Detrusor ultrastructural studies in human lower urinary tract dysfunction: correlation of structural features and function.

Abstract

Introduction:

Lower urinary tract symptoms (LUTS), voiding dysfunction (VD) and urinary retention are common in the aging population, associated with significant morbidity.(1) LUTS can be due to overactive bladder (OAB), underactive bladder (UAB), bladder outflow obstruction (BOO), or a combination. Diagnosis is key to management, whilst avoiding harm of inappropriate therapy. Due to challenges in evaluation, there may be a role for detrusor ultrastructural analyses in diagnosis and prognosis of VD.(2,3,4)

Objectives:

To investigate detrusor ultrastructural changes in VD in the older population and potential clinical applications. Specifically:

1. females with bladder outflow obstruction (fBOO).

2. males with detrusor underactivity (mDU), with long term functional-structural correlation.

3. older males with coexistent overactive underactive bladders (mCOUB).

Methodology and patient cohort:

Patients were recruited from the Urodynamic Clinic at Concord Hospital. Patients with fBOO, mDU and mCOUB on urodynamic study who were undergoing cystoscopy as part of their clinical management were recruited. Detrusor biopsies were obtained and examined by electron microscopy. Ultrastructural analyses were performed using a standardised protocol and correlated with functional outcomes.

Results

Detrusor ultrastructural features of ‘myohypertrophy’ were similar in fBOO and male BOO; severity correlated with BOO duration and severity. In mDU, severe features of myohyertrophy and degeneration predicted poor long term voiding outcomes. Older mCOUB had concomitant features of myohypertrophy and dysjunctional patterns. Our standardised protocol allowed analyses of all 3 VD.

Conclusions

Detrusor ultrastructural features in patients with fBOO, mDU and mCOUB were described with correlations found between detrusor ultrastructure and lower urinary tract function. Detrusor ultrastructure studies not only improve understanding of VD, but may also assist in diagnosis, prognosis, and management.