Endocrine Abstracts

History: A 36 year old gentleman was referred to the endocrine clinic with symptoms of fatigue, absent libido and erectile dysfunction. He had a previous history of pulmonary sarcoidosis in 2000 and he was taking no medications. Examination revealed a known Right sided Horner’s syndrome and no other abnormality.

Investigations: Testosterone 1.8 nmol/l, FSH and LH<0.5, Prolactin 798 mU/l, Cortisol 507 nmol/l, ACE 67 (47–60 IU/l), CSF protein 2.99 g/l.

The results confirmed secondary hypogonadism. In view of the past medical history of pulmonary sarcoidosis the initial differential diagnosis included neurosarcoidosis. MR imaging showed intense enhancement of the pituitary stalk, hypothalamus, and leptomeninges and left third and fifth cranial nerves suggestive of neurosarcoidosis.

His case and imaging was discussed at a Tertiary centre neuroradiology MDT and the conclusion was that Neurosarcoidosis was the most likely diagnosis and biopsy would not be necessary at this time.

The treatment for Neurosarcoidosis is steroid therapy and the decision to treat is based upon the presence of neurological signs and evidence of progression. The patient declined steroid therapy initially and commenced androgen replacement. He was subsequently admitted with confusion and vomiting. A repeat MR scan was unchanged. Polyuria was suggestive of diabetes insipidus. Desmopressin and steroid therapy was now initiated with a dramatic clinical improvement.

Neurosarcoidosis is an uncommon condition affecting 5% of patients with sarcoidosis. Pituitary and hypothalamic involvement is rarely seen in only 0.5% of cases. Despite this rarity our case highlights the importance of considering the diagnosis in patients with a history of sarcoidosis.