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Table 3 Comparison of sensitivity of the nested multiplex PCR and multiplex PCR methods in real time

From: A novel, nested, multiplex, real-time PCR for detection of bacteria and fungi in blood

Microbe species Order of magnitude [CFU/ml] Detection limit of the multiplex qPCR Order of magnitude [CFU/ml] Detection limit of the nested multiplex qPCR [CFU/ml] *RFU level
  105 104 103 102 101 100 [CFU/ml] 105 104 103 102 101 100   
  + + +   + + + + +   100
A. fumigatus + + 3.7 × 10 3± 2.4 × 10 3 + + + + 3.7 × 10 1± 2.7 × 10 2
(filamentous fungi) + + 3.2 × 103 CFU/reaction + + + + 1.2 CFU/reaction
  + + **CT (31.2-38.5) + + + + CT (29.1-32.2)
  + +   + + + +  
  + + +     + + + +     50
C. albicans + + + + 9.9 × 10 2± 3.4 × 10 3 + + + + + 8.5 × 10 1± 3.6 × 10 2
(yeast) + + + + 9.5 × 101 CFU/reaction + + + + + 0.24 CFU/reaction
  + + +   CT (33.3-37.2) + + + + + CT (29.7-32.1)
  + + +    + + + + +  
  + + +   + + + + + +   100
S. aureus + + + 4.5 × 10 3± 2.5 × 10 3 + + + + + 1.1 × 10 1± 3.7 × 10 2
(Gram positive bacteria) + + + 5.1 × 102 CFU/reaction + + + + + 0.78 CFU/reaction
  + + + CT (34.0-36.7) + + + + + CT (25.2-28.0)
  + +    + + + + +  
  + +     + + + + + +   30
E. coli + + + 5.4 × 10 3± 2.5 × 10 2 + + + + + 1.3 × 10 1± 3.7 × 10 2
(Gram negative bacteria) + + + 6.1 × 102 CFU/reaction + + + + + 0.73 CFU/reaction
  + + + CT (30.5-33.2) + + + + + CT (24.4-27.2)
  + + +   + + + + +  
  1. “+”- the number of positive amplification results conducted in the five repetitions; “” – lack of amplification signal.
  2. *RFU (relative fluorescence unit) signifies the value of the designated baseline.
  3. **CT value, i.e. the consecutive reaction cycle number in which the linear increase of the product cut the established baseline RFU level.