Early onset coats’ disease initially treated as unilateral ROP at 39 weeks postmenstrual age: a case report

BACKGROUND This is the youngest case of Coats' disease, in terms of postmenstrual age (PMA), to be reported in the literature. This case highlights the remarkable variations in the clinical manifestations and the very early onset of Coats' disease. This case is unusual in both the age of onset and atypical clinical features, which resemble retinopathy of prematurity (ROP). CASE PRESENTATION We report a case of a preterm boy born at 31 5/7 weeks gestational age who presented with atypical Coats' disease and was initially diagnosed as having ROP of only one eye at 39 weeks PMA. After initial laser treatment, severe exudative retinal detachment (ERD) occurred after initial laser treatment for ROP. Fundus fluorescein angiography (FFA) showed telangiectasia and anastomosis of peripheral retinal vessels and nonperfusion areas, and the diagnosis of Coats' disease was thus established. A series of intravitreal injections of ranibizumab (IVR) and laser ablations were performed to resolve the exudation and to ablate the abnormal vessels. At the last visit, the retinopathy was under control, and useful vision was preserved. CONCLUSIONS Coats' disease resembling stage 3 ROP can be detected before the expected date of childbirth. Therefore, asymmetric ROP should be differentiated from Coats' disease.