Endocrine Abstracts

Background: Testosterone replacement therapy (TRT) is a well-established intervention for confirmed male hypogonadism. Within the NHS and other regulated healthcare systems, prescribing is guided by stringent biochemical and clinical criteria, ensuring that treatment is reserved for individuals with unequivocal androgen deficiency and symptomatic burden. This evidence-based framework promotes safety, therapeutic efficacy, and long-term monitoring. In contrast, private prescribing pathways may lack standardised thresholds and oversight, allowing initiation of TRT in patients with borderline biochemical profiles or non-specific symptoms. While this may offer perceived flexibility, it carries significant risks—including inappropriate treatment, adverse effects such as erythrocytosis, and psychological dependence.

Case Presentation: A 43-year-old man was referred to the endocrine clinic with longstanding depressive symptoms, reportedly familial following maternal suicide. His mood and energy levels deteriorated significantly during the COVID-19 pandemic. Initial biochemical evaluation revealed borderline gonadotropin levels (FSH 1.3 IU/l, LH 2.4 IU/l) and low-normal total testosterone (6.8–7.8 nmol/l), with SHBG of 42 nmol/l and calculated free testosterone of 0.22 nmol/l. He reported infrequent morning erections and was not sexually active, limiting assessment of libido. Hematocrit was elevated at 51%, with normal thyroid function (TSH 2.5 mIU/l, FT4 16 pmol/l) and prolactin (345 mIU/l). Bone mineral density and hemoglobin were within normal limits. Despite not meeting NHS criteria for TRT, he initiated therapy via a private clinic, with dose escalation over two years. He reported marginal improvement in energy but no significant mood benefit. His antidepressant dosage increased during this period. Multiple attempts to discontinue TRT were unsuccessful due to disabling fatigue and mood deterioration. He now presents with persistent erythrocytosis and psychological dependence on exogenous testosterone.

Discussion: This case highlights the diagnostic ambiguity and therapeutic complexity of managing borderline androgen deficiency in the context of primary affective disorder. The patient’s expectation that TRT would resolve depressive symptoms was unmet, and withdrawal proved destabilising. The development of erythrocytosis underscores the risks of long-term TRT without clear biochemical indication. This case reinforces the importance of multidisciplinary assessment and cautious prescribing, particularly outside established guidelines, and raises important questions about the role of testosterone in mood regulation and the limitations of private practice in managing endocrine-psychiatric overlap.