Introductory Chapter: Gastroesophageal Reflux Disease

Gastroesophageal reflux disease (GERD) occurs frequently in developed countries. The number of cases, in fact, is increasing in the Middle East countries. In western countries, its occurrence ranges from 10 to 20% of the population who may present with typical or atypical symptoms or with complications. Although GERD was described by Asher Winkelstein, an American gastroenterologist, in 1935, it had appeared among patients earlier than that time. Nowadays, cases of GERD are common among obese individuals, patients with gallbladder disease, and those individuals under stress. It has also become a common clinical problem that commonly affects young adults, both male and female, of 40 years old.


Introduction
Gastroesophageal reflux disease (GERD) occurs frequently in developed countries. The number of cases, in fact, is increasing in the Middle East countries. In western countries, its occurrence ranges from 10 to 20% of the population who may present with typical or atypical symptoms or with complications. Although GERD was described by Asher Winkelstein, an American gastroenterologist, in 1935, it had appeared among patients earlier than that time. Nowadays, cases of GERD are common among obese individuals, patients with gallbladder disease, and those individuals under stress. It has also become a common clinical problem that commonly affects young adults, both male and female, of 40 years old.

History of GERD
1855-Bowditch Rokitansky reported that esophagitis was due to gastroesophageal reflux. Allison and Barrett found the association between hiatus hernia and gastroesophageal reflux.
1828-Charles Millard in Paris noticed the first case of esophagitis in child. 1879-Heinrich Quincke reported that ulceration in the esophagus was due to gastroesophageal reflux.
1906-Tilston described the typical symptoms of esophagitis. 1920-Joseph Sheehan described the endoscopic findings of esophagitis. 1921-Porter Vinson noted the association between stricture and esophagitis. 1934-Hampel introduced the term peptic esophagitis. 1956-Rudolf Nissen performed a successful fundoplication for patient, who suffered from GERD, with hiatus hernia. Patient was cured from the complaint.

Anatomy and Physiology
At the lower end of the esophagus is a sphincter which is formed by a change in the muscles of the esophagus. This sphincter controls the flow of esophageal contents to the stomach. Different factors related to the anatomy and physiology of the sphincter prevent the reflux of gastric contents into the esophagus. Among these factors include the following: 1. High pressure zone: Pressure at the lower esophageal sphincter area is high than stomach pressure (gastric pressure is +4 to +6, at the lower esophageal sphincter is +24 mmgh, and in the thoracic esophagus is −6). Because of the high

Atypical symptoms
Atypical symptoms are those where the patient will present with symptoms not related to gastrointestinal system: coughing, wheezing, recurrent pharyngitis, laryngitis, and chest pain. Its acute onset may resemble acute myocardial infarction.
Patient may present with complicated gastroesophageal reflux diseasesome symptoms include the following: stricture, Barrett esophagus, lung damage in the form of pneumonia, and lung fibrosis if condition goes chronic.  (Figure 1). Esophagitis will be experienced by 50% of patients with GERD. It can also diagnose Barrett esophagus and esophageal peptic stricture (Figure 2).

Contrast barium study:
It is applied to detect hiatal hernia and esophageal stricture [8]. Barium contrast study can show hiatus hernia which can be small or large sac (Figures 3-5).
3. PH monitoring: 24 pH monitoring is very important in atypical presentation of gastroesophageal reflux disease [9, 10]. It can confirm or exclude the disease, with a diagnostic rate of 70-90%. It is not indicated in patients with esophagitis. 4. Gastroesophageal scintigraphy: Where drink like orange juice or milk is labeled with technetium and is used to study reflux, this test is rarely used for diagnosis of GERD. It is used in small children where we can study the reflexate to the lung, and the test is easy in small babies in comparison to other invasive tests. Gastroesophageal scintigraphy is used for patient who presents with atypical reflux symptoms like recurrent upper respiratory symptoms.   5. Multichannel impedance pH monitoring: It is a gold standard technique for diagnosis of GERD; it is more superior and more sensitive in diagnosing GERD than usual pH monitoring.  6. Manometry: It is a very important investigation to exclude motility disorders like achalasia and is indicated in patient who presents with atypical symptoms of gastroesophageal reflux disease. High-resolution manometry is more sensitive and superior than ordinary manometry in diagnosing esophageal motility disorders.

Treatment
Reasons for treating GERD: 1. Heart burn is a troubling symptom and affects patient life.
2. Complications of GERD may cause esophagitis which will result to bleeding. Predisposition to Barrett esophagus that may turn to malignancy is 40-60 times seen in patient with reflux esophagitis-induced Barrett [11-13]. c. Avoid drugs which reduce the tone of sphincter.

Medical
Medical treatment where drugs are used to neutralize the effect of the reflux on esophageal mucosa: a. Antacids: Drugs that will neutralize the acid effect include the following-calcium, aluminum, and magnesium compounds. These are best taken after meals. Their effect is brief; and once they get emptied from the stomach, the symptoms may come back. These need to be given on an hour base to neutralize the acid effect.
b. Histamine antagonists: There are receptors on the acid-producing cells which are stimulated by histamine to produce acid. These receptors are blocked by histamine-blocking drugs which act on H2 receptors. These drugs are best taken before meals. These include cimetidine which can be given 400-800 mg daily, ranitidine given 150 mg twice daily, and famotidine given 20-40 mg twice daily.

Surgery
Indication of surgery: 1. Failure of medical treatment.
2. Development of complications of the drugs.
4. Atypical presentation with positive 24 h pH records.
5. Patients do not like to take drug for long life to control the symptoms.

Surgery for GERD
It can be done by lengthening the lower esophageal sphincter to create valve-like action to prevent refluxing of gastric contents in the esophagus. Procedure is done by wrapping the stomach around the lower esophagus [18][19][20], either full wrap of 360° (which is named after Nissen) or partial wrap of 270°, either done posteriorly or anteriorly.
Fundoplication was previously performed by open surgery. Nowadays, most operations are done laparoscopically (Figures 6 and 7), with excellent outcome on short-term and long-term follow-ups.
Patient will stop taking the drugs. All patients should be seen by gastroenterologist, ENT specialist, and surgeons before surgery, especially for those patients who come with atypical symptoms of GERD.
For many years, open surgery has been used for hiatus hernia but was rarely applied for GERD without hernia. Many operations can be done, either abdominal approach or thoracic approach. The common operation is the Nissen fundoplication which has been used since 1950, with a success rate of 80-90%. Its complication rate ranges from 10 to 15% and includes difficulty in swallowing and flatulence which may go for some time than ease off.

Esophageal magnet ring
It is a new technique where there is no need to make wrapping around the lower esophagus by the stomach. This is a magnet ring fixed around the lower esophagus [31,32]. It is not widely used and still under trial where magnet ring is fixed laparoscopically around the esophageal sphincter. It moves out once food comes in, and it comes back when the food enters the stomach. It has benefit over Nissen fundoplication. The patient can belch, vomit, and have no gas bloat syndrome, and it is reversible. The technique, however, is still under long-term trials.