What does it mean by gluten sensitivity?

Among gluten-related disorders, gluten sensitivity is an emerging entity that is characterized by a wide array of manifestations. In particular, patients complain of IBS (Irritable bowel syndrome)-like symptoms and extraintestinal manifestations that occur shortly after the ingestion of gluten. Symptoms improve or disappear when gluten is withdrawn from the diet, and recur if gluten is reintroduced.

Gluten is found in grains such as wheat, barley, rye, and a cross between wheat and rye called triticale. It is a complex protein formed of two protein structures: gliadin and glutenin, connected by disulfide bridge. Gluten is the magical protein responsible for the capability for bread dough to rise and contain carbon dioxide. Gluten components create a 3D network when flours are mixed with water, giving dough elasticity and viscosity.

The clinical presentation of gluten sensitivity is a combination of IBS-like symptoms, including abdominal pain, bloating, bowel habit abnormalities (either diarrhea or constipation), and systemic manifestations such as ‘foggy mind’, headache, fatigue, joint and muscle pain, leg or arm numbness, dermatitis (eczema or skin rash), depression and anemia.

People with gluten sensitivity have problems with gluten. It is different from celiac disease, an immune disease in which people can't eat gluten because it will damage their small intestine.

Some of the symptoms of gluten sensitivity are similar to celiac disease. They include tiredness and stomachaches. It can cause other symptoms too, including muscle cramps and leg numbness.
What does it mean by gluten sensitivity?