A systematic review of cases of West African crystalline maculopathy.

Abstract

West African crystalline maculopathy (WACM) is, reportedly, a rare condition whose aetiology remains unclear. This study aims to describe the epidemiology, summarizing the identified risk factors and clinical characteristics of cases of WACM, with the goal of highlighting presentation patterns and the clinical course of the condition. A comprehensive PubMed, Medline, EMBASE, Web of Science, OMIM and Google scholar search of all articles written in English, and non-English language articles with abstract translated to English on WACM was carried out. Only full case reports and series were included. Data reviewed included epidemiology, risk factors, clinical presentations, imaging characteristics, management and prognosis of WACM. Information on the location of the study was also extracted. Ten studies - seven case reports and three case series - comprising of 30 patients were included. The patients were from West, Central and North-east Africa, with all the studies carried out in North America and Europe. The majority of the patients (76.7%) had diabetes mellitus, 80% had a vascular retinopathy (diabetic retinopathy, sickle cell retinopathy, familial exudative vitreoretinopathy and branch retinal vein occlusion) and 50% had macular oedema. There was no report of associated visual impairment or retinal degeneration. Clinical improvement in the number of crystals was documented in two cases with retinal laser photocoagulation for associated vascular retinopathies. Clinical observation was employed by most clinicians. West African crystalline retinopathy is a seemingly innocuous condition affecting black or African people, who were also born in Africa. The majority of the patients have a vascular retinopathy. Longitudinal studies, particularly in Africa, may be required to elucidate the aetiology, as well as the long-term prognosis, of the crystals.