Rocky mountain spotted fever Flashcards
Etiology
Rickettsia rickettsii
Transmission
Bite of infected tick;only60% of patients are aware of prior tick bite.Most common in
springtime
Clinical manifestation
Abrupt onset of symptoms.
Fever,chills,shaking rigor.
Anorexia, nausea, vomiting. Malaise, irritability. Severe headache. Myalgia.
Can mimic acute abdomen, acute cholecystitis, and acute appendicitis.
Tâche noire uncommon in RMSF.
Early exanthem: 2 to 6 mm, pink, blanchable macules In 1 to 3 days, evolves to deep red papules.
Characteristically, rash begins on wrists, forearms, and ankles and somewhat later on the palms and soles. Within 6 to 18 h, the rash spreads centripetally to the arms, thighs, trunk, and face.
Later exanthem: In 2 to 4 days, become hemorrhagic, no longer blanchable. Local edema. Petechiae may occur on the palms and soles. Necrosis occurs in acral extremities following prolonged hypotension. Pedal edema.
Spotless ever:≤10% of cases.Associated with higher mortalityrate because of the delay in diagnosis.
Treatment
Doxycycline is DOC.
Chloramphenicol