Here is an interesting case study message from Boriana Parvez, a health care provider, location not provided.
I’m caring for a full-term female neonate currently two weeks old who presented at three days of life with bilateral subdural bleeds and an intraparenchymal bleed. Her initial prothrombin time (PT) and partial thromboplastin time (PTT) were 73 and 133 seconds, respectively, and platelets 23,000/uL. She was given fresh frozen plasma (FFP) and her PTT corrected to 24 but her PT remained 75 seconds. The platelet count corrected without therapy.
The next day her PT was still 75 seconds and PTT had risen to 133 seconds. Her fibrinogen was markedly reduced at 50 mg/dL. FFP corrected the fibrinogen and PTT but the PT remained 75 seconds. On this basis we speculated that she has a factor VII deficiency, but factors V, VII and X are all normal. At this time she developed thrombocytosis at 1,500,000/uL.
We conducted a mixing study that normalized the PT, excluding the presence of inhibitors. Any thoughts on what is the diagnosis? Is a lab error possible?
Hello, Boriana Parvez, and thank you for your interesting case study question. I’ve shared this with two experts, Dr. Larry Brace of Edward Hospital, Naperville, IL and Mr. Dave McGlasson of Wilford Hall USAF Hospital, San Antonio, TX. Here is a summary of our communications.
Given the consistency in repeated results, it appears your laboratory results are reliable. Could it be the neonate had somehow received heparin after birth? This could account for the bleeding and the laboratory results you report. If you’ve been able to retain any of the original specimen, a thrombin time or anti-Xa heparin assay could reveal presence of heparin.
Assuming no lab error and no heparin, factor VII deficiency is a remote possibility, although it does not explain the initially prolonged PTT. You may wish to ask whether the factor V, VII and X assays were performed subsequent to FFP administration. If so, they could be influenced by the presence of factors provided by the FFP. However, owing to its low plasma concentration and short half-life, factor VII typically remains low after FFP in someone who is factor VII deficient.
Factor II (prothrombin) deficiency could also account for the laboratory results, but is perhaps too rare to consider in the differential.
The strongest possibility is congenital hypo- or afibrinogenemia. Your PT method could simply be more sensitive than your PTT to the fibrinogen level. We recommend you continue to perform fibrinogen assays, including antigenic assays (immunoassays) if available to help reach this conclusion.
Again, thank you for your case. This message is sure to generate additional comments from other Fritsma Factor expert subscribers. Geo.