Late postoperative hemorrhage in a patient with undiagnosed COX-1 deficiency after third molar extractions.
Oral maxillofacial surgeons direct invasive procedures that often cause significant bleeding. Uncontrolled hemorrhage is a rare, yet serious, complication that can be seen in patients with thrombocytopathy. Platelets have 3 distinct roles in coagulation: initial adhesion, phospholipid externalization, and platelet aggregation.(1) Several types of platelet deficiencies, including defects of adhesion (Bernard-Soulier syndrome), defects of aggregation (Glanzmann thrombasthenia), and disorders of platelet secretion due to a deficiency of adenosine diphosphate (ADP) or cyclooxygenase-1 (COX-1).(2-4) COX has 2 isoforms: COX-1 and COX-2.(5,6) COX-1 is expressed constitutively in most tissues, and COX-2 is induced primarily by inflammatory mediators.(7,8) Although both isoforms are present in platelets, COX-1 is the major isoform that contributes to coagulation, because it is critically important in the formation of thromboxane A2 (TXA2) by way of the arachidonic acid (AA) pathway.(9) AA is a potent inducer of platelet aggregation.(1,3,4) When AA is exposed to an activating agent, such as ADP, it undergoes a series of enzymatic reactions that culminates in the production of TXA2.(10) TXA2 is the predominant product of the COX-1 pathway and is a major metabolite of AA in platelets. TXA2 is necessary for normal platelet function. Therefore, the inhibition of, or a deficiency in, COX-1 will compromise the AA pathway, thereby reducing platelet secretion and altering normal platelet aggregatory function.(1,3) COX-1 deficiencies are usually caused by drug interactions with the enzyme itself. In addition, studies have identified genetic mutations that can result in COX-1 deficiency.(2) We present the hospital course, management, and diagnosis of a patient with an undiagnosed COX-1 deficiency who had had third molars removed in a private office. To our knowledge, this is the first case of COX-1 deficiency diagnosed after exodontia documented in English studies. In addition, we reviewed the published data of this rare disorder that has significant clinical implications.
Chief Resident, Division of Oral and Maxillofacial Surgery, Yale-New Haven Hospital, New Haven, CT. Electronic address: Jesse.Doscher@yale.edu.
Jesse C
JC
Doscher
Division of Oral and Maxillofacial Surgery, Yale-New Haven Hospital, New Haven, CT; and Private Practice, Milford, CT.
Fedele N
FN
Volpe
D000293:Adolescent; D016063:Blood Loss, Surgical; D051545:Cyclooxygenase 1 / Q000172:deficiency*; D017707:Erythrocyte Transfusion; D005260:Female; D005500:Follow-Up Studies; D006488:Hemostasis, Surgical / Q000379:methods; D006489:Hemostatic Techniques; D006490:Hemostatics / Q000627:therapeutic use; D006801:Humans; D008964:Molar, Third / Q000601:surgery*; D006472:Oral Hemorrhage / Q000209:etiology*; D019106:Postoperative Hemorrhage / Q000209:etiology*; D014081:Tooth Extraction / Q000009:adverse effects*
D006490:Hemostatics; D051545:Cyclooxygenase 1; C496511:PTGS1 protein, human