To differentiate between a urethral stricture and other causes of urinary obstruction in a patient, a thorough clinical assessment and targeted investigations are essential.
History and Symptoms: Urethral stricture often presents with a history of a slow, weak urinary stream, spraying of urine, and sometimes recurrent urinary tract infections or retention. Other causes of obstruction, such as benign prostatic enlargement (BPE), may present with similar lower urinary tract symptoms (LUTS) but typically have a different clinical context and progression.
Physical Examination: Examination should include inspection of the external genitalia and digital rectal examination to assess the prostate and exclude other causes like prostate enlargement or malignancy.
Specialist Assessment and Investigations: Men with complicated or bothersome LUTS should be referred for specialist assessment where uroflowmetry (flow rate measurement) and post-void residual volume measurement can be performed to assess the degree and nature of obstruction.
Cystoscopy: This is a key diagnostic tool and should be offered when clinically indicated, such as in cases of recurrent infection, haematuria, or profound symptoms. Cystoscopy allows direct visualization of the urethra and bladder, enabling identification of strictures, their location, and severity, distinguishing them from other causes of obstruction.
Imaging: Imaging of the upper urinary tract is not routinely recommended at initial assessment unless complications or suspicion of other pathology exist.
In summary, differentiation relies on clinical history, physical examination, and specialist investigations including uroflowmetry and cystoscopy to directly visualize the urethra and identify strictures versus other obstructive causes such as BPE or neurological dysfunction NICE CG97,NICE CG148.