Introduction:
The body constantly undergoes changes to adapt to different kinds of stress and conditions, which may be beneficial or harmful to the body. The body is made up of various types of cells, each specific to an organ or tissue. A group of cells performing similar functions are called tissues. The cells in the body can be classified into different types based on their shape as squamous (flat), cuboidal (square), and columnar (tall) cells.
Columnar cells are found in organs like the breast, stomach, and other sites. These cells tend to undergo certain changes in response to an external stimulus. The most commonly observed change is in the esophageal lining, which is columnar cell metaplasia (the ability of a cell to differentiate into any cell). These changes can predispose to cancer if left undiagnosed or untreated for a while. Hence, it is essential to know the symptoms and causes and monitor the changes in the esophagus to lead a healthy life.
What Is Epithelium?
The epithelium is an avascular (lack of blood supply) tissue composed of different types of cells. Cells are the building blocks of living organisms. Epithelium also forms the secretory portion of the glands. Glands are organs that make secretory substances like hormones, sweat, digestive juices, tears, or saliva. In addition, specialized epithelial cells function as receptors for special senses like smell, taste, hearing, and vision.
What Are the Functions of Epithelium?
The epithelium has several functions that are listed below:
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Diffusion:
Diffusion is the movement of molecules from a higher concentration to a lower concentration.
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Excretion:
Excretion is the disposal of waste from the body. The epithelium in the kidneys and sweat glands help to excrete waste and sweat, respectively.
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Absorption:
The epithelial lining in the internal organs helps in the absorption of nutrients required for the body.
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Protection:
The epithelial tissue lining the intestine protects other parts of the body from intestinal bacteria.
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Secretion:
The epithelium in the glands helps to secrete hormones, enzymes, and fluids.
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Filtration:
The epithelial tissue in the kidneys helps to filter waste products from the blood.
What Is the Classification of Epithelial Cells?
The epithelial cells classified based on their shape include:
1) Squamous Cells:
Squamous cells are composed of flat and irregularly shaped cells. It is also referred to as pavemented epithelium. Squamous cells are commonly found in:
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Inner and middle ear.
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Pulmonary alveoli (tiny air sacs present within the lungs).
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Loop of Henle (U-shaped tube found in kidneys).
2) Cuboidal Cells:
In cuboidal cells, the width and height of the cells are approximately the same. Cuboidal cells are commonly found in:
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Kidney tubules.
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Thyroid follicles.
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The surface of the ovary.
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Ducts of the exocrine gland (secrete substances through ducts).
3) Columnar Cells:
The columnar cells are tall cells with increased height and decreased width. The columnar cells are usually arranged in a single layer. The columnar cells are commonly found in:
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Small intestine.
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Colon.
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The inner lining of the stomach.
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Gallbladder.
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Esophagus.
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Breast.
What Are the Types of Columnar Cells?
The columnar epithelium is classified as:
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Ciliated Columnar Epithelium:
The ciliated columnar epithelium has hair-like projections called cilia. Cilia is mainly involved in motile (moving) activity. It helps to move cells and materials. It is usually present in the lungs, ears, and respiratory tract. They keep the airways clear of dirt and aid in breathing well.
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Goblet Cells:
Goblet cells are modified forms of columnar epithelial cells. They help to synthesize and secrete mucin. Mucin is molecules present abundantly in mucus, which are gel-like secretions that provide lubrication to cells. These cells are scattered among other cells in the respiratory and gastrointestinal tract.
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Pseudostratified Columnar Epithelium:
Pseudo refers to false, and stratified refers to layers. The pseudostratified columnar epithelial cells consist of a single layer of cells with the nucleus at different levels. Hence, it creates the illusion of stratification.
What Is Metaplasia?
Metaplasia is the reversible change of cells, in which a cell type is replaced by another group of cells that are not commonly found in that particular tissue.
What Is Columnar Cell Metaplasia?
In columnar cell metaplasia, the columnar cells undergo metaplastic changes, which commonly occur in Barrett's esophagus.
What Is Barrett’s Esophagus?
Barrett’s esophagus was initially reported by Norman Barrett. It is also called columnar epithelium-lined lower esophagus (CELLO). It refers to the metaplastic (abnormal) changes in the cells of the lower portion of the esophagus. In Barrett’s esophagus, the squamous epithelial cells lining the esophagus are replaced by metaplastic columnar epithelial cells that predispose to cancer.
What Are the Causes of Barrett’s Esophagus?
Barrett’s esophagus is an adaptation to chronic acid exposure from reflux esophagitis. Reflux esophagitis is the inflammation of esophageal mucosa. The other cause of Barrett’s esophagus is gastroesophageal reflux disease (GERD). GERD is characterized by stomach acids flowing back into the esophagus (connecting tube between mouth and esophagus), causing irritation to the esophageal lining.
What Are the Signs and Symptoms of Barrett’s Esophagus?
The commonly associated symptoms with Barrett’s esophagus are:
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Dysphagia (trouble swallowing).
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Hematemesis (vomiting blood).
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Unintentional weight loss.
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Frequent and long-standing heartburn (pain in the chest).
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Bad breath.
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Blood in stool.
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Vomiting.
What Are the Foods to Be Avoided in Barrett’s Esophagus?
Avoiding the following food help to improve the symptoms of Barrett’s esophagus:
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Chocolate.
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Toffee.
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Fried food.
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Peppermint.
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Spicy foods.
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Carbonated beverages.
These foods increase the level of acid in the stomach. Hence it is better to avoid them.
Is Barrett’s Esophagus a Cancerous Condition?
The metastatic changes occurring in the esophagus may sometimes turn dysplastic. In dysplasia, the cells turn abnormal, which is irreversible and likely leads to cancer. Barrett’s esophagus is a precancerous condition and most likely causes esophageal adenocarcinoma (a type of cancer occurring in glands lining the organs).
What Is the Diagnosis of Barrett’s Esophagus?
Barrett’s esophagus is usually diagnosed using an endoscope. The endoscope is a thin, flexible medical device with a light and camera attached to its end that helps view inside the body. The esophageal usually appears pale, but in Barrett’s esophagus, they appear red.
What Is the Treatment for Barrett’s Esophagus?
The treatment of Barrett’s esophagus mainly depends on the presence of symptoms. Medications to decrease stomach acid and lifestyle modifications help to improve the condition. The physician may periodically monitor for any cancerous changes in the esophagus. If esophageal cancer is detected, surgery may be recommended to remove the affected parts of the esophageal lining.
Conclusion:
Barrett’s esophagus is treated by maintaining a healthy esophagus and managing the symptoms of GERD. In addition, avoiding food containing acidic content helps to decrease the risk of this disease. Also, maintaining a healthy weight and diet is found beneficial.
