What does a chlamydia infection look like?

Most infections don’t have visible signs – at least 70% of women and 50% of men who have been diagnosed have no symptoms of chlamydia at all. If chlamydia does cause visible symptoms, these differ between men and women

Visible signs in women:

• Discharge – chlamydia doesn’t normally cause signs that you can see on the skin of the vulva. Often however, there may be a change in vaginal discharge – changes are very variable, but usually there is more discharge than usual, and it may be mucousy, stringy or even blood stained, with pus. 

• Cervical inflammation and bleeding – chlamydia can cause inflammation at the cervix and cause the outer portion of the cervix to look very red, this is a condition called cervicitis. This wouldn’t be visible under normal circumstances, but would be visible if a doctor examined you. The cervix often bleeds easily, so this is something that you might notice during or after sexual activity 

• Signs of pus or swelling during a pelvic examination –  sometimes a doctor or nurse might examine you, to do this they will insert two fingers into the vagina and feels the abdomen with the other hand. This sometimes reveals tenderness within the pelvis, especially on touching or moving the cervix, or around the uterus and Fallopian tubes. There may be swelling of the tubes and ovaries, this is called a 'hydrosalpinx', or if there is pus present within the tubes, a 'pyosalpinx'

• Visible signs on other tests – in some circumstances a laparoscopy may be performed, which is a special telescopic examination of the pelvis done under an anaesthetic. Sometimes this may reveal thin, sticky strings of scar tissue, causing segments of the bowel, ovaries/tubes and pelvic tissues, to clump together. These are known as adhesions

Visible signs in men:

• Urethral discharge – (the urethra is the tube that runs up the inside of the penis). The discharge is usually clear and stringy. In a sexual health clinic, the doctor or nurse may take a specimen and look at this under the microscope. They are looking for signs of infection such as an increased amount of white blood cells, and the chlamydia bacteria

• Swollen testicles – men may develop acutely painful testes, either on one side or both – so called epididymo-orchitis. If this happens, the testes can become swollen, red and hot. This needs urgent medical attention

• During a rectal examination:

• Prostate tenderness – when a doctor or nurse inserts a finger into the rectum, may reveal an acutely tender prostate, if there is prostatitis. There may also be rectal discomfort

• Anal discharge or bleeding – if chlamydia affects the rectum it can cause symptoms of pain, discharge and bleeding. To examine the rectum, a special instrument called a proctoscope is sometimes inserted, and may show reddening of the rectal area, sometimes with discharge and bleeding. This is called proctitis, and occurs most often in men who have sex with men, often due to rectal chlamydia

Visible signs in men and women:

• Painful, red, hot, joint or joints e.g. knee joint – this can  be because of chlamydia-related arthritis

• A red sticky eye, with a discharge – chlamydia can affect the eye causing conjunctivitis

Can I compare pictures of chlamydia with my own body?

This isn’t a good way to tell if you have chlamydia – although it may be tempting to look at pictures of chlamydia on the internet and compare this to any symptoms you are suffering or clinical signs you may have, this is not recommended because:

• Most people with chlamydia have no symptoms or signs

• There are a variety of symptoms of signs that may well not be due to chlamydia

• If you guess you have chlamydia, and get it wrong, you may well be missing another serious infection or medical condition

• The internet does not always give accurate information

• You cannot visualise your own genitalia properly

What if I compare pictures and I think they match? – if you have any concerns you may have chlamydia you are strongly advised to have a chlamydia test. Remember even if you compare yourself with pictures and don’t see matching symptoms, you could still have chlamydia without visible symptoms. This is very common.

What if I don’t want to get tested? – there is no good alternative. Chlamydia is a common infection, and it is easy to have a test and be treated if it is positive. Doctors and nurses are trained to deal with these issues, and they will do their best to put you at ease.

The test is simple and painless – you can do it yourself in the toilet, without even having to get undressed in the consulting room. It’s always better to know one way or the other, and not continue to worry, possibly unnecessarily. The sooner the infection is treated if you do have it, the better the long term outcome is likely to be.

Can doctors recognise chlamydia by sight?

A doctor wouldn’t make a diagnosis based on sight – when a patient comes to the clinic and asks to be tested for chlamydia, there is no way a doctor or nurse can be sure whether or not chlamydia is present just by looking. A chlamydia test may well be positive when there is nothing abnormal to see. This is why if you have been at risk, it is so important to have a test, even if you do not feel anything is wrong.

They will examine you for symptoms though – if you have symptoms, the doctor will examine you. They need to obtain verbal consent from you to do this. You should be offered a chaperone. You can request a doctor with the gender of your choice, but you may be asked to come back another day if this cannot be accommodated there and then.

They might suspect chlamydia without testing first – if a person has risk factors, symptoms and signs suggestive of chlamydia, the doctor may look at a discharge or an inflamed cervix and have a pretty high index of suspicion that this is chlamydia. Unfortunately the only certain way to diagnose chlamydia is by having a test and waiting a few days for the result.

Sometimes, the doctor may suggest treatment before the results are known – this would only be in situations where there would be definite benefit from early treatment for a variety of reasons:

• You have severe symptoms and chlamydia is likely from the sexual history

• You are a sexual contact of someone who has recently been diagnosed with chlamydia

• Sexual assault

• Clinical diagnosis of non specific urethritis (NSU), cervicitis, or PID 

• Having an abortion

Why testing before treatment is usually recommended – it is generally not advisable to give patients antibiotics unless there is certainty they are needed. Patients can be allergic to antibiotics, get side effects, and also overusing antibiotics increases the likelihood of antibiotic resistance.

Are there other diseases that look similar to chlamydia?

Which diseases have similar visible symptoms to genital chlamydia? – chlamydia causes abnormal vaginal discharge, irregular bleeding, abdominal pain and penile discharge, so any infection which can cause these symptoms, is part of the differential diagnosis of chlamydia. Note also that it is possible to have more than one cause for symptoms, as it is possible to have more than one STI at the same time. Similar conditions include:

• Most other STIs – e.g. gonorrhoea, herpes, trichomoniasis

• Other vaginal conditions – e.g. bacterial vaginosis/candidiasis -”thrush”

• Pregnancy – and pregnancy disorders e.g. miscarriage, ectopic pregnancy

Which diseases have similar visible symptoms to anal chlamydia? – chlamydia causes inflammation in the rectum/anus, and can cause rectal pain, pain on defecation, anal discharge and bleeding. Similar conditions include:

• Piles/haemorrhoids – these are varicose veins around the anus

• Threadworms

• Inflammatory bowel disease – Crohn’s disease

• Anal/rectal cancers – uncommon

Which diseases have similar visible symptoms to eye chlamydia? – chlamydia causes a red sticky eye. However many other bacteria, and viruses an do the same thing:

• Viral conjunctivitis

• Bacterial conjunctivitis – e.g. streptococcal, staphylococcal, gonorrhoea

• Contact lens use

• Foreign body in the eye

Sources

Henricks, M. (2016). 10 essential facts about chlamydia. everydayhealth.com. [online] Available at: https://www.everydayhealth.com/sexual-health/living-with/essential-facts-about-chlamydia/ [accessed 1st June 2018].

Sexwise (2016). Chlamydia. [online] Available at: https://www.sexwise.org.uk/stis/chlamydia [accessed 4th August 2020].