Oculogastrointestinal Muscular Dystrophy

Very rare form of muscular dystrophy that affects females more often than males. Clinically, patients present with ptosis, external ophthalmoplegia, and absence of intestinal peristalsis, leading to abdominal pain, diarrhea, constipation, malabsorption, and progressive intestinal pseudoobstruction.

Intestinal Pseudoobstruction with External Ophthalmoplegia Syndrome; Familial Visceral Myopathy with Ophthalmoplegia.

Described for the first time in 1983 by V. Ionasescu and S. Anuras.

Rare.

Autosomal recessive.

Primary myopathic lesions affect the smooth muscles (musculi propria) of the stomach, jejunum, and colon, while the neurogenic structures (vagus nerve and myenteric plexus) are intact. This disorder leads to progressive intestinal pseudoobstruction with malnutrition. Ocular manifestations, such as ptosis and ophthalmoplegia, are associated with the disorder because of occasional myopathic changes (atrophy) of the striated muscles and involvement of the peripheral nerves and central nervous system, characterized by demyelinating and axonal neuropathy and focal spongiform degeneration of the posterior columns.

Early onset is characterized by ptosis and ophthalmoplegia during childhood, gastrointestinal symptoms in teenage and early adulthood years; death occurs before age 30 years. Late onset has a milder course with ocular and gastrointestinal manifestations during the fourth and fifth decades of life. Jejunal manometry, gastrointestinal contrast roentgenograms (gastric atony with delayed gastric emptying, hypomotility and dilatation of the small bowel with jejunal and ileal diverticula, megaduodenum, possibly megacolon), and gastrointestinal biopsy (degeneration and fibrosis of the intestinal muscle involving mainly the longitudinal layer) contribute to the final diagnosis. In cases of associated muscular weakness, electromyography shows delayed motor nerve conduction velocities, and sural nerve biopsy may reveal loss of large myelinated fibers and axonal loss. Striated muscle biopsies show myopathic changes involving both fiber types. Creatine kinase levels are often normal.

Bilateral ptosis and external ophthalmoplegia (limitation of eye movements in all directions) are associated with gastrointestinal manifestations of chronic diarrhea and symptoms of chronic intestinal pseudoobstruction leading to malnutrition. Some cases of associated neuromuscular impairment (facial, proximal, and distal limbs weakness with decreased deep tendon reflexes, limb hypesthesia) have been described. Mitral valve prolapse may coexist. The main differential diagnosis is oculopharyngeal muscular dystrophy, which consists of an autosomal dominant transmission, ptosis, and ophthalmoplegia. The digestive tract involvement consists only of difficulty in swallowing (no gastrojejunal lesions) or a mitochondrial disease-like myopathy with peripheral neuropathy, encephalopathy, and gastrointestinal disease (MNGIE Syndrome).

Obtain a full history of gastrointestinal symptoms, “early” versus “late” onset of the disease, associated neuromuscular manifestations, and/or mitral valve prolapse (echocardiogram). Evaluate patient's volume status, electrolyte levels, and obtain a hemoglobin level. If on total parenteral nutrition (TPN), evaluate albumin, glucose, phosphate, calcium, and magnesium levels as well as liver function tests. Muscular weakness seems to affect mainly the limbs (no respiratory muscle weakness reported).

Optimization of fluid status must be achieved. High risk of pulmonary aspiration mandates a rapid-sequence induction (if associated myopathy, use nondepolarizing muscle relaxant). The intraoperative ...