1 Examples of viral infections include, mumps or hepatitis B. 2  Some autoimmune conditions-such as lupus, or Sjogren's syndrome. 3  Injury to the pancreas. 4  Idiopathic-about 15% of all cases of acute pancreatitis are termed idiopathic pancreatitis.
For instance, in America, these kinds of drums are referred to as the doumbek. They are widely used in E. Europe, N. Africa and a larger part of Asia. Good examples of these kinds of drums include the Bendir, Riq, Tamburine, Irish bodhran etc. These drums are mostly made of wood which forms almost a perfect circle.
All instruments such as drums and bells fall into this category. The formal classifications of most percussion instruments are either idiophones (instruments that vibrate when struck, shook, plucked, or scraped) or membranophones (instruments that have a stretched membrane that vibrates when struck, shook, or rubbed).