Makindo Medical Notes

Related Subjects: |Achalasia |American Trypanosomiasis (Chagas Disease) |Oesophageal Carcinoma |Diffuse Oesophageal spasm |Diffuse Oesophageal Perforation - Rupture |Gastro-Oesophageal Reflux

Lost pleasure with nosh
Chest fills, an audible slosh
Foul fermenting food
Swallow study, contrast squeak
Wide tube tapers to bird’s beak
@DrCindyCooper

Achalasia

Achalasia is a rare and chronic disorder characterized by the degeneration of nerves in the oesophagus, specifically impacting the ganglion cells in the myenteric plexus, leading to disrupted motility and swallowing difficulties.

About

• Achalasia is a primary motility disorder of the oesophagus, affecting the ability to pass food and liquids due to muscle dysfunction.
• In older patients, it is crucial to rule out oesophageal cancer first, as symptoms can overlap.
• The term "Achalasia" is derived from Greek, meaning "fails to relax," which refers to the inability of the lower oesophageal sphincter (LES) to relax during swallowing.

Epidemiology

• Primarily affects individuals between 30 and 60 years but can occur at any age.
• Incidence rate: approximately 1 in 100,000 people annually worldwide.

Aetiology and Pathophysiology

• The Lower Oesophageal Sphincter (LES) fails to relax, leading to reduced oesophageal peristalsis.
• This creates a functional obstruction that prevents the smooth passage of food and liquids into the stomach.
• Loss of ganglionic cells in the myenteric plexus and reduced synthesis of nitric oxide and vasoactive intestinal polypeptide disrupt oesophageal function.
• Nerve degeneration from the vagus nerve can be observed in patients, contributing to the reduced motility.
• Achalasia has similar pathophysiological features to Chagas disease, particularly in endemic areas of South America.

Clinical Features

• Dysphagia to both solids and liquids, often described as a sensation of food “getting stuck” after swallowing.
• Inability to belch effectively, leading to discomfort from gas buildup.
• Patients often drink fluids after eating to help food pass through the LES or use Valsalva-like maneuvers to force food down.
• Symptoms are worse when eating quickly or under stress, and regurgitation of undigested food is common.
• Additional symptoms include chest pain, weight loss, hiccups, and reflux-like symptoms.

Investigations

• Blood tests: FBC, U&E, LFTs, and Glucose to assess general health.
• Chest X-Ray (CXR): May reveal a wide, dilated esophagus with a fluid level, absence of a fundal gas shadow, or evidence of aspiration pneumonia.
• Barium swallow: Classic "bird's beak" appearance due to narrowing at the LES with dilation above it.
• Oesophageal Manometry: The gold standard for diagnosis; shows elevated LES pressure (> 45 mmHg), failed relaxation, and lack of distal peristalsis.
• Endoscopy: Helps exclude strictures and tumors and confirms oesophageal dilation.
• Serology for Trypanosoma cruzi if the patient has a history of residing in or visiting areas endemic for Chagas disease.

Differential Diagnosis

• Oesophageal cancer: Cancer-related dysphagia initially affects solids more than liquids, while achalasia affects both equally.
• Oesophageal Stricture: Can be benign (e.g., from GERD) or malignant; endoscopy and biopsy can differentiate these.
• Chagas Disease: Common in South America, with serology testing available for diagnosis.

Management

• Medications: Calcium channel blockers (e.g., Nifedipine) or nitrates (e.g., GTN spray) can reduce LES tone, though they often cause side effects like flushing and headache.
• Botulinum toxin injections: Temporarily effective in about 85% of patients by inhibiting acetylcholine release at motor neuron terminals. However, repeat injections may be needed as the effect diminishes over time.
• Endoscopic pneumatic balloon dilation: Used to widen the LES by tearing muscle fibers; carries a risk of perforation.
• Surgical intervention (Heller's myotomy): A minimally invasive extramucosal cardiomyotomy often combined with fundoplication to prevent reflux, performed via a thoracic or abdominal approach.
• Reflux management: Eating slowly, thorough chewing, drinking water with meals, elevating the head of the bed, and avoiding large meals before bedtime can help alleviate symptoms.
• Cancer surveillance: Long-standing achalasia slightly increases the risk of oesophageal cancer, warranting regular follow-ups.

Complications

• Aspiration pneumonia: A common risk, especially at night, due to regurgitation of food.
• Increased risk of oesophageal squamous carcinoma: Risk is 15 times higher in patients with chronic achalasia.
• Malnutrition and weight loss: Result from prolonged difficulties with food intake.

References

• Guidelines for the Surgical Treatment of Oesophageal Achalasia