Prospective cohort study using ultrasonography of Schistosoma haematobium–infected migrants

Abstract

Background. Chronic infection with Schistosoma haematobium may lead to serious complications, including bladder carcinoma. Although it is recommended that only bladder masses not regressing within 6 months after praziquantel intake should be investigated invasively, cystoendoscopy is still often performed at diagnosis even in the absence of further signs of concern. No prospective study so far evaluated the evolution of bladder lesions after treatment in case of no risk of reinfection, which could inform case management. Methods. Adult African migrants with active S. haematobium infection, as assessed by positive urine PCR or microscopy for eggs in urine or bladder biopsy, underwent urinary tract ultrasound at enrolment and at 1, 3, 6, 12, and 24 months after praziquantel treatment. Patients in advanced pregnancy or with known Schistosoma-unrelated chronic pathology of the urinary tract were excluded. Results. Twenty-one patients, aged 18-29 years, participated in the study; 10 (47.6%) had bladder masses on ultrasound. Follow-up ≥6 months was completed by 16 (76.2%) patients; ≥12 months by 14 (66.7%), and 24 months by 11 (52.4%). All patients with bladder lesions on enrolment completed a follow-up of ≥6 months. Lesions resolved completely by 6 months in all cases and no new development/re-appearance was observed. Conclusions. This is the first prospective, long-term follow-up study with ultrasound of patients with urinary schistosomiasis outside endemic areas. Mucosal masses in young patients regressed after treatment without recurrence, supporting the recommendation that invasive procedures should be avoided unless lesions or other symptoms/signs of concern persist for > 6 months. Further studies should assess the evolution of bladder lesions after treatment in larger populations, including older age groups, and, ideally, with parallel assessment of other biomarkers of urinary pathology and of residual S. haematobium active infection.

Schistosomiasis screening in non-endemic countries from a cost perspective: Knowledge gaps and research priorities. The case of African long-term residents in a Metropolitan Area, Spain

“…It is also not yet clear how PZQ administration impacts chronic lesions (i.e. eggs-deposit induced fibrosis); according to some reports bladder lesions and fibrosis reverses after therapy, but advanced pathology may persist for a long time in spite of treatment or non-re-exposure [31,32]. A previous study in our area showed an improvement in clinical and analytical abnormalities following treatment of long-term resident migrants [13].…”

Schistosomiasis in non-endemic areas: Italian consensus recommendations for screening, diagnosis and management by the Italian Society of Tropical Medicine and Global Health (SIMET), endorsed by the Committee for the Study of Parasitology of the Italian Association of Clinical Microbiologists (CoSP-AMCLI), the Italian Society of Parasitology (SoIPa), the Italian Society of Gastroenterology and Digestive Endoscopy (SIGE), the Italian Society of Gynaecology and Obstetrics (SIGO), the Italian Society of Colpo

“…The dynamic of bladder lesions after treatment suggests that the lesions usually begin to regress very quickly after PZQ treatment and, therefore, it is reasonable to perform cystoscopy with biopsy only in patients with signs (e.g., haematuria) or bladder lesion which persist > 6 months after treatment [ 109 , 110 ]…”

“…Moreover, cystoscopy with biopsy is recommended in the evaluation of bladder lesions that have features suspected of malignancy and do not regress with antiparasitic therapy after 2–3 months and [ 83 , 109 , 110 ].…”

Schistosomiasis in Europe

“…Those infected are also usually found to suffer from advanced morbidity, indicating that management is often inappropriate in countries of origin, or screening implemented late upon arrival in Europe. For example, a survey [53] found that 47.6% of a group of immigrants to Italy aged 18-29 years infected with S. haematobium had bladder masses at ultrasound examination. Again from Italy, another survey [54] found that a high proportion of patients diagnosed with schistosomiasis, both asymptomatic and symptomatic, were screened or tested only several months after arrival in Italy and most of them presented with clinical apparent disease.…”