PSEUDOMONAS
Introduction
 Large group of aerobic
non sporing
gram negative
motile by polar flagella
ubiquitous
 oppurtunistic infections
 newer genera-Burkholderia
Stenotrophomonas
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Species
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Pseuomonas aeruginosa
Stenotrophomonas maltophila
Burkholderia cepacia
Burkholderia mallei
Burkholderia pseudomallei
Pseudomonas aeruginosa
 Morphology
slender,Gram negative bacillus
 size-1.5 microns-3*1.5microns
 motile by polar flagella
 non capsulated though some mucoid
strains may sometimes occur
 some are pilated
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Cultural characteristics
Obligate aerobe
 Wide range of temperature 5°c-42°c
optimum 37°c
 Ordinary media –
large,opaque,irregular,with distinctive
musty,mawkish,earthy smell
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Cont..
Nutrient agar Colonies are smooth,large,translucent,low
convex,2-4mm in diameter.
 Produce sweetish aromatic odour
 Greenish blue pigment diffuses
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Cont..
Blood agar
 Similar to nutrient agar
 Many are haemolytic
 Mac conkey agar
 Colourless,non lactose fermenters
 Cetrimide agar
 selective media
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Pigment production
Pyocyanin
 Bluish green phenazine pigment
 Soluble in chloroform and water
 Not produced by other species
 Pyoverdin(fluorescin)
 It is a greenish yellow pigment
 Insoluble in chloroform but soluble in water
 Produced by many other species
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Pyocyanin
Pyoverdin
Cont..
Pyorubin
 Reddish brown pigment
 Insoluble in chloroform but soluble in water
 pyomelanin
 Brown to black pigment
 Production is uncommon
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Biochemical reactions
O/F test-oxidative
 Catalase-positive
 Oxidase-positive
 Nitrate reduction-positive
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Cont..
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Indole test-negative
Methyl red test-negative
Vp test-negative
Citrate test-positive
Urease test-negative
Cont…
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Sugar fermentation tests
Glucose-only acid
Lactose-negative
Sucrose-negative
Mannitol-negative
Resistance
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Susceptible to
heat,killed at 55°c in one hour
acids
beta glutarldehyde
Silver salts
strong phenolic disinfectants
So,silver sulphonamide as a topical cream in
burns is used
Cont…

Resistant to
chemical agents
common antiseptics
disinfectants -ammonium compounds
chlroxylenol
hexachlorophane
antibiotics -aminoglycosides
cephalosporins
pencillins
Antigenic structure
 O antigens
Possesses 19 distinct,group specific O antigens
 Heat labile
 H antigens
 Two heat labile antigens recognised in
Ps.aeruginosa
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Toxins and enzymes
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Extracellular products
Pyocyanin inhibits mitochondrial enzymes and causes
disruption and cessation of ciliary beat on ciliated nasal
epthelium
Extracellular enzymes and haemolysins
Produces proteases,haemolysins and lipases
Exotoxins
Produces two exotoxns A and S
Endotoxins
It is a lipopolysaccharide have pyrogenic action
Typing methods
Bacteriocin typing
 Three types of bacteriocins are produced-R,F,S
 Pyocin produced by test strain is employed to
assess the growth inhibition of 13
 Depending upon the growth inhibition of 13
indicators strains,105 types are recognised
 Most popular method used
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Cont..
Phage typing
 Serotyping
based on O and H,17 serotypes of
Ps.aeruginosa are recognised
 Molecular Method
Restriction endonuclease typing with
pulsed-field gel electrophoresis(PAGE) is most
reliable

PATHOGENESIS
Important agent in causing nosocomial
infections
 Most common infections are
 Urinary tract infections following catheterisation
 Acute purulent meningitis following lumbar
puncture
 Post-tracheostomy pulmonary infection
 Septicaemia in debilitated patients
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cont..
Wound and burn infections
 Chronic otitis media and otitis externa
 Eye infections
 Acute necrotising vasculitis
 Infantile diarrhoea
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Mechanism Of Pathogenesis
Caused by
exotoxins,proteases,elastases,haemolysins,lip
ases and enterotoxins
 Exotoxin A-lethal toxin
 Elastases-haemorrhagic lesions
 Enterotoxins-diarrhoeal disease
 Slime layer acts as a capsule and enhances
virulence
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Thank you
HAEMOPHILUS

INTRODUCTION
HAEMOPHILUS
INFLUENZAE
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MORPHOLOGY
SMALL [ 1.0 X 0.3 MICRONS]
GRAM NEGATIVE
NON MOTILE
NON SPORING
EXHIBIT PLEOMORPHISM
CULTURAL
CHARACTERISTICS
FACTOR X
FACTOR V
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HEAT STABLE
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HEAT LABILE
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HEMIN
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BACTERIAL
VITAMIN
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AEROBIC
RESPIRATION
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ANEROBIC
RESPIRATION
CONT…
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AEROBIC
GROWS ANEROBICALLY ALSO
OPTIMUM TEMPERATURE-37C
SOME STRAINS REQUIRE 10% CO2
BLOOD AGAR-SCANTY GROWTH
SATELLITISM
Staph.aureus is streaked across a plate of
blood agar on which a specimen containing
H.influenzae has inoculated
 After overnight incubation Colonies
large -along the streak of Staph.aureus
small –farther away
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satellitism
CONT…
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LEVINTHAL`S MEDIUM
Boiling and filtering a mixture of blood and
nutrient broth
Capsulated strains produce translucent colonies
FILDES AGAR
By adding a peptic digest of blood to nutrient
agar
Best for primary isolation
Copious growth
BIOCHEMICAL REACTIONS
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Catalase-positive
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Oxidase-positive
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Glucose,Xylose-fermented with acid
production
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Lactose,Sucrose,Mannitol-not fermented
RESISTANCE
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Destroyed by heating
refrigeration
drying
disinfectants
Cultures may be preserved for about a
month on choclate agar slopes in screw
capped bottles
Long term preservation –culture may be
lyophilised
ANTIGENIC PROPERTIES
3 Major surface antigens
Capsular polysaccharide
Outer membrane protien
Lipo oligosaccharide
Major antigenic determinant of capsulated strains
Capsular polysaccharide
Pittman classified into 6 capsular strains i.e type
a to f
•Meningitis belong to type b strain
•Type b strain contains pentose sugars
ribose &ribitol instead of hexoses &
hexosamines in other 5 serotypes
•Capsular polyribosyl ribitol
phosphate antigen of Hib induces
IgG IgM IgA antibodies which are
bactericidal and protective
CONT….
Strains lacking a capsule cannot be typed
and are called NON TYPABLE
STRAINS
 Outer membrane protein antigens of H
influenzae type b have been classified into
13 sub types
 Lipo oligosaccharides are antigenically
complex
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PATHOGENECITY
Exclusively human pathogen
 Not pathogenic for animals but intra
peritoneal inoculation of large doses is fatal
in mice,guinea pigs &rabbits
 Diseases due to H influnzae considered
under 2 groups –invasive and non invasive

INVASIVE
•Spread through
Blood
NON INVASIVE
•Spread through local
invasion
•Meningitis,arthritis, •Otitis media,sinusitis
endocardits,conjuctivit
is,pancarditis
•Seen in children
•Seen in adults
•Caused by capsulated •Caused by non
strains
capsulated strains
CLINICAL MANIFESTATIONS
MENINGITIS
 Bacilli reach meninges from nasopharynx
through blood stream
 Common in children
LARYNGO EPIGLOTTIS
 Acute inflammaton of epiglottis with obstructive
laryngitis
 Children above 2 years
CONT….
PNEUMONIA
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Infants accompanied by empyema
Older children & adults by lobar pneumonia
These are primary infections due to
capsulated strains
Broncho pneumonia may occur as
secondary infection due to non capsulated
strains
CONT…
SUPPURATIVE LESIONS
 Arthritis,endocarditis& pericarditis may result
from hematogenous dissemination
 Otitis media occurs by direct spread from
nasopharynx
BRONCHITIS
 Associated with pneumococci in acute
exacerbationof chronic bronchitis
&bronchiectasis
LAB DIAGNOSIS
1.SPECIMENS
 CSF
 Blood
 Throat swab
 Sputum
 Pus
 Aspirates from joints ,middle ears
2.COLLECTION &TRANSPORT
Collected in sterile containers & under
aseptic conditions
 Very sensitive to low temp so should not
be refrigerated
 Transported to laboratory with out delay
 Inoculated on culture media immediately
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CONT.....
3.DIRECT MICROSCOPY
 Gram staining
 Immunoflouroscence and quellung
reaction
 Antigen detection
 Latex
agglutination
 Co-agglutination
 Counter immuno electrophoresis
CONT…
4.CULTURE
 CSF
culture
 Blood culture
 Sputum culture
5.COLONY MORPHOLOGY AND
STAINING
6.SEROTYPING
TREATMENT
Cefotaxime & Ceftazidime is the drug of
choice for meningitis
 Ampicillin &Cotrimoxazole –respiratory
infections
 Amoxycillin - clavulanate or clarithromycin
is more effective
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EPIDEMIOLOGY &
PREVENTION
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Infection transmitted by respiratory route
Immunity is type specific
Active immunization with Hib PRP vaccine
is indicated
Conjugate Hib PRP is used for younger
children
Rifampicin -4 days prevents secondary
infection in contacts & also eradicates
carrier state
Haemophilus aegyptius
KOCH –WEEKS BACILLUS
 Non capsulated
 Causes highly contagious form of
conjuctivitis [ pink eye ]
 Causative agent of Brazilian purpuric fever
[BPF]
 Responds to local sulphanamides &
gentamicin
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Haemophilus ducreyi
Ducrey demonstrated in chancroid lesions
 Short ,ovoid bacillus
 Gram nagative often may appear gram positive
& frequently show bipolar staining
 May be arranged in small groups or whorls or in
parallel chains giving a SCHOOL OF FISH or
RAIL ROAD TRACK appearance
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CONT…
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Can be grown on fresh clotted rabbit blood
May also grown on chorio allontioc membrane
of chick embryo
On choclate agar enriched with isovitalex and
fetal calf serum & containing vancomycin as a
selective agent
Forms small ,grey ,translucent colonies after
incubation at 35 c under 10 % co2 & high
humidity in 2 – 8 days
CONT…
Antigenically homogenous
 Cultures may be identified by agglutinatoin
with anti serum
 Susceptible to sulphonamides & many
antibiotics
 Erythromycin ,Cotrimoxazole
,Ciprofloxacin may be used for treatment
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Choclate agar
Haemophilus parainfluenzae
Requires factor V & not the factor X
 Commensel in the upper respiratory tract
 Causes bacterial endocarditis ,urethritis
,acute pharyngitis
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Haemophilus haemolyticus
Requires both factor X & V
 Commensal of upper respiratory tract
 Strains that donot require factor X have
been designated as H parahaemolyticus
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Haemophilus aphrophilus
Requires factor X but not factor V
 Cause bacterial endocarditis ,brain abscess
,sinuisitis pneumonia
 Strains requiring factor V but not factor X
have been termed as H paraaphrophilus
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HACEK group bacteria
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Fastidious slow growing bacteria
H-
Haemophilus species
ACE-
Cardiobacterium hominis
K -
Kingella kingae
Actinobacillus
Eikenella corrodens