Loading…
Challenges in Diagnosis and Treatment of Systemic Amyloidosis: 10 Years of Experience in a Public Brazilian University Center
Systemic Amyloidosis (SA) results from tissue deposition of insoluble protein fibrils leading to organ dysfunction. Considering the scarcity of data from Latin America, a retrospective study was conducted by reviewing medical records of patients with biopsy proven SA diagnosed from 2009 to 2018 at a...
Saved in:
| Published in: | Blood 2020-11, Vol.136 (Supplement 1), p.6-8 |
|---|---|
| Main Authors: | , , , , , , , , , , , , |
| Format: | Article |
| Language: | English |
| Citations: | Items that cite this one |
| Online Access: | Get full text |
| Tags: |
Add Tag
No Tags, Be the first to tag this record!
|
| Summary: | Systemic Amyloidosis (SA) results from tissue deposition of insoluble protein fibrils leading to organ dysfunction. Considering the scarcity of data from Latin America, a retrospective study was conducted by reviewing medical records of patients with biopsy proven SA diagnosed from 2009 to 2018 at a public tertiary center to assess clinical, laboratory and therapeutic features.
Confirmed SA subtype was established if causative protein was identified on tissue biopsies by immunohistochemistry (IHC), indirect immunofluorescence (IIF), mass spectrometry (MS) or in the presence of pathogenic gene mutation related to SA. Probable cases were classified as light chain SA (AL) if evidence of monoclonal gammopathy (MG), transthyretin SA (ATTR) if moderate/strong cardiac uptake in 99mTc-pyrophosphate scintigraphy (99mTc-PYP), classical neurological symptoms with familial history or previous liver transplant from a donor with hereditary ATTR (hATTR), and secondary SA (AA) in the context of underlying chronic inflammatory disease. Inconclusive cases had ≥2 concomitant features suggestive of different subtypes.
Primary endpoint was overall survival (OS).
From 198 cases revised, 110 met the eligibility criteria. Median age was 60 years, 56% were male.
Before diagnosis 53% were seen by ≥3 physicians: 65% general practitioners, 45% nephrologists, 42% cardiologists. Median time from onset of symptoms to diagnosis was 11.3 months. In 79% of patients ECOG was ≤2.
Clinical presentations were: 54% renal disorders, 43% heart disease, 36% consumptive syndrome, 26% gastrointestinal symptoms, 25% neuropathy, 19% fatigue, 12% skin lesions, 9% hepatic disorders.
The mean number of biopsies performed per patient was 2.3 and 60% had a method to subtype amyloid on biopsy: 67% IIF, 36% IHC and MS in 1 case.
Mean number of affected organs was 2.6 (19% 1 organ, 38% 2 and 43% ≥ 3). Main organs were: 75% heart, 55% kidney, 43% soft tissue, 37% peripheral nervous system. Dialysis patients were 12%.
Positive familial history was seen in 7% and 17% were tested for genetic mutations: 63% for transthyretin, 21% fibrinogen, 5% lysozyme, 16% MEFV gene.
MG screening was assessed in 97% of patients, amyloid protein A in 4 and 99m Tc-PYP performed in 11.
SA subtypes were confirmed in 32% of patients, probable in 59% and inconclusive in 9%. Frequency of subtypes were 68% AL, 12% ATTR, 6% AA, 4% fibrinogen amyloidosis (AFib), 1% lysozyme amyloidosis (ALys).
Most of AL were λ (75%) and 34% had coexistin |
|---|---|
| ISSN: | 0006-4971 1528-0020 |
| DOI: | 10.1182/blood-2020-136456 |