Molecular approach to the epidemiology of urinary schistosomiasis in France

Abstract

Background The diagnosis of urogenital schistosomiasis is based on the complementarity of serological technique and microscopic examination (ME). Between 2015 and 2019, the number of urinary schistosomiasis tests received in our laboratory increased sharply from 300 to 900 per year. Therefore, we wanted to evaluate the reliability of urine microscopic examination (ME, reference and routine technique) from urine sample by comparing it to other techniques (antigenic technique and PCR). To this end, we optimized two real-time PCRs targeting respectively Schistosoma haematobium (Sh) and Schistosoma mansoni (Sm). Methodology/Principal findings 914 urine samples from 846 patients suspected of urogenital schistosomiasis were prescribed and analyzed by PCR and also by antigenic technique for the first 143 samples. The antigenic technique evaluated was Schisto POC-CCA, Rapid Medical Diagnostics. These results (antigenic technique and PCR) were compared to ME which was performed from all urines. The percentage of 14% (128/914) positive cases with the PCR technique and the percentage of 6.0% (54/914) positive cases with ME is significantly different (Chi 2 test, p<0.001). These 128 positive PCRs correspond to 120 different patients, 88.3% (106/120) of them were young migrants and 11.7% (14/120) were French patients returning from travel. Among these migrants, more than 75% (80/106) came from French-speaking West Africa. In addition, the Schisto POC-CCA showed a specificity of 39% (46/117), too poor to be used as a screening tool in low or non-endemic areas. Conclusion/Significance Targeted Sh and Sm PCRs in urine are reliable techniques compared to ME (reference technique). In view of our results, we decided to screen urinary schistosomiasis by direct ME always coupled by the PCR technique, which has shown better reliability criteria.

Molecular diagnosis of urogenital schistosomiasis in pre-school children, school-aged children and women of reproductive age at community level in central Senegal

“…They have found also less day-today variation of eggs count in urine testing over three days. In another study, the authors have given more details on the correlation between the eggs count and the Ct value [30]. They have found that a single schistosome egg correspond to the Ct-value at 20+/-2.…”

Molecular diagnosis of urogenital schistosomiasis in pre-school children, school-aged children and women of reproductive age at community level in central Senegal

“…They also found less day-to-day variation of egg count in urine testing over 3 days. In another study, the authors gave more details on the correlation between egg count and Ct value [ 30 ]. They found that a single schistosome egg corresponded to the Ct value at 20 ± 2.…”

Foresight in the diagnosis of trematodiasis: innovations versus routine methods

“…Результаты проведенного анализа свидетельствуют о широкой географии проведенных исследований: большая их часть выполнена в эндемичных регионах Юго-Восточной Азии, но также изучение проводилось в странах Европы, США, Африки [12][13][14][15]. Для подтверждения диагноза большинства трематодных инвазий используется микроскопия образцов стула пациента, так как метод является простым и доступным в выполнении, однако, позволяет выявить только инвазию средней и высокой интенсивности [12,16].…”

“…Для подтверждения диагноза большинства трематодных инвазий используется микроскопия образцов стула пациента, так как метод является простым и доступным в выполнении, однако, позволяет выявить только инвазию средней и высокой интенсивности [12,16]. Большей чувствительностью и универсальностью при низкой интенсивности инвазии обладает метод седиментации [15,17,18]. Микроскопия образцов фекалий, мочи или дуоденального содержимого требует обеспечение лаборатории световым микроскопом и квалицированным опытным персоналом, что не всегда возможно в эндемичных очагах трематодозов.…”

“…Довольно много исследований проводится с целью поиска новых мишеней для диагностики и дифференцировки различных инвазий, поисков новых антигенов и их комбинации [10,15,18,24,33,65,[77][78][79][80][81][82][83][84]. В качестве новых маркеров исследуют: сапозин-подобный белок [37], микроРНК, выделенные из экстравезикул сыворотки [85,86], катепсин L3 при шистосомозе [87], очищенный антиген паразита молекулярной массой 27 при фасцилезе [14], межгенный спейсерный участок ДНК F. hepatica [17], антиген шистосомул при инвазии S. mansoni [88].…”