Infections of the genital tract

Question 1

Describe the host defences in the vaginal area, which microorganisms are an exception?

Answer 1

Vaginal epithelium contains glycogen (due to the circulating estrogens) and when certain lactobacilli colonize the vagina they metabolize the glycogen to produce lactic acid - making the vaginal pH 4-5 which inhibits colonization for microbes other than lactobacilli, certain streptococci and diphtheroids

Question 2

Name three ways lactobacilli colonize and protect the vagina from other microbes

Answer 2

It prevents other microorganisms from attaching to the epithelia by

1. producing a defensive layer over the epithelia
2. Producing lactic acid, lowering the pH
3. 60% produce hydrogen peroxide which also inhibits bacterial growth

Question 3

What is the gram and shape of lactobacilli and where are they found in the body?

Answer 3

Gram positive, rod shaped, part of normal vaginal flora

Question 4

Name five symptoms and 3 signs of a vulvovaginal candidiasis infection?

Answer 4

Symptoms:
-pruritus (itchiness), dyspareunia, dysuria, vaginal soreness, abnormal vaginal discharge - becomes “cottage cheese like” (normally watery and clear)

Signs:
Vulvar edema, fissures, thick curdy discharge

Question 5

How do other microorganisms colonize and invade the vagina?

Answer 5

1. Must have specific mechanisms for attaching to vaginal or cervical mucosa OR 2. Take advantage of minute local injuries (warts, syphilis) or
2. Impaired defences (tampons, estrogen imbalance)

Question 6

What causes vulvovaginal candidiasis?

How common is this infection and how can it be spread?

Answer 6

Candida albicans and occasionally other candida species or yeasts (opportunistic bacteria)

70% will have one infection and 40-45% will have >1

Can be spread through sexual activity, childbirth and when there are alterations to the normal vaginal pH causing a more alkaline environment or changes in normal flora (i.e during antibiotic use)

Question 7

How can vulvovaginal candidiasis be treated and what is a common symptom?

Answer 7

Antifungal agents in a cream, oral tablet or pessary

Vaginal itching/burning especially during urination.

Question 8

Why are STIs so easily spreadable

Answer 8

Many only have mild symptoms or are asymptomatic

Question 9

What five basic things should you think about when investigating someone you suspect has an STI?

Answer 9

5 Ps:

1. Partners
2. Practices
3. Prevention of pregnancy
4. Protection of STDs
5. Past history of STDs

Question 10

How are STIs spread?

Answer 10

Contact (penis, vagina, rectum, breaks in skin, mucous membranes)

And needle sharing, blood contacts, vertical transmission (mother-child)

Question 11

Name four population groups that are particularly at risk of acquiring an STI

Answer 11

1. Homosexual men
2. Sex workers
3. Older age groups
4. Younger people; about half of STI diagnosis (especially chlamydia)

Question 12

Name seven common symptoms experienced by those with an STI including three specific to the vagina

Answer 12

1. Pain during urination
2. Bumps/sores
3. Bleeding between periods - vaginal
4. Unusual discharge - vaginal
5. Pain during intercourse
6. Vulvar burning - vaginal
7. Pruritus

Question 13

Name three common bacteria, viral and parasitic STI pathogens

Answer 13

Bacterial: chlamydia, gonorrhoea, syphilis
Viral: herpes, HPV, Hep B
Parasitic: pubic lice, scabies, trichomoniasis

Question 14

What are the treatment differences between a bacterial and viral STI

Answer 14

Bacterial infections are curable but meds don’t protect against future exposure (can have multiple infections)

Viral infections are mostly not curable but can be treated/managed with meds to reduce symptoms and outbreaks

Question 15

What causes syphilis and how are they identified? How is the disease transmitted?

Answer 15

Caused by spirocytes (curved spiral bacteria), particularly treponema pallidum. The infection can’t be identified on gram staining as the organisms are too small, but can be seen by a silver stain or fluorescence techniques

Transmitted through contact (skin-skin, mucous membranes), vertical transmission

Question 16

How is syphilis treated? Is syphilis completely curable?

Answer 16

With a single IM penicillin injection unless patient is in the tertiary stage

Although syphilis is curable the damage done to the body and/or internal organs is not reversible

Question 17

Name three diseases characterized by vaginal discharge

Answer 17

Bacterial vaginosis (disease caused by excessive growth of bacteria, i.e during excessive antibiotic use), trichomoniasis, vulvovaginal candidiasis

Question 18

What causes bacterial vaginosis? Name five general things that are commonly associated with acquiring this disease and the two major symptoms experienced with it

Answer 18

Replacement of the normal H202 producing lactobacillus with excessive growth of anaerobic gram + bacteria.

Malodour and a milky discharge

Associated with; multiple partners, new sex partners, lack of condom use, douching, and lack of vaginal lactobacillus (hormonal imbalance)

Question 19

How would you treat bacterial vaginosis and what happens if it goes untreated?

Answer 19

With antibiotics (and douching can be prescribed)

If untreated the bacteria may spread to the uterus and Fallopian tubes which may progress to pelvic inflammatory disease, and transmission will continue between sex partners and newborns (increased risk of premature birth)

Question 20

Name two diseases characteristic by urethritis and cervicitis?

Answer 20

Gonococcal infections, chlamydia

Question 21

What happens to the cervix during cervicitis? Name three common symptoms and the major two organisms responsible. Are symptoms always experienced?

Answer 21

The cervix becomes edematous and hypertrophic

Symptoms: Vaginal mucopurulent discharge (yellowy, made of macrophages trying to fight the infection), deep dyspareunia, postcoital bleeding (bleeding unrelated to menstruation occurring during or after sexual intercourse). But many are asymptomatic!

C. Trachomatis (chlamydia) or N. gonorrhoea (gonorrhoea)

Question 22

Is the bacterium chlamydia trachomatis gram -/+, and which cells does it infect?

The bacterium is said to have a biphasic life cycle, what is meant by this?

Answer 22

Gram -ve. Infects columnar epithelial cells

Can have two live forms
1st phase (intracellular): small Elementary Bodies (EB) enter the cell and can indicate a new infection. Once inside, they transform into a large body with multiple initial bodies called... 

A Reticulate Body (RB), larger and once inside the cell can multiply in the cytoplasm via binary fusion. The reticulate bodies will then reorganize/convert themselves into the elementary bodies…

2nd phase (extracellular): once maturation is complete (after 2-3 days), the cell ruptures freeing elementary bodies to penetrate other cells. EBs are transmittable particles, surrounded by a rigid cell wall that allows them to divide outside the host cell.

Question 23

Why is chlamydia an ‘obligatory intracellular bacteria’?

Answer 23

It can only replicate within a host cell (which results in the host cell’s death)

Question 24

Name four symptoms experienced by men and four by women when infected with chlamydia

How common is it that men and women are asymptomatic when infected with C. trachomatis?

Answer 24

Men: epididymitis, urethritis, dysuria, penile discharge

Women: itching/burning in/around the vagina, abdominal pain with fever, painful periods, abnormal vaginal discharge (+ the 3 symptoms mentioned for cervicitis!)

50% of men have no symptoms and 80% of women

Question 25

What can happen if chlamydia goes untreated in females, what if the female is pregnant? What can happen in males?

Answer 25

Both: C. trachomatis infects and kills cells within the conjunctiva, scarring of the conjunctiva tissue can lead to permanent damage and blindness.

Males: (esp white) higher risk of arthritis

Females: Infertility (causing scar tissue in the Fallopian tubes), ectopic pregnancy, PID and erosion and erythema of the cervix (severe reproductive and health problems).

The newborn is at risk of premature birth, eye infections and blindness, pneumonia,

Question 26

What is NGU and who experiences it?

Answer 26

Nongonococcal urethritis is an infection of the urethra and/or epididymitis experienced by males

Question 27

Describe the shape and gram -/+ characteristics of N. gonorrhoea. What is its reservoir and how is it transmitted?

Answer 27

Gram -ve, is a kidney shaped diplococci. It’s reservoir is humans and it is transmitted directly through sexual contact (including birth)

Question 28

Which type of epithelial cells do the bacteria N.gonorrhoea infect in males and females and how?
*Include how they protect themselves against the host’s immune system

Answer 28

Columnar (not squamous)
Males: distal urethra, Females: cells of cervix (not vagina)

1. Has pili that attach to cells of the urethra and vagina. They can also attach to sperm cells which allow them to travel to the upper genital tract
2. The pili have IgA protease which allows it to break down the secretory IgA in the surface (of the urethra, endocervix and fallopian tubes), *surface pili also prevent phagocytosis by neutrophils to protect themselves from the host immune system
3. Once endocytosed they kill the ciliated cells which produce an inflammatory response

Question 29

What are the potential systemic complications of an N.gonorrhoea infection?

Answer 29

If engulfed by a macrophage they can take over the cell, exist within the macrophage and disseminate dormant throughout the body; causing a disseminated gonococcal infection which may lead to…

1. Arthritis or tenosynovitis: if it collects in the synovial fluid
2. Dermatitis
3. Polyarthralgia
4. Meningitis
5. Endocarditis

Question 30

In which gender are gonococcal infections more common and which three organs are involved?

Answer 30

Females; infections of pharynx, urethra and cervix

Question 31

Who is particularly at risk of a disseminated gonococcal infection?

Answer 31

Patients with congenital deficiency of C7, C8 and C9

Question 32

Describe the onset of symptoms in both males and females during a gonococcal infection

How common is it that men and women are asymptomatic when infected with N.gonorrhea?

Answer 32

Males: symptoms appear 2-7 days as urethritis - frequency, penile purulent discharge, penile swelling and redness. 10% have no symptoms

Women: Can include dysuria, vaginal discharge, bleeding between periods BUT most will only present with PID or when they’re having difficulty conceiving. Nearly 50% have no symptoms

Question 33

Where is the primary site of urogenital infections in women? What other gland is commonly affected and what can happen as a result of this?

Answer 33

The endocervical canal is the primary site but the Bartholin’s gland duct is also commonly infected (secondary to nonspecific inflammation or trauma) resulting in a cyst.

The cyst is usually asymptomatic (unilateral, tense and non painful) but can dilate to cause an abscess; which can cause necrosis of the area (if blood supply is cut off)

Question 34

Name four signs of a classic abscess

Answer 34

Erythema, acute tenderness, oedema and occasionally cellulitis (inflammation of surrounding subcutaneous tissue)

Question 35

When and how would you treat a Bartholin’s gland cyst?

Answer 35

Only treat a symptomatic cyst. The classical surgical treatment is to develop a fistulous tract to “marsupialize” the duct

Question 36

What kind of swab would you take if you suspected a gonorrhea vs chlamydia infection? Other than swabs, how else can you attain a specimen?

Answer 36

If chlamydia suspected: take cervical and urethral swabs
If gonorrhea suspected: take vulvovaginal swabs and endocervical swabs
Can also use first-catch urine specimen

Question 37

What are some neonatal complications of gonorrhoea?

Answer 37

Eye issues (easy as its a mucous membrane), disseminated gonococcal infections, scalp abscess

Question 38

What can a NAAT test determine, and how could you collect a specimen to preform one on?

Answer 38

The NAAT test (nucleic acid amplification testing) detects the genetic material/nucleic acid of the bacteria by amplifying it so the detection system can identify the bacterias’ presence. It can be done after a swab or urine sample (preferably urine for men)

Question 39

What is tenosynovitis and what does it typically lead to?

Answer 39

Inflammation of the fluid-filled sheath (synovium) surrounding tendons. Typically leads to joint pain, swelling, stiffness

Question 40

Which three organs are most likely to be involved in fibrosis in congenital syphilis? What is the typical morphology of congenital syphilis in the brain?

Answer 40

Fibrosis most commonly occurs in the liver, pancreas and lungs (but can be present in multiple organs).

Brain: chronic meningitis

Question 41

What is a Tubo ovarian abscess and how does one form? What is the major complication that may occur?

Answer 41

A confined ‘pocket of pus’ that forms during an infection of a fallopian tube and ovary, and is one of the late complications of pelvic inflammatory disease. It can be life-threatening if the abscess ruptures and results in sepsis.

Question 42

Which three infectious diseases are screened for in pregnancy?
*note; this does not nearly include all of the infections that may cause congenital defects or miscarriages

Answer 42

1. HIV
2. Hep B
3. Syphilis

Question 43

What causes PID and what is the major complication that can result from this syndrome?

Answer 43

Pelvic inflammatory disease is caused by the ascension of microorganisms from the cervix and vagina into the upper genital tract, can lead to permanent damage of a woman’s reproductive organs (including infertility)

Question 44

Pathogenic Neisseria are capable of changing surface antigens using 3 highly efficient mechanisms, what are they?

Answer 44

1. Mutating individual amino acids
2. Phase variation: switching genes on and off
3. Horizontal exchange of DNA material

Question 45

How is chlamydia transmitted and how does it enter the body? Which cancer is associated with this disease?

Answer 45

Breaches in the mucus membrane, the infected epithelial cells trigger a vigorous immune response which increases the risk of cervical cancer.

Question 46

Where do LGV strains of chlamydia infect?

Answer 46

lymph nodes in the groin causing boboes and genital sores

Question 47

How is chlamydia diagnosed and treated?

What would be given to treat a pregnant woman with chlamydia?

Answer 47

Diagnosed: test penal or vaginal secretions or urine with ELISA, DFA (direct fluorescent antibody test), chlamydia cultures and nucleic acid amplification

Treated with two antibiotics, if pregnant the woman is given erythromycin with amoxicillin