Coxiella burnetii: Difference between revisions

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===Treatment===
===Treatment===
'''*Acute Q fever'''
'''*Acute Q fever''' <ref>{{cite web | title =q fever | url = http://www.cdc.gov/mmwr/preview/mmwrhtml/rr6203a1.htm  }}</ref>
:* Adults:
:* Adults:
::*Preferred Regimen: [[Doxycycline]]PO 100 mg bid for 14 days
::*Preferred Regimen: [[Doxycycline]]PO 100 mg bid for 14 days
Line 52: Line 52:
::* Note: childern and pregnant women- consultation  Recommended
::* Note: childern and pregnant women- consultation  Recommended


Postpartumwith serologic profile for chronic Q fever
:*Postpartumwith serologic profile for chronic Q fever
:::* Preferred regimen:[[Doxycycline]] PO 100 mg bid and [[hydroxychloroquine]] PO  200 mg tid for 12 months
::* Preferred regimen:[[Doxycycline]] PO 100 mg bid and [[hydroxychloroquine]] PO  200 mg tid for 12 months
::*Note: Women should only be treated postpartum if serologic titers remain elevated >12 months after delivery (immunoglobulin G phase I titer ≥1:1024). Women treated during pregnancy for acute Q fever should be monitored similarly to other patients who are at high risk for progression to chronic disease (e.g., serologic monitoring at 3, 6, 12, 18, and 24 months after delivery)
::*Note: Women should only be treated postpartum if serologic titers remain elevated >12 months after delivery (immunoglobulin G phase I titer ≥1:1024). Women treated during pregnancy for acute Q fever should be monitored similarly to other patients who are at high risk for progression to chronic disease (e.g., serologic monitoring at 3, 6, 12, 18, and 24 months after delivery)



Revision as of 15:16, 25 June 2015

Coxiella burnetii
C. burnetii, the causative agent of Q fever
C. burnetii, the causative agent of Q fever
Scientific classification
Kingdom: Bacteria
Phylum: Proteobacteria
Class: Gamma Proteobacteria
Order: Legionellales
Family: Coxiellaceae
Genus: Coxiella
Species: C. burnetii
Binomial name
Coxiella burnetii
(Derrick 1939)
Philip 1948

Coxiella burnetii is a species of intracellular, pathogenic bacteria, and is the causative agent of Q fever. The genus Coxiella is morphologically similar to the rickettsia, but with a variety of genetic and physiological differences. C. burnetii are small Gram negative bacteria with two growth phases, as well as a spore form which lies idle in soil.[1] It can survive standard disinfectants, and is resistant to many other environmental changes.[2]

Pathogenesis

The ID50 (the dose needed to infect 50% of experimental subjects) is one via inhalation— i.e. inhalation of one organism will yield disease in 50% of the population. Disease occurs in two states: An acute state presents with headaches, chills, and respiratory symptoms, and an insidious chronic stage.

While most infections clear up spontaneously, treatment with tetracycline or doxycycline appears to reduce the symptomatic duration and reduce the likelihood of chronic infection. A combination of erythromycin and rifampin is highly effective in curing and prevention of disease and so is vaccination with Q-vax vaccine (CSL).


Treatment

*Acute Q fever [3]

  • Adults:
  • Preferred Regimen: DoxycyclinePO 100 mg bid for 14 days
  • Children
  • Children with age ≥8 years:
  • Preferred regimen:Doxycycline PO 2.2 mg/kg per dose bid for 14 days (maximum 100 mg per dose)
  • children with age <8 years with high risk criteria
  • Preferred regimen:Doxycycline PO 2.2 mg/kg per dose bid for 14 days (maximum: 100 mg per dose)
  • children with age <8 years with mild or uncomplicated illness:
  • Preferred regimen:Doxycycline PO 2.2 mg/kg per dose bid for 5 days (maximum 100 mg per dose). If patient remains febrile past 5 days of treatment: Trimethoprim/Sulfamethoxazole 4-20 mg/kg bid for 14 days (maximum: 800 mg per dose)
  • Pregnant women


Chronic Q fever

  • Endocarditis or vascular infection
  • Preferred regimen:Doxycycline PO 100 mg bid and hydroxychloroquine PO 200 mg tid for ≥18 months
  • Note: childern and pregnant women- consultation Recommended
  • Noncardiac organ disease
  • Postpartumwith serologic profile for chronic Q fever
  • Preferred regimen:Doxycycline PO 100 mg bid and hydroxychloroquine PO 200 mg tid for 12 months
  • Note: Women should only be treated postpartum if serologic titers remain elevated >12 months after delivery (immunoglobulin G phase I titer ≥1:1024). Women treated during pregnancy for acute Q fever should be monitored similarly to other patients who are at high risk for progression to chronic disease (e.g., serologic monitoring at 3, 6, 12, 18, and 24 months after delivery)


  • Note:Post-Q fever fatigue syndrome- no current recommendation

References

  1. Ryan KJ; Ray CG (editors) (2004). Sherris Medical Microbiology (4th ed. ed.). McGraw Hill. ISBN 0-8385-8529-9.
  2. Sankaran, Neeraja (2000). "Coxiella burnetii". Microbes and people : an A-Z of microorganisms in our lives. Phoenix, Arizona: The Oryx Press. p. 72. ISBN 1-57356-217-3. "In contrast to other rickettsiae, which are highly sensitive and easily killed by chemical disinfectants and changes in their surroundings, C. burnetii is highly resistant" & "Q fever". Centers for Disease Control and Prevention; National Center for Infectious Diseases; Division of Viral and Rickettsial Diseases; Viral and Rickettsial Zoonoses Branch. 2003-02013. Retrieved 2006-05-24. Check date values in: |date= (help) "The organisms are resistant to heat, drying, and many common disinfectants."
  3. "q fever".