<unk>  is caused by intrinsic and extrinsic changes in the gastrointestinal system, including uptake of antibodies and bacterial infection. Less commonly, it can be caused by cancer, a life-threatening cause requiring prompt diagnosis and treatment.
Achlorhydria causes
Milk-alkali syndrome causes
Acute diarrhea causes
Headaches in children causes
Gastritis causes
Polydipsia causes
Stomatitis causes
Heartburn causes