Correlation between visual function and clinical/subclinical disease activity parameters in Vogt-Koyanagi-Harada disease (VKHD).

Abstract

Purpose : To evaluate the impact of subclinical inflammation over visual function in VKHD patients.

Methods : Patients diagnosed with VKHD in the acute phase were prospectively included, with a minimum 24-mo follow-up. They were initially treated with methylprednisolone pulsetherapy followed by oral prednisone (1mg/kg/d) only (CS group) or by oral prednisone associated with immunosuppressant (IS group). Oral prednisone had a slow tapering (12-15 mo). Patients were evaluated every 3 mo clinically, with indocyanine green (ICGA) and fluorescein (FA) angiographies, and, with enhanced depth optical coherence tomography (EDI-OCT)] (Spectralis HRA+OCT, Heidelberg). Full-field electroretinogram (ffERG) was carried out at inclusion and every 6 mo. Subclinical signs were defined as: optic disc or perivascular leakage (FA); dark dots (DD)(ICGA) and/or choroidal thickness increase (CTI) on EDI-OCT. Clinical signs were defined as: cells in anterior chamber; choroidal neovascularization and/or macular edema. Immunosuppressants were associated to CS on the presence of clinical signs or clinical intolerance to prednisone. Descriptive statistics, Fisher's exact test and generalized estimating equations were used to analyze data. This study was approved by the Ethics Committee and follows the Helsinki declaration.

Results : Eight patients (6W) were included, with median age at diagnosis of 27 y and median time from symptoms till treatment of 15 d. During follow-up, 7 eyes (44%) had clinical signs; all eyes persisted with DD, 6 (37%) had CTI and 2 eyes (12%) had FA signs. CS (n=4) and IS (n=4) groups did not differ demographically and clinically. During the follow-up, after an initial recovery of ffERG parameters, they tend to decrease in 6 eyes (3 p) or to ascend or stabilize in 10 eyes (5 p). Among patients with ascending or stable ffERG, 80% belonged to IS group and none to CS group (p=0.007, Fisher's exact test). Furthermore, DD score decreased during follow-up in IS group only (p=0.001).

Conclusions : In this limited sample of patients, an indirect correlation between subclinical inflammation (represented by DD) and worse visual function could be observed. DD persisted in all patients after 24-mo follow-up, however they decreased in IS group, which had a better visual function performance during this follow-up.

This is an abstract that was submitted for the 2017 ARVO Annual Meeting, held in Baltimore, MD, May 7-11, 2017.

 

Figure 1 - Characterization of patients with VKHD during 24-month follow-up.