Should I routinely measure serum electrolytes and serum creatinine (creatinine) in patients with Benign Prostatic Hyperplasia (BPH)?

Routine Serum Electrolytes and Creatinine Testing in BPH Patients

Routine measurement of serum creatinine and electrolytes is not recommended in the initial evaluation of men with lower urinary tract symptoms (LUTS) secondary to BPH. 1

Evidence-Based Rationale

The American Urological Association (AUA) guidelines clearly state that baseline renal insufficiency appears to be no more common in men with BPH than in men of the same age group in the general population 1. Analysis of several large BPH clinical trial databases with more than 10,000 patient-years of follow-up revealed that renal insufficiency has been reported in well under 1% of patients and is commonly secondary to non-BPH causes such as diabetic nephropathy 1.

In the Medical Therapy of Prostatic Symptoms (MTOPS) trial, only 1.8% of men screened for participation were excluded due to renal or hepatic impairment, with no information available regarding how many of these cases were specifically due to BPH versus other causes 1.

When to Consider Testing

While routine testing is not recommended, there are specific clinical scenarios where measuring serum creatinine and electrolytes may be appropriate:

1. Patients with suspected urinary retention: Those with significant post-void residual volumes
2. Patients with risk factors for renal disease:
   • History of diabetes mellitus 2
   • History of hypertension 2
   • Advanced age with comorbidities 2
3. Patients with abnormal urinalysis: Particularly those with proteinuria or hematuria 1, 3
4. Patients being considered for surgical intervention: As part of preoperative evaluation 1

Conflicting Evidence

It's worth noting that there is some conflicting evidence on this topic:

• A 1997 study found elevated serum creatinine in 11% of men with BPH, with diabetes and hypertension being the strongest predictors 2. The authors concluded they were unable to identify subgroups where the risk was sufficiently low to avoid routine testing.

• A 2001 European Association of Urology guideline recommended creatinine measurement as part of the standard assessment for BPH 4.

• A 2012 review article suggested creatinine measurement should be included in the basic evaluation of patients with BPH 5.

• A recent 2025 study found that people with BPH have a higher long-term risk of chronic kidney disease (HR 1.26), suggesting a potential association between BPH and kidney function deterioration over time 6.

However, the most authoritative and comprehensive guideline from the AUA does not recommend routine measurement 1, and this position is supported by the preoperative testing guidelines which state that electrolyte and renal function testing should be guided by findings from history and physical examination rather than routinely performed 1.

Recommended Diagnostic Approach for BPH

The following tests are recommended for the initial evaluation of men with suspected BPH:

1. Medical history and symptom assessment:

   • Use the AUA Symptom Index or International Prostate Symptom Score (IPSS) 1, 3
   • Assess symptom severity (mild: 0-7, moderate: 8-19, severe: 20-35) 3

2. Physical examination:

   • Digital rectal examination (DRE) to assess prostate size and exclude locally advanced cancer 1, 3

3. Urinalysis:

   • To rule out urinary tract infection and hematuria 1, 3

4. PSA testing (optional):

   • Consider in patients with at least a 10-year life expectancy where knowledge of prostate cancer would change management 1, 3

Conclusion

Based on the most recent and highest quality evidence, routine measurement of serum electrolytes and creatinine is not recommended in the initial evaluation of men with LUTS secondary to BPH. Testing should be reserved for patients with specific risk factors or clinical scenarios that suggest possible renal impairment.