Diagnosing Paraproteinemic Keratopathy: A Case Report

Abstract

A 65-year-old man presented with bilateral, painless, progressive blurring of vision over 9 years. Slit-lamp examination revealed bilateral subepithelial corneal opacities in clusters located at the mid-periphery. Anterior segment optical coherence tomography, in vivo confocal microscopy (IVCM), serum protein electrophoresis, and molecular genetic testing were performed to evaluate the cause of corneal opacities. Anterior segment optical coherence tomography revealed a band-like, hyperreflective lesion in the Bowman layer and anterior stroma of both corneas. IVCM revealed hyperreflective deposits in the epithelium, anterior stroma, and endothelium. Serum protein electrophoresis identified the presence of paraproteins (immunoglobulin kappa), and molecular genetic testing revealed absence of mutations in the transforming growth factor beta-induced gene (<i>TGFBI</i>) and collagen type XVII alpha 1 gene (<i>COL17A1</i>). The ocular diagnosis of paraproteinemic keratopathy eventually led to a systemic diagnosis of monoclonal gammopathy of undetermined significance by our hematologist/oncologist. Paraproteinemic keratopathy is a rare differential diagnosis in patients with bilateral corneal opacities and therefore may be misdiagnosed as corneal dystrophy or neglected as scars. In patients with bilateral corneal opacities of unknown cause, serological examination, adjunct anterior segment imaging, and molecular genetic testing play a role in establishing the diagnosis.

Monoclonal Gammopathies of Clinical Significance: A Critical Appraisal

“…However, when it is not feasible due to the location of the corneal pathology, aqueous sampling may be an alternative approach for diagnostic purposes. The term MGOS was proposed for patients diagnosed with MGUS, in which the only significant clinical finding is ocular manifestation [ 54 , 76 , 77 , 78 ]. A regular, yearly ophthalmic checkup of these patients to improve their quality of life has been suggested.…”

Corneal nerve changes in herpes zoster ophthalmicus: a prospective longitudinal in vivo confocal microscopy study

“…In recent years, the use of in vivo confocal microscopy (IVCM) has gained a bigger role in the diagnosis and monitoring of corneal diseases [6][7][8], but the number of IVCM studies in this relatively common condition of HZO were limited to case reports or small series [9][10][11][12]. Significant alterations of corneal nerves were detected in a patient at 2 years after onset of HZO, including scarce non-branching subbasal nerves and even absence of subbasal nerves in the affected eye [9].…”