Esophageal Diseases

1. Esophageal Diseases MJ. Farahvash M.D. Associate Professor of Medicine

3. Diseases of the Esophagus Two major functions of the esophagus are transport of food bolus from the mouth to the stomach and prevention of retrograde flow of gastrointestinal contents. Esophageal transport function begins with the transfer of food from the mouth and pharynx through the opened upper esophageal sphincter (UES) into the esophagus, and it involves esophageal peristalsis and relaxation of the lower esophageal sphincter (LES). Retrograde flow from the stomach into the esophagus is prevented by the LES and from the esophagus into the pharynx by the UES.

4. Peristalic contraction in response to a swallow is called primary peristalsis. Local distention of the esophagus from food activates intramural reflexes in the smooth muscle and results in secondary peristalsis, which is limited to the thoracic esophagus. Tertiary contraction are nonperistaltic because they occur simultaneously over a long segment of the esophagus. Tertiary contractions may occur in response to a swallow or esophageal distention, or they may occur spontaneously.

7. Dysphagia A sensation of sticking or obstruction of the passage of food through the mouth, pharynx, or esophagus. Aphagia Complete esophageal obstruction, which is usually due to bolus impaction and represents a medical emergency Odynophagia Painful swallowing Globus pharyngeous The sensation of a lump lodged in the throat

8. Misdirection of food Resulting in nasal regurgitation and laryngeal and pulmonary aspiration of food during swallowing, is characteristic of oropharyngeal dysphagia Phagophobia Fear of swallowing, and refusal to swallow may occur in hysteria, rabies, tetanus, and pharyngeal paralysis due to fear of aspiration

9. Normally, the LES relaxes in association with esophageal peristalsis with swallowing. However, relaxation of the LES without esophageal peristalsis may occur during belching and gastric distention. Gastric distention–evoked transient lower esophageal sphincter relaxation (tLESR) is a vagovagal reflex. Reflex LES relaxation is augmented by phosphodiesterase-5 inhibitors such as sildenafil that increase cyclic guanosine monophosphate (cGMP) in the sphincter muscle, and it is inhibited by GABA-B agonists such as baclofen.

10. Fatty meals, smoking, and beverages with high xanthine content (tea, coffee, cola) also cause a reduction in sphincter pressure. Many hormones and neurotransmitters can modify LES pressure. Muscarinic M2 and M3 receptor agonists, -adrenergic agonists, gastrin, substance P, and prostaglandin F2 all cause LES contraction. On the other hand, nicotine, -adrenergic agonists, dopamine, cholecystokinin, secretin, vasoactive intestinal peptide (VIP), calcitonin gene–related peptide, adenosine, prostaglandin E, nitric oxide donors such as nitrates, and inhibitors of phosphodiesterase 5 reduce LES pressure.

11. Heartburn Heartburn, or pyrosis, is characterized by burning retrosternal discomfort that may move up and down the chest like a wave. When severe, it may radiate to the sides of the chest, the neck, and the angles of the jaw. Heartburn is a characteristic symptom of reflux esophagitis and may be associated with regurgitation or a feeling of warm fluid climbing up the throat. It is aggravated by bending forward, straining, or lying recumbent and is worse after meals. It is relieved by an upright posture, by the swallowing of saliva or water, and, more reliably, by antacids. Heartburn is produced by heightened mucosal sensitivity and can be reproduced by infusion of dilute (0.1 N) hydrochloric acid (Bernstein test) or neutral hyperosmolar solutions into the esophagus.

12. Odynophagia, or painful swallowing, is characteristic of nonreflux esophagitis (particularly monilial), herpes, and pill-induced esophagitis. Odynophagia may occur with peptic ulcer of the esophagus (Barrett's ulcer), carcinoma with periesophageal involvement, caustic damage of the esophagus, and esophageal perforation.

13. Esophageal chest pain resembling cardiac pain is called noncardiac chest pain or atypical chest pain. Such pain is different from heartburn or odynophagia, and it may occur in gastroesophageal reflux disease (GERD) or esophageal motility disorders such as diffuse esophageal spasm (DES). Coronary artery disease should always be excluded before the esophagus is considered as the origin of atypical chest pain. The most frequent esophageal cause of chest pain is reflux esophagitis.

14. A trial of proton pump inhibitors (PPIs); Motility study may be useful in these cases. A large number of these patients are thought to have esophageal hypersensitivity syndrome. A low-dose antidepressant treatment may be helpful in these cases. Many of these patients also have behavioral and psychosomatic disorders such as depression, anxiety, or panic reactions.

15. Fatty meals, smoking, and beverages with high xanthine content (tea, coffee, cola) also cause a reduction in sphincter pressure.

16. Many hormones and neurotransmitters can modify LES pressure. Muscarinic M2 and M3 receptor agonists, -adrenergic agonists, gastrin, substance P, and prostaglandin F2 all cause LES contraction.

17. Reduce LES Pressure Nicotine, -adrenergic agonists, dopamine, cholecystokinin, secretin, vasoactive intestinal peptide (VIP), calcitonin gene–related peptide, adenosine, prostaglandin E, nitric oxide donors such as nitrates, and inhibitors of phosphodiesterase 5.

18. Regurgitation Regurgitation is the effortless appearance of gastric or esophageal contents in the mouth. In distal esophageal obstruction and stasis, as in achalasia or the presence of a large diverticulum, the regurgitated material consists of tasteless mucoid fluid or undigested food. Regurgitation of sour or bitter-tasting material occurs in severe gastroesophageal reflux and is associated with incompetence of both the UES and the LES.

19. Regurgitation 2 Regurgitation may result in chronic cough, laryngitis, and laryngeal aspiration, with spells of coughing and choking that may awaken the patient from sleep. It may also result in aspiration pneumonia. In some patients, regurgitation and rumination may be a behavioral problem.

20. Water brash Water brash is reflex salivary hypersecretion that occurs in response to peptic esophagitis and should not be confused with regurgitation.

21. Radiologic Studies Barium swallow with fluoroscopy and an esophagogram is often used to evaluate both structural and motor disorders and is the initial test of choice in the motility disorders. Videofluoroscopic swallow study focuses on oral and pharyngeal phases of swallowing A finding of spontaneous reflux of barium from the stomach into the esophagus as an indicator of gastroesophageal reflux is unreliable. A barium-soaked piece of bread or a 13-mm barium tablet is sometimes used to demonstrate an obstructive lesion.

22. CT examination of the chest may be helpful in assessing the esophageal wall and the structures surrounding the esophagus.

26. Endoscopic Ultrasound EUS combine and endoscope with an ultrasound. Create a transmural image all the tissue surrounding the endoscope tip. Major esophageal applications of EUS are to stage esophageal cancer, to evaluate dysplasia in Barrett’s esophagus, and to asses submucosal tumors.

29. Esophagoscopy Esophagoscopy is the direct method of establishing the cause of mechanical dysphagia. It can identify mucosal lesions that may not be revealed by the usual barium swallow. Ultrathin endoscopes have been used when the lumen is markedly narrowed; on occasion, a stricture must be dilated before the examination can be completed. Endoscopic biopsies are useful in diagnosing carcinoma, esophagitis, and other mucosal diseases such as eosinophilic esophagitis. Cells obtained by a cytology balloon or by brushing the mucosa can be evaluated for carcinoma. Endoscopic ultrasonography permits evaluation of intramural and periesophageal masses and staging of esophageal cancer.

30. Esophageal Motility The study of esophageal motility entails simultaneous recording of pressures from different sites in the esophageal lumen with an assembly of pressure sensors positioned 5 cm apart. The UES and LES appear as zones of high pressure that relax on swallowing. The esophagus normally shows peristaltic waves with each swallow.

31. Esophageal motility studies are helpful in the diagnosis of esophageal motor disorders (achalasia, spasm, and scleroderma) but are of little value in the differential diagnosis of mechanical dysphagia. In patients with reflux esophagitis, esophageal manometry is useful in quantifying LES competence and providing information on the status of the esophageal body motor activity. Manometry provides quantitative data that cannot be obtained by barium swallow or endoscopy.

34. Esophageal impedance testing identifies the nature (fluid or gas) and the direction of movement (oral or aboral) by measuring impedance across segments using a special catheter positioned in the esophagus. It may be helpful in the study of transit of the contents, particularly nonacid gastric contents.

35. tLESR vs swallow associated LESR

36. Achalasia Achalasia is a motor disorder of the esophageal smooth muscle and involves thoracic and abdominal parts of the esophagus. In achalasia, the esophageal body loses peristaltic contractions and the LES does not relax normally in response to swallowing.

38. Pathophysiology The underlying abnormality is the loss of intramural neurons. Inhibitory neurons containing VIP and nitric oxide synthase are predominantly involved, but cholinergic neurons are also affected in advanced disease. Primary idiopathic achalasia accounts for most of the cases seen in the United States. Secondary achalasia may be caused by gastric carcinoma that infiltrates the esophagus, lymphoma, Chagas' disease, certain viral infections, eosinophilic gastroenteritis, and neurodegenerative disorders.

39. Clinical Features Achalasia affects patients of all ages and both sexes. Dysphagia, chest pain, and regurgitation are the main symptoms. Dysphagia occurs early with both liquids and solids and is worsened by emotional stress and hurried eating. Various maneuvers designed to increase intraesophageal pressure, including the Valsalva maneuver, may aid the passage of the bolus into the stomach. Regurgitation and pulmonary aspiration occur because of retention of a large amount of saliva and ingested food in the esophagus. Patients may complain of difficulty belching.

40. The presence of gastroesophageal reflux argues against achalasia; in patients with long-standing heartburn, cessation of heartburn and appearance of dysphagia may suggest development of achalasia, peptic stricture, or carcinoma on top of reflux esophagitis. The course is usually chronic, with progressive dysphagia and weight loss over months to years. Achalasia associated with carcinoma is characterized by severe weight loss and a rapid downhill course.

41. Diagnosis A chest x-ray shows absence of the gastric air bubble and sometimes a tubular mediastinal mass beside the aorta. An air-fluid level in the mediastinum in the upright position represents retained food in the esophagus. Barium swallow shows esophageal dilation, and in advanced cases the esophagus may become sigmoid. On fluoroscopy with barium swallow, normal peristalsis is lost in the lower two-thirds of the esophagus. The terminal part of the esophagus shows a persistent beaklike narrowing representing the nonrelaxing LES

43. Manometry shows the basal LES pressure to be normal or elevated, and swallow-induced relaxation either does not occur or is reduced in degree, duration, and consistency. The esophageal body shows an elevated resting pressure. In response to swallows, primary peristaltic waves are replaced by simultaneous contractions. These contractions may be of poor amplitude (classic achalasia) or of large amplitude and long duration (vigorous achalasia).

47. Cholecystokinin (CCK), which normally causes a fall in the sphincter pressure, paradoxically causes contraction of the LES (the CCK test). This paradoxical response occurs because, in achalasia, the neurally transmitted inhibitory effect of CCK is absent and the direct excitatory effect of CCK remains unopposed. Endoscopy is helpful in excluding the secondary causes of achalasia, particularly gastric carcinoma.

48. Achalasia: Treatment Nitroglycerin, 0.3–0.6 mg, is used sublingually before meals and as needed for chest pain. Isosorbide dinitrate, 2.5–5 mg sublingually or 10–20 mg orally before meals, can also be used. Nitrates are associated with headache and postural hypotension. The calcium channel blocker nifedipine, 10–20 mg orally or sublingually before meals, may be effective. Sildenafil provides symptomatic relief by increasing cGMP that may reduce LES pressure and augment swallow-induced relaxation.

49. Botulinum toxin acts by blocking cholinergic excitatory nerves in the sphincter. Endoscopic intrasphincteric injection of botulinumtoxin is effective with clinical improvement in 60% of patients at 6 months; it may be very useful in temporizing symptoms in elderly or high-risk patients. However, repeated injections may lead to fibrosis, complicating further operative therapy. Balloon dilatation reduces the basal LES pressure by tearing muscle fibers. In experienced hands, this technique is effective in ~85% of patients; perforation and bleeding are potential complications.

50. Heller's extramucosal myotomy of the LES, in which the circular muscle layer is incised, is equally effective. Laparoscopic myotomy is currently the procedure of choice. Since reflux esophagitis and peptic stricture may follow after a successful treatment (more often with myotomy than with balloon dilatation), surgical myotomy is sometimes accompanied by partial fundoplication to lessen postoperative reflux.