First field study using Strong-LAMP for diagnosis of strongyloidiasis in Cubal, Angola.
Angola
Baermann
Cubal
Direct saline microscopy
Field study
Loop-mediated isothermal amplification (LAMP)
Molecular screening
Stool samples
Strong-LAMP
Strongyloidiasis
Journal
Parasites & vectors
ISSN: 1756-3305
Titre abrégé: Parasit Vectors
Pays: England
ID NLM: 101462774
Informations de publication
Date de publication:
31 Oct 2023
31 Oct 2023
Historique:
received:
06
09
2023
accepted:
10
10
2023
medline:
2
11
2023
pubmed:
1
11
2023
entrez:
1
11
2023
Statut:
epublish
Résumé
Strongyloides stercoralis infection is a common neglected tropical disease distributed worldwide, mainly in tropical and subtropical climates. The impact of S. stercoralis infections on human health ranges from mild asymptomatic infections to chronic strongyloidiasis unnoticeable until the host is immunosuppressed. In severe strongyloidiasis, a syndrome of hyperinfection and larval dissemination to various organs can occur with high mortality rates. The diagnosis of strongyloidiasis is challenging because of the absence of a single standard reference test with high sensitivity and specificity, which also makes it difficult to estimate the accuracy of other diagnostic tests. This study aimed to evaluate, for the first time, the use of an easy-to-perform loop-mediated isothermal amplification (LAMP) colorimetric assay (named Strong-LAMP) for the molecular screening of strongyloidiasis in stool samples from patients in a low-resource endemic area in Cubal, Angola. To compare different LAMP application scenarios, the performance of the Strong-LAMP under field conditions in Angola was reassessed in a well-equipped reference laboratory in Spain and compared with a quantitative polymerase chain reaction (qPCR) method. A total of 192 stool samples were collected from adult population in Cubal, Angola, and examined by parasitological methods (direct saline microscopy and Baermann's technique). DNA was extracted from each stool sample using a commercial kit and tested by the colorimetric Strong-LAMP assay for the detection of Strongyloides spp. under field conditions. Furthermore, all samples were shipped to a well-equipped laboratory in Spain, reanalysed by the same procedure and compared with a qPCR method. The overall results after testing were compared. Strongyloides stercoralis larvae were identified by direct saline microscopy and Baermann in a total of 10/192 (5.2%) and 18/192 (9.4%) stool samples, respectively. Other helminth and protozoan species were also identified. The Strong-LAMP-positive results were visually detected in 69/192 (35.9%) stool samples. The comparison of Strong-LAMP results in field conditions and at a reference laboratory matched in a total of 146/192 (76.0%) samples. A total of 24/192 (12.5%) stool samples tested positive by qPCR. This is the first study in which colorimetric Strong-LAMP has been clinically evaluated in a resource-poor strongyloidiasis endemic area. Strong-LAMP has been shown to be more effective in screening for strongyloidiasis than parasitological methods under field conditions and qPCR in the laboratory. Our Strong-LAMP has proven to be a field-friendly and highly accurate molecular test for the diagnosis of strongyloidiasis.
Sections du résumé
BACKGROUND
BACKGROUND
Strongyloides stercoralis infection is a common neglected tropical disease distributed worldwide, mainly in tropical and subtropical climates. The impact of S. stercoralis infections on human health ranges from mild asymptomatic infections to chronic strongyloidiasis unnoticeable until the host is immunosuppressed. In severe strongyloidiasis, a syndrome of hyperinfection and larval dissemination to various organs can occur with high mortality rates. The diagnosis of strongyloidiasis is challenging because of the absence of a single standard reference test with high sensitivity and specificity, which also makes it difficult to estimate the accuracy of other diagnostic tests. This study aimed to evaluate, for the first time, the use of an easy-to-perform loop-mediated isothermal amplification (LAMP) colorimetric assay (named Strong-LAMP) for the molecular screening of strongyloidiasis in stool samples from patients in a low-resource endemic area in Cubal, Angola. To compare different LAMP application scenarios, the performance of the Strong-LAMP under field conditions in Angola was reassessed in a well-equipped reference laboratory in Spain and compared with a quantitative polymerase chain reaction (qPCR) method.
METHODS
METHODS
A total of 192 stool samples were collected from adult population in Cubal, Angola, and examined by parasitological methods (direct saline microscopy and Baermann's technique). DNA was extracted from each stool sample using a commercial kit and tested by the colorimetric Strong-LAMP assay for the detection of Strongyloides spp. under field conditions. Furthermore, all samples were shipped to a well-equipped laboratory in Spain, reanalysed by the same procedure and compared with a qPCR method. The overall results after testing were compared.
RESULTS
RESULTS
Strongyloides stercoralis larvae were identified by direct saline microscopy and Baermann in a total of 10/192 (5.2%) and 18/192 (9.4%) stool samples, respectively. Other helminth and protozoan species were also identified. The Strong-LAMP-positive results were visually detected in 69/192 (35.9%) stool samples. The comparison of Strong-LAMP results in field conditions and at a reference laboratory matched in a total of 146/192 (76.0%) samples. A total of 24/192 (12.5%) stool samples tested positive by qPCR.
CONCLUSIONS
CONCLUSIONS
This is the first study in which colorimetric Strong-LAMP has been clinically evaluated in a resource-poor strongyloidiasis endemic area. Strong-LAMP has been shown to be more effective in screening for strongyloidiasis than parasitological methods under field conditions and qPCR in the laboratory. Our Strong-LAMP has proven to be a field-friendly and highly accurate molecular test for the diagnosis of strongyloidiasis.
Identifiants
pubmed: 37907997
doi: 10.1186/s13071-023-06009-3
pii: 10.1186/s13071-023-06009-3
pmc: PMC10619288
doi:
Types de publication
Journal Article
Langues
eng
Sous-ensembles de citation
IM
Pagination
393Subventions
Organisme : Predoctoral Fellowship Program of Junta de Castilla
ID : 487971
Organisme : Predoctoral Fellowship Program of Junta de Castilla
ID : 422058
Organisme : Instituto de Salud Carlos III
ID : PI22/01721
Informations de copyright
© 2023. The Author(s).
Références
PLoS Negl Trop Dis. 2015 Oct 16;9(10):e0004055
pubmed: 26474169
Trop Med Infect Dis. 2018 May 25;3(2):
pubmed: 30274449
J Appl Microbiol. 2018 Mar;124(3):626-643
pubmed: 29165905
J Clin Microbiol. 2019 Mar 28;57(4):
pubmed: 30728195
Sex Transm Infect. 2006 Dec;82 Suppl 5:v1-6
pubmed: 17151023
PLoS Negl Trop Dis. 2022 Apr 28;16(4):e0010299
pubmed: 35482629
Am J Trop Med Hyg. 2014 Feb;90(2):306-11
pubmed: 24323513
PLoS Negl Trop Dis. 2013;7(1):e2002
pubmed: 23350004
PLoS Negl Trop Dis. 2018 Jan 25;12(1):e0006129
pubmed: 29370166
Biochem Biophys Res Commun. 2001 Nov 23;289(1):150-4
pubmed: 11708792
BMC Infect Dis. 2022 Mar 28;22(1):297
pubmed: 35346087
Appl Microbiol Biotechnol. 2011 Jan;89(2):407-17
pubmed: 20967442
Clin Infect Dis. 2001 Oct 1;33(7):1040-7
pubmed: 11528578
Nucleic Acids Res. 2000 Jun 15;28(12):E63
pubmed: 10871386
Pathogens. 2020 Jun 13;9(6):
pubmed: 32545787
J Clin Microbiol. 2000 Dec;38(12):4463-70
pubmed: 11101581
J Biochem Biophys Methods. 2007 Apr 10;70(3):499-501
pubmed: 17011631
Rev Esp Salud Publica. 2014 Oct;88(5):581-600
pubmed: 25327268
Biosensors (Basel). 2022 Jun 16;12(6):
pubmed: 35735571
PLoS Negl Trop Dis. 2013 Jul 11;7(7):e2288
pubmed: 23875033
Parasit Vectors. 2016 Dec 1;9(1):617
pubmed: 27903301
Cells. 2021 Jul 29;10(8):
pubmed: 34440699
Trans R Soc Trop Med Hyg. 2008 Apr;102(4):314-8
pubmed: 18321548
Int J Mol Sci. 2023 Jan 03;24(1):
pubmed: 36614336
PLoS Negl Trop Dis. 2017 Jan 23;11(1):e0005310
pubmed: 28114314
J Virol Methods. 2008 Aug;151(2):264-270
pubmed: 18524393
Trop Med Int Health. 2018 Sep;23(9):992-1001
pubmed: 29920859
Am J Trop Med Hyg. 2014 Mar;90(3):535-545
pubmed: 24445211
Dis Markers. 2020 May 31;2020:5265198
pubmed: 32566039
Parasit Vectors. 2018 Jan 29;11(1):67
pubmed: 29378626
PLoS Negl Trop Dis. 2016 Jul 14;10(7):e0004836
pubmed: 27415764
Parasitology. 2014 Dec;141(14):1863-72
pubmed: 24780241
PLoS Negl Trop Dis. 2012;6(6):e1572
pubmed: 22745836
Vet Parasitol. 2019 Sep;273:17-23
pubmed: 31442888
PLoS Negl Trop Dis. 2014 Jan 09;8(1):e2640
pubmed: 24427320
Parasitology. 2017 Mar;144(3):263-273
pubmed: 27181117
PLoS Negl Trop Dis. 2020 Aug 10;14(8):e0008505
pubmed: 32776942
Am J Trop Med Hyg. 2017 Oct;97(4):1226-1231
pubmed: 28820707
FEMS Immunol Med Microbiol. 2011 Jun;62(1):41-8
pubmed: 21276085
Nat Protoc. 2008;3(5):877-82
pubmed: 18451795
J Microbiol. 2015 Jan;53(1):1-5
pubmed: 25557475
Curr Infect Dis Rep. 2011 Feb;13(1):35-46
pubmed: 21308453
Trans R Soc Trop Med Hyg. 2009 Apr;103(4):342-6
pubmed: 19195671
PLoS Negl Trop Dis. 2018 Feb 9;12(2):e0006229
pubmed: 29425193
Diagnostics (Basel). 2022 Apr 25;12(5):
pubmed: 35626235
BMC Res Notes. 2008 Aug 28;1:70
pubmed: 18755023
Diagnostics (Basel). 2021 Mar 15;11(3):
pubmed: 33804255
PLoS One. 2018 Feb 14;13(2):e0192637
pubmed: 29444135
J Appl Microbiol. 2012 Nov;113(5):1014-26
pubmed: 22747964
Biomed Res Int. 2020 Nov 15;2020:2868564
pubmed: 33274200
Nat Microbiol. 2019 Jan;4(1):46-54
pubmed: 30546093