STIs And Gonorrhoeae Flashcards
Core sti groups
High prevalence of sti
High rate of partner change
Multiple concurrent partners
Dense sexual networks
Bridging population
Moderate prevalence of stis
Ie clients of sex workers drug users
Drives sporadic transmission in general population
Initial spread of stis are determined by
Rate of sexual exposure to infectious ppl
Efficiency of transmission per exposure
Duration of infectivity of those infected
Syndromic approach
Patients are managed based on the presenting symptoms and sighs and risk factors
Management of stis
Establish presence of urethritis (gram stained smear of discharge) should have more than 5neutrophils per 1000x field
Smear will have gram - intracellular diplococci (gonococcal infx)
Evaluate for complications or other diagnosis
Evaluate for gonococcal and chlamydial infx
Neisseria
2 types meningitidis and gonorrhoea
Human only host
Aerobic gram negative diplococci
N gonorrhea
Sexually transmitted
Primary infests urogenital tract
Gram negative, nonmotile, monococci or diplococci with flat sides
Second most common sexually transmitted disease
Enhances transmission of hiv bc of damaged epithelium
Has 3-4 genome copies per coccal unit (polyploidy) so increases antigenic variation and survival
N meningitidis
Nervous and attacks on CNS
N gonorrhoea affect on babies
Will have orogastric and oropharyngeal colonization
2-48% of exposed infants not given prophylaxis will develop ophthalmia neonatorum
Transmission of gonorrhoea
40-60% transmission
More efficient from male to female
Clinical presentation of gonorrhea
Urethritis pee pain Cervicitis Proctitis rectum inflammation Pharyngitis Conjunctivitis
Gonorrhoeae outer membrane antigens
Los has endotoxins activity
Ops binds host cell CEACAMs to start invasion
PorB resists bactericidal effect of serum
Pilus mediates attachment and contributes to antigenic virulence and variation
IgA protease inactivated igA on the mucosal surface
Opa
Important in adherence
Porins a b
PorA Silent in gonorrhea but active in meningitidis
PorB most abundant
Prevents complement mediated serum killing and protects bacteria
Interferes w phagosome lysozyme fusion m prevents neutrophils from causing damage
PorB1A genotypic resistance, promotes epithelial cell invasion
Host factors for gonorrhoea
Complement deficiencies c5-c9
Thus results in recurrent infections
IgA proteases cleave heavy chain of human IgA. Helps gonorrhea overcome mucosal immunity
Detection of neisseriae
By th17 cells macrophages n dendritic cells via tlr n nlr
Infection promotes il8 il16 tnf il1-beta
These activate and recruit neutrophils that adhere to vessels
Gonorrhea pathogenesis
Sexual contact
Established in urogenial tract w nonciliated epithelial cells
Infx leads to inflammation and pmn(polymorphonuclear) n macrophage influx
Toxic damage to ciliated epithelial cells by
Tnf from phagocytes
Gonococcal products (los, peptidoglycan)
Clinical manifestations G in males
Incubation period 2-7days
Acute urethritis
Major manifestations in symptomatic men:
Purulent urethral discharge (thick yellow pus)
Dysuria (painful urination)
Clinical manifestations of G in females
Mucopurulent cervicitis - infected columnar epithelium of cervix becomes reddened, friable w/ purulent discharge
Asymptomatic urethritis is more common
Symptoms develop within 10 days
Usually Lower abdominal discomfort
Painful intercourse
Both symptomatic and asymptomatic transmit infx
Abnormal bleeding
PID
Pelvic inflammatory disease
Caused by gonorrhoea
Polymicrobial infx of upper genital tract
Also caused by trachomatis cmv tb
May result in sterility
Can cause abscesses in Fallopian tubes or ovaries or peritoneum
Abortions
Gonococcal conjunctivitis
Incubation time 3-19 days
Treat w parenteral antibiotics
Characterized by hyperpurulent discharge (fountain of pus)
Can lead to blindness in 24hrs
Ophthalmia neonatrium
Range 1-5days
Swelling and purulent drainage
Severe redness n swelling of conjunctiva
Treatment is systemic and local antibiotics
Lab diagnosis of G
Inoculate immediately bc dry up very quickly
Grow in chocolate agar
Gram stain is not sensitive for women or in pharynx
Treatment for G
Treat simultaneously for chlamydia
W azithromycin or docycline
Evaluate for other stis
Treat the partner as well
