Chlamydia. T

A sexually transmitted infection that is caused by the bacteria Chlamydia trachomatis. It can be categorised by uncomplicated- not affecting the upper genital tract and complicated- infection has spread to the upper genital tract. It is spread through sex or contact with infected genital fluids eg. semen, vaginal fluid.

Epidemiology

According to the NICE guidelines in 2018 and 2019, studies found in the UK that the rate of diagnosis was highest in age groups 15-24 years old
Chlamydia is the most common bacterial sexually transmitted infection according to the WHO
There was an estimated 127 million new cases of chlamydia in 2016 recorded by the WHO [1]
According to the Centre of Disease Control, 1 in 20 sexually active young women aged 14-24 years has chlamydia
Studies found that the risk of transmission of infection from one episode of sexual intercourse is approx 10-20% [2]

Pathophysiology [3]

Medical Student
- Chlamydia trachomatis are gram-negative anaerobic bacteria that multiple inside eukaryotic cells (membrane bound nuclei).
- The bacteria targets the squamocolumnal epithelial cells of the endocervix, upper genital tract in women and rectum and urethra in men and women.
- Chlamydia has two forms in the body, elementary and reticulate bodies.
- Elementary bodies are chemically/metabolically inactive; once it enters the cell, it becomes active and turns into a reticulate body.
- Reticulate bodies replicate by using nutrients of the host cell.
- This in turn, leads to the reticulate bodies to form more elementary bodies in order to infect more cells.
- The excessive production of elementary bodies leads to the bursting of the cell and consequently causes it to die.
- This process continues and leads to further cell death.
Patients
- Chlamydia trachomatis is a bacteria that doesn’t require oxygen that multiple inside complex cells known as eukaryocyte cells.
- The bacteria targets specific cells that is a junction between the squamous epithelium cells and the columnar epithelium cells. They are found in the endocervix (inner part of the cervix), upper genital tract in women and rectum and urethra in men and women.
- Chlamydia has two forms in the body, elementary and reticulate bodies.
- Elementary bodies are chemically inactive- meaning it enters the cell without impacting it.
- Once it enters the cell, it becomes active and turns into a reticulate body.
- Reticulate bodies replicate by using nutrients of the host cell.
- This in turn, leads to the reticulate bodies to form more elementary bodies in order to infect more cells.
- The excessive production of elementary bodies leads to the bursting of the cell and consequently causes it to die.
- This process continues and leads to further cell death.

Source: SOA Amsterdam

Chlamydia trachomatis
Watery penile discharge in males

Causes

Unprotected vaginal, anal or oral sex
Sharing sex toys that are not cleaned or covered before use
Contact between genitals
Infected bodily fluids like semen or vaginal fluid getting into the eye
Can be passed from pregnant woman to foetus
Prevention can include using condoms and being in a relationship with one partner who has been tested for chlamydia [4,5]

Risk factors
- Younger age (under 25)
- Non-white patients hold a higher risk according to 10 of 23 studies in females and one of four studies in males
- Having multiple partners increasing the likelihood of pathogen exposure
- Failure to use contraceptive devices and barriers eg condoms
- Primarily spread through penetrative sex [1,6]
Presentations
- Most people don’t notice any symptoms
- Symptoms usually appear between 1-3 weeks after unprotected sex and can disappear after a few days
- Symptoms in women
  - At least 70% don’t experience symptoms
  - Pain when urinating
  - Vaginal discharge (unusual patterns)
  - Pain in the stomach/pelvis
  - Pain during sex
  - Bleeding post coital (after sex)
  - Bleeding between period
  - Can lead to pelvic inflammatory disease- increasing the risk of ectopic pregnancy and infertility
  - Burning during urination
- Symptoms in women
  - At least 50% don’t experience symptoms
  - Pain when urinating
  - White, cloudy discharge from the tip of the penis
  - Testicular pain
  - Burning or itching in the tube that carries urine out of the body (urethra)
  - Can cause welling of the epididymis (tube carrying sperm from the testicles)
  - Can lead to affected fertility
- Other symptoms
- Discomfort or discharge from the rectum (back passage)
- Can impact the throat but often presents with no symptoms
- Redness, pain and discharge in the eyes [4,7]

Investigations [4]

Nucleic acid amplification testing is preferred as it has a higher level of sensitivity (ability to accurately diagnose positive results)
- Can be obtained from urine samples or vaginal swabs
- Results normally available in 7 to 10 days (UK)
- May be required to repeat testing if inital test was done before 2 weeks post exposre due to diagnosis potentially not being made in the early stages
In England, it is recommended under the National Chlamydia Screening Programme that under 25 year old men and women are tested once a year and sexually active without barrier protection (eg condoms) or after intercourse with new partners.

Differential diagnosis [1]
- Other sexually transmitted infections:
  - Bacterial vaginosis
  - Gonorrhoea
  - Vaginal candidiasis (fungal)
  - Trichomonas vaginitis
- Pelvic inflammatory disease
- Urinary tract infection

Management [8]

Medical Student
- Doxycycline is the treatment of choice for urogenital chlamydia in adolescents and adults. This is used for 7 days.
- A single oral dose of Azithromycin is alternatively used as treatment for those who cannot tolerate doxycyclin, such as pregnant women.
- Abstinence is necessary until more than 1 week after treatment and partners must be treated too.
- In pregnant women- early intervention such as screening as well as treatment is needed to prevent neonatal chlamydial infections such as conjunctivitis.
Patients
- The drug of choice to prevent the growth of bacteria such as Chlamydia is Doxycycline. This is used for chlamydia affecting the genital and urinary organs in the body amongst adolescents and adults. This is used for 7 days.
- A single oral dose of Azithromycin is alternatively used as treatment for those who cannot tolerate doxycyclin, such as pregnant women.
- Abstinence (no sex) is necessary until more than 1 week after treatment and partners must be treated too.
- In pregnant women- early intervention such as screening as well as treatment is needed to prevent neonatal chlamydial infections (pregnant women with chlamydia can pass the infection onto their feotus) such as conjunctivitis.

Source: SOA Amsterdam

Cervix inflammation (cervicitis) caused by chlamydia found during a pap smear (test to check the cervix)

Complications [4]
- Pelvic inflammatory disease once the chlamydia spreads to the womb, ovaries or fallopian tubes (female genital organs)
- Infertility
- Increased risk of ectopic pregnancy (egg implanted outside the womb)
- Pelvic pain
- Can spread infection to feotus in pregnant women
- Inflammation of the testicles due to spread of infection to testicles and epididymis
- Reactive arthtitis due to chlamydia causing inflamation of the joints
  - https://www.nhs.uk/conditions/chlamydia/complications/
Myths

Only women get chlamydia
Chlamydia is self resolving
It can only be spread through vaginal intercourse
You can get chlamydia from surfaces eg toilets
Chlamydia also shows symptoms
You can only get chlamydia if you have multiple partners
Chlamydia is difficult to treat
Chlamydia only affects people once [9,10]

Questions you may want to ask your doctor
- How do I know if I have chlamydia if I don’t present with symptoms?
- When can I have sex again after treatment?
- What can I do to protect myself if I have sex with multiple partners?
- What tests need to be done to test for chlamydia?
- How long does treatment last?
- How can I let my partner(s) know I have chlamydia?
- Who should I contact if I suspect that the infection has spread?
Support
- Centers for Disease Control and Prevention
- Terrence Higgins Trust
- WHO.int