Endocrine Abstracts

Case: A 68-year-old gentleman presented to A&E with a 6-month history of physical and cognitive decline, on a background of learning disability, autism spectrum disorder and schizophrenia. His mobility had deteriorated from being mobile without aid, to mobilising with a stick and having multiple falls, with associated cognitive decline. His care needs had increased from 4 carer visits/day to requiring 24-hour care. He had no history of headaches, or visual disturbance.

Investigations: Admission bloods showed normal inflammatory markers, electrolytes, liver function and PSA. Free T4 was 3.6 pmol/l (normal range 10.5-24.5 pmol/l), with an inappropriately normal TSH of 2.05mU/L (NR 0.27-4.2mU/l), consistent with secondary hypothyroidism. CT Brain demonstrated a 25mm sellar lesion. Pituitary MRI was of suboptimal quality due to movement artefact and confirmed a 31x16x16mm pituitary macroadenoma, with no optic chiasm involvement. Anterior pituitary function tests demonstrated panhypopituitarism, with ACTH, growth hormone and gonadotropin deficiencies: 9am Cortisol 25nmol/l (NR 133-537nmol/l), ACTH 4ng/L (NR <50ng/l), FSH 1.8u/L (NR 1.5-12.4u/l), Testosterone <0.5nmol/l (NR 6.7-25.7nmol/l), IGF1 43ug/L (NR 38.6-230.8ug/l). Prolactin was mildly increased (560mU/l; NR 0-323 mU/l) in keeping with antipsychotic medication use and stalk effect. FBC demonstrated a mild normocytic anaemia consistent with testosterone deficiency.

Treatment: The patient was commenced on physiological hydrocortisone replacement, followed by levothyroxine and testosterone gel. Within a few weeks, his carers had noticed an improvement in his mobility and cognition and reduced falls. He is scheduled for repeat pituitary imaging in 12 months.

Conclusion and discussion points: Hypopituitarism typically presents with non-specific symptoms including fatigue and erectile dysfunction in men. The diagnosis can be particularly challenging in patients with learning disabilities. This case highlights the importance of considering a diagnosis of hypopituitarism in adults with learning disabilities presenting with physical and cognitive decline, as treatment reduces morbidity and mortality and improves physical and cognitive function.