Spastic paraplegia 9- autosomal dominant
Overview
Spastic paraplegia 9, autosomal dominant: A rare disorder characterized by muscle wasting and weakness mainly in the legs, short stature, skeletal abnormalities and cataracts.
Symptoms
Cataracts Short stature Skeletal abnormalities Gastroesophageal reflux Leg weakness
Causes
The function of the LES — a high-pressure area in the lower esophagus, just above the stomach — is to prevent gastric contents from backing up into the esophagus. Normally, the LES creates pressure, closing the lower end of the esophagus, but relaxes after each swallow to allow food into the stomach. Reflux occurs when LES pressure is deficient or when pressure within the stomach exceeds LES pressure. (See Influences on LES pressure, page 690.) Studies have shown that a patient with symptom-producing reflux can’t swallow often enough to create sufficient peristaltic amplitude to clear gastric acid from the lower esophagus. This results in prolonged periods of acidity in the esophagus when reflux occurs. Predisposing factors include: ❑ pyloric surgery (alteration or removal of the pylorus), which allows reflux of bile or pancreatic juice ❑ long-term nasogastric (NG) intubation (more than 4 days) ❑ any agent that lowers LES pressure, such as food, alcohol, cigarettes; anticholinergics (atropine, belladonna, and propantheline); or other drugs (morphine, diazepam, calcium channel blockers, and meperidine) ❑ hiatal hernia with an incompetent sphincter ❑ any condition or position that increases intra-abdominal pressure, such as straining, bending, coughing, pregnancy, obesity, and recurrent or persistent vomiting. About 25% to 40% of Americans experience symptomatic GERD at some point in their lives, while 7% to 10% of Americans experience symptoms on a daily basis. True incidence figures may be even higher because many people with GERD take over-the-counter remedies without reporting their symptoms.