Kennedy's Disease Initially Manifesting as an Endocrine Disorder

Area of Science:

• Neuroendocrinology
• Genetics
• Neurology

Background:

• Spinal and bulbar muscular atrophy (SBMA), or Kennedy's disease, is an X-linked neurodegenerative disorder.
• It is characterized by motor neuron degeneration and partial androgen insensitivity.
• SBMA typically presents in adulthood with progressive muscle weakness and atrophy.

Purpose of the Study:

• To report a unique case of SBMA presenting primarily with endocrine abnormalities.
• To emphasize the importance of considering SBMA in patients with unexplained endocrine and metabolic disturbances.
• To highlight the diagnostic challenges when neuromuscular symptoms are absent.

Main Methods:

• Case report of a 59-year-old male patient.
• Clinical evaluation including assessment of endocrine and neurological signs.
• Electromyography (EMG) to assess muscle denervation.
• Genetic testing for androgen receptor gene mutations (CAG repeat expansion).

Main Results:

• The patient presented with diabetes mellitus, hypercholesterolemia, testicular atrophy, gynecomastia, and elevated creatine kinase (CK).
• EMG revealed widespread denervation.
• Genetic analysis identified an abnormal 43 CAG repeat in the androgen receptor gene, confirming SBMA.
• The patient lacked a family history and presented without overt neuromuscular complaints.

Conclusions:

• SBMA can present with a pure endocrine phenotype, mimicking other endocrine disorders.
• The absence of typical neuromuscular signs does not exclude SBMA.
• Early genetic testing is crucial for diagnosing SBMA, especially in cases with atypical presentations.