Neisseria gonorrhoeae

Question 1

transmission route of neissaeria gonorrhoeae

Answer 1

sexual contant via secretions of the genital tract

Question 2

structural advantages of Neisseria gonorrhoeae

Answer 2

type IV pili - attachment to epithelial cells

polysaccharide capsules - preventing the recognition and phagocytosis by macrophages and neutrophils
+ facilitating colonisation on surfaces

lipooligosaccharide (LOS) (Lipid A + oligosaccharide chain) – stimulates the release of pro-inflammatory cytokines
+ structural variations evade recognition from immune cells

Question 3

type IV pili

Answer 3

attachment to epithelial cells

Question 4

polysaccharide capsules

Answer 4

protective barrier against the host immune system, preventing the recognition and phagocytosis by macrophages and neutrophils
+ facilitating colonization on surfaces

Question 5

lipooligosaccharide (LOS)

Answer 5

(Lipid A + oligosaccharide chain) – activator of the host immune response – stimulates the release of pro-inflammatory cytokines
+ structural variations evade recognition from immune cells

Lipid A is an endotoxin that exacerbates tissue damage by stimulating pro-inflam cytokines

+ adhesion to host cell

Question 6

Lipid A endotoxin -

Answer 6

potent stimulator of the immune system and inflammatory response

triggers release of pro-inflam cytokines such as IL-1, IL-6 and TNFa

chronic inflammation can proliferate the infection, exacerbating tissue damage

may lead to fever, septic shock, and organ failure

Question 7

what Proteases and Enzymes does N. gonorrhoeae produce?

Answer 7

IgA1 Protease
endonuclease NucA
Endonucleases
superoxide dismutase (SOD) and catalase.
Beta-lactamases

Question 8

IgA1 Protease

Answer 8

cleaves IgA1 antibodies found in mucosal secretions
evades immune response at mucosal surfaces of the genital tract

Question 8

endonuclease NucA

Answer 8

encoded by the nucA
cleaves both strands in DNA
allowing it to degrade NETs
NETs = web-like structures composed of DNA, histones, and antimicrobial proteins released by neutrophils to trap and kill pathogens

Question 9

what are the infection rates of gonorrhoea between men and women if had contact with infected individual

Answer 9

men 20%
women 50%

Question 10

what is the difference in symptoms between men and women?

Answer 10

women - often asymptomatic
may develop Pelvic inflammatory disease (leads to scarring, ectopic pregnancy, infertility)​

men - Acute inflammation​
- Dysuria (painful urination)​
- Purulent (pus-filed) discharge from urethra/rectum​
- Pharyngeal infection​
- Ascending infection​

Question 11

describe the ability of N. gonorrhoea to Immunomodulate the macrophage

Answer 11

after a macrophage endulfs the bacteria cell, it can:

&Escapes the phagosome​&
– creates a membrane rupture by releasing degadation enzymes from the Type IV Secretion System (T4SS) on the membrane surface
– avoiding lysosomal degradation

&Inhibits apoptosis/autophagy​&

&Modulates production of cytokines​&
– such as interleukin-12 (IL-12) and tumor necrosis factor-alpha (TNF-alpha)

&Modulates iron production from the macrophages​&

&Reduces capability of T cell proliferation&​

Question 12

describe the damaged caused by N. gonorrhoea

Answer 12

Infects mucus-secreting epithelial cells in men and women​
Disrupts epithelial integrity​
Loss of ciliated cells​
Fallopian tube scarring​
Occlusion of the oviduct​
Adhesions = chronic pelvic pain​​

Urethritis​
Systemic dissemination​

Question 13

what are the complications of neonatal gonorrhoea?

Answer 13

severe cornea or conjunctiva​ infections leading to potential blindness
respiratory infections such as pneumonia and sepsis.

Question 14

describe antibiotic resistance in Neisseria gonorrhoeae ——-

Answer 14

innate resistance factors from being gram Neg

Question 15

What is the Gonococcal resistance to antimicrobial surveillance programme (GRASP)?

Answer 15

national sentinel surveillance programme established in 2000 to monitor trends and drifts in susceptibility to antimicrobial agents used for the treatment of gonorrhoea in England and Wales​

Question 16

Explain how GC VCAT (Gonococcal Culture with Vancomycin, Colistin, Anisomycin, and Trimethoprim) is used to diagnose gonorrhea

Answer 16

selective culture medium for Neisseria gonorrhoeae
Base medium - provides nutrients for growth

Vancomyacin - inhibits growth of gram pos by preventing cell wall synthesis

Colistin - is a polypeptide antibiotic that disrupts the integrity of the outer membrane of Gram-negative bacteria, making them more susceptible to other antibiotic

Anisomycin - protein synthesis inhibitor - inhibits the growth of many Gram-positive and Gram-negative bacteria

Trimethoprim - dihydrofolate reductase inhibitor that interferes with folate metabolism in bacteria – suppress growth of contaminating bacteria

Neisseria gonorrhoeae colonies appear small, grey/white, translucent