Laryngopharyngeal Reflux

Laryngopharyngeal Reflux (LPR)

Laryngopharyngeal refulx (LPR), also known as the silent reflux (no belching or vomiting), is the retrograde flow of gastric contents into the larynx and pharynx (nasopharynx, oropharynx and laryngopharynx). The effect of gastric acid on the larynx and pharynx causes and inflammatory response and a litany of symptoms such as dysphonia, cough, wheeze and many more.

• Factors that prevent reflux in healthy individuals
  • Lower esophageal sphincter
  • Upper esophageal sphincter
  • Peristalsis
  • Epithelial resistance factors such as a mucus layer and aqueous layer on the mucosa that protect the esophagus from the effects of gastric acid.
  General anesthesia, sleep and smoking weaken the lower esophageal sphincter predisposing one to reflux. GERD primarily affects the lower esophageal sphincter while LPR affects the upper esophageal sphincter.
• Risk factors for LPR
  • Consuming a diet heavy in acidic or fatty foods
  • Caffeine or alcohol
  • Eating large meals before going to sleep
  • Obesity
  • Smoking
• Pathophysiology
  • The difference between GERD and LPR lies in the anatomical site affected as mentioned above and the symptoms manifested.
  • This difference is thought to occur due to the difference in epithelium lining the oesophagus and larynx.
  • The esophagus is lined by hardy stratified squamous epithelium which can stand the acidic effects of gastric contents 50 times more than the fragile respiratory epithelium of the larynx and nasopharynx. Thus the difference in manifestation.
  • Once exposed to gastric contents the ciliary action of the respiratory epithelium is halted ( impeded at pH 5.0 and stopped at pH 2.0). The mucosa is damaged and this causes:
    • Reduced infection resistance due to defective cilia
    • Chronic coughing due to vagal stimulation
    • Hoarse voice due to involvement of the vocal cords
  N.B: Respiratory epithelium is ciliated pseudostratified columnar epithelium.
• Signs and symptoms
  • Hoarseness
  • Post nasal drip
  • Globus sensation
  • Chronic cough
  • Chronic throat clearing
  • Pain referred to the ear due to shared vagus nerve supply
  • Night time choking spells due to mucus getting stuck in the throat
  • Dysphagia
  • Odynophagia
  • Wheeze
  • Indigestion
  • Regurgitation
  Children and infants also present with recurrent pneumonia, stridor, poor feeding and failure to thrive.
• Physical examination
  • Edema of the false and true vocal cords
  • Diffuse laryngeal and pharyngeal edema
  • Erythema
  • Hyperemia
  • Thickened mucus
  • Mucosal ulcers
  • Subglottic stenosis
  • Thickening and pachydermia of the posterior laryngeal commissure and post-cricoid mucosa
• Differentials
  • Laryngitis
  • Laryngeal stenosis
• Investigations
  • Laryngopharyngoscopy
  • CT scan
  • Barium swallow
  • Ambulatory 24 hour pharyngoesophageal pH monitoring using a nasal catheter
• Treatment – Lifestyle modification
  • Reduce portions of food eaten and avoid lying down soon after meals (give about 2-3 hours before lying down)
  • Avoid alcohol and caffeine
  • Avoid fasting
  • Avoid tight clothing
  • Weight loss
  • Stopping tobacco use
• Medical treatment Proton pump inhibitors 40mg BD for 1-3 months Surgical therapy such as Nissen fundoplication can also be employed to decrease symptoms.