Epistaxis

Anterior epistaxis (>90% of cases)

• Source: Kiesselbach plexus (Little’s area) on the anterior nasal septum.
• Anastomosis of 4 arteries:
  1. Sphenopalatine a. (terminal branch of maxillary a.)
  2. Anterior ethmoidal a. (branch of ophthalmic a.)
  3. Greater palatine a. (branch of maxillary a.)
  4. Superior labial a. (branch of facial a.)

Posterior epistaxis

• Source: Sphenopalatine artery (posterolateral wall) or Woodruff’s plexus.
• More common in elderly, hypertensive, or coagulopathic pts.
• Bleeding drains into nasopharynx/oropharynx (risk of aspiration).

Hereditary hemorrhagic telangiectasia (Osler-Weber-Rendu syndrome)

• Etiology & Genetics: Autosomal dominant (AD) vascular dysplasia leading to localized loss of capillary beds and widespread direct arteriovenous malformations (AVMs).
• Key Clinical Features (Curaçao Criteria):
  • Recurrent spontaneous epistaxis: Most common initial presentation. c
  • Mucocutaneous telangiectasias: Small, blanching red macules on lips, tongue, oral mucosa, and fingertips.
  • Visceral AVMs:
    • Pulmonary AVMs: R-to-L shunt $\to$ cyanosis, digital clubbing, reactive polycythemia, and hemoptysis. c
    • GI AVMs: Occult bleeding $\to$ severe iron deficiency anemia (IDA).
    • Hepatic AVMs: Can cause high-output heart failure (HF).
    • Cerebral AVMs: Seizures, headache, intracranial hemorrhage (ICH).
  • Family history: Affected 1st-degree relative.
• Classic Board Exam Complications:
  • Brain abscess: Caused by bacteremia bypassing lung capillary filtration via pulmonary AVMs.
  • Paradoxical embolic stroke: DVT traversing pulmonary AVM to cerebral circulation.
• Diagnostic Workup:
  • Pulmonary AVM screening (Initial): Contrast echocardiography (“bubble study”) showing delayed appearance of bubbles in the left atrium (>3–8 cardiac cycles).
  • Pulmonary AVM confirmation: Chest HRCT.
  • Cerebral AVM screening: Brain MRI with contrast.
  • Labs: Microcytic anemia (bleeding) OR polycythemia (hypoxemia from R-to-L shunt).
• High-Yield Management:
  • Pulmonary AVMs: Transcatheter embolization (coiling) to prevent stroke and brain abscess.
  • Infection prevention: Antibiotic prophylaxis prior to dental/surgical procedures.
  • Symptom & Bleeding control: Nasal humidification/cautery, iron repletion, and Bevacizumab (anti-VEGF) for refractory bleeding.