Gram negative cocci Neisseria Moraxella Acenitobacter The family by dffhrtcv3

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									                           Gram negative cocci
                                 Neisseria
                                 Moraxella
                               Acenitobacter
The family Neisseriaceae consists of Gram-negative aerobic bacteria
from fourteen genera (Bergey's 2001), including Neisseria,
 . and Aquaspirillum,Kingella ,Chromobacterium
 The two medically important
 Neisseria gonorrhea
 meningitidis Neisseria

 Morphology:
 Figure
                             Neisseria gonorrhea
History:
Morphology:
Structure:
It is un-encapsulated (unlike meningoccci), piliated (pili) and non motile, and
resemble a pair of Kidney beans
• Pili :
• Lipooligosasccharide (LOS)
• Outer membrane protein (OMPS):
Pathogenicity
• dysuria, urethritis
• The organism may spread to the prostate, bladder and epididymes,
    causing inflammation and swelling. Epididymitis
• In women, N. gonorrhoeae infects the cervix (not vagina), urethra, vulva
    and rectum, and causes, dysurea and cervicitis and disseminated to
    fallopian tubes causes salpingitis (inflammation of the tubes).
• Ophthalmic neonatorum
• Rectal infection, prevalent in male homosexuals
• Pharyngitis
• Disseminated infection, septic arthritis.
Diagnosis:
Specimens:
Materials from genital sources such as urethra, cervix, and anal canal
Specimens from extra genital orpharynx , skin lesion, inflamed joints, blood,
sterile body fluid.
Swap from conjunctiva in case

Culture:
Atmosphere:

Temperature

Media: chocolate agar, blood agar
Thayer martein media=VCN
MNYC: Modified New York City: selective media.
Colonies appears:

Colonial morphology variation:
T1 T2
T3 T4
T5
Biochemical reaction:

Catalase= +ve
Oxidase= strongly oxidase positive* (Kovacs mehthod)
The cytochrome oxidase enzyme is able to oxidize the substrate
tetramethyl-p-phenyledediamine dihydrochloride, end products
indophenols end results dark purple end
Sugar fermentation: ferment glucose only*
          Species Glu Lact Mal Suc
    N. gonorrhoeae         A        -       -       -
    N. meningitidis        A        -      A        -
Hiss serum *
Serological diagnosis:
Rapid acidometric filter paper test to detect betalactamase activity:
crystalline penicillin brocresol purple solution ,, a yellow color indicate the
production of penicilloic acid from break down penicillin by B-lactamase

Antibiotic sensitivity: *resistant to penicillin, tetracycline, cefoxitin
Treatment with third generation of cephalosporin (ceftriaxone)
Nutritional variant gonococci:
 Another features of N. gonorrhoeae (auxotype) certain strains of
gonococci require the addition of particular defined nutrient to grow on
artificial media , those strains that require arginine, hypoxanthine, and
uracl (AUH-dependant auxotypes)
                         Neisseria meningitidis
Morphology:
Structure:
Serogroups:14 capsular polysaccharide types called
    serogroups.
A, B, C, W135 and Y,
Serotypes: outer membrane proteins (OMPS) and LOS.
lipo-polysaccharide layer producing enterotoxins
Virulence factors:
     • Pili (fembri)
     • Polysaccharides capsules
     • Lipopolysacharides:
     Pathogenesis:
     • meningitis:
     • septicemia:
     fulminant septicemia, (sever septicemia and shock for which
        endotoxin is released) after bacteremia it occurs
     acute fulminating meningococcal septicemia seen mainly in very
        young children reefer to as waterhouse-Fridechsen
        syndrome,
     meningococcal arthritis and endocarditis
  Diagnosis
Specimens
CSF, skin lesion, Blood
(Processing of CSF)

Culture:
Atmosphere:
Temperature

Media: chocolate agar, blood agar
Thayer martein media=VCN
MNYC: Modified New York City: selective media.
Colonies appears:
Biochemical reaction:

Catalase= +ve
Oxidase= strongly oxidase positive* (Kovacs mehthod)
The cytochrome oxidase enzyme is able to oxidize the substrate
tetramethyl-p-phenyledediamine dihydrochloride, end products
indophenols end results dark purple end

Sugar fermentation: ferment glucose only*

          Species    Glu   Lact   Mal   Suc
   N. gonorrhoeae     A       -     -       -
   N. meningitidis    A       -    A        -


Hiss serum *
Treatment:

treated with Penicillin or one of Cephalosporines (cefotaxime or
   ceftriaxone)
diagnosis action is very important, direct microscopic examination
latex agglutination
serogroups-specific anti-capsular antibody can be used to obtain rapid and
   presumptive identification of serogroups specific meningococcal
vaccines:
    a capsular vaccines for serogroups A, C, W, and Y is very
       effective used during the out break of meningococcal
       meningitis due to serogroups A and C, give polyvalent
       vaccine (A,C,Y, W 135) (The vaccine is valid to 3-5 years).
    the polysaccharides serogroups of B dose not elicit an effective
       immune response protection can be generated by vaccines to
       polysaccharide capsules is short living young children
    prophylaxis: rhifampin is usually used to treat family member of an
       infected individual the drug is effective in eliminating the carrier
       state
               Oxid     G     M     Plasmi   Vaccin    Poly       B-
               ase    fern   fern      d       e      Capsu   latamase
                                                        le
Neisseria       +      +      +     Rare     A,C,W,    +       None
meningitidis                                   Y
Neisseria       +      +            Comm      no       no     common
gonorrhea                            on
                          Moraxella catarrhalis
                         Formerly Branhamella
Morphology: gram negative diplococci (coco bacilli) as Neisseria but
differences is not found inside pus cells.
  Aerobic, oxidase Catalase positive. fastidious organism, that doesn't
                          ferment carbohydrates
Habitat: normal flora of the urogenital tract, respiratory
Phathogenicity:
Respiratory infection , Middle ear, Eye, CNS, Joints
Diagnosis
Culture:
Catalase, Oxidase ,DNAS positive
Sugar: not utilize sugar.
Antibiotic sensitivity:
Resistant to penicillin, and sensitive to erythromycin, tetracycline and
trimethoprim.
                             Acinetobacter

Non motile cocobacilli that are frequently confused with Neisseria in
gram stain., capsulated, oxidase negative, obligatory aerobic and don’t
ferment cho
Habitat: environment and human can affect any body sites, but with
low virulent, mainly to immunity of patients
Isolation of the organism from clinical specimens alone even doesn't
signify the etiology it depends on the patient cases and treatment it is
resistant to many of antibiotics, so treatment depends on the patient
cases and antibiotic sensitivity test


Biochemical reaction
Catalase positive
Oxidase negative
Can be Cultured on MaConky

								
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