TY - JOUR
T1 - A proof-of-principle study for the point-of-care detection of ESBL (CTX-M) by NG-Test
® CTX-M MULTI lateral flow assay in urine samples using a simplified method for use in a resource-limited setting.
AU - Nurjadi, Dennis
AU - Chalin, Arnaud
AU - Hauswaldt, Susanne
AU - Olson, Linus
AU - Larsson, Mattias
AU - Östholm, Åse
AU - Velavan, Thirumalaisamy P
AU - Boutin, Sébastien
AU - Rupp, Jan
AU - Nilsson, Lennart E
AU - Hanberger, Håkan
N1 - © The Author(s) 2024. Published by Oxford University Press on behalf of British Society for Antimicrobial Chemotherapy.
PY - 2024/8
Y1 - 2024/8
N2 - BACKGROUND: The rise of extended-spectrum β-lactamase-producing Enterobacterales (ESBL-E) in low- and middle-income countries limits treatment options, leading to the frequent use of broad-spectrum antibiotics. Reducing time-to-result for a urinary infection can facilitate correct antibiotic treatment and support antimicrobial and diagnostic stewardship measures. This study compared two simplified enrichment methods for detecting CTX-M directly from urine specimens.METHODS: Two enrichment methods, namely centrifugation of 2 mL urine and filtration of 1 mL urine using the DirecTool adaptor, were compared using 20 culture-positive urine samples (20 suspected ESBL-E and 20 non-ESBL-E). CTX-M production was detected using a lateral flow assay (LFA), NG-Test
® CTX-MMULTI. The presence of
bla
CTX-M genes was confirmed by whole-genome sequencing (WGS).
RESULTS: The results of both enrichment methods were identical, with a sensitivity of 87.5% and a specificity of 100%. In 19/20 (95%) of the urine samples, the results of the CTX-M LFA were identical with the phenotypic confirmation and WGS. Both methods could detect ESBL-E bacteriuria with ≥10
4 cfu/mL. All ESBL-E-negative samples were identified accurately. Both enrichment methods yielded negative results in one ESBL-E-positive (CTX-M-15) sample despite phenotypic and genotypic confirmation of ESBL production. High leukocyte count (>500 cells/µL), the presence of boric acid or polymicrobial samples did not appear to impact the performance of both enrichment methods.
CONCLUSIONS: Our study underscores the feasibility of directly detecting CTX-M in urine. Simplified enrichment methods, particularly with a filtration kit, enhance the assay's practicality, rendering it suitable for use in primary care, emergency departments or remote laboratories without sophisticated equipment.
AB - BACKGROUND: The rise of extended-spectrum β-lactamase-producing Enterobacterales (ESBL-E) in low- and middle-income countries limits treatment options, leading to the frequent use of broad-spectrum antibiotics. Reducing time-to-result for a urinary infection can facilitate correct antibiotic treatment and support antimicrobial and diagnostic stewardship measures. This study compared two simplified enrichment methods for detecting CTX-M directly from urine specimens.METHODS: Two enrichment methods, namely centrifugation of 2 mL urine and filtration of 1 mL urine using the DirecTool adaptor, were compared using 20 culture-positive urine samples (20 suspected ESBL-E and 20 non-ESBL-E). CTX-M production was detected using a lateral flow assay (LFA), NG-Test
® CTX-MMULTI. The presence of
bla
CTX-M genes was confirmed by whole-genome sequencing (WGS).
RESULTS: The results of both enrichment methods were identical, with a sensitivity of 87.5% and a specificity of 100%. In 19/20 (95%) of the urine samples, the results of the CTX-M LFA were identical with the phenotypic confirmation and WGS. Both methods could detect ESBL-E bacteriuria with ≥10
4 cfu/mL. All ESBL-E-negative samples were identified accurately. Both enrichment methods yielded negative results in one ESBL-E-positive (CTX-M-15) sample despite phenotypic and genotypic confirmation of ESBL production. High leukocyte count (>500 cells/µL), the presence of boric acid or polymicrobial samples did not appear to impact the performance of both enrichment methods.
CONCLUSIONS: Our study underscores the feasibility of directly detecting CTX-M in urine. Simplified enrichment methods, particularly with a filtration kit, enhance the assay's practicality, rendering it suitable for use in primary care, emergency departments or remote laboratories without sophisticated equipment.
UR - http://www.scopus.com/inward/record.url?scp=85198032701&partnerID=8YFLogxK
UR - https://www.mendeley.com/catalogue/6cd7d32f-de03-310c-9537-3d9e98544d8d/
U2 - 10.1093/jacamr/dlae103
DO - 10.1093/jacamr/dlae103
M3 - Journal articles
C2 - 38966331
SN - 2632-1823
VL - 6
SP - dlae103
JO - JAC-antimicrobial resistance
JF - JAC-antimicrobial resistance
IS - 4
M1 - dlae103
ER -
