Swallowing is the function of the pharynx, larynx, and esophagus. This function may be impaired by two mechanisms: mechanical obstruction (e.g., carcinoma of the esophagus) and physiologic obstruction (e.g., pseudobulbar palsy).
Mechanical obstruction may result from intrinsic disease of the pharynx, larynx, and esophagus or extrinsic disease of the organs around the esophagus.
The mnemonic VINDICATE is useful in recalling the causes of mechanical obstruction as follows:
· V—Vascular indicates aortic aneurysms and cardiomegaly.
· I—Inflammatory should suggest pharyngitis, tonsillitis, esophagitis, and mediastinitis.
· N—Neoplasm should bring to mind esophageal and bronchogenic carcinoma, and dermoid cysts of the mediastinum.
· D—Degenerative and deficiency disease should suggest Plummer–Vinson syndrome of iron deficiency anemia.
· I—Intoxication immediately indicates lye strictures.
· C—Congenital and acquired anomalies should suggest esophageal atresia and diverticula.
· A—Autoimmune disease suggests scleroderma.
· T—Trauma would prompt the recall of ruptured esophagus, pulsion diverticulum, and foreign bodies that obstruct or injure the wall of the esophagus.
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TABLE 23. Diarrhea–Physiologic Classification |
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Physiologic obstruction results from neuromuscular disorders at the end organ, myoneural junction, and lower and upper motor neurons.
1. End organ. This should suggest myotonic dystrophy, dermatomyositis, achalasia, and diffuse esophageal spasm.
2. Myoneural junction. This brings to mind myasthenia gravis.
3. Lower motor neuron. In this category one would recall poliomyelitis, diphtheritic polyneuritis, and brainstem tumors or infarctions.
4. Upper motor neuron. This structure prompts the recall of pseudobulbar palsy from cerebral thrombosis, embolism, or hemorrhage, multiple sclerosis, presenile dementia, and diffuse cerebral arteriosclerosis. It should also bring to mind Parkinson disease and other extrapyramidal disorders.
Approach to the Diagnosis
The age of onset is significant because carcinoma of the esophagus is rare before age 50, whereas achalasia and reflux esophagitis are more common in young and middle-aged adults. The onset is gradual in carcinoma and aortic aneurysms but more acute in reflux esophagitis and foreign bodies. Patients with achalasia have trouble swallowing both food and water, but those with carcinoma suffer the most, and often the only difficulty is swallowing food.
Association of other symptoms and signs is important. Neurologic findings will focus on the diagnosis of bulbar and pseudobulbar palsy whereas hematemesis and heartburn will suggest esophageal carcinoma or reflux esophagitis.
The barium swallow is still the most useful initial study to order. However, esophagoscopy and biopsy will lead to a definitive diagnosis in most cases of mechanical obstruction. If esophagoscopy is negative, one may resort to a mecholyl test to diagnose achalasia, a Tensilon test to exclude myasthenia gravis, and esophageal manometry to diagnose reflux esophagitis, scleroderma, and diffuse esophageal spasm.
Other Useful Tests
1. CBC (Plummer–Vinson syndrome)
2. ANA analysis (collagen disease)
3. Sonogram (laryngeal obstruction)
4. Videofluoroscopy (oropharyngeal obstruction)
5. Ambulatory pH monitoring (reflux esophagitis)
6. CT scan of the mediastinum (mediastinal mass, aortic aneurysm)
7. Gastroenterology consult
8. Therapeutic trial of proton pump inhibitor (reflux esophagitis)
9. Solid food scintigraphy (Achalasia)