Long-term remission of Kaposi sarcoma-associated herpesvirus-related multicentric Castleman disease with anti-CD20 monoclonal antibody therapy.

Kaposi sarcoma-associated herpesvirus (KSHV)-related multicentric Castleman disease (MCD) is potentially lethal. Growing evidence indicates that, as in Epstein-Barr virus-driven lymphoproliferative disorders after transplantation, KSHV DNA burden in peripheral blood mononuclear cells (PBMCs) may represent the most accurate marker of disease activity. This report describes a patient with human immunodeficiency virus who was followed up clinically and by quantitative polymerase chain reaction for KSHV DNA sequences in PBMCs for more than 3 years following the diagnosis of KSHV-related MCD. Therapy with the antiherpesvirus agent cidofovir, antihuman interleukin-6 antibody BE-8, antiblastic chemotherapy, and combination antiretroviral agents did not achieve durable clinical or virologic remission of the disease. By contrast, administration of the anti-CD20 monoclonal antibody rituximab was well tolerated and allowed a 14-month remission of clinical symptoms and KSHV viremia. Rituximab should be added to the therapeutic armamentarium for KSHV-related MCD.

Role of PCR in diagnosis and prognosis of visceral leishmaniasis in patients coinfected with human immunodeficiency virus type 1.

A group of 76 consecutive human immunodeficiency virus (HIV)-positive patients with fever of unknown origin (n = 52) or fever associated with pulmonary diseases was evaluated in order to assess the usefulness of PCR with peripheral blood in the diagnosis and follow-up of visceral leishmaniasis. We identified 10 cases of visceral leishmaniasis among the 52 patients with fever of unknown origin. At the time of diagnosis, all were parasitemic by PCR with peripheral blood. During follow-up, a progressive decline in parasitemia was observed under therapy, and all patients became PCR negative after a median of 5 weeks (range, 6 to 21 weeks). However, in eight of nine patients monitored for a median period of 88 weeks (range, 33 to 110 weeks), visceral leishmaniasis relapsed, with positive results by PCR with peripheral blood reappearing 1 to 2 weeks before the clinical onset of disease. Eight Leishmania infantum and two Leishmania donovani infections were identified by PCR-restriction fragment length polymorphism analysis. PCR with peripheral blood is a reliable method for diagnosis of visceral leishmaniasis in HIV-infected patients. During follow-up, it substantially reduces the need for traditional invasive tests to assess parasitological response, while a positive PCR result is predictive of clinical relapse.