Chlamydia trachomatis infection: Clinical sciences

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Introduction0:00–0:58

Chlamydia trachomatis is the most common bacterial sexually transmitted infection, and it’s a mandatory reportable infection as a public health measure.
It can affect multiple anatomic sites, most commonly the urethra and cervix, but also the eyes, oropharynx, and rectum. Chlamydia is often asymptomatic, resulting in a large reservoir of untreated infections.
These infections can lead to pelvic inflammatory disease and increase the risk of infertility, ectopic pregnancy, and chronic pelvic pain.
Additionally, chlamydia during pregnancy also increases the risk of prelabor rupture of membranes, preterm labor, and low birth weight infants, and transmission to the neonate may cause conjunctivitis, called ophthalmia neonatorum, and pneumonia.
Your first step in evaluating a patient who presents with a chief concern suggesting Chlamydia trachomatis infection is a focused history and physical exam.

Biologically male0:58–4:26

Let’s start with biologically male patients. Since chlamydia is a sexually transmitted infection, or STI, a complete sexual history is important including questions about new partners and both oral and anal intercourse.
A private, confidential discussion is important for all patients, including young patients like adolescents. Although it can be difficult, you should ask caregivers of young patients to step out of the room for this discussion.
Additionally, whenever a young patient has a positive sexual activity history, always consider sexual assault or abuse, especially if the patient is a child.
If there is abuse going on, you will need to follow up with allegations of abuse in accordance with your State’s law.Once sexual history is complete, you can move on to signs and symptoms.
Patients may report symptoms at various anatomic sites. They may have a sore, itchy throat or difficulty swallowing.
Or they may report genitourinary symptoms such as lower abdominal pain, dysuria, pyuria, and testicular pain or swelling.
Lastly, anal and rectal symptoms include painful bowel movements or rectal spotting.Here is a high-yield fact! The majority of chlamydia infections are asymptomatic.
Therefore, screening is recommended for high-risk populations, such as sexually active women under the age of 25 and men who have sex with men.
Now back to our physical exam. The findings here might also vary based on the anatomic site.
So, you might find signs of conjunctivitis, such as erythema of the conjunctiva, swelling of the eyelid, or purulent ocular discharge.
Next, pharyngitis presents as an erythematous throat and cervical lymphadenopathy. Then, urethritis may present with a mucoid or watery urethral discharge.
Some patients might report signs of epididymitis including unilateral swelling and tenderness of a testicle, as well as lower abdominal tenderness.
Prostatitis presents with a firm, tender, and edematous prostate on digital rectal exam. Lastly, proctitis may present with swollen, tender, and erythematous rectal mucosa.
If you see any of these signs in sexually active individuals, you should suspect chlamydia trachomatis infection.And here is another high-yield fact!
Even though patients most commonly present with some of these signs, in some rare cases you might see patients with genital ulcers caused by chlamydia.
In fact, three strains of chlamydia, called serotypes L1, L2, and L3, can cause lymphogranuloma venereum, which is an uncommon but invasive genital ulcer disease that can lead to lymphadenopathy and proctocolitis.
Keep in mind that these are different from the serotypes that cause genitourinary infections, which are types D to K, and those that infect conjunctival cells and can lead to blindness, which are serotypes A to C.Alright, if you suspect chlamydia trachomatis infection, the next step is a nucleic acid amplification test, or NAAT, for chlamydia.

Biologically male - Diagnosis4:26–5:06

Although historically culture was used for diagnosis, culture is rarely performed today. Rather, NAATs are used for screening and diagnosis.
Sexual history, symptoms, and physical exam findings guide testing sites. You can swab the affected area, which can include the eye, throat, urethral meatus, or rectum.
First-void urine can also be sent to diagnose urogenital infections.Okay, let’s talk about some results. First of all, if the NAAT is negative, consider an alternative diagnosis.

Biologically male - Management5:06–6:48

On the other hand, If the NAAT is positive, you have made your diagnosis of chlamydia trachomatis infection. Treat the patient with an antibiotic, such as doxycycline.
To ensure compliance, treat patients on-site or refer to an STI clinic for same-day treatment. After administering antibiotics to your patient, be sure to refer all sexual partners for evaluation and treatment as well.
Counsel patients to abstain from intercourse until 7 days following completion of treatment. Additionally, they should abstain from intercourse until symptoms have resolved and all partners are treated.
Now, patients with any STI are logically at risk of other STIs. So, remember to perform additional STI testing to screen these patients for HIV, gonorrhea, and syphilis.
Men who have sex with men who are HIV-negative should be offered HIV pre-exposure prophylaxis, or PrEP, to reduce the risk of acquiring HIV.
Finally, retest all patients 12 weeks after treatment, because there’s a high prevalence of chlamydia among patients who have previously tested positive, largely due to reinfection.
Here is a clinical pearl. If sexual partners cannot access services for evaluation and treatment, consider expedited partner therapy, or EPT, where permitted by law.
EPT allows treating sexual partners with prescriptions or medications without examining them first. Now that we are done treating biologically male patients, let’s move on to biologically female patients.

Biologically female6:48–8:36

Again, start with a confidential sexual history including questions about new partners and anal, oral, or vaginal intercourse.
As before, patients may report physical symptoms of a sore itchy throat and difficulty swallowing, pelvic pain, dysuria, or pyuria.
They may also have symptoms of abnormal vaginal discharge, non-menstrual vaginal spotting, and post-coital bleeding. As with biologically male patients, the physical exam may reveal evidence of conjunctivitis, pharyngitis, cervical lymphadenopathy, and lower abdominal pain.
In addition, patients may present with urethritis, as well as signs of cervicitis, which includes mucopurulent discharge, cervical edema, and cervical friability.
Signs of proctitis, such as inflamed rectal mucosa can be present as well.Time for one more high-yield fact! Reactive arthritis, formerly called Reiter syndrome, is an uncommon but significant clinical syndrome related to chlamydia infections.
The classic symptoms include conjunctivitis and uveitis, urethritis, and lower-extremity arthritis typically involving one knee.
An easy mnemonic to remember signs of reactive arthritis is that they can’t see, can’t pee, and can’t climb a tree. This condition usually resolves within 5 months but some patients develop chronic arthritis.

Biologically female - Diagnosis8:36–9:15

Now, if you suspect Chlamydia trachomatis infection, the very first step in a biologically female patient is to get labs like an HCG pregnancy test; followed by a NAAT for chlamydia.
A swab can be performed at the affected sites such as the eye, throat, cervix, urethra, or rectum. First-catch urine can also be obtained for the diagnosis of urethral and cervical infections.
However, keep in mind that the most accurate approach is either patient self-collected or provider collected swab of the infected area.Alright, let’s talk about the results.

Biologically female - Management9:15–11:43

If the NAAT is negative for Chlamydia, consider an alternative diagnosis. However, if the NAAT is positive, you have made your diagnosis of Chlamydia trachomatis.
Next, assess for pregnancy with the HCG test you obtained previously. This is important because you might need to choose different antibiotics.
If the patient has a negative HCG pregnancy test, initiate treatment with an antibiotic, such as doxycycline for 7 days or azithromycin once.
Remember to refer all partners for testing and treatment and to consider expedited partner therapy. Counsel patients to abstain from intercourse until 7 days after completion of treatment, until symptoms have resolved and all partners have been treated.
Perform additional STI testing for HIV, gonorrhea, and syphilis. Again, repeat chlamydia testing at 12 weeks after treatment to assess for possible reinfection.
Okay, let’s move on to pregnant patients with a positive HCG pregnancy test. First treat them with an antibiotic that’s safe in pregnancy, like azithromycin.
Again, refer partners for testing and treatment; counsel patients to abstain from intercourse; and perform additional STI testing for HIV, gonorrhea, and syphilis, as with non-pregnant patients.But it’s not all the same, here’s the catch!
Chlamydia infection is a significant risk factor for prelabor rupture of membranes, preterm delivery, and low birth weight infants.
It can also cause neonatal conjunctivitis and pneumonia. That’s why for neonatal safety, you should perform a test of cure in 4 weeks, retest in 12 weeks, and again in the third trimester.
Keep in mind that screening for Chlamydia at the first prenatal visit is recommended for all pregnant patients.And one last clinical pearl!
If a patient with chlamydia trachomatis infection has an IUD in place, the IUD doesn’t need to be removed as part of the management plan.
However, patients with current purulent cervicitis or chlamydial infection with no IUD in place should not undergo IUD insertion until being treated first.Alright, as a quick recap… Chlamydia trachomatis is a bacterial STI that’s often asymptomatic, and can affect multiple anatomic sites, most commonly the urethra and cervix, but also the eyes, oropharynx, and rectum.

Review11:43–12:45

Patients with Chlamydia infection may present with symptoms like itchy throat and difficulty swallowing, pelvic pain, dysuria, and mucopurulent discharge, and should be evaluated with NAAT testing.
Treat all non-pregnant patients with antibiotics like doxycycline, and pregnant patients with antibiotics that are safe in pregnancy like azithromycin.
In addition for both patients, refer partners for testing and treatment; counsel patients to abstain from intercourse; and perform additional STI testing.
Lastly, retest non-pregnant patients 12 weeks after initial treatment. As for pregnant patients, perform a test of cure at 4 weeks, and repeat testing at 12 weeks and in