Lower urinary tract symptoms (LUTS) represent a significant healthcare burden worldwide which is predicted to increase given ageing populations. LUTS in men is often associated with Benign Prostatic Hypertrophy (BPH) managed surgically with Transurethral Resection of Prostate (TURP). A number of these patients will have persistent LUTS and require further investigation and treatment. The aim of this study is to identify the aetiology of persistent LUTS by reviewing Urodynamic study (UDS) findings in patients who have had previous TURP.

This was a retrospective cohort study on all patients referred for physician preformed UDS between 2013-2019 in a single centre. Institutional board ethics approval was obtained and patients referred with indication of persistent LUTS with a previous history of TURP were included for further study. Types of TURP procedure included traditional monopolar or bipolar transurethral resection of prostate (tTURP) and greenlight laser photo vaporisation of prostate (GLLPVP). Patients were excluded if there was history of prostatic malignancy, prostatectomy or incomplete data. Data collected included patient demographics, symptoms, cystoscopy and UDS findings. Further subgroup analysis depending on time since TURP was completed (Group A= <2 years Group B= >2years).

There were 1421 consecutive patients referred for VUDS and 106 patients who met inclusion criteria were further analysed. Median age was 73 years (range 45-93) and time interval from TURP to UDS was 45 months (1-312). Majority of patients had previous of tTURP (86%, n=91) and GLLPVP (14%, n=15). There were 64 patients (61%) with mixed voiding symptoms, 31 patients (29%) with only voiding symptoms and 11 patients (10% with only storage symptoms. Overall 104 patients (98%) had aetiology of LUTS diagnosed on UDS. 

On subgroup analysis according to time since TURP, 46 patients (43%) had UDS <2 years since TURP and 60 patients (57%) had UDS >2 years since TURP. UDS findings in group A and B are presented in Table 1. There was no statistical difference in rates of DO (p=0.448) DU (p=0.349) or BOO (p=0.116) on UDS between group A and group B. 

Treatment outcomes of whole study group are outlined in Table 2, in 48 patients (45%) another surgical procedure was recommended. There were 17 patients with neurogenic history (16%) of which majority (65%, n=11) were diagnosed with DO on UDS, neurogenic history was not predictive of having a diagnosis of DO on UDS (p=0.199)

Results of findings according to post void residual (PVR) are presented in Table 3. High PVR was defined as >200mls and patients with high PVR (43%, n=46) were more likely to be diagnosed with DU (74%, 34/46) compared to those with PVR <200mls (p=0.000064). 

Cystoscopy abnormality was noted in 26% patients (n=28) and included urethral strictures (n=15), prostatic regrowth (n=12) and bladder neck contracture (n=1).

The aetiology of LUTS post TURP is multifactorial and complex. Presenting symptoms were mixed voiding and storage in majority of cases. A significant population of patients had DO (44%) and DU (51%) diagnosed on UDS. Those with high PVR were more likely to have DU findings. UDS were able to identify aetiology of persistent LUTS in 98% cases.

This study highlights the potential strength in utility of UDS as diagnostic tool in investigative workup of patients with refractory LUTS post TURP.