Resolution of possible acquired protein S deficiency after viral suppression in HIV infection

Current literature suggests an increased risk of venous thromboembolism (VTE) in people living with HIV (PLWH) with poorly controlled viraemia and immunodeficiency. VTE treatment guidelines do not specifically address anticoagulation management in PLWH. We report a case of a 33-year-old woman diagnosed with an unprovoked pulmonary embolism (PE) and deemed protein S deficient. Three years later, she was diagnosed with AIDS. Antiretroviral therapy (ART) was promptly initiated with viral suppression and immune reconstitution within 12 months. Eight years after her initial PE, the patient self-discontinued warfarin. Multiple repeat protein S values were normal. ART without anticoagulation has continued for 3 years with no thrombotic events. This case describes a patient with VTE presumably secondary to undiagnosed HIV with possible consequent acquired protein S deficiency. Additional research is needed to understand the characteristics of PLWH with VTE who may warrant long-term anticoagulation as opposed to shorter courses.