Transient lupus anticoagulant induced by adenovirus cystitis in a bone marrow transplant recipient.

Adenovirus-associated hemorrhagic cystitis (AdV-HC) is a serious complication of hematopoietic stem cell transplantation (HSCT) that requires hemostatic therapies to control severe hematuria. Here we present the case of a 65-year-old woman with acute myeloid leukemia who successfully underwent HSCT, but developed AdV-HC followed by adenovirus viremia. Marked prolongation of activated partial thromboplastin time (APTT) was observed, along with a decrease in all coagulation factors except prothrombin, raising suspicion of a coagulation factor deficiency. A workup including the APTT cross-mixing test, diluted Russell's viper venom time, and phospholipid neutralization assays revealed the presence of lupus anticoagulant (LA), indicating a thrombotic tendency due to LA associated with artifactual lowering of coagulation factors. Based on these findings, no hemostatic agents were used to manage macroscopic hematuria, and all coagulation test results spontaneously normalized with the resolution of adenovirus viremia, without any thrombus formation. Patients with AdV-HC and prolonged APTT should be screened for LA to avoid inappropriate use of hemostatic agents.