144.1 🎓 醫孞生版

144.1.0.1 📌 䞀頁重點

  • Chronic meningitis: symptoms or CSF abnormalities ≥ 4 weeks
  • 病因:
    • Infectious: TB (Mycobacterium tuberculosis), Cryptococcus (HIV), Coccidioides, Histoplasma, Blastomyces, Treponema (neuro syphilis), Borrelia (Lyme), Brucella, Nocardia
    • Non-infectious: cancer (leptomeningeal carcinomatosis, lymphoma), sarcoidosis, vasculitis, Behçet, autoimmune (anti-NMDA chronic), drug-induced (NSAIDs, IVIG, TMP-SMX)
  • Recurrent meningitis:
    • Anatomic (CSF leak after trauma) → S. pneumoniae repeats
    • Mollaret’s (recurrent aseptic): HSV-2 most
    • Drug-induced: NSAIDs, IVIG, TMP-SMX
  • CSF: lymphocytic predominant + low glucose (TB, fungal) + ↑↑ protein

144.1.0.2 1⃣ TB Meningitis (重芁 — Asian context)

144.1.0.2.1 Clinical
  • Insidious onset (weeks)
  • Fever, headache, vomiting, lethargy → basal meningitis (cranial nerve palsies: VI, VII, III)
  • Stage I: alert, no neuro deficit
  • Stage II: lethargy, cranial nerve palsy
  • Stage III: stupor, coma, seizure
144.1.0.2.2 Diagnosis
  • CSF: lymphocytic pleocytosis (50-500), protein ↑↑ (often > 200), glucose ↓ (< 40)
  • AFB smear (low sensitivity, 10-30%)
  • CSF mycobacterial culture (4-8 weeks)
  • GeneXpert MTB/RIF in CSF (90% sensitivity, RIF resistance detection)
  • MRI: basal enhancement, hydrocephalus, infarcts, tuberculomas
  • IGRA / TST (only support, not definitive)
144.1.0.2.3 Treatment
  • RIPE × 2 mo (RIF + INH + PZA + EMB) + INH/RIF × 7-10 mo = 9-12 month total
  • Dexamethasone (Thwaites trial 2004 NEJM): reduces mortality + improves outcome × 6-8 weeks taper
  • 監枬 hydrocephalus (VP shunt may be needed)

144.1.0.3 2⃣ Cryptococcal Meningitis

144.1.0.3.1 Risk Factors
  • HIV / AIDS (CD4 < 100) #1
  • Solid organ transplant
  • Steroid use, biologics, chemotherapy
  • Sarcoidosis
144.1.0.3.2 Clinical
  • Insidious headache, fever, mental status changes
  • ICP ↑↑ (papilledema, vision changes)
  • Slow onset — weeks
144.1.0.3.3 Diagnosis
  • CSF:
    • Opening pressure ↑↑↑ (often > 25 cm H2O, can be 50+)
    • Lymphocytic pleocytosis (but in AIDS can be minimal)
    • Mild ↑ protein, mild ↓ glucose
  • India ink stain (50-80% sensitivity, especially HIV)
  • CSF Cryptococcal antigen (CrAg) — highly sensitive + specific
  • Serum CrAg — screening (HIV with CD4 < 100)
  • CSF culture — gold standard
144.1.0.3.4 Treatment
Phase Regimen Duration
Induction Liposomal amphotericin B 3-4 mg/kg/d IV + Flucytosine 100 mg/kg/d PO 2 weeks
Consolidation Fluconazole 800 mg/day 8 weeks
Maintenance Fluconazole 200 mg/day ≥ 1 year (HIV: until CD4 > 100 + viral load suppressed 3-6 mo)
144.1.0.3.5 ICP Management
  • Therapeutic LP for opening pressure > 25 cm H2O (drain to halve)
  • Daily LPs as needed
  • Lumbar drain or VP shunt if refractory

144.1.0.4 3⃣ Other Chronic Meningitis

144.1.0.4.1 Syphilis (Tertiary / Neurosyphilis)
  • HIV + 颚險倍增
  • Clinical: meningovascular (stroke), general paresis (dementia), tabes dorsalis (sensory ataxia), gummas
  • CSF: lymphocytic + protein ↑ + VDRL+ (specific but only 50% sens) / FTA-ABS+ (more sens)
  • Tx: IV PCN G 18-24 MU/d × 10-14 d
144.1.0.4.2 Lyme Meningitis
  • B. burgdorferi early disseminated (post-EM)
  • CSF: lymphocytic + mild protein ↑ + serology +
  • Tx: ceftriaxone 2g IV daily × 2-4 weeks (or doxycycline if mild)
144.1.0.4.3 Brucella Meningitis
  • Endemic areas (Mediterranean, ME, Asia, S America)
  • Tx: doxy + RIF + streptomycin × months
144.1.0.4.4 Histoplasma / Coccidioides / Blastomyces
  • Endemic mycoses (Histo: Ohio/Mississippi; Cocci: SW US; Blasto: Great Lakes)
  • CSF antigen + culture
  • Tx: liposomal amphotericin B → itraconazole / fluconazole
144.1.0.4.5 Carcinomatous Meningitis (Leptomeningeal Carcinomatosis)
  • Breast, lung, melanoma, lymphoma
  • Cranial nerve palsies + diffuse neuro deficit
  • CSF cytology (× 3 LP, 50%+ yield) + flow cytometry (hematologic)
  • MRI: leptomeningeal enhancement
  • Tx: intrathecal chemotherapy + radiation (palliative)
144.1.0.4.6 Sarcoidosis (Neurosarcoidosis)
  • Cranial neuropathy (VII most), meningitis, mass lesions
  • ACE in CSF (low specificity), serum ACE
  • MRI: dural, leptomeningeal, cranial nerve enhancement
  • Tx: steroid + methotrexate / infliximab

144.1.0.5 4⃣ Recurrent Meningitis

144.1.0.5.1 Anatomic Defect → Recurrent Bacterial
  • CSF leak (post-trauma, post-surgery, congenital encephalocele, cribriform plate fracture)
  • Repeated S. pneumoniae meningitis
  • Imaging: CT cisternography, MRI, β2-transferrin in nasal secretion
  • Surgical repair
144.1.0.5.2 Mollaret’s Meningitis
  • Recurrent aseptic episodes (3+)
  • HSV-2 (mostly), HSV-1
  • “Mollaret cells” in CSF (large monocytes — non-specific)
  • Tx: acyclovir / valacyclovir suppression long-term
144.1.0.5.3 Drug-Induced Aseptic Meningitis (DIAM)
  • NSAIDs (ibuprofen most), TMP-SMX, IVIG, OKT3 (anti-CD3), lamotrigine, vaccines
  • Lupus pre-disposition for NSAID DIAM
  • Stop drug → resolves in days
144.1.0.5.4 Behçet’s Disease
  • Recurrent oral + genital ulcers + uveitis + meningoencephalitis
  • HLA-B51
  • Tx: steroid + immunosuppressant