Achalasia

Question 1

Aetiology

Answer 1

• aperistalsis of oesophagus
• lower oesophageal sphincter fails to relax
• progressive degeneration of Auerbach’s myenteric plexus
• loss of inhibitory VIP and nitric oxide releasing inhibitory neurons in lower oesophagus–> leave unopposed excitatory cholinergic neurones
• Chaga’s disease (Trypanosoma cruzi)

Question 2

Clinical feature

Answer 2

• progressive dysphagia (particularly to fluid) over months to years
• spasm-like chest pain
• aspiration pneumonia: regurgitation of fluid from dilated oesophageal sac

Question 3

Investigation

Answer 3

• CXR: dilated oesophagus as a mediastinal mass with air/ fluid level, pneumonitis from aspiration of oesophageal contents
• OGD: demonstrate tight cardia/ food residue, exclude pseudoachalasia secondary to benign stricture or neoplasm
• Barium swallow: dilated tortuous oesophagus above smooth tapering stricture (bird beak appearance)
• oesophageal manometry: demonstrate hypertensive lower oesophageal sphincter with aperistaltic oesophagus

Question 4

Complication

Answer 4

• aspiration pneumonitis
• recurrent chest infection
• oesophageal erosions
• oesophageal carcinoma SCC (rare)

Question 5

Treatment

Answer 5

• endoscopic injection of botulinum toxin: paralyse the lower oesophageal sphicnter
• oesophageal pneumatic dilatation under fluoroscopic guidance using plastic balloon: forcible dilatation of gastro-oesophageal junction
• Heller’s Operation (cardiomyotomy) with fundoplication: laparoscopically cutting the muscle layer of lower oesophageal longitudinally (>5cm) down to mucosa and extending at least 2cm on to stomach