A Thrombotic Thrombocytopenic Purpura-Like Syndrome in HIV and Streptococcus pneumoniae Meningitis.

Thrombotic thrombocytopenic purpura (TTP) is a disorder characterized by the formation of diffuse thromboses in small blood vessels, which can result in neurological and renal impairment, fever, and purpura, among additional sequelae. TTP-like syndromes are disease processes that have similar signs and symptoms as TTP but without a severe deficiency in ADAMTS13 levels. We present a case of a young male with advanced human immunodeficiency virus (HIV) and Streptococcus pneumoniae meningitis presenting with a thrombotic microangiopathy (TMA). Although his ADAMTS13 level was not suggestive of TTP, at 54.4% (normal low ADAMTS13: >66.8% activity; severe ADAMTS13 deficiency: ≤10% activity), he improved only after plasmapheresis was initiated, supporting a diagnosis of a TTP-like syndrome likely due to his streptococcal meningitis. We discuss the importance of treating patients with TTP-like syndromes and advanced HIV with highly active antiretroviral therapy (HAART). We also highlight the increased prevalence of TMA and TTP among HIV patients and that many of these patients do not have a severe deficiency in levels of serum ADAMTS13.