Introduction: Recurrent urinary tract infections (RUTI) have a negative impact on quality of life and generate high costs for public health. Although long-term antibiotic therapy continues to be the mainstay of RUTI treatment, it is often ineffective due to progressive antibacterial resistance. In selected women, electrofulguration (EF) of chronic trigonitis (CT) lesions has shown to reduce UTI episodes. The diagnosis of CT is usually made through cystoscopy. However, this is an invasive and expensive procedure. In this scenario, a highly accurate non-invasive preoperative diagnostic method is necessary. The objective of this study is to determine the efficacy of transvaginal bladder ultrasound (TBU) for CT diagnosis in women when compared to cystoscopy.
Methods: Between August 2010 and December 2021, 83 women with RUTI defined as three or more episodes of UTI per year were included in the study. All had failed multiple antibiotic courses. Besides proper evaluation to exclude common causes of RUTI, all patients had undergone a pre-operative TBU with a partially full bladder (urinary volume around 200mL). This partial filling facilitates the analysis of the trigone mucosa lining (continuous or irregular) and thickness (=2mm or >3mm) and allows for the assessment of urine debris. All underwent cystoscopy with biopsy for diagnostic confirmation at the time of trigone cauterization.
Results: The median age was 64 years (range 17 to 76). The procedure was well tolerated by all patients. Trigonitis lesions could be easily detected by TBU in 100% of patients when compared to cystoscopy. TBU identifies chronic trigonitis through the following findings: (a) thickening of trigone mucosa above 3 mm; (b) irregular and interrupted mucosa lining; (c) mucosa shadding and tissue flaps; (d) increased trigonal blood flow on Doppler; (e) presence of free debris floating in the urine. On the contrary, the normal-looking trigone is ultrasonographically regular, uniform, revealing a continuous and uninterrupted thin lining (= 2mm).
Conclusions: The diagnostic agreement index between ultrasound and cystoscopy was 100%. TBU proved to be an efficient, practical, cheap and fast method for minimally invasive diagnosis of trigonitis in women. To our knowledge, this is the first report that proposes the use of transvaginal ultrasound as an alternative method for diagnosing trigonitis.