**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.**
Santiago Martinez-Sosa, Mayo Clinic Hospital, Rochester, Minnesota

**Main Body of the Abstract**
Background: Rarely, patients may exhibit two types of amyloidosis concurrently. The co-existence of three types of amyloidosis has not been previously reported.
Case report: A 56-year-old male with no medical comorbidities presented with a 1-year history of progressive and asymmetric bilateral shoulder weakness. Examination was notable for moderate-to-severe asymmetric weakness and atrophy of shoulder girdle muscles, right worse than left. EMG demonstrated a proximal myopathy.  CK was elevated at 439 U/L (N<308). Monoclonal gammopathy screen showed a small IgA lambda monoclonal gammopathy with elevated lambda free light chain and a kappa/lambda ratio of 0.0787. A right triceps muscle biopsy demonstrated interstitial amyloid deposits. Mass-spectrometry–based proteomics identified an AL lambda peptide profile. Fat aspirate and bone marrow biopsy were also positive for amyloid deposits. Fat aspirate mass-spectrometry identified AL lambda and AA (serum amyloid A) peptide profiles. A subsequent abdominal fat pad biopsy demonstrated both AL and AA amyloid deposits. Bone marrow biopsy showed 5% lambda light chain restricted plasma cells, and AL and wild-type ATTR amyloid deposits. TTR gene sequencing was negative. Major organ involvement was ruled out by laboratory tests, as well as PYP-SPECT-CT.
Conclusions: Our case represents the first description of triple amyloidosis (AL, AA and wtATTR) in a single individual. It is noteworthy that only AL lambda was identified in his single symptomatic organ (skeletal muscle) amyloid deposits. Given overlapping clinical syndromes and type-specific therapy, the identification of one amyloid type should not preclude additional workup aimed at identifying other amyloid types occurring in the same patient.



**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.**
Santiago Martinez-Sosa, Mayo Clinic Hospital, Rochester, Minnesota

**Main Body of the Abstract**
**Background**: Rarely, patients may exhibit two types of amyloidosis concurrently. The co-existence of three types of amyloidosis has not been previously reported.
**Case report:** A 56-year-old male with no medical comorbidities presented with a 1-year history of progressive and asymmetric bilateral shoulder weakness. Examination was notable for moderate-to-severe asymmetric weakness and atrophy of shoulder girdle muscles, right worse than left. EMG demonstrated a proximal myopathy.  CK was elevated at 439 U/L (N<308). Monoclonal gammopathy screen showed a small IgA lambda monoclonal gammopathy with elevated lambda free light chain and a kappa/lambda ratio of 0.0787. A right triceps muscle biopsy demonstrated interstitial amyloid deposits. Mass-spectrometry–based proteomics identified an AL lambda peptide profile. Fat aspirate and bone marrow biopsy were also positive for amyloid deposits. Fat aspirate mass-spectrometry identified AL lambda and AA (serum amyloid A) peptide profiles. A subsequent abdominal fat pad biopsy demonstrated both AL and AA amyloid deposits. Bone marrow biopsy showed 5% lambda light chain restricted plasma cells, and AL and wild-type ATTR amyloid deposits. TTR gene sequencing was negative. Major organ involvement was ruled out by laboratory tests, as well as PYP-SPECT-CT.
**Conclusions**: Our case represents the first description of triple amyloidosis (AL, AA and wtATTR) in a single individual. It is noteworthy that only AL lambda was identified in his single symptomatic organ (skeletal muscle) amyloid deposits. Given overlapping clinical syndromes and type-specific therapy, the identification of one amyloid type should not preclude additional workup aimed at identifying other amyloid types occurring in the same patient.



Triple amyloidosis: AL, AA, and wild-type ATTR in a single patient with amyloid myopathy PC17 (#240)

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.