Multiple Cross Displacement Amplification-a more applicable technique in detecting Pseudomonas Aeruginosa of Ventilator-associated Pneumonia ( VAP)
Background: Early and rapid identification of Pseudomonas aeruginosa (P. aeruginosa) in patients with suspected ventilator-associated pneumonia (VAP) provides theoretical clinical advantages in therapeutic optimization strategies.
Methods: The P. aeruginosa-multiple cross displacement amplification (PA-MCDA) assay was conducted at an isothermal temperature during the amplification stage, and products were visually detected by color changes. The entire process was completed within 1 h. A total of 77 strains, including P. aeruginosa species and various other species of non-P. aeruginosa were used to evaluate PA-MCDA assays. Bronchoalveolar lavage fluid (BALF) of suspected VAP patients were examined by the MCDA assay.
Results: The MCDA assay exhibited a 100 percent analytical specificity in detecting PA from all 77 strains, and the limit of detection were as low as 100 fg DNA per reaction. A temperature of 65ºC was recommended as standard during the amplification stage. The agreement between PA-MCDA and bacteria culture was 91.18% (κ= 0.787; p =0.000) in identification of P. aeruginosa in BALF from suspected VAP. The PA-MCDA assay showed values of 92.31%, 90.78%, 77.41% and 97.18% for sensitivity, specificity, positive predictive value and negative predictive value, respectively. PA-MCDA had higher detective rate of P. aeruginosa than bacteria culture in patients with antipseudomonal therapy.
Conclusions: The instrument-free platform of the MCDA assay makes it a simple, rapid and applicable procedure for “on-site” diagnosis and point-of-care testing for the presence of P. aeruginosa without the need for specific bacterial culture.
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Posted 26 May, 2020
On 16 May, 2020
Received 16 May, 2020
Received 16 May, 2020
On 13 May, 2020
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On 13 May, 2020
On 12 May, 2020
On 12 May, 2020
On 13 Apr, 2020
Received 12 Apr, 2020
On 09 Apr, 2020
Received 09 Apr, 2020
Invitations sent on 08 Apr, 2020
On 08 Apr, 2020
On 08 Apr, 2020
On 07 Apr, 2020
On 07 Apr, 2020
On 28 Feb, 2020
On 22 Feb, 2020
Received 22 Feb, 2020
Received 21 Feb, 2020
On 17 Feb, 2020
Invitations sent on 16 Feb, 2020
On 10 Feb, 2020
On 09 Feb, 2020
On 06 Feb, 2020
On 04 Feb, 2020
Multiple Cross Displacement Amplification-a more applicable technique in detecting Pseudomonas Aeruginosa of Ventilator-associated Pneumonia ( VAP)
Posted 26 May, 2020
On 16 May, 2020
Received 16 May, 2020
Received 16 May, 2020
On 13 May, 2020
Invitations sent on 13 May, 2020
On 13 May, 2020
On 12 May, 2020
On 12 May, 2020
On 13 Apr, 2020
Received 12 Apr, 2020
On 09 Apr, 2020
Received 09 Apr, 2020
Invitations sent on 08 Apr, 2020
On 08 Apr, 2020
On 08 Apr, 2020
On 07 Apr, 2020
On 07 Apr, 2020
On 28 Feb, 2020
On 22 Feb, 2020
Received 22 Feb, 2020
Received 21 Feb, 2020
On 17 Feb, 2020
Invitations sent on 16 Feb, 2020
On 10 Feb, 2020
On 09 Feb, 2020
On 06 Feb, 2020
On 04 Feb, 2020
Background: Early and rapid identification of Pseudomonas aeruginosa (P. aeruginosa) in patients with suspected ventilator-associated pneumonia (VAP) provides theoretical clinical advantages in therapeutic optimization strategies.
Methods: The P. aeruginosa-multiple cross displacement amplification (PA-MCDA) assay was conducted at an isothermal temperature during the amplification stage, and products were visually detected by color changes. The entire process was completed within 1 h. A total of 77 strains, including P. aeruginosa species and various other species of non-P. aeruginosa were used to evaluate PA-MCDA assays. Bronchoalveolar lavage fluid (BALF) of suspected VAP patients were examined by the MCDA assay.
Results: The MCDA assay exhibited a 100 percent analytical specificity in detecting PA from all 77 strains, and the limit of detection were as low as 100 fg DNA per reaction. A temperature of 65ºC was recommended as standard during the amplification stage. The agreement between PA-MCDA and bacteria culture was 91.18% (κ= 0.787; p =0.000) in identification of P. aeruginosa in BALF from suspected VAP. The PA-MCDA assay showed values of 92.31%, 90.78%, 77.41% and 97.18% for sensitivity, specificity, positive predictive value and negative predictive value, respectively. PA-MCDA had higher detective rate of P. aeruginosa than bacteria culture in patients with antipseudomonal therapy.
Conclusions: The instrument-free platform of the MCDA assay makes it a simple, rapid and applicable procedure for “on-site” diagnosis and point-of-care testing for the presence of P. aeruginosa without the need for specific bacterial culture.
Figure 1
Figure 2
Figure 3
Figure 4
Figure 5