SEMIFINAL: Neisseria & Moraxella Flashcards
All species are cytochrome oxidase and catalase positive except for?
N. elongata subsp. nitroreducens and N. bacilliformis
Considered second most
commonly reported STDs
Gonorrhea
Localized to the mucosal surfaces (urethra, endocervix, anal canal, pharynx, and conjunctiva)
Neisseria gonorrhoeae
This may cause sterility, ectopic pregnancy, or perihepatitis (Fitz-Hugh–Curtis syndrome)
Pelvic inflammatory disease
A gonococcal eye infection during vaginal delivery through an infected birth canal
Ophthalmia neonatorum
Treatment for opthalmia neonatorum
Antimicrobial eye drops, generally erythromycin
These species of Neisseria is exclusively found only in
humans
N. meningitidis & N. gonorrhoeae
When N. meningitidis enters the bloodstream, two main diseases can occur
fulminant meningococcemia & meningitis
This may occur with or without meningitis and carries a 25% mortality rate, even if treated
Meningococcemia, or sepsis
Hemorrhaging of blood into skin and mucous
membranes, producing bruises
Purpura
Enumerate the virulence factors of Neisseria
- Receptors for human transferrin
- Capsule (N. meningitidis)
- Pili (fimbriae)
- Cell membrane proteins
- Lipooligosaccharide (LOS) or endotoxin
- Immunoglobulin A (IgA) protease
Fine hairlike projections that are important in the initial attachment of the organism to host tissues
Pili (fimbriae)
Inhibit phagocytosis of the organism by neutrophils and aid in the exchange of genetic material between cells
Pili (fimbriae)
Possesses a polysaccharide capsule that is antiphagocytic and serves as an important virulence factor
N. meningitidis
Similar to lipopolysaccharide of enteric gram-negative bacilli and helps in the organism’s evasion of the complement mediated cell lysis
Lipooligosaccharide
Other Neisseria spp.
- Saprophytic Neisseria
- Normal microbiota in respiratory culture
It is extremely susceptible to drying and temperature change
N. gonorrhoeae
Reduced recovery of N. gonorrhoeae may result as soon as _________ after collection
30 minutes
When inoculated swabs are used in collecting neisseria samples, what transport system must be used?
Amie’s medium with charcoal
What swabs are preffered for collecting neissseria samples?
Dacron or rayon swabs
Why are calcium alginate and cotton swabs not used for collecting neisseria samples?
Because they are inhibitory to N. gonorrhoeae
IDENTIFY:
Otitis media (young children)
Chronic upper respiratory infection
Moraxella catarrhalis
These are aerobic, nonmotile, non–spore-forming, gram- negative diplococci.
Neisseria
What is needed in order to grow Neisseria?
Carbon dioxide because Neisseria is capnophilic
These are plates utilize for bedside plating
Jembec Plates
These are sensitive to sodium polyanethol sulfunate which is found in blood culture bottle
N. gonorrhoeae & N. meningitidis
If a blood culture broth is inoculated, the SPS content should not exceed?
0.025%
If blood is first collected in vacutainer tubes containing the SPS, the specimen must be transferred to the broth cultured system within
1 hour of collection
Appearance of neisseria when gram stained
Kidney-shaped or coffee- bean shaped diplococci
This is diagnostic especially from a urethral discharge specimen, in men only
Gram negative diplococci inside a poymorphonuclear leukocytes
This should not be gram stained because nonpathogenic commensal Neisseria may be present and this is not diagnostic of the infection
Pharyngeal specimen
In symptomatic females, this is only presumptive evidence of gonococcal infection
direct examination of endocervical secretion
What is the media of choice for neisseria?
- Trypticase soy agar with 5 % sheep blood
- Chocolate Agar (CA)
- Selective medium
such as:
Thayer-martin medium
MTM
Martin-Lewis
GC-LECT
NYC medium
Has chocolate agar as base; enriched with IsoVitaleX supplement
Thayer- Martin
This inihibits gram-negative bacteria in Thayer-Martin
Colistin
This inhibits yeast in Thayer-Martin
Nystatin
This inhibits gram-positive bacteria in Thayer-Martin
Vancomycin
What are the antibiotics or inhibitory agents of Thayer-Martin?
- Vancomycin
- Colistin
- Nystatin
This inhibits swarming Proteus spp. in MTM
Trimethoprim
What are the antibiotics or inhibitory agents of Martin Lewis?
- Colistin
- Anisomycin
- Vancomycin
What are the antibiotics or inhibitory agents of MTM?
- Colistin
- Nystatin
- Trimethoprim
Contains additional antimicrobials to inhibit bacteria found in oropharyngeal specimen specifically N. meningitidis
GC-LECT
What are the antibiotics or inhibitory agents of GC-LECT?
- Colistin
- Amphotericin B
- Vancomycin & Lincomycin
- Trimethoprim
This inhibits yeast in GC-LECT
Amphotericin B
This inhibits growth of gram positive bacteria in GC-LECT
Vancomycin & Lincomycin