A 7-year-old boy with central diabetes insipidus presenting with thickened pituitary stalk and anti-rabphilin-3A antibody positivity.

Objectives: A highly invasive pathological diagnosis is necessary to differentiate central diabetes insipidus (CDI) with a thickened pituitary stalk. Lymphocytic infundibulo-hypophysitis (LIH) due to autoimmune involvement of the pituitary stalk is a differentiating disease, and anti-rabphilin-3A antibody (Rab3A-Ab) positivity was recently reported.

Case Presentation: A 7-year-old boy was diagnosed with CDI after having polyuria for two months.