Dysphagia: A Symptom Not a Disease

Copyright: © 2016 Lohe VK, et al. This is an open-access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited. Dysphagia: A Symptom Not a Disease Vidya K Lohe1* and Ravindra P Kadu2 1Sharad Pawar Dental College and Hospital, DMIMS (DU), Maharashtra, India 2Jawaharlal Nehru Medical College and Hospital DMIMS (DU), Maharashtra, India


Introduction
Phagia meaning swallowing and dysphagia means difficulty in swallowing. It is the most likely complaint to be encountered by the dentist. Dysphgia is nearly always a symptom of organic disease rather than a functional complaint.
Dysphagia is defined as a sensation of "sticking" or obstruction of the passage of food through the mouth, pharynx or oesophagus. It should be distinguished from other symptoms related to swallowing. Aphagia (Aphagia is the inability or refusal to swallow. The word is derived from the Ancient Greek prefix α, meaning "not" or "without," and the suffix φαγία, derived from the verb φαγεῖν, meaning "to eat.") Signifies complete esophageal obstruction, which is usually due to bolus impaction and represents a medical emergency.
Difficulty in initiating a swallow occurs in disorders of the voluntary phase of swallowing. However, once initiated, swallowing is completed normally.
Odynophagia means painful swallowing. Frequently, odynophagia, and dysphagia occurs together. Globus pharyngeous is the sensation of a lump in throat. However, no difficulty is encountered when swallowing is performed. Misdirection of food, resulting in nasal regurgitation (During swallowing, the soft palate and the uvula move superiorly to close off the nasopharynx, preventing food from entering the nasal cavity) and laryngeal and pulmonary aspiration of food during swallowing is characteristic of oropharyngeal dysphagia.
Phagophagia meaning fear of swallowing, and refusal to swallow may occur in hysteria, rabies, tetanus, and pharyngeal paralysis due to fear of aspiration [1].

Pathophysiology of Dysphagia
The normal transport of an ingested bolus through the swallowing passage depends on the size of the ingested bolus; the luminal diameter of the swallowing passage; the force of peristaltic contraction; and deglutitive inhibition including normal relaxation of upper and lower esophageal sphincters during swallowing. Dysphagia caused by a large bolus or luminal narrowing is called mechanical dysphagia, whereas dysphagia due to weakness of peristaltic contractions or to impaired deglutitive inhibition causing nonperistaltic contractions and impaired sphincter relaxation is called motor dysphagia [1].

Classification of Dysphagia
• Oropharyngeal dysphagia is usually described as the inability to initiate the act of swallowing. It is a "transfer" problem of impaired ability to move food from the mouth into the upper esophagus. It is caused by weakness of tongue muscles.
• Esophageal dysphagia results from difficulty in "transporting" food down the esophagus and may be caused by motility disorders or mechanical obstructing lesions.
• In esophageal cancer we can observe an epigastric mass and palpable supraclavicular lymph node [2].

Mechanical dysphagia
Mechanical dysphagia can be caused by a very large food bolus, intrinsic narrowing, or extrinsic compression of the lumen. When the esophagus cannot dilate beyond 2.5 cm in diameter, dysphagia to normal solid food can occur. Dysphagia is always present when esophagus cannot distend beyond 1.3 cm. Circumferential lesions produce dysphagia more consistently than due lesions that involve only a portion of circumferences of the esophageal wall, as uninvolved segments retain their distensibility.

Abstract
Dysphagia is difficulty in swallowing food semi-solid or solid, liquid, or both. There are many disorder conditions predisposing to dysphagia such as mechanical strokes or esophageal diseases even if neurological diseases represent the principal one. Cerebrovascular pathology is today the leading cause of death in developing countries, and it occurs most frequently in individuals who are at least 60 years old. Patients with dysphagia may walk into dental clinic and because dysphagia is a symptom not a disease, it is a practicing dentist's duty to recognize the underlying cause and then take treatment decisions. Among the most frequent complications of dysphagia are increased mortality and aspiration pneumonia, dehydration, malnutrition, and long-term hospitalization. This review article discusses the pathophysiology, classification, evaluation, investigations and treatment modalities of dysphagia.

Motor dysphagia
Motor dysphagia may result from difficulty in initiating a swallow or from abnormalities in peristalsis and deglutitive inhibition due to disease of the esophageal striated or smooth muscle.

Evaluation of a Case of Dysphagia [1,3-5] History
The oesophagus being inaccessible by palpation the history can provide a presumptive diagnosis in over 80% of patients. b) Gradual-in stricture, malignancy, achalasia, onset after shock or emotional upset common in achabsia (a condition in which the muscles of the lower part of the oesophagus fail to relax, preventing food from passing into the stomach.) c) Intermittent or progressive-a long history, with intermittent symptoms suggests achalasia of cardia, progressive persistency indicates stenotic causes.

Progress is helpful in diagnosing
a) Transient dysphasia may be due to inflammatory. b) Progressive dysphagia lasting a few weeks to a few months is suggestive of cancer oesophagus. c) Episodic dysphagia to solids lasting several years indicates a benign disease characteristic of a lower esophageal ring.

Nature of difficulty in swallowing/Type of distress
a) Type of food difficulty only with solids implies mechanical dysphagia with a lumen that is not severely narrowed.
In advanced obstructive cases dysphagia occurs with liquids and solids. In contrast motor dysphagia due to achalasia and diffuse esophageal spasm is equally affected by solids and liquids from the very onset.
Dysphagia both liquids and solids particularly if there is nasal reflux implies a neurological problem with in coordination of palate. Drooling, difficulty in initiating swallow, nasal regurgitation, difficulty managing secretions, choking, cough episodes, food sticking in the throat all these should alert the dentist into knowing that a neurologists opinion is a must. a) Difficulty in transferring a bolus from mouth to gullet is usually caused by local disorders of pharynx or larynx. b) Sensation of food sticking retrosternally in the throat or at the xiphisternum shortly after swallowing is usually caused by esophageal abnormalities.

Relation of distress to posture
Patients with scleroderma have dysphagia to solids that is unrelated to posture and to liquids while recumbent but not upright. When peptic stricture develops in patients with scleroderma dysphagia becomes more persistents.If distress is at night when patient is in reclining position suggest esophageal heatus hernia.

Position at which food sticks/Site of dysphagia
It gives a fairly accurate guide to the site of obstruction the lesion is either at the level or higher up. (The lesion at or below the perceived location of dysphagia)  c) Regurgitation which is also a feature of pharyngeal pouch may cause cough and recurrent chest infection. Weight loss is a common feature of most disphagias but a short progressive course with history of considerable loss of weight is always suspicious of an oesphegeal cancer which is particularly common in main under 40 who smoke. d) When hoarseness precedes dysphegia, the primary lesions is usually in larynx. Hoarseness following dysphegia may suggest involvement of the recurrent laryngeal nerve by extension of esophageal carcinoma.

Medications
Many medications precipitate dysphagia. These include tetracycline, doxycycline, minocycline, Kcl, quinine, aspirin. Here acute development of retrosternal pain is observed usually exacerbated by swallowing and dysphagia (odynophegia). Immunosuppressive drugs used in cancer chemotherapy may precipitate the fungal esophagitis which may present as dysphgia. Drug reactions like Erythema multiforme or Stevens Johnson syndrome can also cause desquamation and ulceration up to the level of esophagus causing the dysphagia.

Physical Examination
It is important in motor dysphagia due to skeletal muscle, neurologic and oropharyngeal diseases. Signs of bulbar or psuedobulbar palsy including dysarthrthria, dysphonea, ptosis, tongue atrophy and hyperactive jaw jerk in addition to evidence of generalized neuromuscular disease should be sought.
• Mouth and Throat: For stomatitis, malignancy tongue and abnormalities of pharynx.
• Nervous system: For evidence of bulbar paralysis or myasthenia gravis.
• Changes in skin and extremities may suggest a diagnosis of scleroderma and other collagen-vascular diseases or mucocutaneous diseases such as pemphigoid are epidermolysis bullosa, which may involve the esophagus.

Investigation
Dysphagia is nearly always a symptom of organic disease rather than a functional complaint. If oropharyngeal dysphagia is suspected videofluroscopy of oropharyngeal swallowing should be obtained. If mechanical dysphagia is suspected in clinical history barium swallow, esophagogastroscopy and endoscopic biopsies are the diagnostic procedures of choice.