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3. Diseases of the oesophagus

Revision as of 12:40, 4 May 2022 by Nikolas (talk | contribs)

Written by ms. Worldwide, edited by Nikolas

This topic covers these pathologies that can occur with the esophagus:

  • Congenital malformations
  • Functional disorders
  • Vascular diseases
  • Inflammations
  • Neoplasms

Focus on the neoplasms. Now let’s get started!

Congenital malformations

Atresia and fistulas

This happens when the congenital segmental closure of oesophagus fails for some reason. This often ends up with fistulas which connect the upper or lower pouches of oesophagus to the trachea or even to the bronchus.

These types of malformations are usually discovered when the baby gets repeated aspiration pneumonia from breast feeding. Surgery is needed to fix this problem.

Functional disorders

Achalasia

Achalasia is a rare disorder of oesophageal motility. It's characterised by inadequate relaxation of the lower oesophageal sphincter (LES) tone due to the degeneration of inhibitory neurons. Food can’t pass through to the stomach normally which results in dilation of the oesophagus, which may lead to more severe complications like perforation.

We have two types, primary and secondary. Primary achalasia is idiopathic and most common, and is caused by idiopathic degeneration of distal inhibitory neurons, so the muscles of the LES sphincter cannot relax.

Secondary achalasia (actually pseudoachalasia) is caused a mechanical cause of obstruction, like a tumour, amyloidosis, or Chagas disease.

Gastroesophageal reflux disease

Gastroesophageal reflux disease (GERD) is a common disease where gastric contents reflux into the oesophagus, causing symptoms like heartburn, regurgitation, and possible severe complications. It's caused by excessive relaxation of the lower oesophageal sphincter, and is therefore sort of the opposite disorder of achalasia.

Risk factors include those which decrease the tone of the LES and/or increase the pressure inside the stomach:

  • Smoking
  • Coffee consumption
  • Alcohol consumption
  • Obesity
  • Pregnancy
  • Scleroderma
  • Sliding hiatal hernia

Most people with GERD only have symptoms but no severe complications. However, chronic GERD may cause Barrett metaplasia and reflux oesophagitis.

We distinguish GERD into one of three types:

  • Non-erosive reflux disease (NERD)
  • Erosive reflux disease (ERD), also called erosive oesophagitis
  • Complicated erosive reflux disease

In NERD, which accounts for 60% of cases, the gastroesophageal mucosa is visibly normal. In ERD, erosions are present on the mucosa. Complicated ERD is characterised by the presence of complications like ulcers, stenosis, or Barrett oesophagus.

Hiatal hernia

In hiatal hernia a portion of the stomach will herniate through the hiatus in the diaphragm that the oesophagus goes through, the oesophageal hiatus. This is a result of increased abdominal pressure and a lax oesophageal hiatus.

We distinguish between two types: Rolling (paraesophageal) and sliding (axial). Sliding hiatal hernia accounts for 95% of cases of hiatal hernia, and is characterised by the gastroesophageal junction and gastric cardia sliding up into the posterior mediastinum.

The rolling type is more severe and is characterised by a portion of the gastric fundus herniating through the oesophageal hiatus, while the gastroesophageal junction and cardia remain in place.

Sliding hiatal hernia is often treated conservatively, while paraoesophageal hiatal hernia is often treated surgically.

Diverticular diseases

A diverticulum is a circumscribed outpouching of the wall of a hollow organ. Oesophageal diverticula may be true diverticula, where all layers of the wall are pouched out, or pseudodiverticula, where the mucosa and submucosa herniate through a weakness in the muscularis propria.

Living with a diverticulum can be hard for a patient as food can get stuck inside and can rot. This may lead to very uncomfortable situations, like dysphagia, aspiration, vomiting and bad breath (halitosis). It can also lead to inflammation of the diverticulum, called diverticulitis. The presence of diverticula is called diverticulosis.

Let’s look at the different types:

Zenker’s diverticulum is a pseudodiverticulum and is found above the upper oesophageal sphincter. It’s the most common type. The outpouching always protrudes posteriorly and can lead to mediastinitis if the diverticulum gets inflamed (diverticulitis).

It’s also a pulsion diverticulum, meaning that it can be caused by increased intraluminal pressure due to inadequate relaxation of the oesophageal sphincter (e.g. caused by achalasia or spastic motility).

Traction diverticulum

This type is formed by the pulling force of the contracting adhesion bands. It’s a true diverticulum which is associated with tuberculosis or mediastinal lymphadenitis, where scarring happens.

Epiphrenic diverticulum

This is also a pulsion diverticulum, meaning it’s a pseudodiverticulum. It is located in the distal most part of oesophagus and is a result of dysfunctions of the lower oesophageal sphincter, like in achalasia.

Vascular diseases

Oesophageal bleedings can actually be a medical emergency. Let’s look at the different types and find out why.

Oesophageal varices

Varices are big vessels formed due to portocaval shunts in patients with portal hypertension. They are usually found in the lower third of the oesophagus and can rupture and cause massive bleedings. This typically occurs in alcoholics, due to alcoholic liver cirrhosis.

Mallory-Weiss syndrome

Mallory-Weiss syndrome refers to severe upper gastrointestinal bleeding caused by longitudinal tears of the oesophageal mucous membrane. This occurs due to high intraluminal pressure, usually due to severe vomiting.

Boerhaave syndrome

Boerhaave syndrome refers to oesophageal rupture due to severe vomiting. This causes severe pain and mediastinal emphysema. It’s an emergency condition and is deadly without surgical intervention.

Inflammations

Reflux oesophagitis

This is the most frequent cause of esophagitis and is caused by chronic gastroesophageal reflux disease. Reflux of acidic gastric contents into the lower oesophagus, like gastric acid and food, causes chemical irritation. The oesophageal mucosa is vulnerable to acid as it was never intended to be exposed to it.

Risk factors for reflux oesophagitis are the same as for GERD, as well as those risk factors which increase stomach acidity:

Infectious oesophagitis

Infectious oesophagitis is rare but is most frequent in immunosuppressed patients.

We can have:

  • Soor oesophagitis (oesophageal candidiasis) – Caused mostly by the Candida fungus but can also be caused by Aspergillus.
  • Herpes oesophagitis – Causes pouched-out ulcers.
  • Cytomegalovirus oesophagitis – Shallow ulcers and the characteristic Owl-eye appearance can be seen in histology.

Eosinophilic oesophagitis

This is actually a pretty recent disease, and is recognized in more and more people. It involves a pronounced eosinophilic infiltration in the oesophagus. Food or other allergens, like pollen, sensitize the patient and leads to Th2-activation. A genetic predisposition is a cause for this as well.

Preneoplastic lesions – Barrett oesophagus

Barrett oesophagus is a consequence of chronic GERD where the chronic acid exposure of the oesophageal mucosa causes intestinal metaplasia (Barrett metaplasia). On histology goblet cells can be seen in the mucosa. It occurs in up to 15% of patients with GERD.

Barrett oesophagus is a precancerous lesion which must be treated or at the very least frequently monitored. It may progress into adenocarcinoma.

Oesophageal cancer

Introduction and epidemiology

There are two major types of oesophageal cancer, adenocarcinoma and squamous cell carcinoma. Both type typically affect elderly men. Oesophageal adenocarcinoma evolves from the Barrett-mucosa and is the most common type of oesophageal cancer in the Western world. Its incidence is rising. It’s usually found in the lower part of the oesophagus.

Oesophageal SCC is more common in developing countries, and the most common type overall. It’s usually found in the middle and upper parts of the oesophagus. Its prognosis is worse than adenocarcinoma.

It’s usually asymptomatic in the early stages, and therefore is rarely discovered until the late stages. In the late stages it may present with non-specific symptoms like weight loss, dysphagia, and dyspepsia. At the time of presentation, most patients already have advanced cancer.

Etiology

Because adenocarcinoma evolves from GERD and Barrett oesophagus, the risk factors are the same as for GERD, especially smoking.

The risk factors for SCC are:

  • Alcohol consumption
  • Smoking
  • Diet low in fruits and vegetables
  • Exposure to nitrosamines in diet
  • Frequent consumption of very hot beverages, like the coffee at McDonalds.