Browsing by Author "Joris Menten"

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A global comparative evaluation of commercial immunochromatographic rapid diagnostic tests for visceral leishmaniasis
(Oxford University Press, 2012) Jane Cunningham; Epco Hasker; Pradeep Das; Sayda El Safi; Hiro Goto; Dinesh Mondal; Margaret Mbuchi; Maowia Mukhtar; Ana Rabello; Suman Rijal; Shyam Sundar; Monique Wasunna; Emily Adams; Joris Menten; Rosanna Peeling; Marleen Boelaert; Murari Das; Edward Oliveira; Tália Machado de Assis; Khondaker Rifathassan Bhaskar; M. Mamun Huda; Mukidul Hassan; Asim Osman Abdoun; Aymen Awad; Mohamed Osman; Dinesh Kumar Prajapati; Kamlesh Gidwani; Puja Tiwary; Anamaria Mello Miranda Paniago; Maria Carmen Arroyo Sanchez; Beatriz Julieta Celeste; Diane Jacquet; Charles Magiri; A. Muia; J. Kesusu; Al Farazdag Ageed; Nuha Galal; Osman Salih Osman; A.K. Gupta; Afrad S. Bimal; V.N.R. Das
Background. Poor access to diagnosis stymies control of visceral leishmaniasis (VL). Antibody-detecting rapid diagnostic tests (RDTs) can be performed in peripheral health settings. However, there are many brands available and published reports of variable accuracy. Methods. Commercial VL RDTs containing bound rK39 or rKE16 antigen were evaluated using archived human sera from confirmed VL cases (n = 750) and endemic non-VL controls (n = 754) in the Indian subcontinent (ISC), Brazil, and East Africa to assess sensitivity and specificity with 95 confidence intervals. A subset of RDTs were also evaluated after 60 days' heat incubation (37°C, 45°C). Interlot and interobserver variability was assessed. Results. All test brands performed well against ISC panels (sensitivity range, 92.8-100; specificity range, 96-100); however, sensitivity was lower against Brazil and East African panels (61.5-91 and 36.8-87.2, respectively). Specificity was consistently > 95 in Brazil and ranged between 90.8 and 98 in East Africa. Performance of some products was adversely affected by high temperatures. Agreement between lots and readers was good to excellent ( > 0.73-0.99). Conclusions. Diagnostic accuracy of VL RDTs varies between the major endemic regions. Many tests performed well and showed good heat stability in the ISC; however, reduced sensitivity against Brazilian and East African panels suggests that in these regions, used alone, several RDTs are inadequate for excluding a VL diagnosis. More research is needed to assess ease of use and to compare performance using whole blood instead of serum and in patients coinfected with human immunodeficiency virus. © 2012 The Author.
Arsenic Exposure and Outcomes of Antimonial Treatment in Visceral Leishmaniasis Patients in Bihar, India: A Retrospective Cohort Study
(Public Library of Science, 2015) Meghan R. Perry; Vijay K. Prajapati; Joris Menten; Andrea Raab; Joerg Feldmann; Dipankar Chakraborti; Shyam Sundar; Alan H. Fairlamb; Marleen Boelaert; Albert Picado
In the late twentieth century, emergence of high rates of treatment failure with antimonial compounds (SSG) for visceral leishmaniasis (VL) caused a public health crisis in Bihar, India. We hypothesize that exposure to arsenic through drinking contaminated groundwater may be associated with SSG treatment failure due to the development of antimony-resistant parasites.A retrospective cohort design was employed, as antimony treatment is no longer in routine use. The study was performed on patients treated with SSG between 2006 and 2010. Outcomes of treatment were assessed through a field questionnaire and treatment failure used as a proxy for parasite resistance. Arsenic exposure was quantified through analysis of 5 water samples from within and surrounding the patient’s home. A logistic regression model was used to evaluate the association between arsenic exposure and treatment failure. In a secondary analysis survival curves and Cox regression models were applied to assess the risk of mortality in VL patients exposed to arsenic. One hundred and ten VL patients treated with SSG were analysed. The failure rate with SSG was 59%. Patients with high mean local arsenic level had a non-statistically significant higher risk of treatment failure (OR = 1.78, 95% CI: 0.7–4.6, p = 0.23) than patients using wells with arsenic concentration <10 μg/L. Twenty one patients died in our cohort, 16 directly as a result of VL. Arsenic levels ≥ 10 μg/L increased the risk of all-cause (HR 3.27; 95% CI: 1.4–8.1) and VL related (HR 2.65; 95% CI: 0.96–7.65) deaths. This was time dependent: 3 months post VL symptom development, elevated risks of all-cause mortality (HR 8.56; 95% CI: 2.5–29.1) and of VL related mortality (HR 9.27; 95% CI: 1.8–49.0) were detected. This study indicates a trend towards increased treatment failure in arsenic exposed patients. The limitations of the retrospective study design may have masked a strong association between arsenic exposure and selection for antimonial resistance in the field. The unanticipated strong correlation between arsenic exposure and VL mortality warrants further investigation. © 2015 Perry et al.
Clinical Research on Neglected Tropical Diseases: Challenges and Solutions
(Public Library of Science, 2016) Marleen Boelaert; The NIDIAG Consortium; Barbara Barbé; Emmanuel Bottieau; Christophe Burm; Philippe Büscher; Jozefien Buyze; Stijn Deborggraeve; Koen De Winne; Philippe Gillet; David Hendrickx; Arabella Huys; Jan Jacobs; Veerle Lejon; Filip Meheus; Joris Menten; Evelien Paessens; Katja Polman; Raffaella Ravinetto; Stijn Rogé; Céline Schurmans; Achilleas Tsoumanis; Johan Van Griensven; Harry van Loen; Kristien Verdonck; Cédric Yansouni; François Chappuis; Emilie Alirol; Ninon S. Horié; Suman Rijal; Nisha K. Bhatta; Narayan R. Bhattarai; Prahlad Karki; Basudha Khanal; Kanika Koirala; Bickram Pradhan; Surendra Uranw; Jürg Utzinger; Sören L. Becker; Martin W. Bratschi; Justin K. Chatigre; Jean T. Coulibaly; Jean-Paul Gohou; Mathias Herrmann; Stefanie Knopp; Hanspeter Marti; Eliézer K. N’Goran; Beatrice Nickel; Pierre H.H. Schneeberger; Kigbafori D. Silué; Peter Steinmann; Lutz von Müller; Penelope Vounatsou; Joel A. Yao; Patrick K. Yao; Peiling Yap; Pascal Lutumba; Claude Basilua; Edmonde Bonebe; Gustave Bukasa; Sebastien Inamba; Jean Roger Kalo Lilo; Vincent Kambale; Tharcisse Kayembe; Octavie Lunguya; Maria Mashako; Luigi Mininkulu; Alain Mpanya; Deby Mukendi; Dieudonné Mumba; Jean-Jacques Muyembe; Pati Pyan; Sayda El-Safi; Mannar Abdel-Rahman; Saad Ageed Al farazdag; Atia Atia; Abdallah Bashir; Ahmed Bashir; Mohammed Bashir; Mohamedelfateh Eljack; Alhabib Elhabib; Husam Elshikh; Awad Hammad; Mohammed Issa; Mohamed S. Mohamed; Mohammed O. Mohammedali; Salah Mohammed Ali; Modether Morsal; Shawgi Hago Almugadam; Lim Kruy; P. Maling Ellen; Leng Long; Manoza Maricel; Saman Ratanakneary; Bouy Sok; Sok Sopheak; Ros Sreyphors; Teav Syna; Sopheak Thai; Phe Thong; So Veasna; Che Yanith; Michael Miles; Tapan Bhattacharyya; Sakib Burza; Graham Clark; Andrew Falconar; Tegwen Marlais; Adelaide Michaels; Rosanna Peeling; Matthew Yeo; Shyam Sundar; Shahnawaj Alam; Jaya Chakravarty; Poonam Kumari; Madhukar Rai; Deepak K. Verma; Pascal Mertens; Stéphane Degallaix; Laurence Denorme; Quentin Gilleman; Thierry Leclipteux; Thomas Simon; Caroline Thunissen; Moussa Sacko; Cheik O. Coulibaly; Birama D. Diakité; Mama N. Doumbia; Aly Landouré; Rénion Saye; Mamadou S. Traoré; Hassan K.M. Fofana; Yodi Mahendradhata; Riris A. Ahmad; Bintari Dwihardiani; Norma S. Hurif; Rizqiani A. Kusumasari; Fransiska Meyanti; Elsa H. Murhandarwati; Haripurnomo Kushadiwijaya; Trisasi Lestari; Irene M. Rahakbauw; Ratih Restiani; Supargiyono; Henry Surendra; Mohamad Syairaji; Jarir A. Thobari
[No abstract available]
Comparative evaluation of freeze-dried and liquid antigens in the direct agglutination test for serodiagnosis of visceral leishmaniasis (ITMA-DAT/VL)
(2006) Diane Jacquet; Marleen Boelaert; Jill Seaman; Suman Rijal; Shyam Sundar; Joris Menten; Eddy Magnus
Objective: The direct agglutination test (DAT) for visceral leishmaniasis (VL) with liquid (LQ) antigen is known to be only moderately reproducible because of inter-observer and batch-to-batch variability as well as its sensitivity to temperature and shaking during transport. We evaluated a DAT with freeze-dried (FD) antigen and compared it with the LQ antigen version. Methods: Blood samples of clinical VL suspects and healthy endemic controls were collected in Sudan, Nepal and India. Both test versions were performed in duplicate in the respective countries and in the reference laboratory. Interbatch variability and stability tests were conducted and agreement was examined within and between centres on a dichotomic scale by Cohen's kappa as well as on a continuous scale through Bland-Altman plots. Results: The FD antigen remains fully active even after storage at 45°C for 24 months. Using a cut-off titre of 1 : 6400, the agreement between the FD and the LQ formats was excellent. Conclusion: The major advantages of FD antigen are its better stability at higher temperatures and its longer shelf life, which make it much more suitable than the LQ version for use in the field. © 2006 Blackwell Publishing Ltd.
Determinants for progression from asymptomatic infection to symptomatic visceral leishmaniasis: A cohort study
(Public Library of Science, 2018) Jaya Chakravarty; Epco Hasker; Sangeeta Kansal; Om Prakash Singh; Paritosh Malaviya; Abhishek Kumar Singh; Ankita Chourasia; Toolika Singh; Medhavi Sudarshan; Akhil Pratap Singh; Bhawana Singh; Rudra Pratap Singh; Bart Ostyn; Michaela Fakiola; Albert Picado; Joris Menten; Jenefer M. Blackwell; Mary E. Wilson; David Sacks; Marleen Boelaert; Shyam Sundar
Background: Asymptomatic Leishmania donovani infections outnumber clinical presentations, however the predictors for development of active disease are not well known. We aimed to identify serological, immunological and genetic markers for progression from L. donovani infection to clinical Visceral Leishmaniasis (VL). Methods: We enrolled all residents >2 years of age in 27 VL endemic villages in Bihar (India). Blood samples collected on filter paper on two occasions 6–12 months apart, were tested for antibodies against L. donovani with rK39-ELISA and DAT. Sero converters, (negative for both tests in the first round but positive on either of the two during the second round) and controls (negative on both tests on both occasions) were followed for three years. At the start of follow-up venous blood was collected for the following tests: DAT, rK39- ELISA, Quantiferon assay, SNP/HLA genotyping and L.donovani specific quantitative PCR. Results: Among 1,606 subjects enrolled,17 (8/476 seroconverters and 9/1,130 controls) developed VL (OR 3.1; 95% CI 1.1–8.3). High DAT and rK39 ELISA antibody titers as well as positive qPCR were strongly and significantly associated with progression from seroconversion to VL with odds ratios of 19.1, 30.3 and 20.9 respectively. Most VL cases arose early (median 5 months) during follow-up. Conclusion: We confirmed the strong association between high DAT and/or rK39 titers and progression to disease among asymptomatic subjects and identified qPCR as an additional predictor. Low predictive values do not warrant prophylactic treatment but as most progressed to VL early during follow-up, careful oberservation of these subjects for at least 6 months is indicated. © 2018, Public Library of Science. All rights reserved. https://creativecommons.org/publicdomain/zero/1.0/.
Latent Infection with Leishmania donovani in Highly Endemic Villages in Bihar, India
(Public Library of Science, 2013) Epco Hasker; Sangeeta Kansal; Paritosh Malaviya; Kamlesh Gidwani; Albert Picado; Rudra Pratap Singh; Ankita Chourasia; Abhishek Kumar Singh; Ravi Shankar; Joris Menten; Mary Elizabeth Wilson; Marleen Boelaert; Shyam Sundar
Introduction: Asymptomatic persons infected with the parasites causing visceral leishmaniasis (VL) usually outnumber clinically apparent cases by a ratio of 4-10 to 1. We describe patterns of markers of Leishmania donovani infection and clinical VL in relation to age in Bihar, India. Methods: We selected eleven villages highly endemic for Leishmania donovani. During a 1-year interval we conducted two house to house surveys during which we collected blood samples on filter paper from all consenting individuals aged 2 years and above. Samples were tested for anti-leishmania serology by Direct Agglutination Test (DAT) and rK39 ELISA. Data collected during the surveys included information on episodes of clinical VL among study participants. Results: We enrolled 13,163 persons; 6.2% were reactive to DAT and 5.9% to rK39. Agreement between the tests was weak (kappa = 0.30). Among those who were negative on both tests at baseline, 3.6% had converted to sero-positive on either of the two tests one year later. Proportions of sero-positives and sero-converters increased steadily with age. Clinical VL occurred mainly among children and young adults (median age 19 years). Discussion: Although infection with L. donovani is assumed to be permanent, serological markers revert to negative. Most VL cases occur at younger ages, yet we observed a steady increase with age in the frequency of sero-positivity and sero-conversion. Our findings can be explained by a boosting effect upon repeated exposure to the parasite or by intermittent release of parasites in infected subjects from safe target cells. A certain proportion of sero-negative subjects could have been infected but below the threshold of antibody abundance for our serologic testing.
Long-lasting Insecticidal Nets to Prevent Visceral Leishmaniasis in the Indian Subcontinent; Methodological Lessons Learned from a Cluster Randomised Controlled Trial
(Public Library of Science, 2015) Albert Picado; Bart Ostyn; Suman Rijal; Shyam Sundar; Shri Prakash Singh; François Chappuis; Murari Lal Das; Basudha Khanal; Kamlesh Gidwani; Epco Hasker; Jean Claude Dujardin; Veerle Vanlerberghe; Joris Menten; Marc Coosemans; Marleen Boelaert
[No abstract available]
Serological markers for Leishmania donovani infection in Nepal: Agreement between direct agglutination test and rK39 ELISA
(2010) Basudha Khanal; Suman Rijal; Bart Ostyn; Albert Picado; Kamlesh Gidwani; Joris Menten; Diane Jacquet; Veerle Lejon; François Chappuis; Marleen Boelaert
Visceral leishmaniasis (VL) is an important vector-borne disease caused by Leishmania donovani in the Indian subcontinent. The actual incidence and role of asymptomatic infections in the region are not well known. We used the direct agglutination test (DAT) and the rK39 ELISA as L. donovani infection markers in 10 VL endemic villages in Nepal. DAT titre distribution showed two subgroups in the population (infected and non-infected individuals), while rK39 did not. The agreement between both tests was moderate (κ=0.53; 95% CI 0.49-0.57). More research is needed to develop validated markers for Leishmania infection. © 2010 Blackwell Publishing Ltd.