**Author Listing - Lead/ Submitting Author (we will be communicating with this individual): Name, Institution, City and State where the work was done. Co-authors will be added in a separate section.**
Larissa Ventura Ribeiro Bruscky, Instituto Dante Pazzanese de Cardiologia, São Paulo-SP, Brazil.

**Main Body of the Abstract**
Introduction: Localized amyloidosis refers to the deposition of amyloid fibrils in specific organs. Airways, bladder, eyes and digestive tract are the most common sites. When amyloid deposits are found on biopsy, it is imperative to look for involvement in other sites. We describe 3 cases of amyloidosis that were initially seen as localized and, after further investigation, two of them were systemic.
Methods: Observational case series study
Casuistry: Three patients, all male, presented with localized amyloid fibril deposition. Clinical characteristics are listed in Table 1. P1: had episodes of hoarseness associated with chest pain, fever and diarrhea. A laryngeal biopsy showed amyloid deposits in the trachea. P2 and P3 had tumor lesions on the ocular conjunctiva. Mass spectrometry: P1 and P3 had lambda-type light chain amyloid deposit and P2 macular amyloid deposit. Cardiac magnetic resonance results: P1: significant hypokinesia and late enhancement in the inferolateral wall; P2: symmetrical left ventricular hypertrophy (probably related to aortic stenosis); P3: septal thickness of 13mm and a slight increase in the T1 map (1162).
Comments: Only in P2, who had macular amyloidosis, a protein located exclusively in the skin, it was easy to exclude systemic involvement. In P1 systemic involvement was considered, and the patient received specific therapy for light chain amyloidosis. In P3, the cardiac resonance findings were not sufficient for the hematologist to recommend treatment.
Conclusions: despite laborious diagnostic workout, it is challenge to differentiate between localized and systemic amyloidosis.



Challenge to differentiate between localized and systemic amyloidosis: case series report PC6 (#474)

We invite you to attend the XIX International Symposium on Amyloidosis to be held in Rochester, MN.

This symposium is organized as a hybrid meeting (with the focus on in-person) held from Sunday, May 26 through Thursday, May 30, 2024.

Together with the ISA Board and members of Mayo Clinic, a very attractive scientific hybrid program is being planned. The program will cover a variety of types of systemic amyloidosis: ATTR (hereditary and wild-type), AL (light-chain), AA and less frequent forms. There will be key lectures, specific symposia including those company sponsored, oral presentations and poster sessions of accepted abstracts.

COURSE DESCRIPTION
This program will provide a comprehensive review of state-of-the-art education in systemic amyloidosis: basic science, pathophysiology, diagnosis, current and emerging treatments. Scientific presentations will include competitive oral and poster abstracts. The rapid evolution of scientific discovery and expanding treatment options has created tremendous interest in the field and this meeting will fill and important gap in educating scientists and clinicians.