What is the appropriate workup for a 75-year-old male with elevated testosterone?

Workup for Elevated Testosterone in a 75-Year-Old Male

Elevated testosterone in a 75-year-old male is highly unusual and requires immediate investigation to exclude androgen-secreting tumors of the adrenal glands or testes, which are the primary concern in this demographic.

Initial Laboratory Assessment

The first step is to confirm the elevation with a repeat fasting morning total testosterone measurement using a validated assay to exclude laboratory error or physiologic variation. Once confirmed elevated (typically >2x upper limit of normal for age), proceed with the following workup:

Essential Laboratory Tests

• DHEAS (Dehydroepiandrosterone sulfate): This is the critical discriminating test 1

  • DHEAS >600 µg/dl (16,000 nmol/l) strongly suggests an androgen-secreting adrenal cortical adenoma and mandates urgent abdominal imaging 1
  • Normal DHEAS shifts suspicion toward testicular source

• SHBG (Sex Hormone Binding Globulin): Essential for interpretation 1

  • Paradoxically elevated SHBG with high testosterone may indicate medication effects (tamoxifen, raloxifene), hyperthyroidism, or liver disease (particularly cirrhosis with portal hypertension) 1
  • This pattern is important as it changes the differential diagnosis entirely

• LH and FSH: To determine if testosterone elevation is gonadotropin-dependent or autonomous

Imaging Studies

If DHEAS is markedly elevated (>600 µg/dl), obtain abdominal CT or MRI immediately to evaluate for adrenal adenoma or carcinoma 1. These tumors are often associated with hypercortisolism and require urgent surgical evaluation.

If DHEAS is normal, obtain testicular ultrasound to evaluate for Leydig cell tumors or other testicular masses that can autonomously produce testosterone.

Additional Considerations

Medication Review

Carefully review all medications, particularly:

• Drugs with estrogenic effects that raise SHBG (creating a pattern of elevated total testosterone with high SHBG) 1
• Exogenous testosterone or anabolic steroid use (intentional or inadvertent)

Thyroid and Liver Function

• TSH and free T4: Hyperthyroidism can elevate SHBG and create misleading total testosterone elevations 1
• Liver function tests: Cirrhosis and portal hypertension can cause similar SHBG-mediated patterns 1

Critical Pitfalls to Avoid

1. Do not dismiss elevated testosterone as "normal aging variation" - testosterone naturally declines with age, so elevation is pathologic until proven otherwise

2. Do not delay imaging if DHEAS is markedly elevated - adrenal tumors can be malignant and require prompt intervention 1

3. Always measure DHEAS - this single test is the most important discriminator between adrenal and gonadal sources 1

4. Consider factitious elevation from SHBG - check SHBG and calculate free testosterone if total testosterone is elevated but clinical picture doesn't fit 1

Algorithmic Approach

Confirmed elevated total testosterone (repeat testing)
    ↓
Measure DHEAS + SHBG + LH/FSH
    ↓
DHEAS >600 µg/dl → Urgent abdominal CT/MRI (adrenal tumor)
    ↓
DHEAS normal + low/normal LH → Testicular ultrasound (testicular tumor)
    ↓
High SHBG pattern → Check TSH, liver function, medication review

The evidence base for this approach comes primarily from hyperandrogenism guidelines 1, though these were developed for women. The same pathophysiologic principles apply to men, where autonomous androgen production from tumors follows identical biochemical patterns. The key difference is that elevated testosterone in elderly men is even more concerning given the expected age-related decline in normal physiology.