Endocrinology — MCQs

Question 311: Brain tumor causing hypernatremia in children is typically associated with which of the following?

• A. Medulloblastoma
• B. Cerebellar astrocytoma
• C. Brain stem glioma
• D. Craniopharyngioma (Correct Answer)

Explanation: ***Craniopharyngioma*** - **Craniopharyngiomas** are benign tumors arising from Rathke's pouch remnants, often located near the **hypothalamus** and **pituitary gland**. - Their proximity to these structures can disrupt **ADH secretion** and regulation of water balance, leading to **diabetes insipidus** and subsequent **hypernatremia** in children. *Medulloblastoma* - **Medulloblastomas** are aggressive malignant tumors of the **cerebellum**, primarily impacting motor coordination and balance. - They typically do not directly affect the **hypothalamic-pituitary axis** to cause hypernatremia. *Cerebellar astrocytoma* - **Cerebellar astrocytomas** are common **pediatric brain tumors** usually located in the posterior fossa. - While they can cause **hydrocephalus** due to mass effect, they are not typically associated with disorders of sodium regulation or hypernatremia. *Brain stem glioma* - **Brain stem gliomas** affect vital functions controlled by the brain stem, such as breathing, heart rate, and cranial nerve function. - They are not commonly linked to the disruption of **fluid and electrolyte balance** like hypernatremia.