment

If in progress, dexamethasone before penicllin?? at hosp
IV antibiotics (penicillin)
blood cultures
transfer to hosp
pain relief, fluids, IV antibiotics
Droplet precautions


Viral meningitis treatment

Analgesia and rest


Drugs and uses; meningitis

-Are similar to penicillin derived from acremonium
-cefalozin/cephalexin: oral for pneumonia
-ceftriaxone: pneumonia, uti,GIT, bacterial meningitis (not in Auckland)


Septic shock management broadly

IV fluid/oxygen to maintain organ function
Antibiotics/surgery to resolve infection cause

emergency scenario with 10-15% mortality and after organ failure 40-50%