Chlamydia trachomatis: Difference between revisions
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Chlamydia trachomatis
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===Microbiology=== |
===Microbiology=== |
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− | *Small, obligate intracellular [[Stain::Gram-negative]] [[ |
+ | *Small, obligate intracellular [[Stain::Gram-negative]] [[Shape::coccobacillus]] |
**Very difficult to Gram stain due to lack of peptidoglycan in cell wall |
**Very difficult to Gram stain due to lack of peptidoglycan in cell wall |
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*Two forms exist: |
*Two forms exist: |
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===Pediatric Infections=== |
===Pediatric Infections=== |
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+ | *Serovars associated with STIs can also cause: |
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− | *[[Conjunctivitis]] in neonates |
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+ | **[[Conjunctivitis]] in neonates |
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− | *Pneumonia in children under 6 months of age |
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+ | **Pneumonia in children under 6 months of age |
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+ | |||
+ | ===Trachoma=== |
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+ | |||
+ | *Chronic [[keratoconjunctivitis]] caused by recurrent infection |
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+ | *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]] |
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+ | *Presents with two phases: |
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+ | **Active trachoma, with acute, mild, self-limited [[conjunctivitis]] |
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+ | ***May be asymptomatic |
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+ | ***Usually detected with screening |
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+ | **Cicatricial disease causing conjunctival scarring |
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+ | ***Scar tissue distorts the eyelid margin, causing entropion (the eyelid turned inwards) |
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+ | ***Entropion causes trichiasis, where the eyelashes rub against the eye and cause scarring |
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+ | ***Eventually leads to blindness |
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==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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==Management== |
==Management== |
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+ | === Adults === |
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− | *Non-pregnant, non-lactating adults with urethral, endocervical, rectal, or conjunctival infection |
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+ | |||
− | **First-line: [[Is treated by::doxycycline]] 100 mg PO bid for 7 days |
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+ | * Non-pregnant, non-lactating adults with urethral, endocervical, rectal, or conjunctival infection |
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− | **Alternative if adherence likely to be poor: [[azithromycin]] 1 g PO once |
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+ | |||
− | **Alternative: [[ofloxacin]] 300 mg PO bid for 7 days |
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+ | *First-line: [[Is treated by::doxycycline]] 100 mg PO bid for 7 days |
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+ | **Preferred, especially for rectal infection |
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+ | *Alternative if adherence likely to be poor: [[azithromycin]] 1 g PO once |
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+ | *Alternative: [[ofloxacin]] 300 mg PO bid for 7 days |
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+ | *Alternative: [[erythromycin]] 2 g/day PO in divided doses for 7 days |
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+ | *Alternative: [[erythromycin]] 1 g/day PO in divided doses for 14 days |
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+ | |||
+ | === Children === |
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+ | *Consider child abuse when chlamydia is diagnosed in a prepubertal child |
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+ | **However, perinatal infection can persist for up to 3 years |
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+ | *≤7 days old |
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+ | **Infants ≤2 kg: [[erythromycin]] 20 mg/kg/day PO in divided doses for 14+ days |
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+ | **Infants >2 kg: [[erythromycin]] 30 mg/kg/day PO in divided doses for 14+ days |
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+ | *8 days to 1 month old: [[erythromycin]] 40 mg/kg/day PO in divided doses for 14+ days |
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+ | *1 month to 9 years: [[azithromycin]] 12-15 mg/kg (max 1 g) PO once |
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+ | **Alternative: [[erythromycin]] 40 mg/kg/day PO in divided doses (max 500 mg qid for 7 days or 250 mg qid for 14 days) |
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+ | **Alternative: [[sulfamethoxazole]] 75 mg/kg/day PO in divided doses (max 1 g bid) for 10 days |
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+ | *9-18 years: [[doxycycline]] 2.5 mg/kg (max 100 mg) PO bid for 7 days |
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+ | **Alternative, if adherence likely to be poor: [[azithromycin]] 12-15 mg/kg (max 1 g) PO once |
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+ | **Alternative: [[erythromycin]] 40 mg/kg/day PO in divided doses (max 500 mg qid for 7 days or 250 mg qid for 14 days) |
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+ | **Alternative: [[sulfamethoxazole]] 75 mg/kg/day PO in divided doses (max 1 g bid) for 10 days |
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+ | |||
+ | === Pregnant or Nursing Women === |
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+ | |||
+ | * Pregnant and nursing women with urethral, endocervical, and rectal infections |
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+ | |||
+ | *[[Azithromycin]] is generally considered safe for this purpose, while [[doxycycline]] and [[fluoroquinolones]] are contraindicated |
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+ | *Options include any of: |
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+ | **Alternative: [[amoxicillin]] 500 mg PO tid for 7 days |
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**Alternative: [[erythromycin]] 2 g/day PO in divided doses 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: [[erythromycin]] 1 g/day PO in divided doses for 14 days |
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+ | **Alternative if adherence is likely to be poor: [[azithromycin]] 1 g PO once |
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− | *Children |
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+ | *Ensure that exposed neonates are tested shortly after birth and treated if positive, with monitoring for development of conjunctivitis or pneumonia |
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− | **Consider child abuse when chlamydia is diagnosed in a prepubertal child |
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+ | |||
− | ***However, perinatal infection can persist for up to 3 years |
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+ | === Lymphogranuloma Venereum === |
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− | **≤7 days old |
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+ | |||
− | ***Infants ≤2 kg: [[erythromycin]] 20 mg/kg/day PO in divided doses for 14+ days |
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+ | * [[doxycycline]] 100 mg PO bid for 21 days (see [[Lymphogranuloma venereum#Management|LGV-specific page]] for details) |
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− | ***Infants >2 kg: [[erythromycin]] 30 mg/kg/day PO in divided doses for 14+ days |
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+ | |||
− | **8 days to 1 month old: [[erythromycin]] 40 mg/kg/day PO in divided doses for 14+ days |
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+ | === Trachoma === |
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− | **1 month to 9 years: [[azithromycin]] 12-15 mg/kg (max 1 g) PO once |
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+ | *Usually addressed in mass drug administration projects using [[azithromycin]] or topical [[tetracycline]] |
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− | ***Alternative: [[erythromycin]] 40 mg/kg/day PO in divided doses (max 500 mg qid for 7 days or 250 mg qid for 14 days) |
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+ | *Often needs surgery to correct trichiasis |
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− | ***Alternative: [[sulfamethoxazole]] 75 mg/kg/day PO in divided doses (max 1 g bid) for 10 days |
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+ | |||
− | **9-18 years: [[doxycycline]] 2.5 mg/kg (max 100 mg) PO bid for 7 days |
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+ | === Treatment Failure === |
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− | ***Alternative, if adherence likely to be poor: [[azithromycin]] 12-15 mg/kg (max 1 g) PO once |
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+ | |||
− | ***Alternative: [[erythromycin]] 40 mg/kg/day PO in divided doses (max 500 mg qid for 7 days or 250 mg qid for 14 days) |
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+ | * Reinfection (most common) |
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− | ***Alternative: [[sulfamethoxazole]] 75 mg/kg/day PO in divided doses (max 1 g bid) for 10 days |
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+ | * Non-adherence |
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− | *Pregnant and nursing women with urethral, endocervical, and rectal infections |
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+ | * Vomiting |
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− | **[[Azithromycin]] is generally considered safe for this purpose, while [[doxycycline]] and [[fluoroquinolones]] are contraindicated |
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+ | * True resistance, though it is rare and difficult to assess susceptibility |
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− | **Options include any of: |
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+ | |||
− | ***Alternative: [[amoxicillin]] 500 mg PO tid for 7 days |
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+ | ==Prevention== |
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− | ***Alternative: [[erythromycin]] 2 g/day PO in divided doses for 7 days |
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+ | |||
− | ***Alternative: [[erythromycin]] 1 g/day PO in divided doses for 14 days |
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+ | ===Trachoma=== |
||
− | ***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 [[Lymphogranuloma venereum#Management|LGV-specific page]] for details) |
||
+ | *Mass drug administration using [[azithromycin]] for communities with high prevalence |
||
+ | *Facial cleanliness |
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+ | *Improved sanitation and hygiene |
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{{DISPLAYTITLE:''Chlamydia trachomatis''}} |
{{DISPLAYTITLE:''Chlamydia trachomatis''}} |
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[[Category:Bacteria]] |
[[Category:Bacteria]] |
Latest revision as of 21:00, 21 December 2021
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
Adults
- Non-pregnant, non-lactating adults with urethral, endocervical, rectal, or conjunctival infection
- First-line: doxycycline 100 mg PO bid for 7 days
- Preferred, especially for rectal infection
- 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
Pregnant or Nursing Women
- 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
Treatment Failure
- Reinfection (most common)
- Non-adherence
- Vomiting
- True resistance, though it is rare and difficult to assess susceptibility
Prevention
Trachoma
- Mass drug administration using azithromycin for communities with high prevalence
- Facial cleanliness
- Improved sanitation and hygiene