Chapter 20- Neisseriae Flashcards
human pathogen that is associated with or inside polymorphonuclear cells
Neisseria meningitidis (meningococci)
Gram-negative, nonmotile diplococcus, 0.8 um kidney-bean shaped
Typical Neisseria
In what hour does gonococci and meningicocci form convex, glistening, elevated mucoid 1-5 mm in diameter
48 hours
Describe colonies of a typical Neisseria
Transparent or opaque, nonpigmented and non-hemolytic
Nesseria species that produces yellow pigment
N.flavescens
N. subflava
N. cineria
N. lactamica
Nesseria sp that produces opaque, brittle, wrinkled colonies
N.sicca
produces nonpigmented or pinkish gray opaque colonies
Moraxella catarrhalis
Nesseria species that oxidizes glucose
N. gonorrhea N. meningitidis N. lactamica N. sicca N. subflava N. mucosa N. polysaccharea
Nesseria species that oxidizes maltose
N. meningitidis N. lactamica N. sicca N. subflava N. mucosa N. polysaccharea
Nesseria species that oxidizes lactose
N. lactamica
Nesseria species that oxidizes sucrose
N. sicca
N. subflava
N. mucosa
Nesseria species that has DNAse
Moraxella catarrhalis
Media where meningococci and gonococci grows best
On organic substances Heated blood Hemin Animal proteins 5% CO2
Growth of meningococci and gonococci is inhibited by
Fatty acids and salts
meningococci and gonococci are rapidly killed by
drying
sunlight
moist heat
disinfectants
Gonococci require these products in order to grow
Arginine
Hypoxanthine
Uracil
Colonies of gonococci in selective subculture
Small colonies with piliated bacteria
Colonies of gonococci in nonselective subculture
Larger colonies with non-piliated gonococci
Antigenic structure of N.gonorrhea
- Pili (Fimbrae)
- Por
- Opa proteins
- Rmp (Protein III)
- Lipooligosaccharide
- Lip (H8)
- Fbp (ferric-binding protein)
- IgA1 protease
Antigenic structure of N.gonorrhea that enhance attachment to host cells and resistance to phagocytosis
Pili (fimbriae)
Antigenic structure of N.gonorrhea that prevents phagosome-lysosome fusion
Por proteins
Antigenic structure of N.gonorrhea that function in adhesion within colonies and their attachment to host cell receptors
Opa proteins
Antigenic structure of N.gonorrhea that is associated with Por in the formation of pores in the cell surface
Rmp (Protein III)
Antigenic structure of N.gonorrhea that helps them evade immune recognition of the host cell
Lipooligosaccharide
Antigenic structure of N.gonorrhea that is a surface-exposed protein that is heat modifiable like Opa.
Lip (H8)
Antigenic structure of N.gonorrhea that is similar in MW to Por that is expressed when the iron supply is limited
Ferric-binding protein (Fbp)
Antigenic structure of N.gonorrhea that splits and inactivates IgA1
IgA1 protease
Por proteins selectively bind to what complement
C3b and C4b
Opaque gonococci colonies is associated with?
Men with SYMPTOMATIC urethritis
Uterine cervical cultures at midcycle
Transparent gonococci colonies is associated with
ASYMPTOMATIC urethral infection in men
Menstruating women
Patients with invasive form of gonorrhea
Treatment prevention for gonococcal ophthalmia neonatarum (SET)
silver nitrate
erythromycin
tetracycline
Specimes for diagnostic lab tests for N.gonorrheae
Pus
Secretions
Synovial fluid
Blood culture
Tests for gonococcal smears in women
NAATs or cultures
Media best for gonococci
Modified Thayer-Martin medium (MTM) 5% CO2 at 37 C
To avoid overgrowth of gonococci, selective medium must contain (T-VAC)
Trimethoprim (3 ug/mL)
Vancomycin (3 ug/mL)
Amphotericin B (1 ug/mL)
Colistin (7.5 ug/mL)
_____ hours after culture, gonococci that can identified by gram-stained smear
48 hours
Gonococci can be identified through
Oxidase positive
Coagglutination
Immunofloresence
Test for direct detection of N.gonorrhea
NAATs
Antibodies present against gonococcal pili, outer membrane proteins and LPS
IgA
IgG
IgM
Antibodies against gonococcal pili, and outer membrane proteins are detected by
Immunoblotting
Radioimmunoassay
ELISA
Treatment for gonococcal infections
IM ceftriaxone 250 mg
Oral cefixime 400 mg
Treatment for gonococcal infections with concomitant chlamydial infections
1 g Azithromycin or
100 mg of Doxycycline oral for 7 days
Treatment for gonococcal ophthalmia neonatarum
0.5% erythromycin ophthalmic ointment
1 % tetracycline ointment for conjunctiva
Most important serogroups of N.meningitidis that are associated with human disease
A, B, C, X, Y and W-135
Meningococcal antigens are found in
Blood and CSF
The outer membrane of N.meningitidis contains these things that plays a role in their virulence
Proteins and LPS
Responsible for toxic effects of meningococcal disease
Lipid A disaccharide of meningococcal LPS
Portal on entry of N.meningitidis
Nasopharynx
Meningococci are readily phagocytosed in the presence of
Specific opsonin
Specimens used for diagnostic lab tests for meningococci
NP swab culture
Puncture material from petechiae
Culture media for N. meningitidis
CSF on chocolate agar at 37 C 5% CO2
Drug of choice for N. meningitidis
Pen G
Drug for N. meningitidis that is allergic to Pen G
Chloramphenicol
3rd Gen Cephalosporins (Cefotaxime or ceftriaxone
M.catarrhalis produces this enzyme that forms the basis for rapid fluorometric tests
Butyrate esterase
