NEISSERIA AND MORAXELLA CATARRHALIS🫘 Flashcards
nonmotile, Gram-negative, diplococci with adjacent sides flattened – ‘kidney shape’ or ‘coffee bean’ shape
Neisseria and M. catarrhalis
commensals of the respiratory and urogenital tracts
M. catarrhalis and most Neisseria spp.
is transmitted via contaminated respiratory droplets
N. meningitidis
is usually attributed to the
spread of endogenous strain to normally sterile sites
M. catarrhalis
two pathogenic neisseria
N. gonorrheae
N. meningitidis
pathogenic neisseria virulence factor
Virulence factors include:
* Receptors for human transferrin * Capsule (N. meningitidis)
* Pili (fimbriae)
* Cell membrane proteins – OMPs * Lipooligosaccharide (LOS)
* IgA protease
- also known as “gonococcus”
N. gonorrheae
causes opthalmia neonatorum in infants
N. gonorrheae
- short incubation period, around 2-7 days
- manifests as acute urethritis in symptomatic males.
- sexually transmitted
- often asymptomatic in females, urethritis, cervicitis, and dyspareunia may occur
GONORRHEA
also known as “gonococcal conjunctivitis”
- Transmitted from mother to child
OPTHALMIA NEONATORUM
- colonizes the upper respiratory tract of humans
- invasive meningococci have a polysaccharide capsule
N. meningitidis
- also known as “meningococcus”
- also infects humans only
- agent of meningitis and meningococcemia * incubation period around 1-10 days
N. meningitidis
- symptoms include abrupt onset of frontal headache and photophobia
MENINGITIS
- sepsis
- may occur with or without meningitis
MENINGOCOCCEMIA
- fulminant form of meningococcemia
- death may occur within 12 to 48 hours from onset
WATERHOUSE-FRIDERICHSEN S YNDROME
- formerly ‘Branhamella catarrhalis’ and ‘Neisseria catarrhalis’
- opportunistic pathogen
- third most common cause of acute otitis media and sinusitis in children
M. catarrhalis
third most common cause of acute otitis media and sinusitis in children
M. catarrhalis
- Calcium alginate and cotton swabs are inhibitory to the organism. what is the preferred material to be used?
- Dacron and rayon swabs are preferred
_____in commercial blood culture anticoagulant, inhibitory to pathogenic Neisseria
sodium polyanetholesulfonate (SPS)
N. meningitidis specimens include:
CSF, blood, nasopharyngeal swab and aspirates, joint fluids, and less commonly, sputum and material from urogenital sites
________specimens typically include samples from middle ear effusion, nasopharynx, sinus aspirates, or bronchial aspirates
M. catarrhalis
smears for direct Gram stain for N. gonorrheae prepared from______ specimens
urogenital
true or false
demonstration of Gram-negative intracellular diplococci in symptomatic males is evidence of gonococcal infection
Truest
true or false
demonstration of Gram-negative intracellular diplococci in symptomatic females must be confirmed before complete diagnosis of gonococcal infection
true or false
demonstration of Gram-negative intracellular or extracellular diplococci from preferred specimens such as CSF aids in presumptively identifying N. meningitidis
the medium of choice for N. gonorrhea is
CAP (chocolate agar plate)
colonies are medium-sized, gray, and convex, and encapsulated strains are mucoid
has green tinge of the blood agar under the colonies
NEISSERIA AND MORAXELLA CATARRHALIS
- ____grows on SBA and chocolate agar
- colonies are smooth, opaque, gray to white colonies
M. catarrhalis
has “hockey puck” colonies
(has the ability to be slid across the agar surface without disruption, known as hockey puck sign)
M. catarrhalis
- traditional method for the identification of Neisseria spp.
Carbohydrate utilization
POSITIVE - yellow
NEGATIVE - RED
N. gonorrhea uses what sugar
glucose
N. meningitidis uses what sugar(s)
maltose and glucose
does not utilize any of the carbohydrates
M. catarrhalis
currently the only antimicrobials remaining that are recommended for the treatment of N. gonorrheae
Cephalosporins
When coinfection with C. trachomatis is present, the recommended regiment is _____
ceftriaxone plus azithromycin
- The drug of choice for treatment of N. meningitidis is
penicillin
DOC best for meningococcemia
Third-generation cephalosporins
Humans are the only natural host
N. meningitidis
NOTE: Serotypes A, B, & C are associated with epidemics of meningitis (usually type B)
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causes blood vessel destruction (hemorrhage) and sepsis
Endotoxin (LPS)
Have a unique proteins that can extract iron from transferrin, lactoferrin and hemologlobin2
N. meningitidis
N. gonorrhoeae
most severe form of meningococcemia.
high fever, shock, widespread purpura, disseminated intravascular coagulation, thrombocytopenia, and ADRENAL insufficiency -bilateral hemorrhagic destruction of the adrenal glands
Waterhouse-friderichsen syndrome
DOC for N. meningitidis
Penicillin
DOC for meningococcal meningitis and sepicemia
ceftriaxone (or cefotaxime)
prophylaxis of close contacts of infected persons
Rifampin/ciprofloxacin
The first meningococcal vaccine for serogroup____was approved in October 2014.
Serogroup B
N. meningitidis cell wall contains cytochrome oxidase which oxidizes dye _______ form colorless to deep pink.
tetramethylphenylene diamine
(applies for both Meningitidis and Gono
N. meningitidis reservoir
Upper respiratory tract.
(that’s why it is common causative agent of meningitis 2-18yrs old ppl.
Only infects humans (no immunity to repeated infections)
N. gonorrhoeae
Neisseria gonorrhoeae reservoir
human genital tract
- sexually transmitted
- passage through birth canal
NOTE: both meningitidis and gonorrhoeae are facultative anaerobe
- (meaning grows best in high CO2 environment)
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Ferments glucose only
N. gono
has endotoxin: Lipooligosaccharide (LOS)
N. gono
(N. meningitidis - EndoLPS)
can cause Perihepatitis (Fitz-Hugh-Curtis Syndrome): violin string adhesions
N. gono. (complication of PID or pelvic inflammatory disease (PID)
causative agent of Opthalmia neonatorum
(a form of conjunctivitis that affects newborn)
N. gono
Prevention of Opthalmia neonatorum
Erythromycin ointment or Silver
nitrate
(Silver nitrate is no longer used
because it can cause chemical conjunctivitis.)
most common cause of hyperacute bacterial conjunctivitis, the most severe form of conjunctivitis.
N. gonorrhoeae
Most common site of asymptomatic gonococcal infection in women:
ENDOCERVIX
N. meningitidis may also cause lesions in the joints and lungs and rarely cause massive bilateral hemorrhages in the adrenals called:
Waterhouse– Friderichsen syndrome)
It is an overwhelming and usually fatal condition, characterized by shock, disseminated intravascular coagulation (DIC) and multisystem failure
Waterhouse– Friderichsen syndrome)
the third stage of meningococcal infection, the organisms can cross the blood–brain barrier and infect the meninges.
meningitis
They grow well on chocolate agar and Mueller– Hinton agar.
N. gono
Thayer–Martin medium is what?
chocolate agar containing vancomycin, colistin and nystatin - which inhibits most contaminants, including nonpathogenic Neisseria
These proteins stimulate antibodies that block serum bactericidal activity against N. gonorrhoeae.
Rmp (protein III)
These proteins facilitate bacterial adherence to each other and to eukaryotic cells and also for the clumping of cocci seen in urethral exudate smears.
Opa protein (protein II)
The _____proteins (formerly protein I) are porin proteins that form pores or channels in the outer membrane.
Por proteins
The incubation period of N. gono
2–8 days.
Ophthalmic neonatorum can be controlled by?
instilling 1% silver nitrate solution into the eyes of all newborn babies (Crede’s method).
N. gono note: If this is not possible, specimens should be collected with charcoal impregnated swabs and sent to the laboratory in Stuart’s transport medium.
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N. gono DOC
Penicillin G
(a high concentration of typical penicillin due to bacterial resistance)
∙ It does not produce acid from glucose, maltose, sucrose, lactose or fructose
∙ It reduces nitrate to nitrite.
M. catarrhalis
They are aerobes. Most strains grow on nutrient agar, blood agar or chocolate agar.
Moraxella (Branhamella) Catarrhalis
They form part of the normal pharyngeal flora but can cause respiratory infections, including otitis media, sinusitis atbp.
M. catarrhalis
- Why is cotton swab discourage in N. gono specimen collection?
- Give alternative
- Bc it contains fatty acids which is toxic to the bacteria
- Dacron rayon, calcium alginate or cotton swabs treated with charcoal
consists of a flat bottle with modified Thayer-Martin and a bottle under increased carbon dioxide
Transgrow bottles
consists of a flat plastic dish containing a medium selective for gonococci and a tablet that acts as a carbon dioxide generator
JEMBEC (JohnE.MartinBiological Environmental Chamber)
what is a MODIFIED Thayer Martin Agar (MTM)?
Same as TMA (CAP with vancomycin, colistin, and nystatin) BUT with the addition of TRIMETHOPRIM LACTATE
(to suppress swarming of proteus spp.)
what is Martin Lewis Medium (ML)
- All MTM components except nystatin which is substituted by anisomycin
- Vancomycin concentration is increased
New York City Medium (NYC)🐴🩸
A transparent medium with lysed horse blood, horse plasma and yeast dialysate
Appears pink in Beta Lactamase test/Cephalosporinase Test:
N. meningitidis
Postive in Gamma-glutamyl aminopeptidase Test
N. meningitidis
48-hour colony maybe have elevated center, thinner wavelike periphery
“wagon wheels” appearance
Moraxella catarrhalis
Does not utilize any sugar in CHO utilization test
Moraxella catarrhalis
However positive sya sa DNase unlike N. gono and N. meningi
Those bacteria that are phagocytized by the PMN’s are protected from intracellular killing by the bacterial _____.
PorB protein
PorB prevents the fusion of the lysosome with the phagosome and allows the bacteria to, for a time, survive in the PMN.
most common cause of acute conjunctivitis. The most severe form of conjunctivitis
N. gono
