What are Pathognomonic Symptoms?

What are pathognomonic symptoms? What is special about them, that these are given title of pathognomonic symptoms? They are given this name because this name define their complete story of, why they are called with this name?

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They are given this name because of their special center theme. Pathognomonic symptoms are symptoms which arise in human body out of disease and reflect disease's pathological arena. 

• These are symptoms which reflect pathology of disease occurring inside human body and also tell at which stage disease is progressing pathology wise. 
• But, what is this pathology and pathological manifestation mean? Pathology means study of disease and pathological manifestations means manifestations of disease occurring in structural format of human body.

• Pathological symptoms can be functional and they can be on structural plane too. That depends on at what stage disease is. Initially pathognomonic or also called pathological symptoms occur at functional plane; but as the disease progress they progress towards structural changes. So, pathognomonic symptoms are those symptoms or changes which disease process produce inside human body.

Surely, you would also like to know examples of pathognomonic symptoms. Examples are those symptoms with which you identify disease; for example, if a person coughs constantly repeatedly from few days, then here, "cough" is pathognomonic symptoms. If anybody says that some structural changes are found in the ultrasound of their kidneys; here, these "Structural changes" occurring in kidney are pathognomonic symptoms.

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