- Email: [email protected]
A promising new test to detect Streptococcus pneumoniae urinary antigen
+Model MEDMAL-3891; No. of Pages 4
ARTICLE IN PRESS Disponible en ligne sur
ScienceDirect www.sciencedirect.com Médecine et maladies infectieuses xxx (2017) xxx–xxx
Short communication
A promising new test to detect Streptococcus pneumoniae urinary antigen Un nouveau test prometteur pour la détection de l’antigénurie Streptococcus pneumoniae C. Loïez ∗ , C. Duployez , F. Wallet ∗ Service de bactériologie-hygiène, centre de biologie-pathologie, CHU de Lille, 59000 Lille, France Received 8 March 2017; accepted 20 July 2017
Abstract Background. – Streptococcus pneumoniae is the main etiology of community-acquired pneumonia (CAP). A quick detection of urinary antigen helps in obtaining a documented result in case of Streptococcus pneumoniae CAP. ® ® Methods. – We compared the BinaxNOW S. pneumoniae test with the new urinary antigen Sofia S. pneumoniae FIA. We examined 133 urine samples. ® ® Results. – Of the 133 included and tested non-concentrated urine samples, BinaxNOW and Sofia tests yielded 122 and 113 negative results and 11 and 20 positive results, respectively. The overall agreement between the tests was good. ® Conclusion. – This new test enabled the diagnosis of seven additional cases (7/133 = 5.2%). The improved detection with Sofia may be due ® ® to the immunofluorescence method used by this new test as compared with the colorimetric method used by BinaxNOW . Sofia also offers the advantage of being connected to the laboratory information system (LIS) allowing an automated traceability. © 2017 Elsevier Masson SAS. All rights reserved. ®
®
Keywords: BinaxNOW ; Sofia ; Streptococcus pneumoniae
Résumé Introduction. – Streptococcus pneumoniae est la principale bactérie en cause dans les pneumonies communautaires. Des tests rapides immunoenzymatiques détectant l’antigène de S. pneumoniae dans les urines facilitent le diagnostic étiologique de ces pneumonies. ® ® Méthodes. – Nous avons comparé le nouveau test Sofia S. pneumoniae FIA avec le test le plus ancien et le plus fréquemment utilisé : BinaxNOW S. pneumoniae. ® ® Résultats. – Parmi les 133 échantillons, le test BinaxNOW et le test Sofia sont négatifs dans 122 et 113 cas, et positifs dans 11 et 20 cas, respectivement. Le coefficient de concordance est bon. ® Conclusion. – Ce nouveau test a permis de diagnostiquer sept cas supplémentaires (7/133 = 5,2 %). Le test Sofia utilise une nouvelle technologie ® ® basée sur l’immunofluorescence à la différence du test colorimétrique BinaxNOW , expliquant probablement les meilleurs résultats du test Sofia . ® Enfin, le test Sofia est connectable au système informatique, permettant une trac¸abilité automatisée pour l’accréditation. © 2017 Elsevier Masson SAS. Tous droits r´eserv´es. ®
®
Mots clés : BinaxNOW ; Streptococcus pneumoniae ; Sofia
∗
Corresponding authors at: Laboratoire de bactériologie, institut de microbiologie, centre de biologie pathologie, 59037 Lille cedex, France. E-mail addresses: [email protected] (C. Loïez), [email protected] (C. Duployez), [email protected] (F. Wallet).
http://dx.doi.org/10.1016/j.medmal.2017.07.007 0399-077X/© 2017 Elsevier Masson SAS. All rights reserved.
Please cite this article in press as: Loïez C, et al. A promising new test to detect Streptococcus pneumoniae urinary antigen. Med Mal Infect (2017), http://dx.doi.org/10.1016/j.medmal.2017.07.007
+Model
ARTICLE IN PRESS
MEDMAL-3891; No. of Pages 4 2
C. Loïez et al. / Médecine et maladies infectieuses xxx (2017) xxx–xxx
1. Introduction
3. Results
Streptococcus pneumoniae is the main etiology of community-acquired pneumonia (CAP). Although conventional microbiological cultures of blood, pleural fluids, or sputum may document CAP, in more than 50% of cases the causative agent is not detected because of prior administration of antibiotics. A quick detection of urinary antigen helps in obtaining a documented result in case of Streptococcus pneumoniae CAP [1]. Urinary antigen test options used to be limited to immunochromatographic assays: the oldest leading reagent proposed by ® manufactured diagnosis companies is the BinaxNOW S. pneumoniae antigen test (Alere, Jouy-en-Josas, France) [2]. Our aim ® was to compare the BinaxNOW S. pneumoniae test with the ® new urinary antigen Sofia S. pneumoniae FIA (Quidel, San Diego, CA, USA) using a novel immunofluorescence technology coupled with an automatic analyzer allowing for laboratory information system (LIS) connectivity, data storage, quality control management and multiple user security features.
Among the 133 included and tested non-concentrated urine ® ® samples (Table 1), BinaxNOW S. pneumoniae and Sofia S. pneumoniae FIA tests yielded 122 and 113 negative results and 11 and 20 positive results, respectively (Table 2). A total of nine discrepant results were observed (positive when tested with ® ® Sofia assay but negative with the BinaxNOW method). Out of these nine results, two samples turned positive when retested ® with BinaxNOW after concentration. The overall agreement between the tests was moderate ( = 0.67; CI 0.51–0.83) and good ( = 0.76; CI 0.60–0.92) before and after concentration, respectively [3]. Seven case patients (patients 2, 3, 5, 11, 12, 13 and 17) remained discordant. Out of the seven case patients with discordant results, five (patients 2, 3, 5, 11, 12) were consistent with S. pneumoniae CAP after careful consideration of the medical file (various suggestive clinical features and an infiltrate observed on chest radiography or other imaging technique and/or microbiological data such as positive blood cultures). The CAP diagnosis of two patients (patients 13 and 17) only depended on the urine antigen result.
2. Materials and methods 4. Discussion A total of 133 urine samples were analyzed with both S. pneumoniae antigen tests. Samples were collected from adult patients presenting with a feverish respiratory syndrome within 48 hours after hospitalization. The tests were performed as per manufacturers’ recommendations in non-concentrated urine samples. In ® case of a positive result with the Sofia S. pneumoniae FIA test ® and a negative result with the BinaxNOW S. pneumoniae test, the urine sample was concentrated by filtration and retested with ® BinaxNOW test; thus increasing the sensitivity of this test.
This new test enabled the diagnosis of seven additional cases (7/133 = 5.2%) compared with our routine antigen urinary ® test. The improved detection with Sofia may be due to the immunofluorescence method of this new test as compared ® with the colorimetric method of the BinaxNOW test for the qualitative detection of S. pneumoniae antigen in urine ® samples. Sofia also offers the advantage of being connected to the LIS allowing an automated traceability as required by the
Table 1 ® ® Comparison of results of the Sofia S. pneumoniae FIA assay and the BinaxNOW S. pneumoniae assay. ® ® Comparaison des résultats des antigénuries réalisées à l’aide du test Sofia versus BinaxNOW . ®
BinaxNOW
On non-concentrated urine
®
Sofia
+ −
On concentrated urine
+
−
+
−
11 0
9 113
13 0
7 113
Please cite this article in press as: Loïez C, et al. A promising new test to detect Streptococcus pneumoniae urinary antigen. Med Mal Infect (2017), http://dx.doi.org/10.1016/j.medmal.2017.07.007
+Model
ARTICLE IN PRESS
MEDMAL-3891; No. of Pages 4
C. Loïez et al. / Médecine et maladies infectieuses xxx (2017) xxx–xxx
3
Table 2 Biological, microbiological and radiological characteristics of the 20 positive patients (discordant cases in bold). Caractéristiques biologiques, microbiologiques et radiologiques des 20 patients positifs (cas discordants en gras). Patient
Age (years)
®
Sofia result
®
BinaxNOW result
Nonconcentrated
Concentrated
Chest radiography and/or computed tomography
S. pneumoniae detected in blood culture
S. pneumoniae detected in respiratory tract specimen culture
White blood cell count (cells/mm3 )
Right lower lobar consolidation Right lower lobar consolidation Left lower lobar consolidation Lower lobar consolidation Lower lobar consolidation Bilateral lobar consolidation Right lower lobar consolidation Not performed
No
13.68
48
12.32
237
8.23
323
14.54
54
20.08
373
Yes
Not performed Not performed Not performed Not performed Not performed Yes
3.24
124
No
No
8.07
208
Yes
No
8.12
317
Left pleural effusion Normal
No
No
12.36
62
No
No
7.35
326
No
Not performed No
16.72
213
8.88
119
Not performed Not performed Yes
7.78
116
20.16
345
14.98
124
5.34
159
67.55
278
15.62
327
8.72
121
2.17
286
1
48
Positive
Positive
2
74
Positive
Negative
Not performed Negative
3
80
Positive
Negative
Negative
4
86
Positive
Positive
5
29
Positive
Negative
Not performed Negative
6
64
Positive
Positive
7
73
Positive
Positive
8
47
Positive
Positive
9
62
Positive
Negative
10
68
Positive
Positive
11
62
Positive
Negative
Not performed Negative
12
55
Positive
Negative
Negative
13
51
Positive
Negative
Negative
Right lower lobar consolidation Bilateral lobar consolidation Not performed
14
92
Positive
Positive
15
78
Positive
Positive
47
Positive
Positive
17
90
Positive
Negative
Right lower lobar consolidation Bilateral lobar consolidation Bilateral lobar consolidation Normal
Not performed No
16
Not performed Not performed Not performed Negative
18
62
Positive
Negative
Positive
Yes
19
84
Positive
Positive
20
58
Positive
Positive
Not performed Not performed
Left lower lobar consolidation Right lower lobar consolidation Bilateral pleural effusion and bilateral lobar consolidation
Not performed Not performed Not performed Positive
Not performed No No No
No No
No
No
Not performed Not performed Not performed No
No
No
No
C-reactive protein (mg/L) Normal range < 3
accreditation rules. Nevertheless, further studies using a larger cohort of urine samples are required to confirm the performance of this new S. pneumoniae urinary antigen test.
Disclosure of interest
Contribution of authors
Acknowledgments
C. Loiez and F. Wallet gathered the urinary samples, analyzed the data and wrote the article. C. Duployed contributed to reviewing and approving the article.
Sofia S. pneumoniae FIA kits and equipment were kindly provided by Quidel Corp. We would like to thank the technicians of our laboratory and specially Helmut Artelpik for performing the antigen urinary tests.
The authors declare that they have no competing interest.
®
Please cite this article in press as: Loïez C, et al. A promising new test to detect Streptococcus pneumoniae urinary antigen. Med Mal Infect (2017), http://dx.doi.org/10.1016/j.medmal.2017.07.007
+Model MEDMAL-3891; No. of Pages 4 4
ARTICLE IN PRESS C. Loïez et al. / Médecine et maladies infectieuses xxx (2017) xxx–xxx
References [1] Vernet G, Saha S, Satzke C, Burgess DH, Alderson M, Maisonneuve JF, et al. Laboratory-based diagnosis of pneumococcal pneumonia: state of the art and unmet needs. Clin Microbiol Infect 2011;3:1–13.
[2] Dominguez J, Gali N, Blanco S, Pedroso P, Prat C, Matas L, et al. Detection of Streptococcus pneumoniae antigen by a rapid immunochromatographic assay in urine samples. Chest 2001;119:243–9. [3] Landis JR, Koch GG. The measurement of observer agreement for categorical data. Biometrics 1977;33:159–74.
Please cite this article in press as: Loïez C, et al. A promising new test to detect Streptococcus pneumoniae urinary antigen. Med Mal Infect (2017), http://dx.doi.org/10.1016/j.medmal.2017.07.007
ARTICLE IN PRESS Disponible en ligne sur
ScienceDirect www.sciencedirect.com Médecine et maladies infectieuses xxx (2017) xxx–xxx
Short communication
A promising new test to detect Streptococcus pneumoniae urinary antigen Un nouveau test prometteur pour la détection de l’antigénurie Streptococcus pneumoniae C. Loïez ∗ , C. Duployez , F. Wallet ∗ Service de bactériologie-hygiène, centre de biologie-pathologie, CHU de Lille, 59000 Lille, France Received 8 March 2017; accepted 20 July 2017
Abstract Background. – Streptococcus pneumoniae is the main etiology of community-acquired pneumonia (CAP). A quick detection of urinary antigen helps in obtaining a documented result in case of Streptococcus pneumoniae CAP. ® ® Methods. – We compared the BinaxNOW S. pneumoniae test with the new urinary antigen Sofia S. pneumoniae FIA. We examined 133 urine samples. ® ® Results. – Of the 133 included and tested non-concentrated urine samples, BinaxNOW and Sofia tests yielded 122 and 113 negative results and 11 and 20 positive results, respectively. The overall agreement between the tests was good. ® Conclusion. – This new test enabled the diagnosis of seven additional cases (7/133 = 5.2%). The improved detection with Sofia may be due ® ® to the immunofluorescence method used by this new test as compared with the colorimetric method used by BinaxNOW . Sofia also offers the advantage of being connected to the laboratory information system (LIS) allowing an automated traceability. © 2017 Elsevier Masson SAS. All rights reserved. ®
®
Keywords: BinaxNOW ; Sofia ; Streptococcus pneumoniae
Résumé Introduction. – Streptococcus pneumoniae est la principale bactérie en cause dans les pneumonies communautaires. Des tests rapides immunoenzymatiques détectant l’antigène de S. pneumoniae dans les urines facilitent le diagnostic étiologique de ces pneumonies. ® ® Méthodes. – Nous avons comparé le nouveau test Sofia S. pneumoniae FIA avec le test le plus ancien et le plus fréquemment utilisé : BinaxNOW S. pneumoniae. ® ® Résultats. – Parmi les 133 échantillons, le test BinaxNOW et le test Sofia sont négatifs dans 122 et 113 cas, et positifs dans 11 et 20 cas, respectivement. Le coefficient de concordance est bon. ® Conclusion. – Ce nouveau test a permis de diagnostiquer sept cas supplémentaires (7/133 = 5,2 %). Le test Sofia utilise une nouvelle technologie ® ® basée sur l’immunofluorescence à la différence du test colorimétrique BinaxNOW , expliquant probablement les meilleurs résultats du test Sofia . ® Enfin, le test Sofia est connectable au système informatique, permettant une trac¸abilité automatisée pour l’accréditation. © 2017 Elsevier Masson SAS. Tous droits r´eserv´es. ®
®
Mots clés : BinaxNOW ; Streptococcus pneumoniae ; Sofia
∗
Corresponding authors at: Laboratoire de bactériologie, institut de microbiologie, centre de biologie pathologie, 59037 Lille cedex, France. E-mail addresses: [email protected] (C. Loïez), [email protected] (C. Duployez), [email protected] (F. Wallet).
http://dx.doi.org/10.1016/j.medmal.2017.07.007 0399-077X/© 2017 Elsevier Masson SAS. All rights reserved.
Please cite this article in press as: Loïez C, et al. A promising new test to detect Streptococcus pneumoniae urinary antigen. Med Mal Infect (2017), http://dx.doi.org/10.1016/j.medmal.2017.07.007
+Model
ARTICLE IN PRESS
MEDMAL-3891; No. of Pages 4 2
C. Loïez et al. / Médecine et maladies infectieuses xxx (2017) xxx–xxx
1. Introduction
3. Results
Streptococcus pneumoniae is the main etiology of community-acquired pneumonia (CAP). Although conventional microbiological cultures of blood, pleural fluids, or sputum may document CAP, in more than 50% of cases the causative agent is not detected because of prior administration of antibiotics. A quick detection of urinary antigen helps in obtaining a documented result in case of Streptococcus pneumoniae CAP [1]. Urinary antigen test options used to be limited to immunochromatographic assays: the oldest leading reagent proposed by ® manufactured diagnosis companies is the BinaxNOW S. pneumoniae antigen test (Alere, Jouy-en-Josas, France) [2]. Our aim ® was to compare the BinaxNOW S. pneumoniae test with the ® new urinary antigen Sofia S. pneumoniae FIA (Quidel, San Diego, CA, USA) using a novel immunofluorescence technology coupled with an automatic analyzer allowing for laboratory information system (LIS) connectivity, data storage, quality control management and multiple user security features.
Among the 133 included and tested non-concentrated urine ® ® samples (Table 1), BinaxNOW S. pneumoniae and Sofia S. pneumoniae FIA tests yielded 122 and 113 negative results and 11 and 20 positive results, respectively (Table 2). A total of nine discrepant results were observed (positive when tested with ® ® Sofia assay but negative with the BinaxNOW method). Out of these nine results, two samples turned positive when retested ® with BinaxNOW after concentration. The overall agreement between the tests was moderate ( = 0.67; CI 0.51–0.83) and good ( = 0.76; CI 0.60–0.92) before and after concentration, respectively [3]. Seven case patients (patients 2, 3, 5, 11, 12, 13 and 17) remained discordant. Out of the seven case patients with discordant results, five (patients 2, 3, 5, 11, 12) were consistent with S. pneumoniae CAP after careful consideration of the medical file (various suggestive clinical features and an infiltrate observed on chest radiography or other imaging technique and/or microbiological data such as positive blood cultures). The CAP diagnosis of two patients (patients 13 and 17) only depended on the urine antigen result.
2. Materials and methods 4. Discussion A total of 133 urine samples were analyzed with both S. pneumoniae antigen tests. Samples were collected from adult patients presenting with a feverish respiratory syndrome within 48 hours after hospitalization. The tests were performed as per manufacturers’ recommendations in non-concentrated urine samples. In ® case of a positive result with the Sofia S. pneumoniae FIA test ® and a negative result with the BinaxNOW S. pneumoniae test, the urine sample was concentrated by filtration and retested with ® BinaxNOW test; thus increasing the sensitivity of this test.
This new test enabled the diagnosis of seven additional cases (7/133 = 5.2%) compared with our routine antigen urinary ® test. The improved detection with Sofia may be due to the immunofluorescence method of this new test as compared ® with the colorimetric method of the BinaxNOW test for the qualitative detection of S. pneumoniae antigen in urine ® samples. Sofia also offers the advantage of being connected to the LIS allowing an automated traceability as required by the
Table 1 ® ® Comparison of results of the Sofia S. pneumoniae FIA assay and the BinaxNOW S. pneumoniae assay. ® ® Comparaison des résultats des antigénuries réalisées à l’aide du test Sofia versus BinaxNOW . ®
BinaxNOW
On non-concentrated urine
®
Sofia
+ −
On concentrated urine
+
−
+
−
11 0
9 113
13 0
7 113
Please cite this article in press as: Loïez C, et al. A promising new test to detect Streptococcus pneumoniae urinary antigen. Med Mal Infect (2017), http://dx.doi.org/10.1016/j.medmal.2017.07.007
+Model
ARTICLE IN PRESS
MEDMAL-3891; No. of Pages 4
C. Loïez et al. / Médecine et maladies infectieuses xxx (2017) xxx–xxx
3
Table 2 Biological, microbiological and radiological characteristics of the 20 positive patients (discordant cases in bold). Caractéristiques biologiques, microbiologiques et radiologiques des 20 patients positifs (cas discordants en gras). Patient
Age (years)
®
Sofia result
®
BinaxNOW result
Nonconcentrated
Concentrated
Chest radiography and/or computed tomography
S. pneumoniae detected in blood culture
S. pneumoniae detected in respiratory tract specimen culture
White blood cell count (cells/mm3 )
Right lower lobar consolidation Right lower lobar consolidation Left lower lobar consolidation Lower lobar consolidation Lower lobar consolidation Bilateral lobar consolidation Right lower lobar consolidation Not performed
No
13.68
48
12.32
237
8.23
323
14.54
54
20.08
373
Yes
Not performed Not performed Not performed Not performed Not performed Yes
3.24
124
No
No
8.07
208
Yes
No
8.12
317
Left pleural effusion Normal
No
No
12.36
62
No
No
7.35
326
No
Not performed No
16.72
213
8.88
119
Not performed Not performed Yes
7.78
116
20.16
345
14.98
124
5.34
159
67.55
278
15.62
327
8.72
121
2.17
286
1
48
Positive
Positive
2
74
Positive
Negative
Not performed Negative
3
80
Positive
Negative
Negative
4
86
Positive
Positive
5
29
Positive
Negative
Not performed Negative
6
64
Positive
Positive
7
73
Positive
Positive
8
47
Positive
Positive
9
62
Positive
Negative
10
68
Positive
Positive
11
62
Positive
Negative
Not performed Negative
12
55
Positive
Negative
Negative
13
51
Positive
Negative
Negative
Right lower lobar consolidation Bilateral lobar consolidation Not performed
14
92
Positive
Positive
15
78
Positive
Positive
47
Positive
Positive
17
90
Positive
Negative
Right lower lobar consolidation Bilateral lobar consolidation Bilateral lobar consolidation Normal
Not performed No
16
Not performed Not performed Not performed Negative
18
62
Positive
Negative
Positive
Yes
19
84
Positive
Positive
20
58
Positive
Positive
Not performed Not performed
Left lower lobar consolidation Right lower lobar consolidation Bilateral pleural effusion and bilateral lobar consolidation
Not performed Not performed Not performed Positive
Not performed No No No
No No
No
No
Not performed Not performed Not performed No
No
No
No
C-reactive protein (mg/L) Normal range < 3
accreditation rules. Nevertheless, further studies using a larger cohort of urine samples are required to confirm the performance of this new S. pneumoniae urinary antigen test.
Disclosure of interest
Contribution of authors
Acknowledgments
C. Loiez and F. Wallet gathered the urinary samples, analyzed the data and wrote the article. C. Duployed contributed to reviewing and approving the article.
Sofia S. pneumoniae FIA kits and equipment were kindly provided by Quidel Corp. We would like to thank the technicians of our laboratory and specially Helmut Artelpik for performing the antigen urinary tests.
The authors declare that they have no competing interest.
®
Please cite this article in press as: Loïez C, et al. A promising new test to detect Streptococcus pneumoniae urinary antigen. Med Mal Infect (2017), http://dx.doi.org/10.1016/j.medmal.2017.07.007
+Model MEDMAL-3891; No. of Pages 4 4
ARTICLE IN PRESS C. Loïez et al. / Médecine et maladies infectieuses xxx (2017) xxx–xxx
References [1] Vernet G, Saha S, Satzke C, Burgess DH, Alderson M, Maisonneuve JF, et al. Laboratory-based diagnosis of pneumococcal pneumonia: state of the art and unmet needs. Clin Microbiol Infect 2011;3:1–13.
[2] Dominguez J, Gali N, Blanco S, Pedroso P, Prat C, Matas L, et al. Detection of Streptococcus pneumoniae antigen by a rapid immunochromatographic assay in urine samples. Chest 2001;119:243–9. [3] Landis JR, Koch GG. The measurement of observer agreement for categorical data. Biometrics 1977;33:159–74.
Please cite this article in press as: Loïez C, et al. A promising new test to detect Streptococcus pneumoniae urinary antigen. Med Mal Infect (2017), http://dx.doi.org/10.1016/j.medmal.2017.07.007