156.1 🎓 醫孞生版

156.1.0.1 📌 䞀頁重點

  • 菌: Gram + rod、facultative intracellular、cold-tolerant (4°C grow, 冷藏熟食!) 、tumbling motility
  • 臚床䞉族矀:
    1. å­•å©Š: flu-like, chorioamnionitis, fetal loss, neonatal sepsis (granulomatosis infantiseptica)
    2. 新生兒: early-onset (產道) / late-onset (院內 meningitis)
    3. 老人 / 免疫䜎䞋: meningoencephalitis (brainstem; rhombencephalitis 特有), bacteremia
  • 食源: 冷藏熟食 (deli meat, soft cheese, hot dogs, melon, ice cream, smoked fish, sprouts)
  • 驖遾: Ampicillin (或 PCN G) + Gentamicin (synergy)
  • PCN 過敏: TMP-SMX
  • Cephalosporins 通通沒甚 (intrinsic R)
  • 疫情: 2011 矎 cantaloupe (33 æ­»), 2024 玉米/cookies/deli outbreak

156.1.0.2 1⃣ 现菌孞

  • Gram + rod, short, motile (tumbling at 25°C, 䞍動 at 37°C)
  • Catalase +
  • β-hemolysis on blood agar (weak)
  • Cold tolerant — 4°C 可長 (冷藏熟食危險)
  • Salt tolerant — 高鹜食品
  • Facultative intracellular: actin-based motility, cell-to-cell spread
  • 13 serovars, 1/2a, 1/2b, 4b 占倧宗 human disease
156.1.0.2.1 臎病機蜉
  • Internalin (InlA, InlB): 入䟵 enterocyte (gut), placenta, BBB
  • Listeriolysin O (LLO): 逃 phagosome → cytoplasm
  • ActA: actin tail → cell-to-cell spread (avoid extracellular Ab)
  • 现胞媒介免疫 (T cell, macrophage) > humoral

156.1.0.3 2⃣ 臚床衚珟

156.1.0.3.1 A. 健康成人
  • Febrile gastroenteritis (24-48h, self-limited, watery diarrhea, fever)
  • 䞍需抗生玠 通垞
156.1.0.3.2 B. å­•å©Š (~ 13× general population risk)
  • 第䞉孕期最高
  • Flu-like (fever, headache, myalgia)
  • Chorioamnionitis → preterm labor, fetal loss, stillbirth, neonatal sepsis
  • Granulomatosis infantiseptica: 倚臟噚 microabscess + granuloma
  • Treatment: amp 2 g IV q4-6h × 2 wk (å­•å©Š) → 防 placental seeding
156.1.0.3.3 C. 新生兒
  • Early-onset (< 7d): in utero / 產道, sepsis + pneumonia, 死亡高
  • Late-onset (1-3 wk): meningitis, mortality 范䜎
156.1.0.3.4 D. 老人 / 免疫䜎䞋 / 慢病
  • Meningoencephalitis + Rhombencephalitis (Listeria 特色 — brainstem)
  • Cranial nerve palsies, ataxia, dysarthria
  • CSF: PMN or lymph; gram stain 垞芋 (~ 40%); culture 確認
  • Sepsis / bacteremia 無 source
156.1.0.3.5 E. 局郚感染
  • Endocarditis (rare)
  • Brain abscess
  • Septic arthritis
  • Wound (vet, butcher)

156.1.0.4 3⃣ 蚺斷

  • Blood culture — 重芁; 泚意 lab 可胜誀為 “diphtheroid contaminant”
  • CSF: gram + rod; 培逊
  • PCR (CSF, blood)
  • GI: stool culture not routine (low yield, gastroenteritis self-limit)
  • Public Health notification + outbreak investigation

156.1.0.5 4⃣ 治療

156.1.0.5.1 A. Bacteremia / Meningitis
  • Ampicillin 2 g IV q4h × ≥ 14d (meningitis 21d)
      • Gentamicin × first 7-10d for synergy (controversial 䜆 IDSA 仍建議 IE / severe)
  • PCN G 也可 (高劑量, 倧 dose)
  • PCN 過敏: TMP-SMX 5 mg/kg q6h IV (synergistic activity)
  • Cephalosporins 通通沒甚 (intrinsic R) — 經驗 meningitis 必須加 amp covers Listeria!
156.1.0.5.2 B. å­•å©Š
  • Amp 2 g IV q4h × 14d
  • IV èµ· (䞍口服 — bioavail/placental concentration)
156.1.0.5.3 C. Rhombencephalitis / Severe
  • Amp + gent × ≥ 21d
  • Some advocate 6 wk for brain abscess
156.1.0.5.4 D. 預防
  • 高危人 (å­•å©Š, 免疫䜎䞋): 避 deli meat, soft cheese, raw milk, smoked fish, sprouts, melon precut
  • 熟食冷藏 < 4°C × < 5 days
  • 埮波加熱 75°C+