Neisseria gonorrhoeae

Occurrence, Resevoir, MOT, IP

• Gonorrhea (Clap, PID)
• Occ: Worldwide- 1 million cases/yr. reported to CDC (Real #s are 3-4x as high)
• Dies quickly outside host
• 60% cases in 15-24 year age bracket b/c of high-risk sexual behaviors
• Res: Humans
• MOT: direct contact (STD/venereal infection), (neonatorium)
• IP: 2-8 days before onset of SX (5-20% are asymptomatic); In 7-21 days will have mild SX (50% asymptomatic)

Neisseria gonorrhoeae

SN/SX

• Acute infection of any mucous membrane: mainly genital-urinary tract, eye, rectum,pharynx
• Bacteria attach by pili & invade epithelial cells, therefore, it is an INTRACELLULAR PARASITE; hard for host defenses to defeat
• Gleet: yellow, creamy urethral discharge with frequent dysuria
• In males without TX, get inflammation of epididymis & testes- results in sterility.
• In females without TX, infection of Skene's and Bartholin's glands more often Endocervical Glands & spreads to endometrium; abdominal pain bilateral; purulent cervical, NOT vaginal discharge.

• PID: pelvic inflammatory disease; fever, chills, rebound pain (push abdomen down then let up); may also be caused by Chlamydia (45% are coinfected)
• DGI: Disseminated Gonococcal Infection; spreads from primary site of infection via blood to another site (1-3% GU infection). Often asymptomatic at primary site. Most often causes arthritis-dermatitis sydrome of knees, ankles, & wrists; may cause meningitis or endocarditis
• Opthalmia Neonatorium: conjunctivitis in newborn can lead to blindness (most common cause of blindness if not treated).

Neisseria gonorrhoeae

DX, TX

• DX: stained smears of exudates (gram (-) diplococcus) from urethra; culture methods (Transgrow Agar)
• RX: PCN-G (IM) 1 dose (amoxicillin or ampicillin OK also); Tetracyclines if PCN sensitive for 7 days (patient may not comply). PPNG = PCNase-producing N. gonorrhoeae (1981) resistant strain; In 1985 tetracycline resistant strains appeared in US; New cephalosporins available that work
• TX for Opthalmia Neonatorium: Crede's Method 1% AgNO3 (Silver Nitrate) won't kill Chlamydia infection of eye. A triple antibiotic ointment is added prophy in case of coinfection.
• No immunity.

Neisseria meningitidis

Meningococcal Septicemia

• Infection of blood by N. meningitidis
• SN/SX: fever, arthritis, extensive skin rash (purpura) & bilateral destruction of adrenal cortex= Lethal; Worst case scenario: Waterhouse-Friderichsen Syndrome, rapidly fatal 25% of time; spreads to blood as nasopharyngeal infection

Neisseria meningitidis

Meningococcal Meningitis

• Inflammation of meninges of CNS
• SN/SX: causes epidemic bacterial meningitis
• 2nd most common cause of bacterial meningitis (27%)
• CFR is high
• Survivors suffer major sequelae (defects): deafness, mental retardation, behavior defects

Neisseria meningitidis

TX & Immunity

• Res: nasopharynx of asymptomatic carrier
• TX: PCN, chloramphenicol if PCN resistant; Rifampin prophy if exposed but not sick
• Immunity: Vaccine available but immunity doesn't last long
• Epidemics occur when large numbers of people are crowded toether (military, schools, day cares); Army & Navy recruits receive vaccine for serogroup C. 

• Numerous diseases
• Gram (-) coccus, non-motile, OBLIGATE INTRACELLULAR PARASITE
• 15 serotypes:
• A-C = trachoma
• D-K = inclusion conjunctivitis
• L = lymphogranuloma venereum

Chlamydia trachomatis

Trachoma

• Most common single cause of blindness worldwide
• One of the oldest known infectious diseases of humans
• Severe conjunctivitis, scars cornea resulting in blindness
• 400 million infected worldwide, 20 million blinded
• Under age 20 female/male ratio = 3:1 (babies)
• Spreads by contact with fingers, soap, towels, etc. also flies

Chlamydia trachomatis

Inclusion conjunctivitis

• Copious mucous discharge from eye
• Bacterium has large inclusion bodies, which are granules of glycogen in cytoplasm
• Occurs in neonate 7-10 days postpartum
• Infection occurs from contamination of eyes passing through birth canal
• May cause pneumonia (very serious)

Chlamydia trachomatis

Lymphogranuloma venereum (LGV)

• An STD common in the tropics, US 300 cases/yr.
• Primary phase: small ulcer appears several weeks after inoculation (on penis for males, on labia or vagina for females); heals w/o scarring
• Secondary phase: 2-4 weeks after ulcer, Bubo(es) (swollen lymph nodes) appear in inguinal region; fever, chills, anorexia
• Late phase: occurs only if secondary phase not TX; Urethral or rectal constrictures, poor lymph drainage b/c of the granulomatous-type connective tissue that causes the lymph nodes to swell. NO TX!
• TX for other phases: tetracyclines

Chlamydia trachomatis

Non-Gonococcal Urethritis (NGU)

• Most common STD in US (10 million cases/yr.
• 50% NGU caused by Chlamydia trachomatis; Also caused by Candida (yeast), Herpes (virus), Trichomonas (protozoan), Mycoplasma (wall-less bacterium)
• Males usually asymptomatic, but can have discharge & urethral strictures
• Causes PID in females, if pregnant it is very bad on fetus: abortion, still born, inclusion conjunctivitis, pneumonia

• Causes respiratory illness that may lead to asthma
• May be associated with cardiovascular disease (CVD) such as atherosclerosis (build-up in lumen, restricts blood flow) & arteriosclerosis (hardening of the arteries)