Tick borne typhus (RMSF)

Question 1

RMSF (time)

Answer 1

spring and summer

Question 2

RMSF (place)

Answer 2

US, canada, mexico, S.america

Question 3

RMSF (agent)

Answer 3

Ricketssia Ricketssia

Question 4

RMSF (vector)

Answer 4

dermacenter variabillis (ticks from rodents or dogs)

Question 5

RMSF (pathogeneis)

Answer 5

Inoculated into dermis with secretions from ticks salivary glands, -> lymphohematogenously -> infect like prowakezii
Inflammation and injury to vascular endothelium -> small haemorrages and widespread vasculitis
increase vascular permeability -> edema, hypovolemia and ischemia

Question 6

RMSF (clinical)

Answer 6

1) nonspecific - fever headache, rash on site of bite, myalgia, malaise, nausea, vomiting, conjunctivitis, HSM
2) 3-5 days after -> maculopapular rash (blanching, starts on extremities - WRISTS and ankles and spreads to trunk, spars face, palms and soles -> petetchiae
SEVERE HYPOVOLEMIA AND LOW BP, DIZZINESS AND LOSS OF CONSCIOUSNESS

Question 7

RMSF (complications)

Answer 7

CNS - meningitis or encephalitis, ARDS, vasculitis -> SIRS -> shock/edema/DIC/RF

Question 8

RMSF (diagnosis)

Answer 8

Serology - ELISA or IF for IgG

PCR - skin biopsies

Question 9

RMSF (treatment)

Answer 9

Doxycyline