Device, system and method for determining a fibrinogen level in a blood sample

Abstract

The present invention relates to device for determining a fibrinogen level in a sample comprising, a first input for obtaining an attenuance signal over time indicative of a fibrin polymerization of said sample, a second input for obtaining a reactant concentration signal over time indicative of a reactant concentration in said sample, wherein the reactant is any substance leading to the cleavage of fibrinogen to fibrin, a simulation unit running a model using the reactant concentration signal as an input to provide a simulated attenuance signal over time, and an evaluation unit configured to infer the fibrinogen level of said sample by comparing the attenuance signal over time with the simulated attenuance signal over time.

1 . Device for determining a fibrinogen level in a sample comprising:
 a first input for obtaining an attenuance signal over time indicative of a fibrin polymerization of said sample;   a second input for obtaining a reactant concentration signal over time indicative of a reactant concentration in said sample, wherein the reactant is any substance leading to the cleavage of fibrinogen to fibrin;   a simulation unit running a model using the reactant concentration signal as an input to provide a simulated attenuance signal over time; and   an evaluation unit configured to infer the fibrinogen level of said sample by comparing the attenuance signal over time with the simulated attenuance signal over time.   
     
     
         2 . Device according to  claim 1 , wherein the simulation unit is configured to provide to the evaluation unit multiple simulated attenuance signals over time for a range of fibrinogen levels. 
     
     
         3 . Device according to  claim 1 , wherein the evaluation unit is configured to extract one or more characteristic features from the attenuance signal and further one or more characteristic features from the simulated attenuance signal, wherein the evaluation unit is further configured to match the one or more characteristic features with the further one or more characteristic features. 
     
     
         4 . Device according to  claim 3 , wherein at least one of the one or more characteristic features and at least one of the further one or more characteristic features is defined by the difference between an initial attenuance and a final attenuance of the attenuance signal. 
     
     
         5 . Device according to  claim 1 , wherein the simulation unit is configured to rerun the model at least one more time with a parameter provided by the evaluation unit, such that an error between the attenuance signal and the simulated attenuance signal is minimized. 
     
     
         6 . Device according to  claim 1 , wherein the simulation unit is configured to run the model which uses at least one ordinary differential equation indicative of a chemical reaction of fibrin polymerization. 
     
     
         7 . Device according to  claim 6 , wherein a state variable of said at least one ordinary differential equation is the reactant concentration signal. 
     
     
         8 . Device according to  claim 1 , wherein the simulation unit is configured to run the model which uses a set of coupled ordinary differential equations, each being indicative of a chemical reaction involved in fibrin polymerization, and said set is being solved by the simulation unit numerically. 
     
     
         9 . Device according to  claim 1 , wherein the simulation unit is configured to run the model which uses at least a first algorithm to determine concentrations of proteins and protein complexes over time, a second algorithm to determine the average mass/length ratio of fibrin molecules from said concentrations, and a third algorithm to determine the attenuance of the sample from said mass/length ratio. 
     
     
         10 . Device according to  claim 1 , wherein the reactant concentration signal over time is interpolated from a time-discrete signal to a continuous signal using a reactant specific interpolation formula. 
     
     
         11 . System for determining a fibrinogen level in a sample comprising:
 a measuring unit for providing an attenuance signal over time indicative of a fibrin polymerization of said sample; and   a device according to  claim 1 .   
     
     
         12 . System according to  claim 11  further comprising:
 a further measuring unit for providing an actual measurement of a reactant concentration of said sample. 
 
     
     
         13 . System according to  claim 11 , wherein the measuring unit and said further measuring unit are configured to produce measurements of said sample in parallel. 
     
     
         14 . Method for determining a fibrinogen level in a sample comprising:
 obtaining an attenuance signal over time indicative of a fibrin polymerization of said sample;   obtaining a reactant concentration signal over time indicative of a reactant concentration in said sample, wherein the reactant is any substance leading to the cleavage of fibrinogen to fibrin;   running a model using the reactant concentration signal as an input to provide a simulated attenuance signal over time; and   inferring the fibrinogen level of the sample by comparing the attenuance signal over time with the simulated attenuance signal over time.   
     
     
         15 . Computer program comprising program code means for causing a computer to carry out the steps of the method as claimed in  claim 14  when said computer program is carried out on the computer.