Ocular cues to a larger picture!

A 23-year-old male presented with a gradual, painless diminution of vision in both eyes for the last 5 months. The uncorrected visual acuity was 20/30 in both eyes with intraocular pressure of 14 mmHg. Anterior lenticonus was noted in both eyes [Fig. 1a and b]. Dilated fundus examination was normal apart from blunted foveal reflex in both the eyes [Fig. 1c and d]. The patient had no known systemic illness and was not on any systemic medication.Figure 1: Slit lamp photographs reveal anterior lenticonus. (a and b) Widefield images blunted foveal reflex in both eyes. (c and d)What Would be Your Next Step? Nephrology referral Optical coherence tomography macula Fundus autofluorescence Fluorescein angiography. Findings Macular OCT was performed, and bilateral temporal thinning was noted [Fig. 2a and b]. Fundus autofluorescence was within the normal limits.Figure 2: Macular OCT reveals bilateral thinning of the temporal macula. (a and b)Diagnosis Alport syndrome Correct Answer B The presence of bilateral anterior lenticonus and typical retinal findings of temporal retinal thinning raised the possibility of a diagnosis of Alport syndrome. The patient was also advised to undergo a detailed nephrology examination to rule out the possibility of underlying renal disease and an ENT examination to look for hearing abnormalities. Discussion Alport syndrome is a hereditary disease caused by mutations in the COL4A3, COL4A4, or COL4A5 genes, which affect the production of Type IV collagen, an important structural component of basement membrane, which results in progressive nephropathy, variable sensorineural hearing loss, and variable ocular sequelae.[1] Ocular features are a consequence of perturbation of Type IV collagen networks in the cornea, lens capsule, Bruch’s membrane, and internal limiting membrane. It is associated with fleck retinopathy and macular thinning.[2] Rare ocular findings include posterior polymorphous corneal dystrophy and macular hole, which impair visual acuity. Kapoor et al.[3] reported flecks to be better visualized on red-free imaging as a ring of fine white stippling around the macula. They also found temporal enlargement of the foveal avascular zone of the superficial retinal plexus on optical coherence tomography angiography. The occurrence of temporal retinal thinning is more common than other ocular abnormalities and is independent of other ocular features in Alport syndrome patients. Ahmed et al.[4] generated a temporal thinning index (TTI) to analyze temporal retinal thinning, which is diagnostic for X-linked Alport syndrome in men. Anterior lenticonus, an abnormality in the shape of the lens, affects about 15–20% of patients with X-linked and autosomal recessive Alport syndrome.[1] Ocular examination is of vital help to support the diagnosis of Alport syndrome. Ocular anomalies can also determine the prognosis of nephropathy.[1] Declaration of patient consent The authors certify that they have obtained all appropriate patient consent forms. In the form, the patient(s) has/have given his/her/their consent for his/her/their images and other clinical information to be reported in the journal. The patients understand that their names and initials will not be published and due efforts will be made to conceal their identity, but anonymity cannot be guaranteed. Financial support and sponsorship: Nil. Conflicts of interest: There are no conflicts of interest.