Dysphagia is defined as difficulty in swallowing. It is a common and important symptom. Two types are recognised:
- Oropharyngeal: involving the transfer of food from the mouth into the upper oesophagus.
- Oesophageal: involving the transport of food down the oesophagus and into the stomach.
The significance of this condition relates to its multitude of causes. Dysphagia may be caused by mild muscular spasm or incoordination due to psychological causes or, at the other end of the spectrum, may be progressive, associated with loss of weight and due to a malignant obstruction of the oesophagus. Consequently any patient complaining of the symptom of dysphagia requires full investigation to exclude malignancy, and to effectively treat the condition.
Dysphagia is a common symptom affecting most individuals transiently at some time in life. One of the important causes of dysphagia is adenocarcinoma of the lower oesophagus. This is a tumour that is increasing in incidence throughout the Western World and often occurs in middle-aged males. It is associated with long-standing gastro-oesophageal reflux and the development of Barrett's mucosa in the oesophagus (see Gastro-oesophageal reflux).
There are a variety of other symptoms that may accompany the presence of dysphagia (Symptoms associated with dysphagia). The presence of these symptoms helps in making a clinical diagnosis.
Causes of dysphagia
Problems within the mouth may cause difficulties in swallowing food. Simple examples include painful ulceration or abscesses, severe tonsillitis, lack of teeth, or deformity after head and neck surgery. Many of these problems can easily be excluded, and the causes of dysphagia that raise concern relate to the pharyngo-oesophageal area and the oesophagus itself (Causes of dysphagia).
Diagnosis of the causes of dysphagia
The clinical history can give a major lead to the diagnosis of the cause of dysphagia. For example, difficulty in swallowing fluids rather than solids suggests a muscular incoordination problem. Progressive dysphagia for solids suggests a malignant cause. Dysphagia in the presence of retrosternal pain, associated with regurgitation of fluids may indicate the stricture or carcinoma associated with reflux. Coughing or the aspiration of fluid into the larynx will give a guide to lesions such as cranial nerve palsies. Loss of weight is one of the most important accompanying symptoms of dysphagia, and indicates malignancy. Lymph node and other masses may be palpable in the neck. However, physical signs are usually absent.
Not all investigations need to be carried out in all cases of dysphagia, but in those cases where the diagnosis is difficult or obscure, the whole gamut of investigations may be needed (Management of dysphagia.).
The barium swallow examination provides good views of the upper oesophagus and helps makes the diagnosis of pharyngeal pouch, webs and strictures. However, a negative barium swallow examination in the presence of persistent dysphagia demands further investigation by endoscopy.
Oesophagoscopy and gastroscopy
This is usually the first investigation for dysphagia and is done using flexible endoscopes under intravenous sedation. Care has to be taken to avoid perforation, particularly if there is suspicion of a pharyngeal pouch or if a stricture is present. The oesophagus is carefully examined for abnormalities such as inflammation and stricture. A stricture can usually be easily determined as being benign or malignant. In the absence of stricture, features such as oesophageal dilatation with food residue may suggest achalasia. Rarely, rigid oesophagoscopy is necessary if flexible endoscopy is unsuccessful.
Radiological staging includes computed tomography (CT) examination and, less commonly, magnetic resonance imaging. This can help make the diagnosis in obscure cases, but its major role is helping to stage the extent of malignant disease.
Endoscopic ultrasound is a very effective way of diagnosing abnormalities within the oesophageal wall. It is not useful if there is a tight narrowing in the proximal oesophagus preventing the passage of the instrument. It is the most precise method for detecting the depth of penetration of a cancer into or through the wall of the oesophagus.
Oesophageal motility studies
These are done via a multilumen catheter inserted into the oesophagus via the nose. Propulsive waves in the oesophagus can easily be measured and the response to a swallowing effort detected. Abnormalities can be identified in achalasia, scleroderma and oesophageal spasm.
Twenty-four-hour pH monitoring will help document the degree of oesophageal reflux. Gastro-oesophageal reflux studies using nuclear scan techniques can be helpful in difficult cases. Reflux may be associated with fibrous stricture or oesophageal spasm, thereby causing dysphagia.
Specific causes of dysphagia
Transfer or pharyngo-oesophageal dysphagia
More correctly this is an inability to swallow and is associated with aspiration, coughing and nasal regurgitation. The common cause of this type of problem is a cerebrovascular accident. It produces major problems in attempting to rehabilitate a stroke patient with a bulbar palsy. Feeding via nasogastric tubes or gastrotomy tubes (percutaneous endoscopic gastrostomy [PEG]) may be necessary to provide nourishment.
Motility disorders of the oesophagus
Achalasia of the oesophagus is also known as cardiospasm and is often associated with the presence of a so-called mega-oesophagus. It occurs most commonly in the young to middle-aged (30–60 years). The incidence is 1 in 100 000 people. There are associated neural abnormalities in the ganglia but the exact cause is not known. The dysphagia is intermittent, but progressive in the longer term. It is detected by the patient as being suprasternal in position and occurs for both liquids and solids. Regurgitation is postural and aspiration pneumonitis may occur. Usually only weak oesophageal contractions occur and the condition is painless. In 10% of cases a condition known as ‘vigorous achalasia’ exists. This is regarded as an early stage of the disease and is associated with pain. Oesophageal manometry reveals markedly elevated lower oesophageal sphincter pressures and diminished oesophageal contractions.
In the chronic long-standing case, weight loss and chest pain occur. Pulmonary disease from aspiration of oesophageal content and the development of carcinoma within the dilated oesophagus are significant complications.
diagnosis and treatment
Chest X-ray, barium meal and manometry examinations help to confirm the diagnosis, which may be difficult to determine. Treatment is by surgical division (myotomy) of the hyperactive lower oesophageal sphincter, usually approached laparoscopically. A thoracoscopic approach can also be used. Reflux is a complication after myotomy and an anti-reflux procedure at the time of surgery is commonly performed. An alternative treatment is by manometric dilatation using a balloon placed across the hypertensive lower oesophageal sphincter, which is then expanded causing disruption of the sphincter. The results of both methods of treatment are good in about 90% of cases.
Diffuse oesophageal spasm
This is usually a primary disorder but may be secondary and associated with:
- peptic oesophageal reflux
- ingestion of irritants
- emotion and tension
- possibly an underlying carcinoma.
The patient complains of dysphagia that is often worse for liquids, is intermittent and is noted in the midsternal region. Pain, which is retrosternal and severe, is also common, is sometimes misdiagnosed as being cardiac in origin, and is worse under emotional stress. There is rarely any weight loss. There is marked belching and other indigestion-type symptoms.
The diagnosis is made on X-ray, which shows tertiary contractions in the oesophagus, and motility studies, which show simultaneous, vigorous, repetitive waves in the oesophageal body when the lower oesophageal sphincter relaxes.
Therapy is generally simple, using simple bougienage without rupturing oesophageal muscle, and medication.
This systemic connective tissue disorder is characterised by muscle atrophy, dilatation of the oesophagus and smooth muscle fibrosis. It is diagnosed by motility studies that show a non-contractile oesophagus. Oesophageal reflux is often a contributing and secondary factor causing strictures. No satisfactory therapy exists.
This is a parasitic infection, common in South America. It produces destruction of the ganglia of the oesophagus and an achalasia-type stricture.