Skip to main page content
U.S. flag

An official website of the United States government

Dot gov

The .gov means it’s official.
Federal government websites often end in .gov or .mil. Before sharing sensitive information, make sure you’re on a federal government site.

Https

The site is secure.
The https:// ensures that you are connecting to the official website and that any information you provide is encrypted and transmitted securely.

Access keys NCBI Homepage MyNCBI Homepage Main Content Main Navigation
. 2025 May 30;18(1):196.
doi: 10.1186/s13071-025-06832-w.

Evaluation of molecular and serological testing for imported urogenital schistosomiasis screening in a referral tropical medicine centre in Barcelona, Spain

Patricia Martínez-Vallejo  1   2 , Alejandro Mediavilla  1   2 , Aroa Silgado  1   3 , Francesc Zarzuela  4 , Lidia Goterris  1 , Carles Rubio Maturana  1   2 , Nuria Serre-Delcor  2   3   4 , Inés Oliveira-Souto  3   4 , Fernando Salvador  3   4 , Joan Joseph-Munne  1 , María Luisa Aznar  3   4 , Diana Pou  3   4 , Begoña Treviño  3   4 , Israel Molina  3   4 , Javier Sotillo  5 , Elena Sulleiro  6   7
Affiliations

Evaluation of molecular and serological testing for imported urogenital schistosomiasis screening in a referral tropical medicine centre in Barcelona, Spain

Patricia Martínez-Vallejo et al. Parasit Vectors. .

Abstract

Background: Schistosomiasis, a major neglected tropical disease, is caused by Schistosoma spp. It is estimated that more than 200 million people are affected worldwide, mostly in Africa. The gold standard diagnosis of urogenital schistosomiasis (UGS) is the microscopic visualisation of Schistosoma haematobium eggs in concentrated urine; however, its sensitivity is low. This study aimed to evaluate the effectiveness of molecular and serological testing for imported UGS screening in asymptomatic sub-Saharan migrants in a non-endemic setting.

Methods: A retrospective cross-sectional study between November 2021 and December 2022 was conducted by collecting demographic, clinical and laboratory data from the medical records of migrants from endemic areas screened for UGS at the International Health Unit Vall d'Hebron-Drassanes, Barcelona, Spain. Urine samples were analysed by real-time PCR for S. haematobium DNA and by microscopy for egg detection. Serum samples were tested using a serological assay based on enzyme-linked immunosorbent assay (ELISA). UGS was confirmed by a positive result in real-time PCR and/or microscopy, while possible UGS was defined as a case with only a positive serological result.

Results: A total of 604 patients were included in this study; 32 out of 604 (5.3%) urine samples were positive for S. haematobium by real-time PCR and/or microscopy examination (confirmed UGS cases). Schistosoma haematobium DNA was detected in 28/604 (4.6%) urine samples, while eggs were visualised in 24/604 (3.9%), with 12 discordant cases between both techniques. Real-time PCR demonstrated a sensitivity of 83.3%, a specificity of 98.6%, and a kappa value of 0.76. Serology was performed in 529/604 cases and exhibited lower specificity, 70.87% (kappa value 0.26). Other laboratory parameters such as leukocyturia, microhaematuria, eosinophilia and elevated IgE were significantly associated with UGS diagnosis.

Conclusions: Real-time PCR proved to be more sensitive than microscopy for diagnosing imported UGS in non-endemic settings, with minimal discordance between methods. The serological test exhibited very low specificity and high sensitivity rates, suggesting its usefulness as a screening test among high-risk populations in non-endemic settings.

Keywords: Schistosoma haematobium; Molecular diagnostics; Real-time PCR; Serological diagnosis; Urine; Urogenital schistosomiasis.

PubMed Disclaimer

Conflict of interest statement

Declarations. Ethics approval and consent to participate: The study protocol PR(AG)514/2023 was approved by the Ethical Review Board of the Vall d’Hebron University Hospital (Barcelona, Spain). Procedures were performed following the ethical standards laid down in the Declaration of Helsinki as revised in 2000. The need for informed consent was waived because of the study’s design and all data were anonymized before being analysed. Consent for publication: Not applicable. Competing interests: The authors declare no competing interests.

Figures

Fig. 1
Fig. 1
Flowchart of the study design detailing the methodological sequence of urine sample collection and analysis by conventional microscopy, real-time PCR and serology. UGS: urogenital schistosomiasis
See this image and copyright information in PMC

References

    1. World Health Organization. Schistosomiasis. https://www.who.int/news-room/fact-sheets/detail/schistosomiasis Accessed 06 Sep 2024.
    1. Roure S, López F, Oliva I, Pérez-Quílez O, March O, Chamorro A, et al. 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. PLoS Negl Trop Dis. 2023;17:1–18. 10.1371/journal.pntd.0011221. - PMC - PubMed
    1. Salas-Coronas J, Pérez Pérez A, Roure S, Sánchez Peinador C, Santos Larrégola L, Arranz Izquierdo J, et al. Documento de consenso para el manejo de la esquistosomiasis en atención primaria [Consensus document for the management of schistosomiasis in Primary Care]. Atención Primaria. 2022;54:102408. 10.1016/j.aprim.2022.102408. - PMC - PubMed
    1. Gryseels B, Polman K, Clerinx J, Kestens L. Human schistosomiasis. Lancet. 2006;368:1106–18. 10.1016/S0140-6736(06)69440-3. - PubMed
    1. Lo NC, Bezerra FSM, Colley DG, Fleming FM, Homeida M, Kabatereine N, et al. Review of 2022 WHO guidelines on the control and elimination of schistosomiasis. Lancet Infect Dis. 2022;22:e327–35. 10.1016/S1473-3099(22)00221-3. - PubMed

MeSH terms

LinkOut - more resources