186.2 📚 國考版

186.2.0.1 必背 — 3 Groups

Group	Vector	Geography
Spotted fever (RMSF)	Tick	Americas
Typhus (epidemic)	Louse	Africa, S America, refugee
Typhus (murine)	Flea	USA Gulf, Asia
Scrub typhus	Chigger mite	Asia-Pacific (Taiwan!)

186.2.0.2 必背 — RMSF Rash Pattern

• Centripetal (wrists/ankles → palms/soles → trunk) — opposite epidemic typhus

186.2.0.3 必背 — Eschar Pathognomonic

• Boutonneuse fever (Mediterranean) — tâche noire
• Scrub typhus — eschar (search axilla, groin, scalp)
• African tick-bite — multiple eschars

186.2.0.4 必背 — Treatment

• Doxycycline 100 mg bid × 5-7d for ALL rickettsial empirically
• Children + Pregnancy: doxy if life-threatening (2018 IDSA safe < 21d)
• Scrub typhus alt: azithromycin

186.2.0.5 必背 — Empirical Treatment

• Don’t wait for serology — delays kill
• Fever + headache + outdoor exposure + endemic + clinical suspicion → empirical doxy

186.2.0.6 必背 — “Spotless” RMSF

• 30% lack rash first 3 days
• High suspicion in endemic areas + delayed dx = death

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