What is the interpretation of a bladder and prostate ultrasound showing normal bladder wall thickness and a prostate volume of 21 mL in an adult male patient presenting with hematospermia?

Interpretation of Bladder and Prostate Ultrasound in Hematospermia

Your ultrasound findings are reassuring and show normal bladder function with a small, normal-sized prostate that is unlikely to be the source of hematospermia. The most common cause in this scenario is seminal vesicle hemorrhage, which cannot be visualized on transabdominal ultrasound 1.

Key Findings Analysis

Bladder Parameters (Normal)

• Normal bladder wall thickness: Your bladder wall is normal, which effectively rules out chronic bladder outlet obstruction or detrusor hyperactivity 2. Normal adult male bladder wall thickness is 3.3 ± 1.1 mm, with values up to approximately 4.5 mm considered within normal limits 2.
• Excellent bladder emptying: Post-void residual of 21 mL is well within normal range (normal <50-100 mL) 3. This indicates no bladder dysfunction or obstruction 3.
• Normal bladder capacity: Pre-void volume of 757 mL is within normal functional capacity 1.

Prostate Parameters (Normal)

• Small prostate volume: At 21 mL, your prostate is significantly smaller than the typical threshold (>30 mL) associated with benign prostatic hyperplasia 1. This small size makes prostatic pathology an unlikely source of hematospermia 1.
• No obstruction: The combination of small prostate volume and minimal post-void residual definitively excludes bladder outlet obstruction as a contributor to your symptoms 1, 3.

Clinical Implications for Hematospermia

What This Ultrasound Rules Out

• Bladder pathology (normal wall thickness and emptying) 1
• Prostatic enlargement or obstruction (21 mL prostate, 21 mL PVR) 1
• Significant bladder dysfunction (excellent emptying) 3

Most Likely Diagnosis

Seminal vesicle hemorrhage is the most probable cause of your hematospermia, which occurs in the majority of cases where transabdominal ultrasound is normal 1, 4. The seminal vesicles are the primary site of bleeding in hematospermia but cannot be adequately visualized with transabdominal ultrasound 1.

Next Steps in Evaluation

If hematospermia persists or recurs, transrectal ultrasound (TRUS) should be your next imaging study 1. TRUS is the first-line imaging modality specifically for hematospermia evaluation because it directly visualizes the seminal vesicles, ejaculatory ducts, and prostate with superior detail 1, 5.

MRI of the pelvis is reserved for cases where TRUS is negative or inconclusive 1, 4. MRI has excellent soft tissue contrast and can definitively identify seminal vesicle hemorrhage, which appears as blood products within the seminal vesicles 1, 4.

Risk Stratification

• Urologic malignancy is extremely rare with isolated hematospermia (0.05% for prostate cancer, 0.007% for bladder cancer in patients without hematuria or elevated PSA) 6.
• Your age matters: If you are under 40 years, cancer risk is only 0.01%; if over 40 years, risk increases slightly to 0.11% 6.
• Benign hematospermia (no hematuria, normal PSA, normal urinalysis) can be managed conservatively with reassurance 6.

Conservative Management Approach

• Abstain from ejaculation for 2-3 months to allow seminal vesicle hemorrhage to resolve 4.
• Reassurance is appropriate given the benign nature of isolated hematospermia in the absence of other urologic symptoms 4, 6.
• No further testing is needed if this is a single episode or if symptoms resolve with conservative management 6.

Red Flags Requiring Urologic Referral

Immediate urology referral is indicated if you have any of the following 1, 5:

• Persistent or recurrent hematospermia despite conservative management 1
• Associated hematuria (blood in urine) 1, 5
• Elevated PSA above age-adjusted reference ranges 1, 6
• Age >40 years with persistent symptoms 6
• History of urethral stricture, bladder cancer, or prior lower urinary tract surgery 1

Common Pitfalls to Avoid

• Do not assume transabdominal ultrasound can visualize the seminal vesicles adequately—it cannot, which is why TRUS or MRI is needed for persistent cases 1.
• Do not pursue extensive cancer workup for isolated hematospermia in young men (<40 years) without other risk factors, as malignancy risk is negligible (0.01%) 6.
• Do not overlook the need for urinalysis to exclude hematuria, which would change the diagnostic approach entirely 1, 5, 6.