Amyloidosis

Amyloidosis is a rare and serious disease that could be fatal that is caused by accumulation of proteins in the form of abnormal, insoluble fibres, known as amyloid fibrils, within the tissues of the body. 
Amyloid deposits can be confined to only one part of the body or a single organ system in 'local amyloidosis' or they can be widely distributed in organs and tissues throughout the body in 'systemic amyloidosis'. The symptoms of amyloidosis are accordingly highly variable and confirmation of the presence of amyloid in the tissues can be challenging, so that diagnosis is often delayed.
There are many different types of amyloidosis, each caused by formation of amyloid fibrils from different soluble precursor proteins in different patients. About 30 different proteins are known to form amyloid fibrils in humans and amyloidosis is named and classified according to the identity of the respective fibril protein. 
Though this disease being rare, many famous people have died from this disease such as: Martin McGuinness, David Lange, Robert Jordan and Robert P. Casey.