Sir,

Chandra and colleagues1 rightly wonder about other possible causes for ectopia lentis seen in our patient with Sturge–Weber syndrome (SWS).2 Because of space constraints, we did not report on the full differential diagnosis of ectopia lentis.3 As we noted, our patient denied even a remote history of trauma; her normal mentation and body habitus, and her ocular examination and the unilaterality of her condition made several possible diagnoses unlikely, including ectopia lentis and pupillae, homocystinuria, Weill–Marchesani syndrome, sulfite oxidase deficiency, and hyperlysinemia. In addition to the investigations included in our report, she reported no family history of Marfan syndrome, nor of any other family members with her condition, including her two school-aged children. In addition, no clinical evidence of pseudoexfoliation, retinitis pigmentosa, buphthalmos, megalocornea, chronic uveitis (other than that associated with her condition), or ocular syphilis, nor aniridia was seen.

To our regret, we did not perform any genetic studies, and our patient may have separate mutations resulting in both SWS and isolated ectopia lentis. Indeed, that is likely, given the paucity of reports associating ectopia lentis and SWS. However, reports of unilateral isolated ectopia lentis are similarly rare;4 this entity is usually familial and bilateral, at least those due to known genetic mutations.5 We welcome further research into the pathogenetic mechanisms of ectopia lentis.