Difference between revisions of "Ehrlichiosis"

(added leukopenia...)
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==Background==
 
==Background==
*Bacterial infection of the family Anaplasmataceae
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*Bacterial infection of the family Anaplasmataceae common in mammals such as cattle, dogs, sheep, goats, and horses<ref>CDC. Ehrlichiosis. http://www.cdc.gov/ehrlichiosis.</re>
*Spread by the Lonestar tick (Amblyomma americanum)
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*Spread by the Lonestar tick (Amblyomma americanum) [[File:Lone Star Tick.jpg|thumb|Lone Star Tick (preserved]]
 
**Eastern seaboard from Florida to Maine and as far west as Iowa and Texas
 
**Eastern seaboard from Florida to Maine and as far west as Iowa and Texas
**People often unaware they are bitten
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**People often unaware they are bitten with case fatality rate of approximately 1.8%<ref>CDC http://www.cdc.gov/ehrlichiosis/stats/</ref>
*Case fatality rate is approximately 1.8%
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**More severe disease in immunocompromised patients ([[HIV]], Elderly, '''Asplenic''')
**More severe disease in immunocompromised patients (HIV, Elderly, '''Asplenic''')
 
  
 
==Symptoms==
 
==Symptoms==
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==Diagnosis==
 
==Diagnosis==
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*'''Peripheral blood smear'''<ref>http://www.cdc.gov/ehrlichiosis/symptoms/index.html#diagnosis</ref>
 
*Obligate intracellular organism
 
*Obligate intracellular organism
**Peripheral blood smear shows intracellular parasites only 20% of time
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**Smear shows intracellular parasites only 20% of time
*PCR
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*'''PCR'''
 
**Most sensitive in first week of illness
 
**Most sensitive in first week of illness
*Indirect Immunoflorescence Assay
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*'''Indirect Immunoflorescence Assay''''
**'''Gold Standard'''
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**''Gold Standard''
 
**Negative 85% of time in first 7 days of illness
 
**Negative 85% of time in first 7 days of illness
 
**Compare 2 samples drawn at different times
 
**Compare 2 samples drawn at different times
***4 fold increase in titers of second draw is positive
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**4 fold increase in titers of second draw is positive
*Enzyme Immunoassay
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*'''Enzyme Immunoassay'''
 
**Qualitative tests, not quantitative
 
**Qualitative tests, not quantitative
 
*Leukopenia, elevated transaminases, thrombocytopenia often present
 
*Leukopenia, elevated transaminases, thrombocytopenia often present
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==Sources==
 
==Sources==
*Wikipedia
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<references/>
*cdc.gov/parastites/ehrlichiosis
 
*uptodate.com
 
  
 
[[Category:ID]]
 
[[Category:ID]]

Revision as of 19:46, 5 December 2014

Background

  • Bacterial infection of the family Anaplasmataceae common in mammals such as cattle, dogs, sheep, goats, and horsesCite error: Closing </ref> missing for <ref> tag
    • More severe disease in immunocompromised patients (HIV, Elderly, Asplenic)

Symptoms

  • Fever, chills, headache, malaise, myalgias, nausea, vomiting, diarrhea, conjunctival injection
    • Up to 60% of children may have a rash (30% of adults)

Diagnosis

  • Peripheral blood smear[1]
  • Obligate intracellular organism
    • Smear shows intracellular parasites only 20% of time
  • PCR
    • Most sensitive in first week of illness
  • Indirect Immunoflorescence Assay'
    • Gold Standard
    • Negative 85% of time in first 7 days of illness
    • Compare 2 samples drawn at different times
    • 4 fold increase in titers of second draw is positive
  • Enzyme Immunoassay
    • Qualitative tests, not quantitative
  • Leukopenia, elevated transaminases, thrombocytopenia often present

Treatment

  • Doxycycline
    • 100mg BID (Adults)
    • 2.2mg/kg BID (children)

See also

Tick Borne Illnesses

Sources