Bacteriology Flashcards
causative organism of cat scratch disease
bartonella spp
gram negative bacilli
causative organism of cellulitis/osteomyelitis caused by animal bite
pasteurella multocida
disease transmitted by aerosols of cattle/sheep or amniotic fluid
Q fever –> coxiella burnetii
causative organism of Q fever
coxiella burnetii
causative organism of rocky mountain spotted fever
ricketssia rickettsi
source of transmission for rocky mountain spotted fever
ricketssia ricketssi –> dog tick (dermacentor)
vector responsible for transmission of chagas disease
reduviid bug
tabes dorsalis from tertiary syphyllis occurs due to damage to what spinal tract
dorsal column
what type of pupil may be found in tertiary syphyllis
argyl robinson pupil
treatment in nocardia vs actinomyces
‘treatment is a SNAP’
sulphonamides (co trim) - nocardia
actinomyces - penicillin
difference in nocardia vs actinomyces presentations
nocardia causes pulmonary infections in immunocompromised patients, cutaneous infections after trauma which can spread to CNS = abscesses
actinomyces causes oral/facial abscesses that drain through sinus/tract, often associated with dental trauma. can also cause PID with IUD’s
what do langhans giant cells in TB represent
secondary infection
salmon coloured truncal rash (rose spots), initial constipation then diarrhoea, abdominal pain, bradycardia, fever, progression to GI haemorrhage and ulceration
typhoid fever (salmonella typhi)
what can cause false positive results on non-treponemal specific testing for syphillis
pregnancy
viral infections (e.g. EBV, hepatitis)
drugs (chlorpromazine, procanamide)
rheumatic fever
lupus (anti-cardiolipin Ab) nd leprosy
testing available for syphillis
serological tests;
non-treponema specific - VDRL, RPR
treponema specific - FTA-ABS, TP-PA
direct testing;
- darkfield microscopy
- PCR
after treating syphillis will antiodies still be present on serological testing
Non-treponema tests will become negative, treponema tests will remain positive
Ab wont be present on non-treponema tests i.e. VDRL and RPR
Ab will still be present on treponema specific tests i.e. FTA-ABS, TP-PA
presentation of rickettsia typhus
rash starts centrally then spreads outwards sparing the hands and feet (unlike rickettsia rickettsi - spotty mountain fever)
rickettsial organisms and vector for typhus
endemic - fleas, rickettsia typhi
epidemic- human body louse, rickettsia prowazekii
common cause of culture negative endocarditis
coxiella burnettis - Q fever
vector for Q fever
no vector
flu like symptoms, headache, cough, pneumonia, hepatitis
Q fever
comma or S shaped organism, grows at 42 degrees, causes diarrhoea
campylobacter
bloody diarrhoea, liver abscess
E. histolytica
day care outbreaks, pseduoappendicitis
Y enterocolitica
causative organism - painful genital ulcer may bleed and inguinal lymphadenopathy
chancroid - haemophillus ducreyi
causative organism - painless beefy red ulcer that bleeds readily on contact
granuloma inguinale = klebsiella
what UTI causing organism shows ‘swarming’ on agar due to motility
proteus
plasmodium falciparum on blood smear
trophozoite ring within RBC and crescent shaped gametocytes
what condition may bring about a false negative PPD result
PPD positive in past or current TB infection
PPD = no TB infection
or false negative in immunocompromised patients (esp low CD4 counts)
virulence factor h. influenzae
virulent capsule
virulence factor e. coli
type 3 secretion system, haemolysins and fimbrae
during what stage of chlamydia cell cycle does it become infectious
extracellular elementary body
gram positive spore forming anaerobe
c.diff
shigella invades immune system via what cells
microfold cells
virulence factor for TB
activates macrophages and induces release of TNF alpha
major glycolipid in bacterial cell wall called cord factor
virulence factor of h. influenza and strep pneumoniae
cleavage of IgA
contracted from southwestern USA. Fever, night sweats, arthralgia, cough, erythema nodosum or multiforme
coccidiodomycosis immitis
disease which causes migratory arthritis after GAB infection and mechanism of infection
rheumatic fever
antibody cross reactivity against foreign and host immune systems
genomic structure of h. duceuyi
gram negative diplococcus
fever, sore throat, cervical lymphadenopathy, grey/whitish plaque on pharynx which isnt scrappable
diptheria
cultured on loffler or tellurite medium
how to exotoxin produced by diptheria cause symptoms
adenosine diphosphate ribosylation of elongation factor 2
causative organism of infection from indwelling medical devices
staph epidermidis, enterococcus
grows on bile esculin agar
enterococcus
(gram positive, catalase negative, group A strep, optochin negative)
vaccine causes antibody production against polyribosylribitol and phosphate type b capsule
h. influenza
most common causative organism of infective endocarditis in patients on dialysis and IVDU
staph aureus
haemolysin virulence factor
staph aureus
h. influenza virulence factor
virulent capsule + cleavage of IgA
single stranded, negative sense, linear, non- segmented RNA
paramyxoviruses
(enveloped and helical)
what part of the epithelium does HPV affect
stratum basale
what virus is a risk factor for non-hodgkins lymphoma
hepatitic C
latency in mononuclear cells
CMV pneumonitis
- histology shows large cells with internuclear inclusions ‘owl eyes’
- double stranded linear DNA virus
activation of guanylate cyclase leading to increased intracellular cGMP
e.coli (travellers diarrhoea)
production of leithinase causing cell membrane destruction
alpha toxin by clostridium perfringes
genomic structure of the causative organism of cat scratch disease
bartonella spp.
gram negative bacilli
gram negative baccilus responsible for infection after rat bite
streptobacillus moniliformis
genomic structure of clostridium botulism
gram positive, spore forming anaerobic bacilli
tennis racket appearance on microscopy
clostridium botulism
(gram positive, rods spore forming anaerobe)
virulence factor of cryptococcus neoformans
polysacharide capsule formation
causative organism of meningitis after exposure to pigeon droppings
cryptococcus neoformans
corkscrew shaped spirochete
borrelia burgdorferi
cyclical fevers and recent travel
plasmodium falciparum
UTI negative for nitrite and grows on bile esculin agar
enterococcus
toxin produced by what bacteria works by inactivating ribosomes
shigella and e.coli
toxin produced by what bacteria acts by over stimulating adenylate cyclase
bordetella pertusis
what is the infective form of toxoplasmosis gondii
tachyzoites (bradyzoites are non transmittable and represent chronic infection)
