Ver el código de «Murine typhus»

''Not to be confused with [[typhoid fever]], a distinct disease caused by a different genera of bacteria''
==Background==
*Also known as "'''endemic''' typhus" and "fleaborne typhus"
*Caused by Rickettsia typhi
**Gram negative, obligate, intracellular bacterium
**Replicates in epithelial cells of flea's midgut

{{Typhus types chart}}

===Vector===
*Infection is transmitted by fleas
**Typically rat fleas
**Also Rickettsia felis (indistinguishable from R. typhi) carried by fleas on opossum and cats
*Feces containing R. typhi are deposited into wound made by flea bites

*Found in areas with large populations of urban rats
**United States
***Southern Texas
***Southern California
**Internationally: Tropical/Subtropical urban seaboard regions

*Seasonal predilection for summer months
**Texas: Spring to summer
**California:  Summer to fall

==Clinical Features==
*Incubation period: 7-14 days
[[File:Murine_Typhus.png|thumb|Rash of Murine Typhus]]
[[File:PMC2729230 wjem-10-207f1.png|thumb|Diffuse rash consisting of multiple, small, erythematous, and confluent macules.]]
===Symptoms===
*Variable and non-specific
*Often presents as acute, self-limited illness, with no complications<ref>Civen R, Ngo V, 2008. Murine typhus: an unrecognized suburban vectorborne disease. Clin Infect Dis 46: 913–918.</ref>

;Most Common Symptoms
*[[Fever]]
**Can last ~1 week
*[[Rash]]
**Macular or maculopapular, blanching, non-pruritic
**Starts centrally and moves to the extremities
**Can involve palms/soles but usually sparing
**Starts 6-7 days after symptom onset (fever onset)
*[[Headache]]
*[[Arthralgia]]s

;Other Symptoms
*[[Hepatomegaly]]
*Splenomegaly
*[[Cough]]
*[[Diarrhea]]
*[[Nausea/Vomiting]]
*[[Abdominal pain]]
*[[Confusion]]

==Differential Diagnosis==
*Non-specific [[viral syndrome|viral illness]]
*Most common admitting diagnosis in one case study was "fever of unknown origin"<ref>Civen R, Ngo V, 2008. Murine typhus: an unrecognized suburban vectorborne disease. Clin Infect Dis 46: 913–918.</ref>
{{Tick borne illnesses DDX}}
{{Template:Fever in Traveler DDX}}

==Evaluation==
*Infectious work up
**Not sensitive or specific
**CBC- can show [[anemia]] and [[thrombocytopenia]]
**[[LFTs]]- often elevated 3-5x normal
**[[Lumbar puncture]]- resembles aseptic meningitis 
===Diagnostic labs===
*Immunofluorescent assay is the gold standard
**Becomes diagnostic with time.  Rarely positive at onset of illness.
*PCR

==Management==
*[[Doxycycline]] 100mg BID continue for 3 days after resolution of symptoms<ref>Civen R, Ngo V, 2008. Murine typhus: an unrecognized suburban vectorborne disease. Clin Infect Dis 46: 913–918.</ref>
**Children - 2.2mg/kg BID
*[[Chloramphenicol]] 50-100mg/kg/day div Q6hr (Max dose = 4g/day)

==See Also==
*[[Typhus]]

==External Links==

==References==
<references/>

[[Category:ID]]