Bacteriology- Miscellaneous Flashcards
Which organism is called pfeiffer bacillus?
H. influenzae
Virulence factor of H. influenzae
Outer membrane protein
pili
Lipooligosaccharides
Capsular polysaccharides (only Hib)
Treatment for H. influenzae
Cefotaxime, Ceftriaxone
Satellitism
Shown by H influenzae
Requires factor V and X
In the center- S. aureus
S aureus causes hemolysis– release of factors- H influenza growns
Culture media for H. ducreyi
Chocolate agar supplemented with isovitalex, fetal calf serum
Treatment for H. ducreyi
Azithromycin
Factor V and X requirement by different Hemophilus species
H. influenzae, H. aegypticus, H. hemolyticus requires both
H. ducreyi requires X only
H. parahemolyticus requires V only
Whooping cough is aka
100 day cough
Stages of whooping cough
Catarrhal- dry cough, fever, maximum infectivity
Paroxysmal- whoop cough
Convalescent- recovery stage
Pertussis toxin MOA
Increased cAMP
Treatment of whooping cough
Azithromycin
Erythromycin
Prevention of whooping cough
Acellular vaccine
Has FHA, AGG, PT, PERT
Culture media used for Bordatella
What is its appearance?
Bordet gengou medium
Bisected pearls/ mercury drops appearance
Aluminium paint appearance on confluence
Appearance of Bordatella on microscopy
Thumb print appearance
Brucella catalase, oxidase, urease status
All are positive
‘COU positive’
Triad of Brucella
Night sweats
Arthritis
HSM
Platelets may be decreased
Diagnosis of Brucella in animals
Milk ring test- purple color ring +
Diagnosis of Brucella in humans
Standard agglutination test
Detects IgM and IgG antibodies
IgM antibodies are destroyed using 2-Mercaptoethanol
Treatment of Brucella
Doxycycline x 45 days + Streptomycin IM daily x 14 days
Difference in structure between Treponema, Borrelia, Leptospira
Treponema- Tight coils
Borrelia- Loose spirals
Leptospira- hooked ends
Primary syphillis features
Painless ulcer, hard chancre, painless LN
Secondary syphillis features
condylomata lata
rash
Tertiary syphillis features
Gumma (granuloma)
Tree bark aorta, AR
Paresis
Microscopy of T. pallidum
Dark field microscope
Silver impregnation- Levaditi, Fontana stain
Non specific diagnostic vs specific tests for syphillis
Non specific-
Wasserman test, Kahn test, VDRL, RPR
Specific-
FTA-ABS, TPPA, TPHA, TPI
VDRL vs RPR
VDRL requires a serum (which needs preheating),
It requires cardiolipin ag (should be used within 24 hrs)
It is a slide agglutination test
RPR is a card test. None of these are required
What is cardiolipin ag?
It is a purified lipid extract of beef heart + lecithin + cholesterol
Which test is more sensitive in primary syphilis?
RPR is more sensitive than VDRL in early infection.
Which test is used for neurosyphilis?
VDRL is preferred for CSF analysis (RPR is not validated for CSF).
Most sensitive specific/ confirmatory test for syphillis?
FTA-ABS
Most specific among the specific tests for syphillis
TPI > TPPA
Treatment for syphillis
Benzathine penicillin
Borrelia can cause what diseases?
Epidemic louse borne relapsing fever- by B. recurrentis
Endemic tick born relapsing fever by B. duttoni
Treatment of Borrelia
Tetracyclines, Chloramphenicol
Collect blood sample during fever
Borrelia vincentii causes
Vincent’s angina
Leptospira causes
Weil’s disease/ Hepatorenal syndrome/ Ictero-Hemorrhagic fever
On culture of Leptospira on ____ medium, it produces ______
EMJH
Dinger’s ring (opaque ring just below surface of media seen on 9th day of culture)
Diagnosis of Leptospira
Microscopic Agglutination test
Chlamydia are called ATP parasites because
It takes ATP from host cells
Chlamydia is an atypical bacteria because
It has no peptidoglycan cell wall
It cannot be cultured
Chlamydia has ______ inclusions
Basophilic bacterial inclusions
2 forms of chlamydia
Elementary body- for entry/ exit of cell- has DNA=RNA
Reticulate body- for replication- has RNA> DNA
C. trachomatis causing diseases
C. trachomatis serotypes A, B, Ba, C causes trachoma
C. trachomatis serotypes D, E, F, G, H, I, J, K causes Non gonococcal urethritis, Inclusion conjunctivitis, Ophthalmia neonatorum
C. trachomatis serotypes L1, L2, L3 causes Lymphogranuloma venereum
Borrelia causes
Borrelia burgdorferi causes Lyme disease
Borrelia causes relapsing fever
Lyme disease is transmitted by bite of
Ixodid ticks/ hard ticks
Localised infection of Lyme disease appearance
Bull’s eye/ annular/ target rash
(Erythema chronicum migrans)
Lymphogranuloma venereum
‘ABCDEFG’
Asymptomatic usually
Buboes- painful LN
C. trachomatis L1, L2, L3; Conjunctivitis, Urethritis, Polyarthritis (Reiter’s syndrome)
Doxycycline tx
Esthiomene- rectal and vulvar strictures +
Freis test (skin test for LGV), Complication: Fitz Hugh Curtis Syndrome
Groove sign
C. pneumoniae has one strain called
TWAR strain
Halber staeder bodies seen in
Trachoma
Rash in rickettsia start from ____ and goes to ____
Trunk–> peripheries
except RMSF- peripheries to trunk
Levinthal Cole Lille bodies seen in
C. psittaci
Rickettsiae causing diseases and their causative species with vectors
Epidemic typhus
Endemic typhus
Rickettsial pox
RMSF
Indian tick typhus
African tick typhus
Scrub typhus
Epidemic typhus- R. prowazekii- louse
Endemic typhus- R. typhi- flea
Rickettsial pox- R. akari- mite
RMSF- R. rickettsii- tick
Indian tick typhus- R. conori- tick
African tick typhus- R. africase- tick
Scrub typhus- Orientia tsutsugamushi- mite
Brill Zinsser disease
Recrudescent typhus/ reactivation typhus
a/w Epidemic typhus
Neil Mooser reaction
AKA Tunica reaction
To differentiate R. prowazekii vs R. typhi infection
Blood inoculated in guinea pig–> scrotal inflammation if R. typhi +
Scrub typhus is vectored by larvae of ___ called _____. They are found in ____, carried by ____ and infect humans
Trombiculid mites
Chiggers
Vegetation/ shrubs
Rats/ squirrels
Special stains for Rickettsia
Giemsa, Castaneda, Machiavello, Gimenez
Chlamydia is not cultured in media because it is _______. It is instead grown in _______.
Obligate Intracellular pathogens
Cell lines, Hens eggs
Weil felix reaction
Heterophile agglutination reaction
To find Rickettsial antibodies, Proteus antigens are used (OX19, OX2, OXK) as they cross react
Only Rickettsial organism that shows positivity with OXK antigen in Weil felix reaction
Scrub typhus
Rickettsial disease that doesnt show reaction with any antigens in Weil Felix tests
Brill Zinsser reaction
Treatment of Rickettsial infections
Doxycycline/ Tetracycline
Coxiella burnetii
Belongs to Rickettsia
Intracellular parasite
No vector, rash or Weil Felix reaction
Causes Q fever
Infection by inhalation
Donut granuloma/ Fibrin ring granuloma present
Tetracycline
Bartonella baciliformis
Oroya fever/ Carrion fever
Sandfly vector
Bartonella quintana
5 day fever/ trench fever
Louse as vector
Bartonella henselae
Cat scratch disease
Bacillary angiomatosis
Peliosis (sinusoidal dilatation)
Stellate granuloma
Mycoplasma
aka Eaton’s agent
Mnemonic: ‘Mycoplasma’
My- MCCof walking pneumonia, atypical
CAP
Co- cold agglutination test +
Cell wall absent; Cell membrane has sterols
Pla- PPLO- Pleuropneumonia like organism, uses PPLO agar which has fried egg colonies. Enhanced by Diene stain
Sma- smallest
Campylobacter, Helicobacter are
Catalase and Oxidase +
Spiral organisms
Campylobacter
1. Growth at
2. Media
3. Mode of infection
4. Features
5. shape of organism
6. Motility
- 42C
- Campy BAP/ SKIRROW/ BUTZLER agar- droplet like colonies
- Contaminated poultry eating
- Diarrhoea, GBS
- Comma shaped, Gullwing shaped
- Shooting star/ darting
Helicobacter pylori causes maltoma via
cag A
vac A
H. pylori causes what type of ca?
Adenoca
Stains used for H. pylori
Warthin starry silver stain
Modified giemsa stain
H. influenzae is more common among
In children between 3 mths and 3 years
Factor V refers to ____.
Factor X refers to ______
NAD
Hemin
Acute epiglottitis appearance on direct laryngoscopy
Cherry red epiglottis
HACEK full form
Hemophilus sp (H. parainfluenzae, H. aphrophilus, H. paraphrophilus)
Aggregatibacter
Cardiobacterium
Eikenella
Kingella
Chancroid
1. AKA?
2. Diagnosis?
3. Treatment
4. IP
- Soft chancre
- Clinical diagnosis
- Azithromycin/ ceftriaxone
- 1-14 days
Causes of non gonococcal urethritis
C. trachomatis
Ureaplasma urealyticum
Adenovirus
Trichomonas (rare)
HSV (rare)
Koch Weeks bacillus
H. aegypticus
Brazilian purpuric fever
1. caused by
2. Features
3. Treatment
- H. aegypticus
- Fever, purpura, contagious conjunctivitis- can lead to fulminant septicemia and death in infants and children
- Sulfonamides/ gentamicin
