Predominant exudative retinopathy in incontinentia pigmenti and clinical course after peripheral laser photocoagulation

Abstract

Dear Editor, Incontinentia pigmenti (IP) (Bloch-Sulzberger syndrome) is an X-linked condition with dermatological, dental, neurological and ocular abnormalities. Ocular abnormalities occur in 25–77% cases of IP.[1] The characteristic manifestation is a proliferative retinopathy which includes peripheral retinal vascular nonperfusion, preretinal neovascularization, preretinal or vitreous hemorrhage and infantile tractional retinal detachment.[2] In contrast, an early presentation of IP as predominant exudative retinopathy is not commonly reported.[3] We report a case of IP with predominant exudative retinopathy and successful resolution after laser photocoagulation. A 50-day-old female infant was referred for ophthalmology examination from pediatric neurology. The infant was born with an uneventful normal delivery at term and a birth weight of 3000 g. The infant had a vesicular rash on extremities at birth and seizures since second day of life. The infant was diagnosed as IP based on the typical skin lesions [Fig. 1a], magnetic resonance imaging (MRI) findings and pathological findings on skin biopsy.Figure 1: (a) Skin lesions on the trunk and the arm; (b) fundus right eye shows abnormally dilated and tortuous posterior pole vessels, exudative retinal detachment and multiple hemorrhages; (c) right eye, 1 month after laser with residual lipid exudates and nasal falciform fold; (d) right eye, 6 months after laser shows nasal falciform fold and submacular scar (arrow)On fundus examination of right eye, there were dilated and tortuous vessels with exudative retinal detachment at the posterior pole [Fig. 1b]. On indirect ophthalmoscopy with scleral indentation, there was 360° peripheral avascular retina with multiple preretinal hemorrhages. The left eye revealed dilation of posterior pole vessels, minimal exudation in posterior pole, few preretinal hemorrhages and peripheral avascular retina. In view of severe vascular abnormalities, the infant underwent bilateral laser photocoagulation of the entire peripheral avascular retina with diode laser (IRIS Medical Oculight SL, 810 nm infrared laser, Iris Medical Inc., Mountain View, CA, USA) (right eye 1123 spots, left eye 925 spots;400 msec, 400 mW). One-week post laser, there was reduction in vascular tortuosity and exudative retinal detachment in the right eye. There was complete resolution of exudative retinal detachment with a nasal falciform fold at 1-month follow-up [Fig. 1c]. The subretinal exudates resolved over a 3-month period with submacular scar. The left eye changes resolved completely without any sequelae. The infant shows a stable clinical course at 6 months [Fig 1d]. The present case had a predominant exudative response in contrast to the usual proliferative retinopathy seen in majority of cases of IP. These unusual findings are similar to a rare case described previously, which postulated these changes as an inflammatory chorioretinitis.[3] The exact etiology of these changes was unknown and the outcome not described. Subsequently, subretinal exudation containing melanin laden macrophages and lipofuscin was documented in eyes enucleated for total retinal detachment in IP.[4] The etiology of the neovascular retinopathy is more clear, which may result due to oxygen insufficiency caused by peripheral retinal non-perfusion.[2] The extensive exudation seen in the present case appears similar to other disorders like familial exudative vitreo-retinopathy and Coats disease with avascular retina and an abnormal capillary bed. Similar to these disorders, laser photocoagulation was successful in resolution of exudation. A previous study reports successful outcome after laser photocoagulation for proliferative retinopathy of IP.[5] In conclusion, exudative retinopathy in IP is uncommon and can be successfully treated with laser photocoagulation of peripheral avascular retina.