IDIOPATHIC MUSCULAR HYPERTROPHY OF THE OESOPHAGUS AS A CAUSE OF PROGRESSIVE DYSPHAGIA AND OESOPHAGEAL OBSTRUCTION

Idiopathic muscular hypertrophy of the oesophagus (IMHO) is a rare disorder of uncertain aetiology which results in oesophageal motordysfunction. Clinical manifestations depend on the severity of musclethickening. IMHO has overlapping morphological features withDiffuse Oesophageal Leiomyomatosis (DOL), these include thepattern of muscle thickening and often the presence of mural eosi-nophilic infiltrate. The two conditions occur in different age groupsand the latter often has extra-oesophageal manifestations.We describe a 64-year-old man presenting with progressive,severe dysphagia and substantial weight loss, which requiredfeeding gastrostomy. Endoscopic ultrasonography examinationshowed thickening of the main muscle coat and video assistedmediastinoscopy showed an abnormally thickened oesophagus, withbundles of cytologically bland smooth muscles present in the biop-sied material. The patient underwent oesophagectomy and resectionof the abnormal segment of the lower oesophagus. This 16 cmsegment of oesophagus showed a massive diffuse thickening ofpredominantly circumferential muscle layer with mural eosinophilicinfiltrate which spared the squamous mucosa. The myenteric plexusand vessels appeared normal.IMHO is difficult to diagnose clinically, radiologically or endoscopi-cally and malignancy can only be excluded with confidence after thelesion has been resected and subjected to complete histologicalexamination.