Endocrine Abstracts

Introduction: Klinefelter syndrome (KS) is the most common chromosomal abnormality in males, typically presenting with hypogonadism, tall stature, and learning or behavioural difficulties. Despite affecting 1 in 600 males, KS remains significantly underdiagnosed due to its variable presentation, particularly in milder forms such as mosaicism. Diagnosis requires genetic testing, and management primarily involves testosterone replacement therapy (TRT) and fertility support. Early diagnosis and holistic care addressing both physical and neurodevelopmental symptoms are crucial for improving long-term outcomes.

Aims: • To investigate the diagnosis and management of KS including clinical, genetic, and biochemical tools, timing of diagnosis, and current practices in South and West Wales.

• To evaluate hormone monitoring and treatment strategies.

Methods: A retrospective review of 46 patients with KS was conducted using departmental databases. Clinical data, endocrine parameters, TRT initiation, and fertility discussions were extracted from records and analysed using Microsoft Excel.

Results: Of the 46 patients reviewed, 28% were diagnosed antenatally, primarily via amniocentesis. Most postnatal diagnoses occurred before age 5 due to learning, developmental, or behavioural difficulties. Only 11% were diagnosed during adolescence, despite this being a typical time for KS presentation. 56% of patients received TRT, typically starting at a mean age of 15.6 years. Biochemical hypogonadism was the most common indication, with most patients showing elevated FSH/lH and low testosterone levels. 10 patients were started on TRT for a combination of clinical and biochemical hypogonadism, while 2 patients were started on TRT for only clinical hypogonadism. Fertility discussions were documented in 67% of cases, but only 25% were referred to fertility services, highlighting a gap in care pathways.

Conclusions: KS is often underdiagnosed due to its varied presentation; early diagnosis, timely TRT, and further research are vital to improve outcomes and support, particularly around fertility and long-term care. Early KS care can be provided by increasing clinical awareness and routine genetic testing in boys with developmental concerns. Standardised, multidisciplinary care pathways should guide hormone monitoring, timely initiation of TRT, and structured transitions to adult care. Psychosocial support, fertility counselling, and patient education are essential.