Combined rapid susceptibility assay and microorganism identification system

Abstract

In response to the need for highly-sensitive antibiotic susceptibility assays and identification assays that do not require extensive incubation times, the present invention provides automated assay methods and systems that permit the determination of antibiotic susceptibilities and/or microorganism identification in a timeframe that is substantially shorter than has previously been attainable using a hybrid system that combines turbimetric and fluorescence determinations using a single, clear-plastic assay platform. Related devices, kits, and components thereof are also disclosed.

1 - 60 . (canceled)  
     
     
         61 . An apparatus for microorganism identification (ID) and antimicrobial susceptibility testing (AST) comprising: 
 receiving means for receiving specimen-containing hybrid panels;    transporting means for transporting said specimen-containing hybrid panels through the apparatus;    incubating means for incubating said specimen-containing hybrid panels at a temperature such that microorganism growth occurs;    light generating means to provide sources of light for measuring reaction results in said specimen-containing hybrid panels;    detecting means for detecting light output for measuring reaction results in said specimen-containing hybrid panels; and    analyzing means for interpreting said detected light into ID or AST results; and    wherein said ID determination is complete by approximately 2.5 hours and said AST determination is complete by approximately 22 hours.    
     
     
         62 . The apparatus of  claim 61  wherein said analyzing means is programmed with instructions for determining minimum inhibitory concentration (MIC) of antimicrobials for AST comprising the algorithm of  FIG. 1 .  
     
     
         63 . The apparatus of  claim 61  wherein said analyzing means is programmed with instructions for determining MIC of antimicrobials for AST comprising: 
 a. set read times for turbidity;    b. set thresholds for well growth;    c. at first read time determine if the MIC control well has growth;    d. if the answer to (c) is yes, record turbidity and return plate to incubation;    e. if the answer to (c) is no, return plate to incubation;    f. at second read time determine if the MIC control well has growth;    g. if answer to (f) is yes, record turbidity and if the second turbidity reading from said MIC control well is higher than the first turbidity reading from said MIC control well and reached a first threshold for well growth, then record MIC control well as growth;    h. if the answer to (f) is no, return plate to incubation;    i. repeat steps (f) and (h) until maximum read time is reached;    j. if the answer to (g) is growth, read MIC test well to determine if growth;    k. if the answer to (j) is yes, record turbidity and determine ratio of turbidity of antibiotic well to turbidity of growth well;    l. if ratio of step (k) exceeds a threshold ratio level, isolate may become resistant and return plate to incubation;    m. if ratio of step (k) is less than said threshold ratio level, final MIC value is reported; and    n. when maximum read time is reached, record turbidity and report results.    
     
     
         64 . The apparatus of  claim 61  wherein said light generating means independently generates fluorescent light and non-fluorescent light.  
     
     
         65 . The apparatus of  claim 61  wherein said detecting means can detect fluorescent signals.  
     
     
         66 . The apparatus of  claim 61  wherein said detecting means can detect turbidity signals.  
     
     
         67 . An apparatus for high throughput microorganism identification (ID) and antimicrobial susceptibility testing (AST) comprising: 
 a. receiving means for receiving a plurality of specimen-containing hybrid panels,    b. transporting means for transporting said plurality of specimen-containing hybrid panels through the apparatus;    c. incubating means for incubating said plurality of specimen-containing hybrid panels at a temperature such that microorganism growth occurs;    d. light generating means to provide sources of light for measuring reaction results in said plurality of specimen-containing hybrid panels;    e. detecting means for detecting light output for measuring reaction results in said plurality of specimen-containing hybrid panels; and    f. analyzing means for interpreting said detected light into ID or AST results; and    g. wherein said ID determination is complete by approximately 2.5 hours and said AST determination is complete by approximately 22 hours.    
     
     
         68 . The apparatus of  claim 67  wherein said analyzing means is programmed with instructions for determining MIC of antimicrobials for AST comprising the algorithm of  FIG. 1 .  
     
     
         69 . A method for accurate and rapid antimicrobial susceptibility testing comprising: 
 a. preparing a sample to be tested;    b. inoculating a panel having a plurality of wells with said sample, wherein said panel comprises a plastic microtiter plate having wells for rapidly determining said microorganism's susceptibility to at least one antimicrobial agent;    c. placing said inoculated panel into an apparatus that maintains said inoculated panels at a predetermined temperature for a predetermined time;    d. incubating said inoculated panel in said apparatus at said predetermined temperature for a first predetermined time;    e. reading said wells for determining said microorganism's susceptibility at at least one second predetermined time by transmitting a visible light source through said wells for determining said microorganism's susceptibility to at least one antimicrobial agent, collecting said resulting visible light signals and converting said visible light signals into a turbidity reading;    f. analyzing said turbidity reading according to the algorithm of  FIG. 1 ;    g. repeating steps d-f until the result fulfils the criteria of the algorithm.    h. determining said susceptibility to at least one antimicrobial agent; and    i. retaining said antimicrobial susceptibility such that said antimicrobial sensitivity can be rapidly reported.    
     
     
         70 . The method of  claim 69  wherein said analyzing step (f) comprises: 
 a. set read times for turbidity;    b. set thresholds for well growth;    c. at first read time determine if the MIC control well has growth;    d. if the answer to (c) is yes, record turbidity and return plate to incubation;    e. if the answer to (c) is no, return plate to incubation;    f. at second read time determine if the MIC control well has growth;    g. if answer to (f) is yes, record turbidity and if the second turbidity reading from said MIC control well is higher than the first turbidity reading from said MIC control well and reached a first threshold for well growth, then record MIC control well as growth;    h. if the answer to (f) is no, return plate to incubation;    i. repeat steps (f) and (h) until maximum read time is reached;    j. if the answer to (g) is growth, read MIC test well to determine if growth;    k. if the answer to (j) is yes, record turbidity and determine ratio of turbidity of antibiotic well to turbidity of growth well;    l. if ratio of step (k) exceeds a threshold ratio level, isolate may become resistant and return plate to incubation;    m. if ratio of step (k) is less than said threshold ratio level, final MIC value is reported; and    n. when maximum read time is reached, record turbidity and report results.    
     
     
         71 . An apparatus for the rapid and accurate determination of microorganism identification (ID) and antimicrobial susceptibility testing (AST), said apparatus comprising: 
 receiving means for receiving specimen-containing hybrid panels;    transporting means for transporting said specimen-containing hybrid panels through the apparatus;    incubating means for incubating said specimen-containing hybrid panels at a temperature such that microorganism growth occurs;    light generating means to provide sources of light for measuring reaction results in said specimen-containing hybrid panels;    detecting means for detecting light output for measuring reaction results in said specimen-containing hybrid panels; and    analyzing means for interpreting said detected light into ID or AST results; and    wherein said ID determination is complete by approximately 2.5 hours and said AST determination is complete by approximately 22 hours.    
     
     
         72 . The apparatus of  claim 71  wherein said analyzing means is programmed with instructions for determining minimum inhibitory concentration (MIC) of antimicrobials for AST comprising the algorithm of  FIG. 1 .