Recent case reports highlight the role of early cataracts in identifying rare genetic disorder

Early-onset cataracts can serve as a crucial diagnostic clue in identifying cerebrotendinous xanthomatosis (CTX), a rare but treatable metabolic disorder caused by mutations in the CYP27A1 gene. While CTX often presents with diverse and seemingly unrelated symptoms, including chronic diarrhea and progressive neurological decline, bilateral juvenile cataracts may be one of the earliest manifestations. This report highlights 2 case studies in which early cataracts played a key role in the diagnostic process, underscoring the importance of recognizing this ophthalmic finding as a potential marker for systemic disease.

The first case study focuses on a 21-year-old male who presented with chronic diarrhea since childhood and was later diagnosed with bilateral juvenile cataracts. These seemingly unrelated symptoms were ultimately attributed to CTX. The report emphasizes the importance of considering a unifying diagnosis when patients exhibit multiple unexplained symptoms, as early detection and treatment of CTX are crucial to prevent progressive neurological deterioration.​

​The second case study details the diagnostic journey of a 33-year-old male who exhibited a 6-year progression of gait disturbances and had a history of bilateral juvenile cataracts operated on at age 19. Neurological examination revealed spastic gait, brisk reflexes, ankle clonus, upgoing plantar responses, hypometric saccades, mild cerebellar ataxia, dysmetria, and impaired proprioception and vibration sense, indicating upper motor neuron involvement and posterior column dysfunction. Brain MRI showed increased T2 signals in the dentate nuclei, while spinal MRI indicated diffuse T2 hyperintensities in the cervical and upper thoracic regions. Genetic testing confirmed mutations in the CYP27A1 gene, leading to the CTX diagnosis.

Reference
Risto MI, Sobrosa P, Vilela M, et al. Juvenile Cataract and Chronic Diarrhea: A Single Etiology. Cureus. 2025;17(2):e79760. doi: 10.7759/cureus.79760. PMID: 40161147; PMCID: PMC11954438.

Marta VL, Tripthi S, Oksana S. A case report of Cerebrotendinous Xanthomatosis: Progressive gait difficulties and juvenile cataracts in a 33-year-old male. Parkinsonism Relat Disord. 2025;107259. doi: 10.1016/j.parkreldis.2024.107259. Epub ahead of print. PMID: 39809686.