Sitosterolemia Presenting as Lipid Keratopathy and Xanthomas

Area of Science:

• Genetics
• Metabolic Disorders
• Pediatrics

Background:

• Sitosterolemia is a rare autosomal recessive lipid metabolism disorder.
• It is often misdiagnosed as familial hypercholesterolemia, especially in pediatric patients.
• Presentation can be varied, including corneal deposits and xanthomas.

Purpose of the Study:

• To report a case of sitosterolemia presenting with ophthalmologic findings.
• To emphasize the importance of raising clinical suspicion for sitosterolemia among pediatricians.
• To highlight the differences in management between sitosterolemia and familial hypercholesterolemia.

Main Methods:

• Case report of a 7-year-old girl with corneal deposits and xanthomas.
• Initial diagnosis of familial hypercholesterolemia with statin therapy.
• Negative genetic testing for familial hypercholesterolemia.
• Expanded genetic panel revealing ABCG5 gene variants.
• Sterol analysis showing elevated phytosterols.

Main Results:

• The patient was diagnosed with sitosterolemia based on genetic and sterol analysis.
• She showed partial response to statin therapy.
• Treatment with dietary restriction and ezetimibe was initiated.
• No coronary artery calcification was observed.

Conclusions:

• Sitosterolemia requires high clinical suspicion in pediatric cases, even with initial presentation to other specialties.
• Accurate diagnosis is critical as management differs from familial hypercholesterolemia.
• Awareness among pediatricians is vital for timely and correct intervention.