Ehrlichiosis: Difference between revisions
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==Background== | ==Background== | ||
*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.</ref> | *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.</ref> | ||
*Spread by the Lonestar tick (Amblyomma americanum) | *Spread by the Lonestar tick (Amblyomma americanum) | ||
**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 with case fatality rate of approximately 1.8%<ref>CDC http://www.cdc.gov/ehrlichiosis/stats/</ref> | **People often unaware they are bitten with case fatality rate of approximately 1.8%<ref>CDC http://www.cdc.gov/ehrlichiosis/stats/</ref> | ||
**More severe disease in immunocompromised patients ([[HIV]], Elderly, '''Asplenic''') | **More severe disease in immunocompromised patients ([[HIV]], Elderly, '''Asplenic''') | ||
== | [[File:Lone Star Tick.jpg|thumb|Lone Star Tick (preserved]] | ||
==Clinical Features== | |||
*Fever, chills, headache, malaise, myalgias, nausea, vomiting, diarrhea, conjunctival injection | *Fever, chills, headache, malaise, myalgias, nausea, vomiting, diarrhea, conjunctival injection | ||
**Up to 60% of children may have a rash (30% of adults) | **Up to 60% of children may have a rash (30% of adults) | ||
==Differential Diagnosis== | |||
{{Tick borne illnesses DDX}} | |||
==Diagnosis== | ==Diagnosis== | ||
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*Leukopenia, elevated transaminases, thrombocytopenia often present | *Leukopenia, elevated transaminases, thrombocytopenia often present | ||
== | ==Management== | ||
*Doxycycline | *Doxycycline | ||
**100mg BID (Adults) | **100mg BID (Adults) | ||
**2.2mg/kg BID (children) | **2.2mg/kg BID (children) | ||
==Disposition== | |||
* | |||
==See also== | ==See also== | ||
[[Tick Borne Illnesses]] | *[[Tick Borne Illnesses]] | ||
== | ==References== | ||
<references/> | <references/> | ||
[[Category:ID]] | [[Category:ID]] | ||
[[Category:TropMed]] | |||
Revision as of 11:25, 18 August 2015
Background
- Bacterial infection of the family Anaplasmataceae common in mammals such as cattle, dogs, sheep, goats, and horses[1]
- Spread by the Lonestar tick (Amblyomma americanum)
Clinical Features
- Fever, chills, headache, malaise, myalgias, nausea, vomiting, diarrhea, conjunctival injection
- Up to 60% of children may have a rash (30% of adults)
Differential Diagnosis
Tick Borne Illnesses
- Babesiosis
- Colorado tick fever
- Ehrlichiosis
- Heartland virus
- Lyme
- Murine typhus
- Rocky mountain spotted fever
- Southern tick-associated rash illness (STARI)
- Tick paralysis
- Tularemia
Diagnosis
- Peripheral blood smear[3]
- 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
Management
- Doxycycline
- 100mg BID (Adults)
- 2.2mg/kg BID (children)