Paraproteinemic keratopathy as the presenting sign of hematologic malignancy

Prevalence of corneal findings and their interrelation with hematological findings in monoclonal gammopathy

PURPOSE

To determine prevalence of paraproteinemic keratopathy (PPK) among patients with monoclonal gammopathy (MG). To evaluate interrelation between corneal and hematological parameters in patients with PPK.

METHODS

Fifty-one patients with monoclonal gammopathy of undetermined significance (n = 19), smoldering multiple myeloma (n = 5) or multiple myeloma (n = 27) were prospectively included in this study. Best-corrected visual acuity, slit-lamp biomicroscopy, Scheimpflug tomography, in-vivo confocal laser scanning microscopy, optical coherence tomography and complete hematological workup were assessed.

RESULTS

We identified n = 19 patients with bilateral corneal opacities compatible with PPK. PPK was newly diagnosed in 13 (29%) of 45 patients with a primary hematological diagnosis and in n = 6 patients without previous hematological diagnosis. The most common form was a discreet stromal flake-like PPK (n = 14 of 19). The median level of M-protein (p = 0.59), IgA (p = 0.53), IgG (p = 0.79) and IgM (p = 0.59) did not differ significantly between the patients with and without PPK. The median level of the FLC κ in serum of patients with kappa-restricted plasma cell dyscrasia was 209 mg/l in patients with PPK compared to 38.1 mg/l in patients without PPK (p = 0.18). Median level of FLC lambda in serum of patients with lambda-restricted plasma cell dyscrasia was lower in patients with PPK compared to patients without PPK (p = 0.02).

CONCLUSION

The PPK was mostly discreet, but its prevalence (29%) was higher than expected. Median level of the monoclonal paraprotein was not significantly higher in patients with PPK compared to patients without PPK. Our results suggest a lack of correlation between morphology and severity of the ocular findings and severity of the monoclonal gammopathy.

TRIAL REGISTRATION

German Clinical Trial Register: DRKS00023893.

Diagnosing Paraproteinemic Keratopathy: A Case Report

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 (TGFBI) and collagen type XVII alpha 1 gene (COL17A1). 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.

Identification of A Novel TGFBI Gene Mutation (p.Serine524Cystine) Associated with Late Onset Recurrent Epithelial Erosions and Bowman Layer Opacities

BACKGROUND

Most transforming growth factor beta-induced (TGFBI) corneal dystrophies are associated with a characteristic phenotype, clinical course, and a conserved mutation in the TGFBI gene. However, we report a novel TGFBI missense mutation associated with a late-onset, variant Bowman layer dystrophy.

METHODS

Participants underwent slit-lamp examination and multimodal imaging. Polymerase chain reaction amplification and Sanger sequencing were performed on saliva-derived genomic DNA to screen TGFBI exons 4 and 12 as well as COL17A1 exon 46. PolyPhen-2 and SIFT were used to predict the functional impact of any identified variants.

RESULTS

A 56-year-old Thai woman reported a four-year history of decreased vision and intermittent eye irritation, suggestive of recurrent epithelial erosions, in both eyes. Slit-lamp exam revealed bilateral, irregular, limbal-sparing Bowman layer opacities, which were also noted on anterior segment optical coherence tomography. Phototherapeutic keratectomy was performed in the right eye, improving the best-corrected visual acuity from 20/50 to 20/30. Sequencing of the TGFBI gene revealed a novel heterozygous, missense mutation in exon 12 (c.1571 C > G; p.Ser524Cys), which was present in an affected son and absent in an unaffected son, and was predicted to be damaging by PolyPhen-2 and SIFT. The patient was diagnosed with a variant Bowman layer dystrophy given the late onset of an atypical phenotype and the identification of a novel TGFBI mutation.

CONCLUSIONS

A novel TGFBI missense mutation is associated with a late-onset Bowman layer dystrophy. Given the atypical clinical appearance and course, molecular genetic analysis was utilized to establish a definitive diagnosis.

Multimodal Imaging Report of Crystalline Keratopathy in Relapsing Polychondritis

PURPOSE

To describe a case of bilateral multifocal stromal crystalline keratopathy in the setting of relapsing polychondritis (RP).

METHODS

Case report.

RESULTS

We describe a 31-year-old woman who presented with ocular inflammation, bilateral auricular chondritis, and nasal chondritis, meeting the clinical criteria of RP. We illustrate her auricular cartilaginous abnormalities, saddle nose deformity, scleritis, and discrete mid-stromal opacities in both corneas that extend through the central cornea. Uniquely, her opacities feature a marked crystalline component as demonstrated on photography, anterior segment optical coherence tomography, and confocal microscopy.

CONCLUSION

A central keratopathy is not typically reported in patients with RP. In this case report, we describe a unique diffuse bilateral nummular mid-stromal crystalline keratitis that extends into the central cornea and further define it using multimodal imaging.

Characterization of corneal deposition keratopathy in the setting of blood cell dyscrasia and a minimally invasive technique to clear the cornea in a single case

Purpose

To report 3 cases of corneal protein deposition occurring in association with systemic disease, with one case demonstrating a novel technique for clearing corneal deposits.

Observations

Three patients presented with corneal deposits associated with systemic disease. Corneal involvement was noted prior to diagnosis of systemic disease in two patients, leading to subsequent diagnosis of multiple myeloma or monoclonal gammopathy of undetermined significance. OCT revealed protein deposition at various corneal levels, including at different stromal depths in the two cases of multiple myeloma. A novel technique of posterior endothelial scraping was performed in one case with deep stromal deposits, leading to significant corneal clearing.

Conclusions and Importance

This case series demonstrates that recognition of corneal deposits may precede the diagnosis of systemic disease. It incorporates the use of anterior segment OCT to characterize corneal deposits, and demonstrates a novel surgical technique for clearing certain types corneal deposits.