Endocrine Abstracts

Introduction: Lymphocytic hypophysitis is a rare autoimmune disease predominantly affecting females in the antepartum and postpartum period. It is characterized by destruction and lymphocytic infiltration of predominantly adenohypophysis with various degrees of hypopituitarism. Posteriour pituitary gland involvement is rare but has been reported. We report a case of a 32 year old lady who presented with diabetes insipidus and hypoadrenalism.
Case: A 32 year old lady complained of polydipsia and polyuria at 7 months gestation but had an otherwise uncomplicated pregnancy. She subsequently presented at 9 weeks post partum with worsening polydipsia and polyuria, generalized arthralgia and weakness. Random cortisol was <30nmol per litre and cranial diabetes insipidus was confirmed on water deprivation testing. MRI pituitary showed a 2cm enhancing pituitary mass causing compression of the optic chiasm on the left side. Visual field testing showed left sided nasal field defect. The patient underwent trans-sphenoidal pituitary exploration and histology confirmed severe lymphocytic hypophysitis with fibrosis. Subsequent dynamic pituitary function testing showed growth hormone and gonadotrophin deficiencies. 5 year follow up reveals the patient to be medically stable. Medications include nasal DDAVP spray, deltacortril, growth hormone and oestrogen replacement in the form of the oral contraceptive pill. Follow up MRI pituitary showed no evidence of disease recurrence.
Conclusion: Lymphocytic hypophysitis should be considered in the differential diagnosis of females with pituitary enlargement presenting in the peripartum period. Close monitoring for multiple hormone deficiencies is indicated in this condition.