Sir,

We read with great interest the report1 describing an isolated case of crystalline maculopathy in a North-East African individual from Egypt. West African Crystalline Maculopathy (WACM) has only been seen in a single population isolate to date (The Yoruba and Igbo tribes of West Africa), making a genetic predisposition likely. While the genetic makeup of Egyptians is interesting, genetically, they are very different to the West Africans; a combination of geographical location and history of modern and ancient migration have resulted in a complex and diverse gene pool of European, Middle Eastern, and African genetic characteristics.2

The central foveal crystalline deposits in this case are indeed interesting; however, we believe it differs from the described features of WACM. Firstly, the appearance and distribution of the crystals are different from that seen with published cases of WACM. Our previously published series, as well as of other authors have shown WACM to consist of intra-retinal crystals (Figure 1),3, 4, 5 whereas, in this case, the crystals appear very localised to the inner retina at the foveola. Commonly in WACM, there is also concurrent co-pathology that affects the blood-retinal barrier such as diabetes.

Figure 1
figure 1

Fundus photograph demonstrating West African Crystalline Maculopathy, with OCT image showing retinal localisation of crystals.

Full size image

The authors have described and excluded other causes of crystalline deposits in this report; therefore, although we believe this case does not exhibit the recognised changes seen in WACM, it could be a different phenotype. However, it is difficult to make further comment from just a single index case. We now have accumulated an unpublished case series of over 50 patients with WACM, who all, without exception, originate from West Africa, and exhibit the described features. It is premature to consider a new label for this condition from just a single albeit interesting case.