Imperial College London
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Professor Alan Fenwick OBE

Faculty of Medicine, School of Public Health

Emeritus Professor
 
 
 
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Contact

 

+44 (0)20 7594 3418a.fenwick Website

 
 
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Location

 

G30Norfolk PlaceSt Mary's Campus

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Summary

 

Publications

Citation

BibTex format

@article{Clements:2018:10.1186/s13071-018-2700-4,
author = {Clements, MN and Corstjens, PLAM and Binder, S and Campbell, CH and de, Dood CJ and Fenwick, A and Harrison, W and Kayugi, D and King, CH and Kornelis, D and Ndayishimiye, O and Ortu, G and Lamine, MS and Zivieri, A and Colley, DG and van, Dam GJ},
doi = {10.1186/s13071-018-2700-4},
journal = {Parasites & Vectors},
title = {Latent class analysis to evaluate performance of point-of-care CCA for low-intensity Schistosoma mansoni infections in Burundi},
url = {http://dx.doi.org/10.1186/s13071-018-2700-4},
volume = {11},
year = {2018}
}
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RIS format (EndNote, RefMan)

TY  - JOUR
AB  - Background:Kato-Katz examination of stool smears is the field-standard method for detecting Schistosoma mansoni infection. However, Kato-Katz misses many active infections, especially of light intensity. Point-of-care circulating cathodic antigen (CCA) is an alternative field diagnostic that is more sensitive than Kato-Katz when intensity is low, but interpretation of CCA-trace results is unclear. To evaluate trace results, we tested urine and stool specimens from 398 pupils from eight schools in Burundi using four approaches: two in Burundi and two in a laboratory in Leiden, the Netherlands. In Burundi, we used Kato-Katz and point-of-care CCA (CCAB). In Leiden, we repeated the CCA (CCAL) and also used Up-Converting Phosphor Circulating Anodic Antigen (CAA).Methods:We applied Bayesian latent class analyses (LCA), first considering CCA traces as negative and then as positive. We used the LCA output to estimate validity of the prevalence estimates of each test in comparison to the population-level infection prevalence and estimated the proportion of trace results that were likely true positives.Results:Kato-Katz yielded the lowest prevalence (6.8%), and CCAB with trace considered positive yielded the highest (53.5%). There were many more trace results recorded by CCA in Burundi (32.4%) than in Leiden (2.3%). Estimated prevalence with CAA was 46.5%. LCA indicated that Kato-Katz had the lowest sensitivity: 15.9% [Bayesian Credible Interval (BCI): 9.2–23.5%] with CCA-trace considered negative and 15.0% with trace as positive (BCI: 9.6–21.4%), implying that Kato-Katz missed approximately 85% of infections. CCAB underestimated disease prevalence when trace was considered negative and overestimated disease prevalence when trace was considered positive, by approximately 12 percentage points each way, and CAA overestimated prevalence in both models. Our results suggest that approximately 52.2% (BCI: 37.8–5.8%) of the CCAB trace readings were true infections.
AU  - Clements,MN
AU  - Corstjens,PLAM
AU  - Binder,S
AU  - Campbell,CH
AU  - de,Dood CJ
AU  - Fenwick,A
AU  - Harrison,W
AU  - Kayugi,D
AU  - King,CH
AU  - Kornelis,D
AU  - Ndayishimiye,O
AU  - Ortu,G
AU  - Lamine,MS
AU  - Zivieri,A
AU  - Colley,DG
AU  - van,Dam GJ
DO  - 10.1186/s13071-018-2700-4
PY  - 2018///
SN  - 1756-3305
TI  - Latent class analysis to evaluate performance of point-of-care CCA for low-intensity Schistosoma mansoni infections in Burundi
T2  - Parasites & Vectors
UR  - http://dx.doi.org/10.1186/s13071-018-2700-4
UR  - http://gateway.webofknowledge.com/gateway/Gateway.cgi?GWVersion=2&SrcApp=PARTNER_APP&SrcAuth=LinksAMR&KeyUT=WOS:000426302700002&DestLinkType=FullRecord&DestApp=ALL_WOS&UsrCustomerID=1ba7043ffcc86c417c072aa74d649202
UR  - http://hdl.handle.net/10044/1/58109
VL  - 11
ER  -
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