Prospective cohort study of the effect of urethral stricture aetiology on the short-term outcomes of patients treated with urethral dilatation at the University Teaching Hospital,Lusaka,Zambia

Abstract

The aetiology of urethral strictures is an important predictor of the course of urethral stricture disease as it influences the choice of treatment of a particular stricture and subsequently affects the outcomes of treatment. In low and middle income countries (LMICs) such as Zambia, which have a high prevalence of urethral strictures, urethroplasty- the golden standard of treatment, is not feasible for all strictures due to the lack of adequate operating theatre facilities. As such, urethral dilatation, a relatively inexpensive procedure that can be performed on an outpatient basis with local anesthesia is the treatment of choice for most patients with urethral strictures at the University Teaching Hospital in Lusaka, Zambia. There is however no clinical evidence that dilatation is the most suitable treatment modality for all types of strictures regardless of etiology. The study aimed to determine the effect that urethral stricture aetiology has on the short term outcome of urethral dilatation. This was a prospective cohort study conducted on patients presenting to the Urology section at the University Teaching Hospital, Lusaka between December 2015 and December 2016. Patients were recruited upon presentation to the urology section. The aetiology of the urethral strictures was elicited from the patient’s medical history and symptoms assessed using a validated symptom score, the International Prostate Symptom Score (IPSS) prior to dilatation. Patients were then followed up for two months after urethral dilatation, and re-evaluated using the same IPSS. The collected data was then analyzed using SPSS Version 23. Other parameters included were patient demographics (age, sex, marital status, education, residence, employment status). A total of 77 patients were recruited in this study. The total participant retention was 90% (n=70). The average age was 42.9. In terms of aetiology, 42.9% (n=30) had a history of self reported sexually transmitted infection; 14.3% (n=10) had a history of previous catheterization; 24.3 % (n=18) had a history of urethral trauma; and 11.4% (n=8) had a history of a urological procedure with urethral involvement, 4.3% (n=3) had no known cause. One patient had a history of both previous catheterization and trauma. Analysis showed a significant association between aetiology and outcomes of dilatation. Post infectious strictures had better outcomes evidenced by a statistically significant improvement in symptoms evidenced by lower IPSS scores post dilatation (p=0.007), those caused by trauma and catheterisation also showed some improvement p=0.032, 0.012 respectively. Post urological procedure strictures showed poor outcomes with no significant improvement of symptoms after dilatation (p=0.180). The aetiology of a stricture affects the outcome of urethral dilatation. Post infectious and post catheterization strictures respond better to dilatation in comparison to other types of strictures in the short term, therefore indications for urethral dilatation should be based on the aetiology of the urethral stricture.