Microbiology Flashcards
Serotyping by slide agglutination to which strains of E.Coli
EPEC & EHEC
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what causes infection when leave the intestine
Proteus
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in EHEC we detect the vero toxin by …… and detect the organism by …….
ELISA
Immunoflourescence in stools
indicators of fecal pollution of water
E.Coli, Enterococcus faecalis and
Cl. perfringens
klebsiella are normal inhabitants in
intestine and respiratory tract
causes inclusion conjunctivitis and which serotypes
C. trachomatis and serotypes D-K
Klebsiella are in soil and water as
Saprophytes
meaning of nosocomial?
orginating in hospital
Hospital acuired diseases
Klebsiella causing nosocomial diseases in man due to
multi-drug resistant strains
how many serotypes of klebsiella
77 based on the capsular polysaccharide
the non lactose fermenters
Slamonella, shigella, proteus
why collonies of Klebsiella are mucoid
due to production of abundant extracellular slime by the capsule
biochemical activities of klebsiella
- the ferment glucose maltose sucrose luctose, mannite, and salicin
- they are indole negative/ VP positive/MR negative/ citrate positive
what diseases caused by K.penumonia
lopar pneumonia
neonatal meningitis
septicemia
urinary track infection
hospital acquired infection
kill mice in 24-48 hours when injected intra-peritoneal
causes Rhinoscleroma
k. rhinoscleromatis
causes atrophic rhinitis
K. ozaenae
K. causes hospital acuired infection
K. oxytoca
oxygen in hospital, oxytoca in hospital
enterobacter, citrobacter, serratia
- they are in soil, water, stool
- causes urinary tract, wound, and blood streams infections to hospitalized patients, immunocomromised especially those under invasive procedure such as respiratory intuubation, intravenous and urinary catheters
- gram negative bacilli, motile, and differentiated by thier biochemical activities
Proteus are found in ……….. and are inhabitants of ……….
soil and water
intestine in man
- oxidase positive
- don’t ferment any sugar
- Acid is produced from glucose by oxidation only
Pseudomonas
when proteus cause infection
when they leave intestine
the two important species of proteus
P. vulgaris
P. mirabilis
Diseases caused by proteus
- Urinary tract infection caused by proteus mirabilis
- wound infection
- pneumonia
- meningitis
- otitis media
- bacteremia
what require antibiotic sensitivity test
proteus
morganella morgani
providencia rettgeri
why we make urease test in proteus
to differentiate between salmonella and shigella
Urease positive
what is phenylalanine deaminase positive?
Proteus
morganella morgani
providencia rettgeri
what cause hospital acquired infections
E.coli
Klebsiella
Proteus
Morganella morgani
Providencia rettgeri
Produce H2S
Proteus
Causes reiter’s syndrome
C. trachomatis
what is Reiter’s syndrome
UAU (Urethritis, Arthritis, Uveitis)
It is an autoimmune disease caused by antibodies formed against C. trachomatis cross - reacting with antigens on the cells of urethra, joint, uveal
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Urease positive
Klebsiella
Proteus
Morganella Morganii
Providencia Rettgeri
Ureaplasma urealyticum
Non-lactose fermenters
Salmonella
Shigella
Proteus
Morganella Morganii
Providencia rettgeri
lactose fermenters
Escherichia
Klebsiella
Enterobacter
late lactose fermenters
Sh. sonnei, Citrobacter, Provedentia
Enteroinvasive E.Coli
the virulence factors of E.coli
- pili or colonization factor
- Capsule
- Endotoxin
- Exotoxin
- Verotoxin or shigatoxin
the virulence factors that genetically carried on plasmids
Pili
Enterotoxins (Exotoxins)
has exotoxin A: that is similar to diphetria toxin anf causes tissue necrosis
pseudomonas
pili of e.coli
- enables the organism to adhere to mucosal cells
- it is genetically carried in plasmids
Capsule of E.coli
Function
enterferes with phagocytosis
Endotoxic of E coli
It is a lipopolysaccharide that causes endotoxic manifestation (shock, hypotension, fever)
Verotoxin or Shiga toxin produced by
by enterohaemorrgic E Coli strains
has a sweet grape like odour
Pseudomonas
what are the virulence factors of Uropathogenic E coli
Pili with adhesive proteins
K antigens
exotoxins(haemolysins)
has capsular antigen K1
E.coli strains that causes
Causes infantile diarrhea
Enterotoxigenic
Enteropathogenic
require pyocin typing in diagnosis for epidimiologic purposes
pseudomonas
are obligate intracellular parasites?
Chlamydiae
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Serotypes D-K causes
inclusion conjunctivitis
Genital infections
1. NGU and epididymitis in males
2. cervicitis, salpingitis, pelvic inflammatory disease
bacteria that can not synthesize ATP
Chlamydiae
causing travellers diarrhea
Enterotoxigenic E.coli
Has LT and ST exotoxins
Enterotoxigenic
causes dysentry like diarrhea
Enteroinvasive
has serotypes O26, Om, O55
Enteropathogenic
Causes acute and persistent diarrhea in children and HIV patients
Enteroaggregative
Causes
- traveler’s diarrhea
- causes neonatal diarrhea(infantile diarrhea)
- dysentry like diarrhea
- Bloddy diarrhea
- Acute and persistent diarrhea in children and HIV
- Enterotoxigenic
- Enterotoxiegenic and Enteropathogenic
- Enteroinvasive
- Enterohaemorragic
- Enteroaggregative
E.col strain
Like shigella, non-lactose and non motile
Enteroinvasive
- adheres to intestinal epi. by pili
- adheres to intestinal epi. and loss of micro vill and cupping of cells around bacteria
- invasion of epithelium
- haemorrhagic colitis
- aggregative adherence to mucosa in patches
- enterotoxigenic
- enteropathogenic
- entero invasive
- Enterohaemorrhagic
- Enteroaggregative
E.coli strain
identified by DNA probes and He-p2 cell cultures
Enteroaggregative
Has serotype 0157:H7
Enterohemorrhagic
has greenish coloration of culture due to its diffusible exopigments
pseudomonas
the commonest pathogen of pseudomonas
P. aeruginosa
infections caused by pseudomonas
- Urinary tract inf
- wound inf
- otitis externa
- corneal ulcer in contact lens users
- pneumonia
- sepsis with ecthyma gangrenosum
- osteomyelitis and endocarditis in IV drug users
Morphology pf pseudomonas
Gram negative motile bacili
Virulence factors of pseudomonas
- Pili
- Endotoxin
- Enzymes (elastase and protease), that facilitate
invasion. - Exotoxin A: very similar to diphtheria toxin in its
action and causes tissue necrosis
Caused by serotypes A, B, C of Chlamydiae trachomatis
Trachoma
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From chlamydiae: Causes atherosclerotic coronary artery and cardiovascular disease
Chlamydiae pneumoniae
Causes Neonatal pneumonia acquired from birth canal from infected mother
C. Trachomatis
causes also pneumonitis in immunocompromised patients
Which strain can live in a biofilm away from antibodies and phagocytosis
pseudomonas strains isolated from cystic fibrosis
because it has exopolysachride (glycocalyx)
the three species of chlamydiae
1) chlamydiae trachomatis
2) chlamydiae psittaci
3) Chl. pneumoniae
Causes psittacosis that may be transmitted to man
Chl. psittaci
causes atypical pneumonia
Chl. pneumonia
Chlamydia trachomatis
ocular, genital and respiratory infection
Trachomatous (تراكم نظري عملي تنفسي)
what is called the infectious form of Chlamydiae and the growing form of it
Elementary body
Initial or reticulate body
what staining and culture of Chlamydiae
- they are stained with Giemsa or Macchiavello stain
- they grow in tissue culture and in yolk sac oif chick embryo
Diseases caused by C. trachomatis
I- Ocular infections:
1- Trachoma
2- Inclusion conjunctivitis
II- Genital infections: non-gonococcal urethritis
III- Lymphogranuloma venereum (LGV)
IV- Respiratory infection
Diseases caused by C. trachomatis
I- Ocular infections:
1- Trachoma
2- Inclusion conjunctivitis
II- Genital infections: non-gonococcal urethritis
III- Lymphogranuloma venereum (LGV)
IV- Respiratory infection
Diseases caused by C. trachomatis
I- Ocular infections:
1- Trachoma
2- Inclusion conjunctivitis
II- Genital infections: non-gonococcal urethritis
III- Lymphogranuloma venereum (LGV)
IV- Respiratory infection
what is trachoma?
It is a keratoconjunkitvits that start with acute infection of the conjunctiva and cornea that causes scarring and blindness
it is transmitted from eye to eye by fingers, fomites, flies
caused by serotypes ABC
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Genital infections of C. trachomatis
- C. trachomatis serotypes D-K is a prominent cause of nongonococcal urethritis and rarely epididymitis in males.
- In females it causes cervicitis, salpingitis and pelvic
inflammatory disease. - It can lead to sterility and predispose to ectopic
pregnancy.
which disease and which bacteria we used Frie test
LGV in C. trachomatis
What is Frie test?
it is a hypersensitivity skin test similar to tuberculin test used in diagnosis of LGV caused by C. trachomatis
which is used to diagnose chlamydial sexual transmitted diseases
Nucleic acids in specimens by DNA probes or PCR, which can be used on urine to diagnose chlamydial sexually transmitted diseases.
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are useful in diagnosis of C. pneumoniae and C. psittaci and are not useful for genital tract c. trachomatis infections
becuase trachomatis has many serotypes
serologic tests
They have corkscrew like motility
treponema pallidum
Causes Weil’s disease
Leptospira (spirochaetes)
Can be inoculated in the testicles of rabbits
Treponema Pallidum
Has a hyaluronidase
search for others has hyaluronidase
Treponema pallidum
Causes congentital syphilis?
T. pallidum (Spirochaetes)
they are pathologically occur intracellulary and extracellulary
Neisseriae Gonorrhea
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Respiratory infections of C. Trachomatis
- inclusion conjunctivitis may go otitis, pharyngitis, nasal obstruction through nasolacrimal duct
- pneumonitis in immunocompromised patients
- Neonatal pneumonia result in detection of IgM antibody titre treated by erythromycin
Respiratory infections of C. Trachomatis
- inclusion conjunctivitis may go otitis, pharyngitis, nasal obstruction through nasolacrimal duct
- pneumonitis in immunocompromised patients
- Neonatal pneumonia result in detection of IgM antibody titre treated by erythromycin
Diagnosis of Chlamydial infections
Specimens include; conjunctival and urethral discharge, cervical scrapings, sputum, urine, pus .. .etc. They are examined as follows:
1- Direct detection in the specimens of:
a- Intracytoplasmic inclusions
b- Chlamydial antigens
c- Nucleic acids in specimens by DNA probes or PCR, which can be used on urine to diagnose chlamydial sexually transmitted diseases.
2- Isolation on tissue culture
3- Serologic diagnosis
- intracytoplasmic inclusions by
- chlamydial antigens by
- nucliec acids by
- Giemsa or immunoflourescent staining
- ELISA or flouresecent antibody staining
- DNA probes or PCR
Serologic diagnosis of Chlamydia
- Detection of IgM or rising titre of IgG using CF test or ELISA
- Serologic tests are useful for C. pneumonia and C. psittaci
- are not useful for diagnosis of genital tract Chlamydial infection
the three genera of Spirochetes
Treponema, Borrelia, Leptospira
what diseases caused by the three genera of spirichaetes
Treponema pallidum causes syphilis
Borrelia causes relapsing fever and lyme disease
leptospira causes leptospirosis or Weill’s disease
the two antibodies to diagnose syphilis
Treponema antibody against treponemal antigen
Second antibody (reagin) against cardiolipin
virulence factors of T. pallidum
- outer membrane protein for adherence to the surface of host cells
- Hyaluronidase which may facilitate perivascular infiltration
primary lesion of T. palidum
Syphilis
hard painless chancre 2-10 weeks after exposure
papula which ulcerates
regional lymph nodes are enlarged
large numbers of bacteria is present in this stage
Secondary stage
Syphilis
Generalized manifestations
* chonylomata of anus and vulva
* mucous patches in the mouth
Systemic manifestations
* fever
* weight and hair loss
* joint pains
large numbers of bacteria is present in this stage
Tertiary Syphilis
Granulomas (gumma) in skin and bones
CNS: paresis and tabes dorsalis
Cardiovascular: aortitis, aneurysm of aorta
Treponemas are rarely seen in the lesions
Congenital syphilis
- A pregnant syphilitic woman can transmit T. pallidum to the foetus through the placenta.
- this may lead to abortion or still birth, oe a living baby will develop congenital syphilis in childhood manifested as interstitial keratitis, hutchinson’s teeth, saddle nose, and CNS anomalies
in congenital infection, the child make which antibody
IgM
Causes cupping of cells around bacteria
Enterpathogenic e.coli
Gram negative Diplococci arranged in pairs with adjacent flattened cells
Neisseriae Gonorrhea
culture on enriched media with heated blood like chocolate or MTM
N Gonorrhea
describe the colony of N.Gonorhea
convex
glistening
elevated
mucoid
transparent or opaque
non pigmented
non-hemolytic
all oxidase positive
N. Gonorrhea
Pseudomonas
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