Scleroderma is group of rare connective tissue diseases generally classified as autoimmune rheumatological disorders. Scleroderma comes from the Greek words sclero (hard) and derma (skin). In fact, hardening or tightening of the skin is a common and striking manifestation scleroderma.
Scleroderma results from the overproduction and accumulation of collagen, a connective tissue, in the skin and other body organs like the lungs, kidneys, heart, blood vessels, joints, muscles and gastrointestinal tract. While the cause is not fully understood, there are genetic and environmental factors that play a role in its pathogenesis.
Scleroderma can affect any of the GI organs. It does so by replacing the muscles and nerves that make up the wall of these organs with collagen. This leads to stiffening of the wall, and loss or discoordination of gastrointestinal contractions (motility). Gastrointestinal symptoms depend upon which GI organs are involved. Involvement of the anal sphincter can predispose to fecal incontinence. Scleroderma of the colon might cause diarrhea and/or constipation. Motor dysfunction of the small intestine can lead to stasis of intestinal contents, and overgrowth of bacteria in the small bowel. This produces symptoms of bloating, gas and diarrhea. It can also cause intestinal pseudo-obstruction, which is defined as signs and symptoms of intestinal obstruction without mechanical obstruction. Scleroderma involving the stomach produces gastroparesis, which is failed or very slow gastric emptying of ingested food. The symptoms of gastroparesis include early satiety (filling up quickly), nausea, vomiting and abdominal pain.
Esophageal dysfunction is a common feature of scleroderma. There is a ring of muscle positioned at the junction of the esophagus and stomach (the esophagogastric junction or EGJ) called the lower esophageal sphincter (LES). When swallowing is not occurring it is contracted, closing the EGJ and producing a barrier to the reflux of injurious gastric contents back into the esophagus. Scleroderma patients often have a weak or incompetent LES, which predisposes them to gastroesophageal reflux disease (GERD). Pathological acid reflux frequently produces symptoms of heartburn (a burning sensation in the chest) and/or regurgitation (the unforced return of stomach or esophageal contents to the mouth or throat). Left untreated, GERD can cause esophagitis, esophageal ulceration, esophageal strictures or Barrett's esophagus, which can be a precursor to esophageal cancer. Gastroparesis associated with scleroderma makes GERD worse because the stomach remains filled with noxious materials for a longer time after eating. This prolongs the time over which gastroesophageal reflux can occur. The combination of GERD and gastroparesis can predispose patients to aspiration of gastric contents into the airway, which can be manifest as cough, pneumonia and/or worsening lung function.
Normally, swallowing produces a ring of esophageal contraction called peristalsis, which sweeps swallowed materials down the esophagus and into the stomach. Patients with scleroderma of the esophagus typically lack this peristaltic contraction, which is called aperistalsis. When this occurs, foods, particularly solids, hang up in the esophagus and produce dysphagia (the sensation that food is stuck in the chest). Aperistalsis also worsens GERD because the esophagus cannot clear injurious, refluxed gastric contents back into the stomach. This prolongs the time acid injury can occur in the esophagus.
A number of diagnostic tools are used assess patients with presumed scleroderma of the esophagus and stomach. Alarm symptoms or findings require endoscopic evaluation. These include dysphagia, odynophagia (painful swallowing), nausea and vomiting, anemia, weight loss and blood in the stool. Patients with dysphagia, odynophagia or regurgitation who have no obvious esophageal pathology during endoscopy should have an esophageal manometry. Manometry allows doctors to evaluate function of the esophagus in response to swallowing liquid, viscous solution and solid food. It identifies weakness of the LES, abnormalities of esophageal peristalsis, like aperistalsis, and in some cases abnormalities of pharyngeal function. Patients with heartburn that is not responsive to therapy with medications that inhibit gastric acid production are candidates for esophageal pH testing. There are several techniques to accomplish esophageal pH testing. These tests can confirm the diagnosis of GERD and/or determine if the patient’s therapy is working. It is also important to do a test that determines how well the stomach empties, since GERD is worse in patients with delayed gastric emptying. This is done with a scintigraphic gastric emptying study or a wireless motility capsule study.
Treating the esophageal symptoms of scleroderma can be quite challenging. Medical therapy includes medications that suppress acid production by the stomach (proton pump inhibitors and H2 receptor antagonists), and medications that improve gastric emptying (dopamine antagonists and 5-HT4 receptor agonists). Dietary changes can improve esophageal symptoms. Eating smaller and more frequent meals can help with gastric emptying problems. Not eating or drinking for several hours before bed can decrease the volume of stomach contents when the patient is asleep. This decreases the risk of gastroesophageal reflux and aspiration at night. We put these patients on a low fat and low fiber diet. Fatty/fried foods slow gastric emptying and relax the LES. High fiber foods are more difficult for the stomach to empty. Patients with GERD should avoid caffeine containing foods and chocolate because they contain chemicals called phosphodiesterase inhibitors that relax gastrointestinal muscle. They can weaken esophageal contractions, relax the LES and slow gastric emptying. Alcohol and mints also weaken the GI muscles. We instruct patients with GERD to elevate the head of the bed by 4-6 inches. When GERD symptoms are intractable or complications arise from GERD like worsening lung function, surgical therapy is considered. There are two surgical approaches used in this patient population. A surgery called the Toupet fundoplication improves the barrier to gastroesophageal reflux and roux-en-Y gastric bypass treats both gastric emptying problems and GERD. Taking this approach requires careful patient selection and evaluation.