A rare clinical case of systemic AA amyloidosis with cardiac involvement complicating ankylosing spondylitis: a case report

Ankylosing spondylitis (AS) is a type of chronic inflammation that is most prevalent in young adults and is characterized by an inflammatory enthesiopathy that gradually develops toward ossification and ankylosis. If inflammation is left unchecked, it can potentially lead to complications such as secondary amyloidosis, also known as AA amyloidosis, involving the deposition of amyloid serum A protein. Our case presents with a thyroid localization of AA amyloidosis which is secondary to this AS. Such a case has been described in only four cases in the literature. Cardiac localization of AA amyloidosis has been exceptionally described in the literature.