DIC

July 12, 2003
14:00 to 18:00
Hall 5
The International Convention Center, Birmingham


Chairman: K. Hoots, USA
Co-chairs:  I. Bokarew, Russia;; M. Levi, The Netherlands; J. Nielsen, Denmark;
N. Sakuragawa, Japan; C-H. Toh, UK; H. Wada, Japan


The following report and addendum summarize both an interim meeting of the subcommittee co-chairs held in Houston in February 2003 and the subcommittee meeting held in Birmingham in July 2003.  The latter meeting summarized implementation and recommendations concerning the DIC algorithm and committee progress to the entire membership of the DIC subcommittee and was verbally endorsed by those present.    

This is a summary of the DIC Subcommittee of the Scientific Standardizations Committee of the International Society of Thrombosis and Hemostasis held in Houston, Texas, February 14-16, 2003 at the University of Texas Houston Health Science Center.    

The agenda which was circulated to the committee prior to the meeting consisted of four (4) major areas of discussion.  The first was a review of the DIC Subcommittee Algorithm which was published in the Journal Thrombosis and Haemostasis in November 2001.  The intent was to examine sensitivities and specifities of the algorithm based on pilot studies done in at least 3 sites.  Also discussion was to center on how and if changes needed to be undertaken to the algorithm.  Second there was review of updates from the literature and experience with regards to clinical trials and potential trials.  In particular the PROWESS trial and the KYBERSEPT trial were discussed in great detail.  Number 3 on the agenda was any new endeavors to be undertaken by the committee with regard to the algorithm or other new efforts on behalf of the subcommittee.  The final intent was to set the agenda for the Birmingham meeting of the DIC Subcommittee at ISTH in July 2003.  Attendees at the meeting were the following: Dr. Keith Hoots was the host, excused was Dr. Marcel Levi who because of commitments in his home country of the Netherlands was unable to attend, Dr. Cheng Hock Toh from Liverpool, Dr. Hideo Wada from Tokyo, Dr. Carl Erich Dempfle from Hamburg, Dr. Fletcher Taylor from Oklahoma City, and Dr. Mathias J‡rs from Aventis Behring (meeting sponsor) were the attendees present.  

Introduction:  The ultimate aim of this Subcommittee by consensus is to improve outcomes in individual patients who have diseases that lead to Disseminated Intravascular Coagulation (DIC).  It was agreed that overt DIC is the final common pathway in that in many if not all cases it is initiated or at least exasperated by the enzyme thrombin which behaves in a very chemically promiscuous way.  The consensus approach to be taken from the meeting was as follows:

1) to define the process to apply the DIC algorithm across wide spectrums of clinical diseases and geographies and multiple medical specialties.  Number two was to validate the scoring of the algorithm in diverse groups with both overt and non-overt DIC.  Initially next steps about the algorithm were discussed in significant detail.  The first effort was to examine validation progress on overt DIC.  Data was presented from Liverpool, Tokyo and from Hamburg related to efforts to apply the algorithm in clinical populations with DIC.  This was an update of information that was presented at the last DIC Subcommittee in Boston in August 2002.  In addition, some new information was provided by Dr. Wada with regards to comparing the DIC score of our committee with an ICU/ER score which was an outgrowth of the original Japanese Ministry of Health DIC score which served as one of the basis for our developments of this algorithm.

2) We discussed the status of possible multicenter validation of the overt DIC algorithm and felt that we would benefit greatly from the presence of Dr. Levi to discuss protocol implementation practices and to reach among ourselves definitive statements concerning inclusion, exclusion and analysis criteria to be utilized for such studies.

3) We wish to define the "message" to be conveyed to the broad medical community concerning this ISTH algorithm and to continue updating comparisons between it and the ICU/ER algorithm in Japan versus the traditional Japanese Ministry of Health and Welfare algorithm.  Dr. Wada will take the lead on this and will continue to make such comparison in groups of multiple types of patients with multiple insults and injury.

4) With Dr. Dempfle as the discussion leader we examined the role of fibrin markers in the scoring system itself.  It was recommended that cutoffs between 0, 1, and 2 that score on the DIC overt and non-overt scale adopt ranges that are compatible with the SSC Fibrinolysis Subcommittee on which Dr. Dempfle sits.  Specifically for D-dimer we proposed that if it was 1 microgram per mil > than 1 it would score 2 but if it was £ 4; greater than 4 micrograms per mil we would score 3 in the overt/non-overt scale was the recommendation that was entertained.  Further discussion should follow.  

5) We also proposed d-Dimer as the ideal fibrin marker.  We left open the option for fibrin degradation products or new fibrinolytic or fibrin markers to be employable in the algorithm itself.  From the data provided by Dr. Dempfle we recognized the need that a specific marker of excess fibrin degradation be identified and efforts to validate it for possible implementation be undertaken.  This is critical for future studies to determine whether proteolysis of fibrin confers added predictability to what is already conferred by the presence of markers of fibrin deposition.  

6) We queried whether an additional list of fibrinolytic markers would be beneficial in the algorithm.  No consensus was reached at this time we will plan to return to this discussion.  

7) It was noted that there were a number of confounding phenomenon making utilization of fibrin markers and fibrinolytic markers more problematic: for example, increase plasminogen activator inhibitor 1 (PAI-1) correlates with DIC at least in sepsis and would be expected to actually decrease fibrin degradation products and therefore may compound the interpretation in the acute setting.  Further examination of this possible confounding effect needs to be undertaken with the consensus of the Subcommittee.

8)  We entertained the question "Does the scoring for Fibrin Marker(s) need to change in light of heterogenecity of assay results of D-dimer?"  Specifically since multiple assays exist for D-dimer it is important that validation for each specific marker be present at the site which proposes to use that D-dimer test.  The other thing about overt DIC was that we agreed that it could not be used as a trend marker unlike that the situation that makes it with the non-overt DIC.  

The next part of the committee presentation centered on clinical trials in DIC that have been completed.  Both the PROWESS trial and the KYBERSEPT trial were reviewed on a broad basis.  It was noted of particular import to this Subcommittee that both of these trials had sepsis as the inclusion criterion rather than DIC, even though the results are most frequently identified as either success or failure to treat DIC.  It was the consensus of the group that future trials should in fact have DIC as an inclusion criterion if in fact the conclusions were going to be drawn concerning success or failure of the treatment of DIC.  

With regards to the role of DIC algorithm in future clinical trial designs an extensive discussion was undertaken.  It was felt that several things needed to be improved in the algorithm scoring system in order to maximize its potential for such an application in trial design.  Specifically two issues were noted. 

1) It was felt that markers of neutrophil activation such as elastese as a specific indicator of cell interaction and upregulation in response to injury would be needed to meet the needs for certain trials. 

2) In addition, other clinical parameters need to be examined carefully.  It is essential that critical ascertainment for an individual patient must be made about where along the non-overt/overt continuum he/she is at the time of initiation or their entry into a trial.  It was felt that this was a critical point in order to assess whether in fact progression/regression or a static situation had been achieved in response to therapy.  The "TIME" dimension for progression along the continuum is absolutely critical for this assessment.  That is to say, we need to be able to provide measurements as prescribed by the Algorithm in a sequence of clinical/laboratory events.  This is so that the definition for inclusion in the trials can identify targeted patients who fall within a narrow window along the continuum or at least so that they can be stratified during the analysis accordingly.  

Other issues included the following: the biokinetics need to be defined better for categorical microangiopathic states.  Efforts of Dr. Wada and his other Japanese colleagues have looked at static determinates of DIC and microangiopathic states, comparing for example HUSTTP with full-blown DIC with other inflammatory states that are not microangiopathic.  This provides a very useful scenario for validating our algorithm.  It is important however that the sequence of either progression or lack of progression in molecular markers be defined for each of these generic clinical situations so that in clinical trials the right patients can be included or excluded appropriately.

2) We need to design a way so that the impact of therapy on the biokinetics of the DIC continuum can be assessed.  This will of necessity require further elucidation of the transition between overt and non-overt DIC.  

3) It was felt that future directions would require assessment of genomic differences perhaps  proteomic differences in individual subpopulation groups and the potential impact that each may have on propensity to progress, regress or remain static in response to therapy. One of the things that clearly is needed (at least for each of the markers to be employed) is a consistent longitudinal graph of the biological marker parameter versus time with an attached confidence interval.  This needs to be performed longitudinally for each of clinical conditions so that investigators can best decide where in the continuum these research subjects lie.  

Finally, in order to expedite this and other uses with regards to both the non-overt and the overt algorithm, specific recommendations to modify and improve the Algorithm were made at this meeting of the Subcommittee.  These consisted of three specific recommendations:

1) To specify specifically which fibrin marker assay should be used for example D-dimer;

2) DO NOT mix fibrin marker assays in the same study unless that is the comparison for the study design to be examined; and

3) change the prothrombin measurement to the Prothrombin ratio as defined by QUICK this is in distinction to the INR.  It is calculated at 70% of the normal range for the specific laboratory control of the laboratory used in the assessment.  

The final endeavor for this committee meeting was to outline the next steps for further assessing and then implementing the algorithm.  With regards to non-overt DIC, since DIC has been summarized above, the following issues or recommendations were made:

1) As a major criteria, change "soluble fibrin/fibrin degradation product" in the algorithm to the term "Fibrin Marker" and see the discussion above under overt.  

2) A cut-off for the D-dimer needs to be defined in terms of milligrams per ml in most assays twice the upper limits of normal range should be used as a defining principle.   

3a) For the prothrombin time use the QUICK ratio as defined above in the overt discussion.  

3b) Use only platelet counts that are pre-transfusion because obviously there is a confounding effort in the analysis if post transfusion platelet counts are used.

4)  If anti-thrombin concentrates or activated Protein C concentrates or non-activated Protein C concentrates have been utilized to treat the patient one cannot use the specific criteria for entry into this algorithm.  

5) In recalculating the non-overt score one needs to take into consideration specific criteria about whether and what impact the use of fresh frozen plasma may have had in the starting score and in the progression of the score.  One of the questions that was raised was whether such assessment should be part of our ongoing trend analysis in the implementation of the algorithm.

6)  There needs to be a vigorous attempt at "normalizing" the biological marker data parameters.  For instance, in the non-overt we indicate that either Protein C or Antithrombin can be used to score over time.  It was felt by the Subcommittee that we need to be consistent that one cannot measure one parameter on one point in time and then switch to another parameter on another point in time and score.  It must be decided apriori which biological markers are to be implemented for the full duration of the use in the individual patient in the non-overt algorithm.  

7) It was felt that thrombin Antithrombin or TAT should not be utilized because it cannot be done in real time.  It can only be done after the fact.  

8)  It was felt that Wave Form Analysis could be used prospectively but that it should be normalized as an extra test in the scoring so that both validity could be felt and so that over sampling of biological parameters do not increase the statistical likelihood of error.  

9)  It was felt strongly that for the non-overt algorithm we need an endothelial and a polymorph nuclear neutrophil activation set of markers.  These need to be able to be done in real time.  Examples that might be applicable include thrombomodulin and elastese; markers of fibrinolytic inhibitors such as PAI-1 the latter would be very useful for use in the non-overt algorithm in particular because of the demonstrable role that it seems to play in the evolution of sepsis in particular.  

10) We need to be much more aggressive in defining outcome measures in our effort to pilot the   non-overt algorithm.  We need to know the answers to the following specific questions: 1) How many of those who enter into the non-overt algorithm proceed to overt DIC by the criteria we have defined?  2) For both overt and non-overt uses of the algorithm we need to know exactly how many people die and whether they die from DIC or from some other cause in order to validate the overall use of the algorithms.  3)  We need to be able to show how many individual subjects show significant improvement as they go from the use of the non-overt algorithm towards the use of the overt algorithm.  For example, if they start with DIC what is the impact of therapy; if they start without DIC what is the impact of therapy in preventing or allowing progression to DIC.  We clearly need prospective data to confirm these retrospective analyses that have been done to date.  And finally

11) we need to know the timing of the use of the algorithm specifically, we need to know (1) how often can you reapply the algorithm if at all; (2) how many times can you use it within a protracted course within the same individual; and (3) over what period of time over what duration of time can the algorithm be applied?  The consensus was that the first step the algorithm should not be applied more often than daily because of the problems created by repeating sampling error that this would introduce into assessing the validity of the algorithm.  

The final undertaking of the committee was to recommend a program outline for our subcommittee meeting of ISTH in Birmingham.  Some discussion was undertaken.   Since we hadn’t previously discussed it it was felt that it might be very helpful to look at both protease activated receptors those of particular interest with thrombin activation such as PAR-1and PAR-2.  Drs. Hoots and Taylor recommended Shaun Coughlin from the University of California-San Francisco who has written an excellent review on this in Nature.  Dr. Hoots agreed to contact Dr. Coughlin with regards to his possible availability for speaking at our meeting.  Two other suggestions were made, one was Dr. Ruf from the Scripps Institute in La Jolla who is also an expert in the PARs and Dr. Nigel Mackman also from Scripps who is an expert in phospholipid services where proteases bind and the importance of enzymes such as "scrambalase" that change the phospholipid services in response to injury signals.  One of the things that we thought would be interesting is reviewing recent data that the endothelial Protein C receptor signals through a PAR-2 receptor to examine how this might somehow be related.

Our final recommendation is that we establish a World Working Group for DIC.  It would be expected that the committee co-chairs from our committee would work with colleagues in the field of critical care, sepsis and trauma and other related fields for which the algorithm would have particular relevance.  Dr. Dempfle and Dr. J‡rs recommended the German Sepsis Group and Dr. Taylor recommended Dr. Gary Kinasewitz, MD at the University of Oklahoma who is a Pulmonologist and an Intensivist who has worked extensively with him as potential members of such a working group.  These issues decided, we adjourned the meeting and the intent was for Dr. Hoots to summarize the proceedings and distribute them to the subcommittee co-chairs first and after the refinement perhaps to circulate this information at our meeting in Birmingham.      

Addendum

The meeting of the subcommittee was held on Saturday, July 12, 2003 14:00 – 18:00 at Hall 5 of the ICC in Birmingham, UK.  Dr. Matthias Reiwald presented a mini-symposium lecture entitled "Interaction of Coagulation Proteases with cellular receptors and phospholipid cell surfaces: Proteases Activated Receptors (PARs) and Inflammation, Possible dysregulation in DIC."   Dr. Toh presented the Liverpool experience using the overt and non-overt algorithms and Dr. Wada presented comparison studies between the SCC algorithms and the ongoing algorithms undergoing modification from the Japanese Scientific Coagulation Committee/Japanese Ministry of Health and Welfare.   In addition Dr. Marcel Levi applied the overt algorithm to the data from the PROWESS study which indicated that the overt algorithm was very predictive of mortality in the APC treated cohort.  In addition Dr. Carl-Erik Dempfle of Mannheim, a liaison from the Fibrinolysis Subcommittee presented a simple data on the role of marker on fibrin cleavage in the DIC algorithm and presented the first quantitative measures included recommendations, of how d-Dimer levels should be stratified for scoring in the overt DIC algorithm.  The SCC attendees then discussed optimal plans for future studies and modifications to the SCC approved algorithms.  Plans for a future meeting prior to or before SCC meeting in Venice were discussed by the DIC SCC subcommittee chairs and will be coordinated by the chair. 

Respectfully submitted: W. Keith Hoots, MD