PSA is a tumour marker commonly used in diagnosis and treatment of prostate carcinoma. This biomarker is organ-specific but not disease-specific. PSA can be raised in a variety of conditions like urinary tract infections, any instrumentation and prostate carcinoma.
There are very few studies concentrating on correlation of serum PSA with indwelling catheterisation. Rather, it is a commonly held belief that serum PSA is elevated in patients of BPH and patients on indwelling catheter. It is also a well-known fact that patients of BPH can have recurrent urinary tract infections. After excluding patients of urinary tract infection from our study, we observed that serum PSA is not elevated in BPH patients and also non-traumatic urethral catheterisation has no impact on elevation of PSA.
Urethral catheterisation is common procedure performed to treat acute urinary retention. It has been hitherto believed that serum PSA levels are higher in patients on catheter. One study has proposed that prostate biopsy is not necessary in patients with PSA < 10 ng/ml and prostate volume > 60 ml [1]. None of our patients had prostate volume more than 60 ml, and we are of opinion that treatment of patients with raised serum PSA levels should be tailored as per standard protocols, and at no point of time, rise of serum PSA be correlated with catheterisation.
Gazy F et al. [2] observed that indwelling catheter in patients with BPH who underwent urinary retention did cause a significant elevation of serum PSA in those patients having an elevated PSA at baseline and did not change significantly with normal baseline levels. This means elevation of PSA in the absence of urinary tract infection should not be attributed to catheterisation, as we may be missing some underlying serious problem like prostate carcinoma; diagnosis and treatment of which may be delayed. Again, rise in serum PSA should follow standard protocols, as non-traumatic, aseptic catheterisation causes no rise in serum PSA levels. In our study, all patients had baseline serum PSA less than 4 ng/ml. Most of patients in our study had baseline PSA less than 2 ng/ml, thereby excluding patients with other pathologies of prostate which could indirectly influence results of our study by acting as confounder.
Aslan Y et al. [3] in their study concluded that no alteration was found in total and free serum PSA due to in and out urethral catheterisation in patients of BPH, which is consistent with our study.
Serum PSA does not rise after non-traumatic catheterisation and clean intermittent catheterisation (CIC) in patients with neurogenic bladders [4]. Patients with neurogenic bladder were excluded from our study. However, study by Alisgari M does corroborate our findings that urethral catheterisation has no impact on PSA rise.
Torricelli FC [5] observed that although PSA levels were higher in patients with urethral catheterisation than those on cystostomy tube, it was not clinically significant. We did not include any patients with cystostomy in our study. However, findings of our study are in consonance with study by Torricelli F that PSA is not elevated after urethral catheterisation.
Our findings are also in contrast to normally observed PSA in patients of BPH. It is a commonly held belief that about 70% of BPH patients have elevated serum PSA. In our clinical practice, we have observed that many patients with large size prostates have normal PSA and vice versa. This makes us revisit standard dictum that “PSA is organ-specific but not disease-specific.” Our patients under study had maximum prostate volume of 45.26 ml. We tried to eliminate all confounding variables from our study which could independently influence PSA levels. We suggest that as per standard protocols, it is always important to rule out associated urinary tract infection in BPH patients by urine culture. We observed that PSA was not elevated in patients on catheter provided such patients had no urinary tract infection or underlying prostate carcinoma.
