Diencephalic Syndrome: Clinical Features, Pathophysiology, and Long-Term Outcomes

Area of Science:

• Pediatric Endocrinology
• Pediatric Oncology
• Neuro-oncology

Background:

• Diencephalic syndrome (DS) is a rare pediatric disorder characterized by failure to thrive despite adequate caloric intake.
• It predominantly affects infants under 12 months and is diagnostically challenging.
• Russell first described this condition, often linked to hypothalamic-chiasmatic gliomas.

Purpose of the Study:

• To comprehensively review the clinical presentation, pathophysiology, diagnosis, and outcomes of Diencephalic syndrome.
• To highlight the importance of early recognition and multidisciplinary management.

Main Methods:

• Comprehensive literature review.
• Examination of clinical presentation, pathophysiology, associated pathology, diagnostic approaches, and long-term outcomes.

Main Results:

• DS presents in infancy with cachexia, preserved height, hyperactivity, and visual pathway involvement.
• Low-grade hypothalamic-chiasmatic gliomas, especially pilocytic astrocytomas, are the main cause.
• Survival exceeds 90% at five years, but significant long-term morbidities like visual impairment and endocrine deficiencies are common.

Conclusions:

• Early recognition of Diencephalic syndrome is crucial to prevent irreversible complications, particularly visual loss.
• Chemotherapy is the preferred first-line treatment for underlying gliomas, improving survival and reducing radiation toxicity.
• Survivors require lifelong monitoring and intervention for sequelae such as hypothalamic obesity.