Squamous metaplasia as a manifestation of urogenital schistosomiasis and its complications

Abstract

Background. Leukoplakia or squamous metaplasia (SM) of the bladder detect with the endoscopic diagnostic with urothelial biopsy. The reason for the development of SM, besides irritation of a mucous membrane by chemical reagents or drugs, is prolonged exposure of schistosome eggs (Schistosoma haematobium), penetrating into the bladder during invasion. The most common cause of urothelial SM is urogenital schistosomiasis (US) and one of the most known and dangerous its complications is schistosomiasis bladder cancer (sBC). Features of cellular mechanisms linking the schistosomes invasion with the development of sBC are not well studied. Urothelial SM use to indicate by the presence of cancerous transformation, or may be a marker of long-term inflammation. The flow of squamous cell carcinoma of the bladder usually is accompanied by a keratinizing SM. Taking into account the socio-political conditions of the modern world and the development of tourism, the relevance of the diagnosis and treatment of patients with those diseases continues to grow. Materials and methods . The results of observation the group of 181 residents of the Republic of Angola with gross haematuria analyzed from 2009 till 2010. US verified in all cases. We conducted urine tests for detection of schistosomes, cytological examination of urine sediment (CEUS), ultrasound and endoscopic diagnostic methods, biopsy of the urothelium. The database of the hospitals used in the statistical analysis. Results. In 142 (78.5 %) cases uncomplicated US confirmed, at 39 (21.5 %) patients sBC revealed. Schistosomes invasion and trichomonas were combined in 21 (14.8 %) cases. Changes and thickness of the bladder wall by ultrasound were accompanied with the SM in 26.8 % cases. The combination of SM and hydronephrosis caused by ureteral stenosis due to US were founded in 2 (1.4 %) cases. The coincidence cases of PM with ultrasound picture, featuring for manifestations US did not exceed 14.1 %. Cystoscopically SM detected at 76 (53.5 %) patients. The SM confirmed by complex of CEUS, cystoscopy and ultrasound in cases of gross granulomatous mucosal changes of the bladder wall with a significant (> 8 mm) thickening of the body wall. SM verified in 25 (64.1 %) cases with sBC (median age 29.25 years). The incidence of metaplasia was directly correlated with the stage of cancer. All patients with US and sBC were treated with praziquantel 40 mg / kg and, additionally, with fluoroquinolones in non-specific bacteriuria cases (28.9 %) and with antiprotozoa’s in cases of trichomoniasis (14.8 %). Control cystoscopy performed 10 days after the end of treatment. After the course of conservative therapy all symptoms of SM disappeared, without need to specialized surgical treatment. Conclusion. Identifying SM in patients with sBC does not have independent clinical significance: it was founded in conjunction with other specific mucosal changes, may accompany the uncomplicated forms of US and was not detected in patients with sBC in early stages. Therefore we are not being able to use that change as specific marker of the cancer transformation. The complete regression of dysplastic urothelium changes verified at the end of conservative treatment. Further study of the structure and changes of the bladder epithelium in patients with US is very important for understand the pathogenesis of tumor growth and for keeping a high quality of life for young patients with firstly revealed bladder cancer of parasitic nature.