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Ocular Adnexal Amyloidosis: A Mass Spectrometric Analysis
Alexander D Blandford1, Sari Yordi1, Saloni Kapoor1
1Cole Eye Institute, Cleveland Clinic, Cleveland, Ohio, USA.
American Journal of Ophthalmology
|June 12, 2018
Summary
Mass spectrometry accurately identifies AL amyloid protein in ocular adnexal amyloidosis (OAA), unlike immunohistochemistry. This aids in diagnosing systemic involvement and guiding treatment for OAA patients.
Area of Science:
- Ophthalmology
- Pathology
- Medical Diagnostics
Background:
- Ocular adnexal amyloidosis (OAA) can indicate systemic disease.
- Accurate amyloid fibril identification is crucial for systemic evaluation and treatment.
- This study aimed to subtype OAA and correlate findings with ocular and systemic involvement.
Observation:
- A retrospective case series reviewed OAA patients from 1995-2017.
- Immunohistochemistry identified AL amyloid in 67% of cases, while mass spectrometry identified it in 100%.
- AL lambda was found in 50%, kappa in 30%, and both in 20% of samples.
Findings:
- Mass spectrometry is superior to immunohistochemistry for diagnosing OAA subtypes.
- AL amyloidosis is the most common OAA subtype identified by mass spectrometry.
- Systemic involvement was noted in 3 cases, including eyelid and uveal tissues.
Implications:
- OAA diagnosis requires precise amyloid typing, preferably via mass spectrometry.
- Immunohistochemistry may be insufficient for characterizing OAA amyloid deposits.
- Further evaluation for systemic disease or lymphoproliferative disorders is recommended for OAA patients.
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