Infects epithelial cells in urethra, rectum, cervix, pharynx, conjunctiva.
Most often colonises genitourinary tract and rectum
Transmission - sexual, or through vaginal delivery
Does not survive long outside human body due to sensitivity to dehydration.
Also, gene conversion and phase variation help avoid immune response and cause repeated infection
More branched than other gram-negative bacteria's lipopolysaccharide (LPS).
Targeted by IgM
OMPI and OMPIII complex together to form a porin.
OMPII - mediates attachment (along with pili).
-> also goes through antigenic variation
-> contribute to evasion of immune response
-> aka "opacity protein"
-> because it makes gonococcal colonies less translucent
A higher proportion of female infections are asymptomatic than male.
Co-infection with other STD is common
-> 10-20% male and 30-50% females has co-existing chlamydia
In males: Yellow, purulent, exudate + Painful urination
In females: Initially endocervical infection
-> Greenish-yellow cervical discharge
-> Intermenstrual bleeding
-> Can progress to uterus
In uterus, can cause:
Prevalent in male homosexual
Constipation, painful defecation, purulent discharge
Oral-genital contact.
May mimic streptococcal/virla sore throat
Conjunctivitis acquired by a newborn during vaginal delivery
If untreated -> may lead to blindness
Adult gonococcal conjunctivitis can also occur.
Bacteremia is rare (in contrast to N. meningitidis)
Can cause fever, erythematous, or maculopapular lesion in skin.
Can also cause painful purulent arthritis
-> most common cause of septic arthritis in sexually active adults
Over 20% resistant to penicillin, tetracycline, cefoxitin, and/or spectinomycin (due to penicillinase)
-> called PPNG (penicillinase-producing N. gonorrhoeae)
First line: 3rd generation cephalosporin (ceftriaxone)
May also include doxycycline to treat co-existing chlamydia infection.
Prevention of ophthalmia neonatorum - routine use of silver nitrate or erythromycin drop in eyes immediately after birth. Erythromycin is also good against chlamydia trachomatis.
Immunity - no lasting immunity
Things to revise/add later:
Bibliography: LWW microbiology
About | |
Created | 20040330 |