1. Rickettsia typhi
Domina Petric, MD

2. Etiology Rickettsia typhi is obligate intracellular parasite.
Transmission vector is rat flea.
Disease is called murine typhus (endemic typhus).

3. Patology
This bacteria affects endotel cells of small blood vessels: focal lymphohistiocytic vasculitis.

4. Clinical presentation
Incubation period: 7 to 14 days (usually 12 days).
Abrupt onset: high temperature, headache, shivering, nausea, myalgias.
Symptoms can progress to vomit and anorexia.

5. Clinical presentation
Rash can occur immediately or after few days from the first symptoms:
maculopapular rash (78%)
petechiae (10%)
on the trunk mostly

6. Clinical presentation
Disease is usually mild, but in 4% of the patients there can be severe form (treatment in ICU).
Rare clinical presentations: affection of CNS, renal, hepatal and respiratory insufficiency, hematemesis.

7. Best Online MD

8. Laboratory findings
leukopenia and thrombocytopenia during first week of the disease
leukocytosis later on
ALT, AST, LDH, ALP levels are elevated
PV can be low
hypoproteinemia, hyponatremia, hypocalcemia
pleocytosis in CSF

9. Treatment
Doxycycline 100 mg twice a day per os.
Treatment duration: 48 to 72 hours after body temperature drops.

10. Literature www.bestonlinemd.com
Begovac J. Božinović D. Lisić M. Baršić B. Schönwald S. Infectology, Profil.