BACTE LEC NEISSERIA Flashcards
Aerobic, non-motile, non spore forming, gram-
negative diplococci
Most of Neisseria spp.
The rod shaped neisseria spp.
N. weaveri, N. Elongata, N. Bacilliformis
Neisseria spp. are known to be __________ positive and ____________________ positive
Catalase, Cytochrome Oxidase
What type of bacteria are Neisseria spp. based on carbon dioxide requirement
Capnophilic
N. meningitidis may be found as a commensal inhabitant of the ______________________ of carriers, but it can also become an invasive pathogen
Upper respiratory tract
Pathogenic Neisseria spp. are ______________ organisms, requiring enriched media for optimal recovery
fastidious
What are the pathogenic neisseria spp
N. gonorrheae
N. meningitidis
N. weaveri
what specific element is needed for the fastidious N. gonorrheae and N. meningitidis
Iron
The primary reason why pathogenic Neisseria spp. are strictly human pathogens
The ability to bind transferrin
N. weaveri can be found as a commensal in the ___________________ of the dog
upper respiratory tract of the dog
What are the virulence factors of the pathogenic Neisseria spp.
- Receptors for human transferrin
- Capsule (N. meningitidis)
- Pili
- Cell membrane proteins
- Lipooligosaccharides
- IgA protease
primary virulence factor of N.gonorrheae
Pili (fimbriae)
3 Cell membrane proteins in Pathogenic Neisseria spp.
Por (Protein II)
Opa (Protein III)
Reduction modified protein (protein III)
channel for passage of nutrients
and waste products
Por (Protein II)
facilitate adherence of
organisms to phagocytic and epithelial cells
Opa (protein II)
blocks host IgG
Reduction modified protein (protein III)
protective against host’s inflammatory
response and complement mediated killing
PorB expressed only by N.gonorrheae
acute pyogenic
infection of the non-ciliated columnar and transitional
epithelium
gonorrhoea
Causative agent of gonorrhea
Neisseria gonorrheae
gonorrhea is also known as the _______
clap
primary resevoir of Neisseria gonorrheae
asymptomatic carrier
Neisseria gonorrheae incubation period
2-7 days
symptoms of men that have gonorrhea
purulent discharge and dysuria
how many cases are asymptomatic for men
3-5% of cases
common site of infection of N. gonorrhea is the _____________
endocervix
symptoms of women that have gonorrhea
cervical discharge, dysuria, & lower abdominal pain
common strain of Neisseria gonorrheae in men
AHU strain
what are the sources of specimen for Neisseria gonorrheae
Urethra for men
Endocervix for women
Rectum
Pharynx
joint fluid
In men: when no apparent discharge, swab is inserted up to _____ in the anterior urethra and
slowly rotated to collect the discharge
2cm
Swab for rectal culture should be inserted __________ into
the anal canal
4-5cm
____________ swabs are preferred for Neisseria gonorrheae
4-5cm
o Gonococcal eye infection
o Acquired during delivery through an infected
birth canal
o Can lead to blindness
Opthalmia neonatorum
Commercial Transport systems for N. gonorrheae must contain _________________ and _______________________
selective media and CO2 atmosphere
examples of Commercial Transport systems for N. gonorrheae
o JEMBEC plates (James E. Martin Biological
Environmental Chamber)
o Gono-Pak
o Transgrow
N. gonorrheae Smears are prepared from __________________________
urogenital specimens
Nasopharyngeal specimens not recommended for identifying N. gonorrheae from gram stain due to the presence of ___________________________
commensal Neisseria
N. gonorrheae does not grow on ___________, instead the ideal medium to be used is _______________
BAP, CAP
___________________ is used to prevent the growth of swarming proteus spp. in the N. gonorrheae plate
Trimethoprim
N. gonorrheae palte is examined for growth after___________ days
7
N. gonorrheae Colonies are _______________________________ and ___________
after __________ of incubation
small, gray to tan, translucent, raised
24-48 hours
colony of N. gonorrheae that are piliated, and considered as virulent colonies
T1 and T2
colony of N. gonorrheae that are non piliated and avirulent
T3-T5
_____________________ is recommended for workup since the
organism can produce their own autolytic enzyme
Fresh culture
Colonies are streaked to a plate with __________________
10 unit
penicillin disk
Oxidase Test Reagents
o 1% dimethyl p-phenylenediamine
dihydrochloride
o 1% tetramethyl p-phenylenediamine
dihydrochloride
Presumptive biochemical test positive result?
Purple color within 2 seconds
What are the inhibitory agents for Thayer Martin
Vancomycin, Colistin, Nystatin
What are the inhibitory agents for Modified Thayer Martin
Vancomycin, Colistin, Nystatin, Trimethroprim
What are the inhibitory agents for Martin Lewis
Vancomycin, Colistin, Anisomycin, Trimethroprim
What are the inhibitory agents for New York medium
Vancomycin, Colistin, , Trimethroprim, Amphotericin B
Cystine Trypticase Agar, yellow color in the medium as a result of
fermentation
carbohydrate Utilization test
- Based on color changes after bacterial enzymes
hydrolyse the CHO substrates - Useful for identification of N.gonorrheae
Chromogenic Substrates Methods of CHO utilization
- Combine substrates of other biochemical tests
- Can also identify other genera such as Haemophilus
spp.
Multitest Method
- Microbial proteins are separated based on size and
charge - Detects unique protein signatures of the organisms
MALDI-TOF MS
Detects gonococcal antigens or nucleic acids directly
from specimens
Non-Culture methods
Can be a commensal in the upper tract
Neisseria meningitidis
- Causative agent of: meningitis and meningococcemia
- Recovered from urogenital and rectal sites due to
oral-genital contact - MOT: close contact of infection person via respiratory
droplets
Neisseria meningitidis
_________________________ using CTA medium
* Medium: Cystine Trypticase Agar
o pH indicator: Phenol red
o 1% of individual CHO
▪ Glucose
▪ Maltose
▪ Sucrose
▪ Lactose
* Result: yellow color in the medium as a result of
fermentation
* N.gonorrheae: N.gonorrheae: Ferments glucose
Carbohydrate Utilization Test
Causative agent of: meningitis and meningococcemia
* Recovered from urogenital and rectal sites due to oral-genital contact
* MOT: close contact of infection person via respiratory
droplets
Neisseria meningitidis
Purpura (hemorrhaging of blood into the skin and mucous membranes
producing bruises) with petechial skin rash
Meningococcemia
Abrupt onset of frontal head ache,
neck stiffness, confusion, and photobia
Meningitidis
Incubation: ______________________
1-10days
4 Fulminant form of meningococcemia
o DIC
o Septic Shock
o Waterhouse-Friderichsen Syndrome -
hemorrhage in the adrenal gland
o Rash - endotoxins
Cultured on BAP and CAP (especially from specimens
containing normal microbiota)
* Does not require X and V factor
- Opportunistic pathogen
- Cause of upper RT infection in healthy adults and
children - May cause lower RT infection on persons with COPD
- 3rd most common cause of acute otitis media and
sinusitis in children
- Opportunistic pathogen
- Cause of upper RT infection in healthy adults and
children - May cause lower RT infection on persons with COPD
- 3rd most common cause of acute otitis media and
sinusitis in children
Moraxella catarrhalis is a positive for ________________________
beta lactamase
Colonies described as “__________” - remains intact when pushed across the plate with a loop
hockey puck
Tests to Differentiate From Neisseria
- Grows on NA
- DNAse positive
- Fails to utilize CHO in the CTA medium
- Butyrate esterase reaction + (Tributyrin as the
substrate)
