Chlamydia trachomatis: Difference between revisions
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Chlamydia trachomatis
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**Pneumonia in children under 6 months of age |
**Pneumonia in children under 6 months of age |
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+ | ===Trachoma=== |
− | * |
+ | *Chronic [[keratoconjunctivitis]] caused by recurrent infection |
− | * |
+ | *Leading infectious cause of blindness worldwide |
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+ | *Spread via direct contact of ocular or nasal secretions and via fomites, and possibly via eye-seeking flies including [[Musca sorbens]] |
− | * |
+ | *Presents with two phases: |
− | ** |
+ | **Active trachoma, with acute, mild, self-limited [[conjunctivitis]] |
− | *** |
+ | ***May be asymptomatic |
− | *** |
+ | ***Usually detected with screening |
− | ** |
+ | **Cicatricial disease causing conjunctival scarring |
− | *** |
+ | ***Scar tissue distorts the eyelid margin, causing entropion (the eyelid turned inwards) |
− | *** |
+ | ***Entropion causes trichiasis, where the eyelashes rub against the eye and cause scarring |
− | *** |
+ | ***Eventually leads to blindness |
==Diagnosis== |
==Diagnosis== |
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*Culture |
*Culture |
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**For throat specimens |
**For throat specimens |
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+ | **Done in cell culture |
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*Serology |
*Serology |
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**IgM antibodies can be helpful for diagnosting pneumonia in infants under 3 months of age |
**IgM antibodies can be helpful for diagnosting pneumonia in infants under 3 months of age |
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**Often needs surgery to correct trichiasis |
**Often needs surgery to correct trichiasis |
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− | == |
+ | ==Prevention== |
− | === |
+ | ===Trachoma=== |
− | * |
+ | *Mass drug administration using [[azithromycin]] for communities with high prevalence |
− | * |
+ | *Facial cleanliness |
− | * |
+ | *Improved sanitation and hygiene |
{{DISPLAYTITLE:''Chlamydia trachomatis''}} |
{{DISPLAYTITLE:''Chlamydia trachomatis''}} |
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[[Category:Bacteria]] |
[[Category:Bacteria]] |
Revision as of 11:47, 3 December 2020
Background
Microbiology
- Small, obligate intracellular Gram-negative coccobacillus
- Very difficult to Gram stain due to lack of peptidoglycan in cell wall
- Two forms exist:
- Elementary body (EB): spore-like form than can survive short times outside the body
- Reticulate body (RB): replicative form
- Virulence factors include lipopolysaccharide (LPS)
Risk Factors
- Sexual contact with chlamydia-infected person
- New sexual partner, or more than two sexual partners in the past year
- Previous STI
- Specific populations: people who inject drugs, incarcerated people, sex trade workers, street-living youth
Clinical Manifestations
- Incubation period is 2 to 3 weeks (Incubation period range::1 to 6 weeks)
- Many are asymptomatic
- Presentation varies by serovar
Serovars | Syndromes |
---|---|
A to C | Trachoma (chronic conjunctivitis) |
D to K | Urethritis, PID, neonatal infection |
L1 to L3 | Lymphogranuloma venereum (LGV) |
Sexually-Transmitted Infection
- In men, most are symptomatic
- Incubation period is 7 to 21 days in men
- Purulent urethritis, urethral itch, dysuria, testicular pain
- Conjunctivitis
- Proctitis (often asymptomatic)
- Sequelae include epididymo-orchitis and reactive arthritis
- In women, often asymptomatic
- Cervicitis, vaginal discharge, dysuria, lower abdominal pain, abnormal vaginal bleeding, dyspareunia
- Conjunctivitis
- Proctitis (often asymptomatic)
- Sequelae include pelvic inflammatory disease, ectopic pregnancy, infertility, chronic pelvic pain, and reactive arthritis
Lymphogranuloma Venereum
Fitz-Hugh-Curtis syndrome
- Liver capsular inflammation, possibly autoimmune
Pediatric Infections
- Serovars associated with STIs can also cause:
- Conjunctivitis in neonates
- Pneumonia in children under 6 months of age
Trachoma
- Chronic keratoconjunctivitis caused by recurrent infection
- Leading infectious cause of blindness worldwide
- Spread via direct contact of ocular or nasal secretions and via fomites, and possibly via eye-seeking flies including Musca sorbens
- Presents with two phases:
- Active trachoma, with acute, mild, self-limited conjunctivitis
- May be asymptomatic
- Usually detected with screening
- Cicatricial disease causing conjunctival scarring
- Scar tissue distorts the eyelid margin, causing entropion (the eyelid turned inwards)
- Entropion causes trichiasis, where the eyelashes rub against the eye and cause scarring
- Eventually leads to blindness
- Active trachoma, with acute, mild, self-limited conjunctivitis
Diagnosis
- Molecular testing
- Urine NAAT is ~80% sensitive, and is preferred when there is no other indication for a pelvic examination
- Self-collected vaginal swab likely has better sensitivity, though
- MD-collected cervical swab best sensitivity (90+%)
- Culture
- For throat specimens
- Done in cell culture
- Serology
- IgM antibodies can be helpful for diagnosting pneumonia in infants under 3 months of age
- Not helpful for diagnosing genital infections
Management
- Non-pregnant, non-lactating adults with urethral, endocervical, rectal, or conjunctival infection
- First-line: doxycycline 100 mg PO bid for 7 days
- Alternative if adherence likely to be poor: azithromycin 1 g PO once
- Alternative: ofloxacin 300 mg PO bid for 7 days
- Alternative: erythromycin 2 g/day PO in divided doses for 7 days
- Alternative: erythromycin 1 g/day PO in divided doses for 14 days
- Children
- Consider child abuse when chlamydia is diagnosed in a prepubertal child
- However, perinatal infection can persist for up to 3 years
- ≤7 days old
- Infants ≤2 kg: erythromycin 20 mg/kg/day PO in divided doses for 14+ days
- Infants >2 kg: erythromycin 30 mg/kg/day PO in divided doses for 14+ days
- 8 days to 1 month old: erythromycin 40 mg/kg/day PO in divided doses for 14+ days
- 1 month to 9 years: azithromycin 12-15 mg/kg (max 1 g) PO once
- Alternative: erythromycin 40 mg/kg/day PO in divided doses (max 500 mg qid for 7 days or 250 mg qid for 14 days)
- Alternative: sulfamethoxazole 75 mg/kg/day PO in divided doses (max 1 g bid) for 10 days
- 9-18 years: doxycycline 2.5 mg/kg (max 100 mg) PO bid for 7 days
- Alternative, if adherence likely to be poor: azithromycin 12-15 mg/kg (max 1 g) PO once
- Alternative: erythromycin 40 mg/kg/day PO in divided doses (max 500 mg qid for 7 days or 250 mg qid for 14 days)
- Alternative: sulfamethoxazole 75 mg/kg/day PO in divided doses (max 1 g bid) for 10 days
- Consider child abuse when chlamydia is diagnosed in a prepubertal child
- Pregnant and nursing women with urethral, endocervical, and rectal infections
- Azithromycin is generally considered safe for this purpose, while doxycycline and fluoroquinolones are contraindicated
- Options include any of:
- Alternative: amoxicillin 500 mg PO tid for 7 days
- Alternative: erythromycin 2 g/day PO in divided doses for 7 days
- Alternative: erythromycin 1 g/day PO in divided doses for 14 days
- Alternative if adherence is likely to be poor: azithromycin 1 g PO once
- Ensure that exposed neonates are tested shortly after birth and treated if positive, with monitoring for development of conjunctivitis or pneumonia
- Lymphogranuloma venereum: doxycycline 100 mg PO bid for 21 days (see LGV-specific page for details)
- Trachoma:
- Usually addressed in mass drug administration projects using azithromycin or topical tetracycline
- Often needs surgery to correct trichiasis
Prevention
Trachoma
- Mass drug administration using azithromycin for communities with high prevalence
- Facial cleanliness
- Improved sanitation and hygiene