SEXUALLY TRANSMITTED INFECTIONS (STI)
Causes of STI
Viruses Bacteria Fungi Parasitic
Herpes Neisseria Candida Trichomonas
Papilloma Gardnerella
Chlamydia
Haemophilus
Treponema
Bacterial causes of STIs
Neisseriaceae
Neisseria
Moraxella
Kingella
Eikenella
Simonsiella
Alysiella
Nesseria
Characteristics:
Gram-negative kidney bean-shaped diplococci
Non-motile
Non-hemolytic
Oxidase positive
Aerobic with complex growth requirements
Grows best with 5% CO2
Rapidly killed by drying, sunlight, moist heat, disinfectants
Produces autolytic enzymes that result in rapid swelling and lysis in vitro at 25°C and
at an alkaline pH
Characteristics N. gonorrhea N. meningitidis
Capsule None Present
Plasmids Yes Rarely
Maltose fermentation - +
Glucose fermentaton + +
, Resist killing by the complement system
Interferes with binding with receptors on phagocytic cells
Outer membrane proteins
Por Protein I prevents phagosome-lysosome fusion
Opa Protein II adheres to heparin-related compounds, CD66 or
CEA-related adhesion molecules
Rmp Protein III associates with Por in the formation pores in the cell
surface
Other proteins
Lip (H8) – surface protein (opa)
Fbp (ferric-binding protein) – (por)
IgA1 protease
Diseases
Gonorrhea
Genital
Cervical
Gonococcal ophthalmia neonatorum
Septic arthritis
Diagnosis:
Gram-staining
Culture isolation
Serology
Nucleic acid amplification tests
Treatment:
Before 1993 Penicillin and Tetracycline
1993-2006 Fluoroquinolones
After 2006 Ceftriaxone 250 mg IM single dose or cefixime 400 mg
capsule single dose + Azithromycin 1 g orally single dose or
with 100 mg of doxycycline orally twice a day for 7 days is
recommended for possible concomitant chlamydial infections.
Present Ceftriaxone 250 mg IM single dose + Azithromycin 1 g orally
recommendation for single dose or with 100 mg of doxycycline orally twice a day
uncomplicated cervicitis, for 7 days is recommended for possible concomitant
urethritis, proctitis chlamydial infections
(CDC)
Prevention:
Chance of transmission with single exposure
Men – 20-30%
Women – higher
Prevention of multiple sexual partner
Early diagnosis (Case finding) and treatment
Mechanical prophylaxis
Crede’s prophylaxis for newborns
Klebsiella
Characteristics
Mucoid growth
With large polysaccharide capsule
Causes of STI
Viruses Bacteria Fungi Parasitic
Herpes Neisseria Candida Trichomonas
Papilloma Gardnerella
Chlamydia
Haemophilus
Treponema
Bacterial causes of STIs
Neisseriaceae
Neisseria
Moraxella
Kingella
Eikenella
Simonsiella
Alysiella
Nesseria
Characteristics:
Gram-negative kidney bean-shaped diplococci
Non-motile
Non-hemolytic
Oxidase positive
Aerobic with complex growth requirements
Grows best with 5% CO2
Rapidly killed by drying, sunlight, moist heat, disinfectants
Produces autolytic enzymes that result in rapid swelling and lysis in vitro at 25°C and
at an alkaline pH
Characteristics N. gonorrhea N. meningitidis
Capsule None Present
Plasmids Yes Rarely
Maltose fermentation - +
Glucose fermentaton + +
, Resist killing by the complement system
Interferes with binding with receptors on phagocytic cells
Outer membrane proteins
Por Protein I prevents phagosome-lysosome fusion
Opa Protein II adheres to heparin-related compounds, CD66 or
CEA-related adhesion molecules
Rmp Protein III associates with Por in the formation pores in the cell
surface
Other proteins
Lip (H8) – surface protein (opa)
Fbp (ferric-binding protein) – (por)
IgA1 protease
Diseases
Gonorrhea
Genital
Cervical
Gonococcal ophthalmia neonatorum
Septic arthritis
Diagnosis:
Gram-staining
Culture isolation
Serology
Nucleic acid amplification tests
Treatment:
Before 1993 Penicillin and Tetracycline
1993-2006 Fluoroquinolones
After 2006 Ceftriaxone 250 mg IM single dose or cefixime 400 mg
capsule single dose + Azithromycin 1 g orally single dose or
with 100 mg of doxycycline orally twice a day for 7 days is
recommended for possible concomitant chlamydial infections.
Present Ceftriaxone 250 mg IM single dose + Azithromycin 1 g orally
recommendation for single dose or with 100 mg of doxycycline orally twice a day
uncomplicated cervicitis, for 7 days is recommended for possible concomitant
urethritis, proctitis chlamydial infections
(CDC)
Prevention:
Chance of transmission with single exposure
Men – 20-30%
Women – higher
Prevention of multiple sexual partner
Early diagnosis (Case finding) and treatment
Mechanical prophylaxis
Crede’s prophylaxis for newborns
Klebsiella
Characteristics
Mucoid growth
With large polysaccharide capsule
