A rare HIV-associated hyaline vascular multicentric castleman disease with good early response to single-agent rituximab: A case from Tanzania

Background: Castleman's Disease (CD) is a diverse group of non-neoplastic lymphoproliferative disorders characterized by lymphoid endothelial and follicular hyperplasia. Human Immunodeficiency Virus (HIV)-associated Human Herpes Virus type-8 (HHV-8) CD is a form of CD affecting HIV-positive individuals with concomitant HHV-8 infection as the aetiological driver. While the prevalence of HIV and HHV-8 is high in Sub-Saharan Africa (SSA), there are however very few reported cases of CD from the region. This might reflect a high rate of misdiagnosis and under-reporting of HIV-associated HHV-8 CD in limited-resource settings. If diagnosed early and precisely, the HIV-associated HHV-8 CD can be successfully treated with chemotherapy and/or single-agent targeted therapy (rituximab), regimens that are increasingly becoming available. Case presentation: We highlight a rare case of HHV-8 associated Multicentric Castleman Disease (MCD) in an HIV- positive individual who presented with lymphadenopathy, haemolytic anaemia, monoclonal gammopathy and atypical hyaline vascular variant and showed good early response with single-agent rituximab. Conclusions: A high index of suspicion is needed to diagnose CD, especially in regions where infectious diseases are common and share clinicopathological features with malignant diseases. Early diagnosis is the key to appropriate management, with a potential cure for the disease.