Abstract
Pituitary infiltration by systemic lymphoma is an exceedingly rare occurrence. Given its high mortality rate, it is crucial to recognize its clinical, biochemical and radiological features in order to provide timely intervention. We present the case of a 26-year-old male with a history of human immunodeficiency virus (HIV) infection who presented to the hospital with severe anemia, persistent fever, weight loss and diarrhea over the previous 4 months. Physical examination revealed a compromised general condition, fever, pallor, hepatomegaly and lymphadenopathy. Cervical lymph node biopsy confirmed Burkitt lymphoma (BL). During hospitalization, the patient developed polyuria, polydipsia, hypernatremia, fluid-resistant hypotension and hypoglycaemia. Corticosteroid therapy was initiated due to suspected adrenal insufficiency, resulting in clinical improvement but exacerbation of polyuria and hypernatremia. Plasma and urinary osmolarity confirmed arginine vasopressin deficiency, and assessment of anterior pituitary reserve revealed hypopituitarism, necessitating hormonal replacement therapy. Sellar magnetic resonance imaging with contrast revealed pituitary infiltration. The patient subsequently developed septic shock and died. BL accounts for approximately 10% of the cases of pituitary infiltration associated with lymphoma. Clinical presentation is heterogeneous, with panhypopituitarism often serving as the initial manifestation. Sellar magnetic resonance imaging plays a pivotal role in the differential diagnosis. Management typically entails chemotherapy, immunotherapy, radiation and hormonal replacement therapy. This case report describes a patient with BL and HIV infection who developed panhypopituitarism due to pituitary infiltration, an exceedingly rare presentation considered a medical emergency.