Dysphagia is the medical term for the symptom of difficulty in swallowing. Although classified under "symptoms and signs" in ICD-10, the term is sometimes used as a condition in its own right. Sufferers are sometimes unaware of their dysphagia.
It is derived from the Greek dys meaning bad or disordered, and phago meaning "eat". It is a sensation that suggests difficulty in the passage of solids or liquids from the mouth to the stomach. Dysphagia is distinguished from other symptoms including odynophagia, which is defined as painful swallowing, and globus, which is the sensation of a lump in the throat. A psychogenic dysphagia is known as phagophobia.
It is also worthwhile to refer to the physiology of swallowing in understanding dysphagia.
Some patients have limited awareness of their dysphagia, so lack of the symptom does not exclude an underlying disease. When dysphagia goes undiagnosed or untreated, patients are at a high risk of aspiration and subsequent aspiration pneumonia secondary to food or liquids going the wrong way into the lungs. Some people present with "silent aspiration" and do not cough or show outward signs of aspiration. Undiagnosed dysphagia can also result in dehydration, malnutrition, and renal failure.
Some signs and symptoms of oropharyngeal dysphagia include difficulty controlling food in the mouth, inability to control food or saliva in the mouth, difficulty initiating a swallow, coughing, choking, frequent pneumonia, unexplained weight loss, gurgly or wet voice after swallowing, nasal regurgitation, and dysphagia (patient complaint of swallowing difficulty). When asked where the food is getting stuck patients will often point to the cervical (neck) region as the site of the obstruction. The actual site of obstruction is always at or below the level at which the level of obstruction is perceived.
The most common symptom of esophageal dysphagia is the inability to swallow solid food, which the patient will describe as 'becoming stuck' or 'held up' before it either passes into the stomach or is regurgitated.
Pain on swallowing or odynophagia is a distinctive symptom that can be highly indicative of carcinoma, although it also has numerous other causes that are not related to cancer.
Achalasia is a major exception to usual pattern of dysphagia in that swallowing of fluid tends to cause more difficulty than swallowing solids. In achalasia, there is idiopathic destruction of parasympathetic ganglia of the auerbach submucosal plexus of the entire esophagus, which results in functional narrowing of the lower esophagus, and peristaltic failure throughout its length.
Dysphagia is classified into two major types:
- oropharyngeal dysphagia and
- esophageal dysphagia.
- functional dysphagia is defined in some patients as having no organic cause for dysphagia that can be found.
Causes of oropharyngeal dysphagia include:
- Cerebrovascular Stroke
- Multiple Sclerosis
- Myasthenia gravis
- Parkinson's disease & Parkinsonism syndromes
- Amyotrophic Lateral Sclerosis
- Bell's palsy
- Bulbar Palsy & Pseudobulbar palsy
- Neck malignancies
- Neurotoxins (e.g. snake venom)
- Eosinophilic esophagitis
- Pharyngitis, etc.
Esophageal dysphagia is almost always caused by disease in or adjacent to the esophagus but occasionally the lesion is in the pharynx or stomach. In many of the pathological conditions causing dysphagia, the lumen becomes progressively narrowed and indistensible. Initially only fibrous solids cause difficulty but later the problem can extend to all solids and later even to liquids. Patients with difficulty swallowing may benefit from thickened fluids.
The gold-standard for diagnosing oropharyngeal dysphagia in countries of the Commonwealth are via a Modified Barium Swallow Study or Videofluoroscopic Swallow Study (Fluoroscopy). This is a lateral video X-ray that provides objective information on bolus transport, safest consistency of bolus (honey, nectar, thin, pudding, puree, regular), and possible head positioning and/or maneuvers that may facilitate swallow function depending on each individual's anatomy and physiology. This study is performed by a Speech-Language Pathologist and a Radiologist.
Swallowing disorders can occur in all age groups, resulting from congenital abnormalities, structural damage, and/or medical conditions. Swallowing problems are a common complaint among older individuals, and the incidence of dysphagia is higher in the elderly, in patients who have had strokes, and in patients who are admitted to acute care hospitals or chronic care facilities. Dysphagia is a symptom of many different causes, which can usually be elicited by a careful history by the treating physician. A formal oropharyngeal dysphagia evaluation is performed by a speech-language pathologist.