[Anesthesia in Sebastian syndrome: a new hereditary macrothrombocytopenia]

The macrothrombocytopenias make up a heterogeneous group of disease involving thrombocytopenia and giant platelets; other clinical or laboratory findings, such as hereditary nephritis, sensorineural hearing loss, leukocyte inclusions, and cataracts, may also be present. The tendency to bleeding is highly variable and is due to decreased expression of the GP1b-V-IX complex on the surface of platelets, leading to altered platelet-vessel wall and platelet-platelet interactions. The 5 autosomal dominant giant-platelet disorders that are associated with macrothrombocytopenia are May-Hegglin anormaly, Epstein, Fechtner, and Sebastian syndromes, and Alport-like syndrome with macrothrombocytopenia. The mutation responsible is in gene 9 (MYH9) coding for the nonmuscle myosin heavy chain IIA that has been identified in the long arm of chromosome 22 (22q12.3-q13.2). The most recently described macrothrombocytopenia is Sebastian syndrome, consisting of thrombocytopenia with giant platelets and leukocyte inclusions. We report the case of a woman with Sebastian syndrome scheduled for abdominoperineal resection for rectal carcinoma. Preoperative studies revealed isolated thrombocytopenia (35,000 platelets/microL) and a mean platelet volumen of 13 fL. Preoperative prophylactic platelet transfusion was carried out with no adverse events. After a postoperative transfusion of packed red cells, needed because of abundant bleeding, clinical course continued to be satisfactory. The anesthetic implications of this syndrome are not well known because few cases have been reported in the literature, and none was found that describes anesthetic management. Nevertheless, thrombocytopenia and the tendency to bleeding present challenges to the anesthesiologist.