Typhus
Two types of Typhus in Sri Lanka
- Scrub typhus ( Orientia tsutsugamashi)
- Endemic typhus ( Rickettsia typhus)
Typhus
Scrub typhus Vector
Trombiculid mite
Typhus
Endemic typhus vector
Rat flea
Typhus
Epidemic typhus MO
Rickettsia prowazeki
Typhus
Epidemic typhus vector
human body louse ( rare)
Typhus
Ix
Clinical. Rx on suspicion. Hard to Dx
Typhus
Pathogenesis
- Enter into body by tick bite or scratch ( innoculation of tick feces through skin)
- Local lesions - Inflammatory response ( eschar at the bite site, regional lymphadenopathy)
- Becomes generalized ( vasculitis, endovasculitis)
Typhus
Eschar
brown crusted necrotic painless papule - like a cigarette burn mark
Typhus
Endovasculitis causes
rash and bleeding diasthesis
Typhus
Incubation period
2 weeks
Typhus
Sx during acute phase
- swinging fever
- frontal headache
- myalgia
- conjunctival infection
Typhus
Sx progression
- Acute phase - abrupt onset fever, myalgia, frontal headache, conjunctival infection
- Towards the end of the first week- generalized lymphadenopathy, meningism, hepatosplenomegaly, rash
- ESCHAR!!!!!!
Typhus
Fever +Rash»_space;»
Consider typhus and look for an eschar!!!
Typhus
Fever + Rash + deafness/ tinnitus»>
Typhus?
Typhus
Complications
- Pulmonary involvement - pneumonia, pleural effusion
- Neuro - various degrees of meningitis, encephalopathy, deafness, tinnitus
Typhus
Similiarities/ differences to lepto
- liver involvement is rare
- No renal failure in typhus!
Typhus
Rash
Begins as macules on hands and feet and then spreads over the body as petechial hemorrhage
Typhus
Lab Ix
- Weil Felix reaction
- Anti rickettsial Ab test
- FBC
Typhus
Weil Felix reaction test
Not done now. Lack specificity and sensitivity
Typhus
Main confirmatory test
Indirect immune peroxidase test and immune fluorescent test
Typhus
Indirect immune peroxidase test and immune fluorescent test
Anti rickettsial Ab in patient serums, cross reacts and agglutinates with certain somatic Ag of proteus species. DONE NOW
Typhus
FBC
- Leukopenia ( can be normal too)
- Slight neutrophilia
- Thrombocytopenia
Typhus
FBC smiliarity in lepto
Thrombocytopenia
Typhus
Rx
- Dramatic response to tetracyclines
- Also respond to chloramphenicol, fluoroquinolones
