186.4 📌 章末速蚘

  • Rickettsiae: obligate intracellular gram-, endothelium-tropic
  • 3 groups:
    • SFG: RMSF (Americas), Mediterranean spotted (tâche noire), African tick-bite, rickettsialpox
    • Typhus: epidemic (louse, refugees), endemic/murine (flea, Asia/USA Gulf), Brill-Zinsser
    • Scrub typhus (Asia-Pacific, Taiwan endemic!, eschar pathognomonic)
  • RMSF rash centripetal (wrists/ankles → palms/soles → trunk); 30% no rash first 3d (“spotless”)
  • Treatment: doxycycline 100 bid × 5-7d for all — empirical (kids + pregnancy if life-threatening)
  • Defervescence 48 hr = diagnostic response
  • Search eschar (groin, axilla, scalp, behind ears)
  • 盧醫垫 hint: 鄉村 / 倖島 fever + headache → scrub typhus until R/O