AUTOIMMUNE RETINOPATHY IN A PATIENT WITH A MISSENSE MUTATION IN PITPNM3
To describe a patient with a PITPNM3 missense mutation who developed late-onset autoimmune retinopathy.Methods:
An 85-year-old man presented with decreased vision, nyctalopia, and photoaversion after an uncomplicated cataract surgery. Multimodal retinal imaging revealed a scalloped pattern of atrophy and a ring of hyperautofluorescence in the perifoveal area on fundus autofluorescence. Spectral domain optical coherence tomography demonstrated loss of the ellipsoid band, along with outer retinal atrophy, sparing the fovea in both eyes. Full field electroretinogram revealed extinguished rod response and severely attenuated cone response. Antiretinal antibodies to 20-kDa and 125-kDa proteins were detected. Whole-exome sequencing revealed a heterozygous variant, c.2579T>C, p.(Ile860Thr) in PITPNM3, predicted to be severely damaging and deleterious to the protein structure and function. Over the course of 3 months, the patient experienced a rapid progression. Neoplastic workup was negative and he was started on immunosuppressive therapy for a presumed diagnosis of nonparaneoplastic autoimmune retinopathy.Conclusion:
To the authors' knowledge, this is the first report of autoimmune retinopathy in a patient with PITPNM3 mutation. PITPNM3 has been previously shown to affect regulatory T cell function.