Conjunctival lymphangiectasia as a biomarker of severe systemic disease in Ser77Tyr hereditary transthyretin amyloidosis.

AIMS: To investigate the relationship between the ophthalmic and systemic phenotypes in patients with hereditary transthyretin amyloidosis with the S77Y mutation (ATTRS77Y).

METHODS: In this cross-sectional study, patients with genetically confirmed ATTRS77Y amyloidosis were enrolled. All patients underwent complete neurological examination, including staging with the Neuropathy Impairment Score (NIS), Polyneuropathy Disability (PND) score; complete cardiological evaluation, including echocardiography, cardiac MRI and/or cardiac scintigraphy and complete ophthalmic evaluation, including slit lamp examination and fundus examination. Ocular ancillary tests (fluorescein and indocyanine green angiography, and anterior segment optical coherence tomography) were performed in cases with abnormal findings. The Kruskal-Wallis test was used for quantitative outcomes and Fisher's exact test for qualitative outcomes. Statistical significance was indicated by p<0.05 (two tailed).

RESULTS: The study sample was composed of 24 ATTRS77Y patients. The mean patient age was 58.4±12.4 years. None of the patients presented with amyloid deposits in the anterior chamber, secondary glaucoma or vitreous amyloidosis. Retinal angiopathy was observed in four patients, complicated with retinal ischaemia in one patient. Conjunctival lymphangiectasia (CL) was detected in 13 patients (54%), associated with perilymphatic amyloid deposits. The presence of CL was statistically associated with more severe neurological disease (NIS=43.3±31.9 vs 18.9±20.4; PND=2.6±1.0 vs 1.4±0.7 in patients with and without CL, respectively; both p<0.05) and amyloid cardiomyopathy (p=0.002).

CONCLUSION: In ATTRS77Y patients, CL is common and could serve as a potential biomarker for severe systemic disease. There were neither anterior chamber deposits, secondary glaucoma nor vitreous deposits in ATTRS77Y patients.