A 10-year-old boy with dystonia, expression-less facies, and tremors referred for ophthalmic examination.

A 10-year-old boy presented to the pediatric department with an inability to walk without help for 1 month and an abnormal posture of the right upper limb for 6 months. Systemic findings included coarse tremor and dystonia of the right upper limb with choreoathetoid movements of the left upper limb. He had an expression-less facies and cognitive decline. He was referred for ophthalmic examination. Slit-lamp photographs of the anterior segment of both eyes are depicted in Figure 1. The fundus was normal in either eye.

Figure 1

The anterior segment findings of the patient

Questions

Describe the findings in Figure 1

What ophthalmic examination will help in confirmation of the clinical finding?

Answers

Figure 1 shows peripheral circumferential golden-yellow Keyser–Fleischer (KF) ring [left image, within arrowheads marked in Figure 2] in both corneas. The lens was clear in either eye. Direct focal examination of the cornea by a thin slit beam showed the golden discoloration to be located at a deep corneal level [at the level of Descemet's membrane, right image-Figure 2 arrowhead]

Figure 2

Labeled diagram of Figure 1 shows the Keyser–Fleischer ring (arrowheads)

Though in this case KF rings were visible on slit-lamp examination, a detailed gonioscopy [Figure 3, between arrowheads] confirms that the golden ring is discoloration of the Descemet's membrane and the discoloration typically ends just anterior to the Schwalbe's line [black arrowhead, Figure 3]. This child had reduced ceruloplasmin level of 8.45 mg/dl (25–63 mg/dL). Ultrasound of the abdomen revealed coarse echotexture of the liver. Magnetic resonance imaging of the brain revealed T2 hyperintensities at the basal ganglia and thalamus, with mild involvement of the midbrain/pontine tegmentum, periaqueductal gray matter, and frontal and parieto-temporal lobes. A diagnosis of Wilson's disease was made by the pediatrician considering the finding of KF ring, Parkinsonian features, and findings of the investigations.

Figure 3

Goniophotograph showing an open angle of the anterior chamber, a few iris processes, and the golden yellow discoloration (between arrowheads) is seen extending just anterior to the Schwalbe’s line (black arrowhead)

Discussion

Wilson's disease is caused by a genetic defect in ATP7B gene, leading to an abnormality in the transfer of copper into the Golgi apparatus where copper combines with proteins such as ceruloplasmin and cytochrome oxidase.[1] This results in an increased copper load, which causes damage to the hepatocytes. Once the copper-binding sites at the liver are saturated, the copper gets deposited in various organs including the brain (basal ganglia), liver, eye (Descemet's membrane, KF ring), and the kidney. The ceruloplasmin becomes unstable with a short half-life, and the serum ceruloplasmin level gets reduced. KF ring is a manifestation of Wilson's disease due to deposition of copper in the peripheral Descemet's membrane. It usually starts in the superior and inferior cornea at the Schwalbe's line. Earliest stages may require a detailed gonioscopy for detection. KF ring may also be seen in other conditions including primary biliary cirrhosis, cryptogenic cirrhosis, intraocular copper foreign body, cholestatic cirrhosis, and chronic active hepatitis.[1] Copper deposit at the Descemet's membrane may also be seen in multiple myeloma. The KF ring may disappear after chelation therapy or liver transplant.[1] However, a large study found that KF ring was independent of both the stage of Wilson's disease and the effectiveness of the chelation therapy.[2]

Conclusion

Ophthalmic examination may provide critical clues to the diagnosis of various neurological disorders including Wilson's disease.[3]

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.