University of Saint-Etienne, GIMAP-EA-3064, Saint Etienne, France.
Parasitology and Mycology, department of Infectious Agents and Hygiene, University Hospital of Saint-Etienne, Saint-Etienne, France.
PLoS Negl Trop Dis. 2021 Jul 6;15(7):e0009515. doi: 10.1371/journal.pntd.0009515. eCollection 2021 Jul.
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.
尿路血吸虫病的诊断基于血清学技术和显微镜检查（ME）的互补性。2015 年至 2019 年期间，我们实验室每年接受的尿路血吸虫病检测数量从 300 例急剧增加到 900 例。因此，我们希望通过比较抗原技术和 PCR 等其他技术来评估尿液显微镜检查（ME，参考和常规技术）的可靠性。为此，我们针对 Schistosoma haematobium（Sh）和 Schistosoma mansoni（Sm）分别优化了两种实时 PCR。
方法/主要发现：对 846 例疑似尿路血吸虫病患者的 914 例尿液样本进行了 PCR 和抗原技术（前 143 例）检测。评估的抗原技术是 Rapid Medical Diagnostics 的 Schisto POC-CCA。将这些结果（抗原技术和 PCR）与所有尿液进行的 ME 进行比较。PCR 技术检测到的 14%（128/914）阳性病例和 ME 检测到的 6.0%（54/914）阳性病例的百分比有显著差异（卡方检验，p<0.001）。这 128 例阳性 PCR 对应于 120 例不同的患者，其中 88.3%（106/120）为年轻移民，11.7%（14/120）为从旅行中返回的法国患者。在这些移民中，超过 75%（80/106）来自说法语的西非。此外，Schisto POC-CCA 的特异性为 39%（46/117），太差而不能在低流行或非流行地区用作筛查工具。
结论/意义：与 ME（参考技术）相比，针对 Sh 和 Sm 的尿液靶向 PCR 是可靠的技术。鉴于我们的结果，我们决定通过直接 ME 始终结合 PCR 技术筛查尿路血吸虫病，该技术显示出更好的可靠性标准。
