Bacterial and Fungal meningitis Flashcards
بسم الله الرحمن الرحيم
وكفي بالله وليا وكفي بالله نصيرا
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S.aglactiae is one of the group ,,,,,, hemolytic streproccoi
Catalas ….. gram ……cocci
Virulence factor is ?
B BETA
catalse - gram +
Virulence factor ?
Polysaccaride capsule
Pathogenisis of diseases of S,aglactae?
It is commensal inermittenr in the vagina of some famels
Acuired by neonates from bith canal casuing :
Nenotatl sepsis
Neontalal menigits
Neonatal Pnemonia
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Predisponsig factors for streptococci infections in neonates?
P2rolonged
Prolonged labor >18 h
Premature labour
Ruptured membreane
Fever at time of labour
Laboratory diagnosis of the S,aglaticae
Samples from CSF and blood
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direct smear gram + cocci in chains
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Cultured in blood agar
B hemolytic complete hemolysis
Special tests for S.aglactiae ?
CAMP test with staphs
Hippurate hydrolysis test
CAMP test show
Special for S.aglagtiace
there is al ine of staphs then you put a prepdndicular line of the suspected organism
if S.alagticae an arrow of hemolysis formed towardsd the line of staphs
Hppurate hydolysis test
Special for s,aglactiae
Hydolsing hippurate converting its color into violet
How to prevent s.aglatiae infections
Screening women pregnant at 35-37 weeks for S.agalctiae by doing vaginal and Rectal cultures if + Pencillin G must be adminsterd at time of deleviery
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Women with Prorlonged labor and premature labor and fever during labor and invasice GBS s.aglacitae befors must also be given Pencillin G
Mention diseases caused by listera monocyogens
Spesis and meningitsi in new born , pregannt women , immunocomprised adults
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Febrile gastroenterirtis
Imp propertis of listeria :
Shor non spore forming gram …..bacilli
In ,,,,,,,And,,,,and,,,,and,,,, trasmitted to humans by contat with,,,,,,,,or theri ,,,,,
Human listrosis is cassued by ,,,,,,,as ,,,,,,,,,,,,,,,(,,,,,,orl,,,,,,,)
an unsual Tumbiling movment at ,,,, not,,,,
gram + bacilli
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Git of animals , plants . water and soil
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animals and theri feces
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listera monocytogens as zoontoic ( sproadic or small epidemic)
22 NOT 37
Type of movement of listera monocyotgens and at which temp appera?
Tumbling movment
at 22 not 37
Both streptococci and listrea casue b ehmolysis how to differentiate ?
by catalase !
Listera of narrow b hemolysis is catalase +
while Streptococci of wide beta hemolysis of catalase -
Cold enhcnement mean in listeria ?
Can relicate in refergated food
The most imp virulence factor for listeria ?
Facultative intracellular parasite
can live inside?
Epithelial
Macrohpages
parenchymal cells
Modes of transmisson of listeria monocytogene
=By unpastuirized milk ,raw meat and vegetables
=Neonate through Tansplacental or During labour
=Contact with domestsic farm animals and their feces
it is food borne dieseas\
Describe pathogenisis of listeria
It colonized in colon and then to Female genital tract from which can invade neonate transplacental if membranes ruptured or during birth
during birth the neonate acquire meningitis and the pathogen reach meninges through blood stream .
It depends on ? The ability to invade and facultative intraculluar survival
Mention virulence factor of listeria
-Facultative intracellular parasite !
Hemolysin (listerolysin O)
making it able to escape from vacuoles of phagmosomes and contiues repulicating insde cytoplasm of the cell.
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C/P of nenontal disease
Early onset disease if tranplacental may cause granulomatous infantiseptica That leads to abscess + granulomas in multiple organ then death
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late onset during leaving birth canal
may cause Meningitis or menigio encephalitis with speis 2-3 weeks
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addition : in immmunocomprised and elderly
Meningits endocarditis speis
Mention one of the leading causes of bacteral meningits in patients with cancer and renal transplants recepients ?
Listeria monocytogens
Listeria is
=intacelluar gram …. rods that occur singlt or in pairs resembling……..
=MOtiel tumbling movment to be differentiated from ,,,,,,
=small grey colonies iwth narrow zone of B hemolysis on blood agar so differentiaed from streptococci by ?
Gram + Diptheriodis
coynebactria
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Catalse test
Prevention of listeria
no immunization
limiting the eposure of pregnants to
Animals
unpasturized milk
raw meat and vegetables
Cryptococcal meningitis is caued by ?
Cryptococcus neformans
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Espeically in AIDS patients
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IT IS divded into 5 serological types ABCD AD according to ? capsular antigen
Mode of transmisson
Inhalation of the organism from the soil contaitng bird droppings no human to human transmission
Pathogenisis of cryptococcal menigits
The inhhlation of the cryptococcus neforamns leading to its phagocytosis in lungs being asymptomatic or Causing Lobar pnemonia then hematogenous spread to the CNS and meiniges Causing menigitis
The ability to produce melanin aids it to evade phagocytic killing
