Gram stain Flashcards
gram pos cocci
staph auresus- if n/surg or trauma last month add vanc
strep pneumo- vanc and ceftriaxone
gram neg cocci
neisseria- 3rd gen ceph
neisseria gonorrhoea
moraxella catarrhalis
gram pos bacilli
listeria - amp or penicillin G
ABCDL actinomycetes bacillus anthraxis, cereus clostridium diphtheria listeria
Gram neg bacilli
enterobacteraceae (klebsiella or E coli)- ceftr
pseudomonas or acinetobacter - if neurosurg last months then ceftazidime, cefepime, meropenem
Hydatid cyst vs amoebic abscess on exam
hydatid large liver asymptomatic, non tender no fever
abscess large tender liver, fever
Gram positive cocci in clusters UTI
staph saprophyticus
enterococcus look like
gram pos cocci in chains
In the lab how do they figure out staph vs strep
staph catalase positive
strep catalase neg
No haemolysis on blood agar
enterococcus
partial = green = alpha = s pneumo (optochonin sens) and s viridans (optochonin resist) complete = clear = beta = s pyogenes, s agalactiae
What are the coag neg staph?
s saprophyticus
s epidermis
Kaposis - cause
HHV8
nocardia is
gram positive
filamentous
olecranon bursitis
staph
Q fever
coxiella burnetti
pleomorphic
gram neg
bacilli or coccobacilli
obligate intracellular
risk factors for mucormycosis
iron overload
diabetes
once have it hihg risk for cavernous sinus thrombosis (CN III, IV, V1, V2, VI initial signs)
give amphotericin B then posaconazole
when would you think fusarium?
neutropaenic and blood cultures grow hyaline mould
endopthalmitis
angio invasive- stroke like events
lesions near toenails
drowning event, think which fungus
scedosporium
MOA penicillin vs ceftaroline
ceftaroline binds PBP2
penicillin inhibits formation of peptidoglcan cross links n the bacterial cell wall by binding to enzyme DD-transpeptidase–>cannot catalyse the formation of cross links –>imbalance between cell wall production and degradation
What in MRSA enables the necrotising lung abscess formation?
PVL gene in MRSA
Community vs healthcare acuired MRSA
HA: large SCCmecA, MDR, infection many sites like blood, lung skin, diabetes/dialysis/long term health care
CA: small SCCmecA, younger patients, healthy, MSM, IVDU , skin and soft tissue infection, often express PVL which allows to form lung abscesses, can be sens to bactrim, macrolide, doxy, lincosamides
Why VRE?
overuse of third gen cephalosporins
Difference between AMPC beta lactamases and ESBL
ESBL is inhibited by clavulanic acid
AMPC beta lactamases are not
Monocytes in CSF?
listeria monocytogenes
commonest viral men
enterovirus then HSV 2 then varicella
