<unk>  or Distal esophageal<unk>  <unk>  is an uncommon esophageal motility disorder causing chest pain and/or dysphagia.<unk>  was first<unk> cribed by Osgood, in 1889 in 6 patients presenting with chest pain and dysphagia. Creamer et al. (1958) made the first manometric<unk> criptions of<unk> . Development of high resolution esophageal manometry in 2000 has led to classification of esophageal motility disorders.<unk>  can be classified as primary or secondary based on presence or absence of other disease associated with it. The exact pathogenesis of<unk>  is not fully understood. Current high-resolution manometric studies suggests impairment of inhibitory neurons. These inhibitory neurons use nitric oxide (NO) as neurotransmitter. Exact cause of<unk>  is unknown. However, may be caused by consequence of various diseases and secondary to conditions like compression of nerves within esophageal wall, inflammation of the esophagus, stricture, GERD, psychological conditions like anxiety or depression.<unk>  must be differentiated from other diseases that cause dysphagia, chest pain and weight loss such as angina, reflux esophagitis, esophageal carcinoma, systemic sclerosis, nutcracker esophagus, hypertensive LES, esophageal web/stricture, pseudoachalasia, stroke, esophageal candidiasis, Chagas disease etc. Common risk factors in the development of<unk>  include: Age (60-80 years), obesity, mitral valve prolapse, presence of GERD, Hypertension, anxiety or depression, and drinks (eg. red wine, very hot or cold liquid or fluid). If left untreated, most patients  are symptom free over the course of time. Very few cases report of progression to achalasia and nut cracker esophagus. The diagnostic study of choice for<unk>  is manometry. An x-ray of esophagus after barium swallow (esophagogram) is the next best test to support manometric diagnosis. The mainstay of treatment for<unk>  is medical therapy with calcium channel blockers, and/or tricyclic antidepressants.
Diffuse esophageal spasm
Achalasia
Esophageal candidiasis
Nutcracker esophagus
Esophageal stricture
Eosinophilic esophagitis
Barrett's esophagus
Esophageal web