Endocrine Abstracts

Introduction: Lymphocytic Hypophysitis (LH) is an autoimmune endocrinopathy characterised by extensive infiltration of the anterior pituitary gland with chronic inflammatory cells, thus causing pituitary expansion and a variable degree of hypopituitarism closely mimicking the features noted in pituitary adenoma and seen most frequently in women. The aetiology has a general preponderance of occurring at the end of gestation or during the early postpartum period.

Case history and investigations: We report a case of a 49 year female, with a background of Hypertension (HTN), Asthma and Gastric Reflux, who presented to our Endocrine Clinic with a 4 to 5-year history of lethargy, headaches, menstrual irregularities and gradual weight gain accompanied with intermittent visual blurring.

Blood Pressure 178/108 mm Hg.

Bloods-TSH-3.26 mu/l (0.2–5.0), Free T4 – 8.1 pmol/l (10–24), T3 – 1.3 nmol/l (1.3–3.1) FSH – 0.88 u/l, LH – <0.50 u/l, Serum Oestradiol – 17 Beta – 28 pmol/l, Prolactin – 882 mu/l (150–812)

Coeliac Screen – Negative

Renal functions, Electrolytes- Historically Normal

On the basis of the Biochemical results and clinical symptoms, a baseline Visual field assessment from Ophthalmology and MRI were requested. Visual assessment conducted by ophthalmology revealed bilateral visual acuity to be 6/9, with no remarkable findings or changes in the Optic Discs. MRI reported as findings consistent with Lymphocytic Hypophysitis with the differential diagnosis of Pituitary Adenoma being less likely based on MRI criteria.

Results and treatment: Taking into account the findings, this case was brought forth and discussed in our Endocrine MDT with joint input from the Radiology, Surgical and Endocrine teams. The likely diagnosis of Lymphocytic Hypophysitis was confirmed. A Short Synacthen test is being organised for the patient, depending on the results of which, Hormone replacement (Steroid replacement first) +/−implementation of immunosuppressive therapy would be given careful consideration.

Conclusion and points for discussion: Lymphocytic Hypophysitis displays a close association to pregnancy, approximately 70% of cases in women presenting during pregnancy or postpartum, which makes this case extremely unique in nature. Understanding and differentiating the Radiological manifestations of Lymphocytic Hyophysitis (LH) and Pituitary Adenoma on the basis of MRI criteria is of paramount importance, since the management plans vary based on the underlying aetiology. This case brings to the forefront that LH is not isolated solely to the pregnant or peri-partum population and the importance of MRI criteria used to differentiate between LH and Pituitary Adenoma. Due to the complexity in diagnosis and differentiation, discussion in a MDT setting is highly recommended.