Our internal body system is constantly at work and innumerable activities such as cell division, repairing damage cells, building new cells, exchange and breakdown of energy as well as transformation of tissues and cells in various types owing to different chemical reactions are going on in a non ceasing manner. Some such changes are beneficial for our body whereas some might create problems. Metaplasia too is a natural process which can be beneficial or problematic depending upon whether it is normal or abnormal.
Transition of one type of tissue into another type is called as Metaplasia. The term Metaplasia means ‘change in form’. In case of normal Metaplasia cartilage becomes hard to get transformed into You do not have access to view this node (Ossification) which is beneficial activity. During this process exchange of one special differentiated type of cell with another matured differentiated type of cells occurs.
Abnormal Metaplasia is a very serious condition and is an harbinger of some grave medical problem. This type of Metaplasia is caused as a response to stress or even a stimulus that motivates the replacement of delicate weak cells by the hardier cells. For example, in cervical Metaplasia, the epithelial lining of organs internally placed gets changed from columnar to squamous as a response to stress. The process is usually reversible, mostly when the reason for metaplasia is removed or treated.
More often, Metaplasia is caused when the cells in the body placed in a particular location are not strong enough to take care of the stress or even externals stimuli to which these cells are exposed. Hence these cells get replaced by another set of cells which are better equipped to withstand the changes in the new environment. Although the new cells are of the same age as the replaced cells, they many times are not suitable for that particular location in the body and cannot perform the normal functions of that area well. Some of the common causes of this disorder are smoke irritation, vitamin A deficiency, kidney stones or worm infestations and acid reflux. Many times, the Metaplasias are considered to be precancerous (Barrett’s esophagus), and if the cause is removed, the tissues have been found to return back to normal condition. When Metaplasis is not treated immediately, it can turn to dysplasia or can become cancerous.
The swallowing tube or normal esophagus is mostly lined by squamous epithelium which is a pinkish-white tissue. Many people are also known to have columnar epithelium or red stomach tissue located at the bottom of the esophagus. When the normal squamous epithelium in the esophagus is replaced by the abnormal columnar epithelium, the process is called specialized intestinal metaplasia. This type of plasia is red in color like the normal stomach tissue but looks different when observed under the microscope. For making a diagnosis, tissue piece is taken from esophagus for biopsy. The lining of Barrett’s always starts from the bottom of the esophagus, a place where it joins the stomach and then goes up further towards the mouth. Barrett’s lining are of various lengths and can be short, 1.3 inches in length or long with 3 cm or more in length.