Immune system and microbiome in the esophagus: implications for understanding inflammatory diseases

The gastrointestinal tract is susceptible to various disorders. If the lower esophageal sphincter is damaged, stomach acid can flow back into the esophagus, causing irritation and inflammation of the lining. This condition is called gastroesophageal reflux disease (known as heartburn) and may cause chest pain and difficulty swallowing. In the stomach, prolonged use of nonsteroidal anti-inflammatory drugs like aspirin, chronic alcohol consumption, bacterial infections such as Helicobacter...

Irritable Bowel Syndrome (IBS) is characterized by functional disturbances in the gastrointestinal system, presenting a cluster of symptoms without evident structural or biochemical abnormalities. It primarily affects the large intestine and may cause abdominal pain, bloating, excessive gas, diarrhea, constipation, or both.
IBS is a chronic condition that can persist over a long period or recur frequently.
The pathogenesis of IBS involves a complex interplay of the following factors:
Altered...

Esophageal strictures involve abnormal narrowing or tightening of the esophagus. They vary in length and severity, ranging from mild constriction to complete obstruction, and are classified as benign (noncancerous) or malignant (cancerous).
Etiology
The primary cause of esophageal strictures is long-standing gastroesophageal reflux disease (GERD), accounting for about 70 to 80% of adult cases. Chronic acid reflux can lead to injury and scarring of the esophageal lining, culminating in...

The human body contains a monogastric digestive system. In a monogastric digestive system, the stomach only contains one chamber in which it digests food. Several other animal species also have monogastric digestive systems, including pigs, horses, dogs, and birds. This chapter, however, focuses on the human digestive system.

Gastroesophageal Reflux Disease (GERD) involves the recurrent backflow of the stomach or duodenal contents into the esophagus, leading to troublesome symptoms and potential esophageal mucosal damage. Although GERD is often referred to as a disease, it is more accurately described as a syndrome, as it encompasses a range of symptoms and complications rather than a singular pathological entity, impacting a large number of individuals as the most prevalent upper gastrointestinal problem. Roughly...

Barrett's esophagus is a medical condition where the esophageal mucosa is significantly damaged by stomach acid or other digestive fluids, often due to long-term exposure associated with gastroesophageal reflux disease (GERD). In GERD, a weakened or abnormally relaxed lower esophageal sphincter allows stomach acid to flow persistently into the esophagus.
This constant acid exposure transforms the esophagus's pink mucosal lining (stratified squamous epithelium) into a type of lining more...