Pituitary stalk Langerhans cell histiocytosis


  • A 9-year-old girl who was previously diagnosed with Langerhans cell histiocytosis.
  • Previous assessment showed bony and pulmonary involvement.
  • Recently she also developed diabetes insipidus.

MRI findings:

  • The MRI in sagittal (a) T1-weighted, (b) T2-weighted and (c) T1 post gadolinium images
  • Abnormal thickening of the pituitary stalk (white arrow).
  • The thickened pituitary stalk shows homogenous vivid enhancement post contrast.
  • There is absent of normal posterior pituitary bright spot on T1W-images.
  • Pituitary gland is normal in size.

Diagnosis: Pituitary stalk Langerhans cell histiocytosis


  • Langerhans cell histiocystis (LCH) is a rare disease with multisystem/multiorgan involvement.
  • The incidence is more common in children. Estimated incidence of 5 per million children and 1-2 cases per million adult population.
  • The most common CNS manifestation in LCH is infiltration of the hypothalamic-pituitary region by LCH granuloma. This frequently results in diabetes insipidus.
  • Diabetes insipidus may occur before, simultaneously and after the other multisystem manifestations, making the diagnosis difficult.
  • Since the etiological diagnosis of central DI with thickening of the pituitary stalk may not be apparent at the time of detection of DI, serial imaging and close follow-up of these patients to reach a conclusive diagnosis is necessary and mandatory to avoid the attendant risks of pituitary stalk biopsy
  • Radiological manifestations of the disease include thickening of pituitary stalk more than 3 mm, with loss of physiological hyperintense signal in posterior pituitary on T1W images signifying loss of ADH storage granules. This may progress to a mass lesion involving pituitary and hypothalamus.
  • Other less common CNS manifestations are neurodegenerative changes and intra axial mass lesions.
Author: radhianahassan