245.3 🩺 內科專科考前版

245.3.0.1 1⃣ Disseminated Histoplasmosis Workup

  • HIV + CD4 < 100 + fever + pancytopenia + hepatosplenomegaly + oral / mucosal lesions → urgent workup
  • Urinary antigen + serum antigen
  • Bone marrow biopsy + culture (high yield)
  • Imaging: CT chest + abdomen + brain + adrenal
  • Endocrinology consult if adrenal insufficiency
  • Long maintenance until immune recovery

245.3.0.2 2⃣ Itraconazole vs Posaconazole

  • Itraconazole — classic; variable absorption
  • Posaconazole — alternative; better tolerated; broader spectrum
  • Voriconazole — limited Histoplasma data
  • Isavuconazole — newer alternative
  • AmB for severe / refractory / pregnancy

245.3.0.3 3⃣ Cave Exposure + Histoplasmosis

  • Spelunkers (caves with bat populations)
  • Massive inoculum possible → severe acute disease
  • Outbreaks reported
  • Awareness for exposure + delayed onset

245.3.0.4 4⃣ Demolition + Construction Workers

  • Old building demolition (urban renewal areas)
  • Dust + bird droppings + soil disturbance
  • Outbreaks possible
  • Occupational exposure assessment
  • Pre-exposure prophylaxis sometimes considered

245.3.0.5 5⃣ POHS (Presumed Ocular Histoplasmosis Syndrome)

  • Choroidal lesions on ophthalmoscopy
  • Often without active disease
  • “Histo spots” — pigmented choroidal scars
  • Macular involvement → vision threat
  • Anti-VEGF therapy for choroidal neovascularization
  • Ophthalmology

245.3.0.6 6⃣ Endocrinology — Adrenal Insufficiency

  • Disseminated histoplasmosis common cause
  • CT shows bilateral adrenal masses
  • Confirm with serum cortisol + ACTH
  • Replacement glucocorticoid + sometimes mineralocorticoid
  • May persist after histo Tx; lifelong replacement common

245.3.0.7 7⃣ Pre-Immunosuppression in Endemic

  • Patients from endemic regions starting anti-TNF, transplant, chemo, anti-CD20:
    • Consider Histoplasma serology + antigen
    • Pre-emptive Tx if positive
    • Long-term prophylaxis controversial

245.3.0.8 8⃣ 健保 / Taiwan

  • 眕芋 endemic; imported cases from Americas
  • 通報 mandatory
  • 健保 itraconazole + AmB + voriconazole
  • ID + endocrinology consultation

245.3.0.9 9⃣ Travel + Returning

  • Returning from Ohio / Mississippi valleys / Latin America + acute respiratory illness + flu-like → consider acute histoplasmosis
  • Detailed exposure history (caves, demolition, gardening)
  • Urinary antigen + imaging

245.3.0.10 10. Newer + Future

  • mRNA fungal vaccines researched
  • Improved diagnostics (PCR, multiplex panels)
  • Pan-fungal biomarkers
  • Newer azoles (isavuconazole expanding indications)