Amyloid tells something of the form in which proteins can
be deposited in tissue and organs. Different proteins can be deposited in
various sites of the human body in the form of amyloid. When these deposits in a
piece of tissue (a so-called biopsy) are viewed under a microscope in normal
light, it looks amorphous material. However, if the same deposits are viewed
under an electron microscope with higher magnification, it has been built up by
enormous amounts of small non-branching fibrils, the amyloid fibrils. When a
biopsy has been stained with Congo red dye, the amorphous deposits become red. A
characteristic feature of amyloid is that this red deposits become green when
viewed in polarized light.
As stated above, different proteins can be deposited in various sites in tissue in the form of amyloid. These deposits can remain strictly localized (such as in the pancreas, the brain, the trachea) or systemic in the whole body. Localized forms of amyloid are relatively frequent (such as in the brain in Alzheimer's disease and in the pancreas in maturity onset diabetes mellitus) and - despite the fact that these forms are also called amyloid - these forms are completely different from each other and from the systemic forms of amyloid.
A second way to distinguish different forms of amyloid is whether they are inherited or not (inherited versus acquired). However, nowadays the best way to distinguish the different forms of amyloid is by a chemical characterization. This (immuno-)chemical typing of amyloid is generally accepted and should be done in all patients with amyloid. A piece of tissue, a biopsy, may reveal the type of amyloid involved. It is important that it should be clear in each patient whether deposition of amyloid is limited (localized) or throughout the whole body (systemic). In case of systemic amyloidosis, because of therapeutic differences it should become completely clear which of the three main types of systemic amyloidosis is involved (or if not one of these three, which other rare type of amyloidosis may be present). The three most important types of systemic amyloidosis are AL, AA, and ATTR amyloidosis.
A film, Amyloidosis Awareness, encourages understanding of the main types of amyloidosis, methods of diagnosis, treatment options, and resources for more information. While the film is primarily targeted to doctors, medical students and other health care providers, it will have a broad appeal such that the patient community can also benefit from its message. Watch the full screen version of the movie or a smaller version of the movie with subtitles via Youtube.