Journal Article

Never forget the adrenal glands: a case report on ibrutinib and the endocrine system

Venu, Maya, Yeoh, Megan Li Yuen, Abouibrahim, Mahmoud

2025

Overview

An 83-year-old man presented to the acute take feeling generally unwell, with reduced mobility, pedal oedema and feeling cold. He lived with his wife, who assisted with his activities of daily living, but otherwise he could still mobilise with a frame. In the emergency department, he had puffy face with swollen hands and bradycardia; bloods showed normal potassium but low sodium and sugars. His thyroid function test found low free T4 but normal levels of thyroid-stimulating hormones. He was given 100 mg intravenous (IV) hydrocortisone with both oral and IV glucose replacement to treat the hypoglycaemia. He was also given IV normal saline. There were some suspicion of adrenal insufficiency. However, because he had background of mantle cell lymphoma, it was thought that progression of his lymphoma was the cause of his lymphoedema, while the hyponatraemia and hypoglycaemia could be the result of poor oral intake. A computed tomography (CT) scan of his neck, chest, abdomen and pelvis was requested. Following post take, it was discussed with his wife that he was too unwell and may not survive the admission. Given that he appeared drowsier throughout the following days, he was referred to the palliative team because prognosis was thought to be days to months. Nevertheless, when the CT scan reported as stable disease, Haematology reviewed him and felt that the deterioration was unrelated to his lymphoma. Thoughts were instead focused on possible heart failure leading to his hyponatraemia and fluid overload state. As he continued to have episodes of hypotension and hypoglycaemia, on Day 4 of his admission, the team reconsidered adrenal insufficiency and decided to give further IV hydrocortisone. It was then when he started to improve. A short Synacthen® test was done and confirmed adrenal insufficiency. He was subsequently referred to the Endocrinology team, who advised also giving levothyroxine and performing magnetic resonance imaging (MRI) pituitary. MRI pituitary eventually found pituitary haemorrhage and he was referred to the Ophthalmology and Neurosurgery teams, who discussed his case in their multidisciplinary team meeting. Ultimately, it was determined that the ibrutinib used to treat his mantle cell lymphoma was likely the cause of his pituitary haemorrhage, causing hypothyroidism and adrenal insufficiency. He made a good recovery after being in hospital for 29 days and was discharged home. He is still under Endocrinology follow-up and his ibrutinib continues to be on hold. He has not been on any lymphoma treatment but is still followed-up by Haematology. The last we heard; he was planning on going on holiday overseas. Ibrutinib is a tyrosine kinase inhibitor and a type of targeted drug for cancer.1 It inhibits tyrosine kinases, which are involved in angiogenesis and cell proliferation.2 Hence, it is useful for cancer when cell proliferates uncontrollably.3 However, because it is a relatively new drug, its side effects are still being studied. So far only one case report, published in 2020, reported ibrutinib causing endocrinological side effects.4 Given that we have now seen another case in a district general hospital, it is important to raise awareness to ensure that it is never missed.

• Publisher: Elsevier Ltd,Elsevier