151.1 🎓 醫孞生版

151.1.0.1 📌 䞀頁重點

  • 菌皮: Gram + diplococcus、有 capsule、α-hemolytic、optochin sensitive、bile soluble
  • 臎病因子: polysaccharide capsule (95+ serotypes)、pneumolysin、IgA protease
  • 臚床四倧: CAP (䞻芁)、急性䞭耳炎、急性錻竇炎、meningitis (成人 #1 cause)
  • 高危: < 2 歲、≥ 65 歲、無脟、HIV、CKD、DM、酒癮、Sickle Cell、cochlear implant
  • 疫苗 (2024 ACIP 曎新):
    • PCV20 單劑 (≥ 65 æ­² 或 19-64 有高危)
    • PCV21 (V116) 2024 FDA 通過 — 涵蓋曎倚老幎垞芋 serotype
    • PPSV23 挞退堎 (PCV20 已涵蓋倧郚分)
  • 抗藥: PRSP (Pen-R S. pneumoniae) ↑ — 改 ceftriaxone ± vancomycin (meningitis)

151.1.0.2 1⃣ 现菌孞

  • Gram + lancet-shaped diplococci (鏡䞋成對, 像子圈)
  • Capsule (polysaccharide): virulence #1; Quellung reaction 可分 serotype
  • Optochin sensitive (vs viridans group resistant)
  • Bile soluble (vs S. mitis 䞍溶)
  • α-hemolysis on blood agar (vs Group A 是 β)
151.1.0.2.1 臎病機蜉
  1. Capsule: 抗 phagocytosis (anti-capsule Ab → opsonization)
  2. Pneumolysin: pore-forming toxin → tissue injury, immune evasion
  3. IgA protease: 黏膜定殖
  4. Phosphorylcholine: 結合 PAFR → invasion
  5. Pili / CbpA: adhesion
151.1.0.2.2 Carriage
  • 錻咜郚正垞菌叢 (5-10% 成人, 20-40% 小孩)
  • Daycare、家庭聚集

151.1.0.3 2⃣ 臚床衚珟

151.1.0.3.1 A. 肺炎 (CAP)
  • å…žåž‹ lobar pneumonia: 急性 onset, rigor, 高燒, 鐵鏜色痰 (rust-colored sputum), pleuritic chest pain
  • Lobar 或 bronchopneumonia X-ray
  • 菌血症 25-30% (越老越高)
  • 䜵癌症: empyema, lung abscess (rare), ARDS
151.1.0.3.2 B. Meningitis
  • 成人 community-acquired meningitis #1 cause
  • 䞉聯埵 (頭痛/癌燒/頞僵硬) 党到 < 50%
  • LP: PMN 升, 葡萄糖 ↓, 蛋癜 ↑, gram + diplococci
  • 死亡率 16-37% (高斌 N. meningitidis)
  • Sequelae: 聜損 (尀其小孩)、focal neuro deficit
151.1.0.3.3 C. 䞭耳炎 / Sinusitis
  • 小孩 #1 cause (急性䞭耳炎)
  • Empiric: amoxicillin (high-dose) ± clavulanate
  • 倚敞小孩會反芆 — PCV 倧幅枛少
151.1.0.3.4 D. 其他
  • Endocarditis: rare, Austrian’s syndrome (pneumonia + meningitis + endocarditis)
  • Septic arthritis (尀其 prosthetic joint)
  • Peritonitis (cirrhosis、nephrotic)
  • Cellulitis (rare, 通垞 immunocompromise)

151.1.0.4 3⃣ 蚺斷

  • Sputum gram stain + culture (lobar pneumonia 高 yield)
  • Blood culture × 2 sets — pneumonia 25-30% +
  • CSF: meningitis å…žåž‹
  • Urinary antigen (BinaxNOW Strep pneumo): 鎖死菌 + 䜆䞍分 serotype, < 50% sensitivity for non-bacteremic CAP
  • PCR (BioFire FilmArray Pneumonia panel): rapid + serotype possible
  • CXR: lobar consolidation
  • Procalcitonin: 升 → bacterial

151.1.0.5 4⃣ 治療

151.1.0.5.1 Pneumonia (Outpatient)
  • No comorbidity: amoxicillin high-dose (1 g q8h) ± macrolide
  • Comorbid / 重症: respiratory FQ (levofloxacin, moxifloxacin) 或 β-lactam + macrolide
  • PRSP: ceftriaxone (普篩 sensitive); high-dose amox often still works (PRSP 圚肺、CSF 䞍同 breakpoint)
151.1.0.5.2 Pneumonia (Inpatient, severe)
  • Ceftriaxone + azithromycin 或 respiratory FQ
  • ICU: ceftriaxone + macrolide (azithro 降 mortality in severe CAP - Restrepo)
151.1.0.5.3 Meningitis
  • Vancomycin + Ceftriaxone (2 g q12h) empirically
  • + Dexamethasone (10 mg q6h × 4d): de Gans 2002 — 降 mortality + hearing loss (S. pneumoniae); 先絊 / 同時抗生玠
  • Pen-S strain: PCN G 4M U q4h 或 ampicillin
  • Course: 10-14 d
151.1.0.5.4 Endocarditis / Joint
  • PCN G 或 ceftriaxone × 4-6 wk

151.1.0.6 5⃣ 預防 — 疫苗 (2024 ACIP)

151.1.0.6.1 PCV13 → PCV15 → PCV20 → PCV21
  • PCV20 (Prevnar 20, 2021): 13 serotypes + 8, 10A, 11A, 12F, 15B, 22F, 33F
  • PCV21 (V116, Capvaxive): 2024 FDA — 老幎人專甚; covers 8 unique serotypes
  • PPSV23 (Pneumovax): 23-valent polysaccharide — 挞退堎 because PCV20 涵蓋足
151.1.0.6.2 掚薊 (CDC ACIP 2024)
對象 方案
< 2 æ­² PCV15 or PCV20 series (2, 4, 6, 12-15 mo)
2-18 高危 PCV15 → PPSV23 ≥ 8 wk later
19-64 高危 PCV20 alone (preferred); 或 PCV15 → PPSV23
≥ 65 歲 PCV20 alone 或 PCV21 (新 option)
無脟、HIV、CKD、cochlear implant PCV20/21 + 確保 PPSV23 cover
151.1.0.6.3 高危人口
  • 解剖/功胜無脟 (sickle cell, splenectomy, 自體免疫)
  • HIV、CKD/ESRD、cirrhosis
  • DM、心肺慢病、酒癮
  • Cochlear implant、CSF leak
  • Immunosuppression (steroid, chemo, transplant)