Pattern of urinary bladder sonographic findings in patients evaluated for urinary schistosomiasis

Abstract

Background: Urinary schistosomiasis is one of the neglected tropical diseases. Of the 239 million people with active Schistosoma infections in 2009, 85% lived in sub-Saharan Africa. The urinary bladder is the main site of pathologic damage in patients with urinary schistosomiasis. Objectives: The objectives were to study the prevalence and pattern of sonographic bladder abnormalities in patients evaluated for urinary schistosomiasis. Materials and Methods: All consecutive patients being evaluated for urinary schistosomiasis at the Usmanu Danfodiyo University, Teaching Hospital Sokoto and Federal Medical Centre Birnin Kebbi were prospectively scanned at radiology departments of the two centers. All the patients were scanned with Apogee 800 plus (Japan 2002) and Concept D (Dynamic Imaging Scotland) ultrasound scanners with a variable frequency probes at 3.5–5 MHz. Doppler was used to assess the vascularity of urinary bladder masses, and to differentiate between masses and blood clots which is a diagnostic challenge when using brightness mode (B-mode) sonography alone. The gain was set correctly to allow good visualization of the bladder and adjacent structures. Transverse images are obtained in the true axial plane and angled caudal to show the bladder base. Longitudinal and oblique sagittal images are obtained to complete the examination. All the ultrasound findings and images were recorded as hard copies, and the films were reviewed by a qualified radiologist. The results were analyzed using statistical software SPSS 17.0 for windows. Results: We evaluated a total of 107 patients. The mean age of the patients was 42.9 ± standard deviation 16.8 years, with a range between 7 and 86 years. There were 84 males accounting for 78.5% and 23 females accounting for 21.5%. Abnormal sonographic findings were seen in 101 (94.4%) of patients evaluated. Urinary bladder stone with wall thickening was the most common finding accounting for 37 (36.4%), followed by bladder wall thickening with internal echoes accounting for 32 (21.5%) of the patients. The incidence of irregular bladder mass was 15 (14.0%) while polypoidal mass accounted for 4 (3.7%). Contracted bladder with wall calcification was seen in 7 (6.5%) while no abnormalities were seen in the urinary bladder in 6 (5.6%) of the patients. Conclusion: Abnormal bladder sonographic findings are common in patients evaluated for signs and symptoms of urinary schistosomiasis in North-Western Nigeria, with a prevalence of 94.4% in this current study. Urinary bladder stone with wall thickening followed by bladder wall thickening with internal echoes were the most common findings accounting for 58% of the findings. These sonographic abnormalities should raise the suspicion of urinary schistosomiasis in an endemic region.