Fig. 6. Digital PCR (dPCR) and digital LAMP for rapid pathogen-specific ASTs in clinical samples. (A) AST results analyzed by dPCR. Exposure of susceptible and resistant E. coli isolates to 4 antibiotics. Partitioning bacterial chromosomal DNA into many small volumes enables performing the AST for urinary tract infections in 15 min. (B) Digital LAMP for detecting antibiotic susceptibility by measuring the quantity of a specific AST marker sequence. Urine samples were incubated with or w/o antibiotics (ABX) (steps 1 and 2), AST markers were quantified in the control (−ABX) and treated (+ABX) samples (step 3), and the CT ratios were analyzed (step 4). (C) The theoretical model that predicts the CT ratio as a function of pathogen DNA doubling time and antibiotic exposure time. The operational space gained by using digital counting compared with qPCR is outlined in red. Reproduced from ref. 54 with permission from John Wiley & Sons, Inc., Copyright 2016; and ref. 59 with permission from AAAS, Copyright 2017.