Chlamydia and Gonorrhea Flashcards
What is the morphology of Chlamydia spp.?
Chlamydia spp. are obligate intracellular, gram-indeterminate bacteria that lack muramic acid in their cell walls.
What are the two developmental forms of Chlamydia spp.?
Elementary bodies: Extracellular, infectious, non-replicating form.
Reticulate bodies: Intracellular, replicating form.
How are Chlamydia spp. detected in the lab?
Intracellular inclusion bodies on microscopy (visualized with Giemsa stain).
Nucleic Acid Amplification Tests (NAATs) are the gold standard for detection.
Which serovars of Chlamydia trachomatis cause STIs?
Serovars D-K and L1-L3.
What clinical features are associated with Chlamydia trachomatis serovars D-K?
Watery or mucopurulent vaginal or urethral discharge.
Pelvic inflammatory disease (PID).
Vertical transmission causing neonatal conjunctivitis or pneumonia (staccato cough).
What is lymphogranuloma venereum (LGV), and which serovars cause it?
LGV is caused by serovars L1-L3 of Chlamydia trachomatis and is characterized by tender inguinal or femoral lymphadenopathy.
What is the most common cause of infectious blindness worldwide?
Trachoma, caused by Chlamydia trachomatis serovars A-C.
How is Chlamydia trachomatis associated with reactive arthritis?
Reactive arthritis (Reiter’s syndrome) involves a triad of symptoms:
Uveitis Urethritis Arthritis
Which Chlamydia spp. are associated with atypical pneumonia?
Chlamydophila pneumoniae.
Chlamydophila psittaci (from bird feces exposure).
What is the standard treatment for Chlamydia trachomatis infections?
Macrolides (e.g., azithromycin).
Tetracyclines (e.g., doxycycline).
Why is ceftriaxone often co-administered in cases of chlamydial infection?
To treat possible Neisseria gonorrhoeae co-infection.
What is the most common bacterial STI in the U.S.?
Chlamydia (Chlamydia trachomatis).
What is the causative organism of Gonorrhea?
Neisseria gonorrhoeae, a gram-negative diplococcus.
The second most common cause of bacterial STI in the United States.
What are common risk factors for Chlamydia and Gonorrhea?
- High risk sexual activity.
- New sexual partners.
- Multiple partners.
- Inconsistent condom use.
- History of STIs.
- Men who have sex with men.
What are the clinical presentations of Chlamydia in men and women?
- Women: Cervicitis, Pelvic Inflammatory Disease (PID).
- Men: Urethritis (mucoid discharge/dysuria), and epididymitis.
- Asymptomatic: Common, especially in men.
What are the common extragenital manifestations of Gonorrhea?
- Proctitis (rectal infection).
- Pharyngitis.
- Disseminated gonococcal infection (e.g., septic arthritis, tenosynovitis).
Asymptomatic Gonorrhea is most common in men, women, or both?
Often asymptomatic in both.
What are symptoms of disseminated gonococcal infection (DGI)?
- Polyarthritis or septic arthritis.
- Tenosynovitis.
- Skin pustules.
What diagnostic test is used for Chlamydia and Gonorrhea, what do these tests have unique to them when they are positive and what does this imply?
Fluids from vaginal canal, urine, or anal/pharyngeal sites are evaluated with Nucleic Acid Amplification Test (NAAT), making them highly sensitive and specific, where false negatives and false positives are extremely rare.
What are the clinical presentations of Gonorrhea in men and women?
Men: Urethritis (mucoid discharge/dysuria), rare prostatitis or epididymitis.
Women: Urethritis, Cervicitis, Pelvic Inflammatory Disease (PID).
Asymptomatic: Common, especially in men and women.
A gram stain indicating _______ and ________ from the urethra, usually indicates a gonococcal infection.
A gram stain indicating gram-negative diplococci and PMNs from the urethra, usually indicates a gonococcal infection,
- Chlamydia does not stain, but is also treated as well. Ceftriaxone is provided to cover for Neisseria gonorrhoeae and Doxycycline is given to cover Chlamydia.
Will Chlamydia be seen on a gram stain?
No. But the NAAT test is highly sensitive and specific, a positive test requires treatment with either Azithromycin or Doxycycline to cover potential Chlamydia trachomatis co-infection (unless NAAT is negative).
Can either Chlamydia or Gonorrhea be treated individually?
Yes.
- Chlamydia can be treated with doxycycline.
- Gonorrhea can be treated with ceftriaxone.
Why are Chlamydia and Gonorrhea often treated together?
They commonly co-infect, and treating both ensures full coverage.
How is Chlamydia treated, what is the alternative treatment, particularly during pregnancy?
Doxycycline is usually the default treatment, however, amoxicillin (500 mg PO three times daily for 7 days) is a good alternative. During pregnancy, the alternative used is azithromycin (single dose of 1,000 mg).
Why is treatment and screening altered with positive Chlamydia tests during pregnancy?
Nonpregnant patients with Chlamydia trachomatis confirmed on nucleic acid amplification testing (NAAT) are typically treated with doxycycline monotherapy. However, because doxycycline is a potential teratogen, pregnant patients are treated with azithromycin. All sexual partners are also treated to prevent reinfection, and patients are advised to abstain from intercourse for 7 days following the completion of treatment. Untreated, undertreated, or recurrent chlamydial infection can lead to ascending infection into the uterine cavity. If the infection or associated inflammation compromises the amniotic sac or uterus, patients become at increased risk for obstetric complications (eg, preterm prelabor rupture of membranes, preterm labor, postpartum endometritis). In addition, vertical transmission via contact between the fetus and infected maternal discharge during delivery can result in complications, including neonatal pneumonia and neonatal conjunctivitis. Therefore, patients treated for a sexually transmitted infection during pregnancy require retesting a month after completion of treatment to ensure response to therapy (ie, test of cure). Patients with a sexually transmitted infection diagnosed earlier during pregnancy are also retested in the third trimester, prior to delivery.
What are possible complications of untreated Chlamydia or Gonorrhea in women?
Pelvic Inflammatory Disease (PID).
Infertility.
Ectopic pregnancy.
Pharyngitis.
What are possible complications of untreated Chlamydia in pregnant women?
- Preterm prelabor rupture of membranes
- Preterm labor
- Postpartum endometritis
What neonatal infections can be attributed to untreated Chlamydia in pregnant women?
- neonatal conjunctivitis
- neonatal pneumonia
Pregnant patients who are positive for Chlamydia should be retested at what point in the pregnancy?
Since vertical transmission via contact between the fetus and infected maternal discharge during delivery can result in complications, including neonatal pneumonia and neonatal conjunctivitis, patients treated for a sexually transmitted infection during pregnancy require retesting a month after completion of treatment to ensure response to therapy (ie, test of cure). Patients with a sexually transmitted infection diagnosed earlier during pregnancy are also retested in the third trimester, prior to delivery.
