George, This is not really a coag question but relates to an issue we see intermittently in our clinical lab. It is the problem of receiving clotted body fluid specimens with the request of a cell count to be performed. While educating the clinician to put the specimen in an anticoagulant tube is ideal to avoid this problem, we do get these requests at times. Since the specimen is not easily recollected, we do not uniformly reject them but do the analysis with a disclaimer. I was wondering if you had any experience or have heard of anyone actually introducing a fibrinolytic agent to break up the clot to be able to perform a more useful evaluation? I remember back in my med tech days that we used to add protamine sulfate to dialysis patient specimens to activate the tubes to clot and wondered if anyone has thought of doing the opposite in these clotted body fluid specimens. I appreciate your thoughts on this question. Thank you in advance. Dr. Bruce King.
Hello, Dr. King, and thank you for your question. You sent this on July 2, and I apologize for the delay. I know of no precedent for your recommendation nor have I seen anything published, however, just as an opinion, I suggest you pursue the idea. We’ve used hyaluronidase, which depolymerizes hyaluronate in synovial exudates to reduce viscosity in preparing for a cell count and it seems like the same principle would work in pleural, pericardial, and peritoneal fluids. We aren’t hoping for rigid accuracy in a fluid count, anyway, and you’ll probably use a disclaimer similar to the one you are using now.
You would want to use a fibrinolytic that preserves cell morphology so you can identify neoplasia and one that produces no crystals. I’d suspect a tissue plasminogen activator, streptokinase, or urokinase would work. We possess no body fluid normal ranges; I suspect most of us just compare results to cerebrospinal fluid normals. I’ve contacted several body fluid experts to learn if I am missing any limitations, so please watch for comments below.
Jul 15 2014
Comments (1)
Fibrinolysis
I am not sure if any cell counts are useful from clotted bod
I am not sure if any cell counts are useful from clotted body fluid specimens. The clots, it seems to me, are going to contain a great deal of cross-linked fibrin, with entrapped RBCs and whatnot. Other than ascitic, CSF and synovial fluids, here we do not consider “cell counts” as very useful for diagnostic purposes. Instead, on chest fluids, we report out only a differential, regardless of whether it is clotted or not.