A Challenging Case of Kaposi Sarcoma Inflammatory Cytokine Syndrome

Kaposi Sarcoma Inflammatory Cytokine Syndrome (KICS) is a serious, uncommon disease that occurs in patients who are positive for HIV and human herpesvirus-8 (HHV-8). It is characterized by a constellation of clinical findings, including fever, weight loss, and fluid retention, as well as a lack of multicentric Castleman disease (MCD) features on histopathology and an elevated serum HHV-8 viral load. Diagnosis is often delayed, and treatment options are limited, culminating in high mortality rates. We hereby present a 32-year-old male patient with HIV who was untreated for a few years and came with fever, night sweats, pancytopenia, and widespread adenopathy. A thorough evaluation of opportunistic infections was unremarkable. Clinically MCD was suspected, but lymph node biopsy only showed Kaposi sarcoma (KS) with no characteristic features of MCD. However, with clinical deterioration, KICS was strongly suspected. Kaposi sarcoma immune reconstitution syndrome (KS-IRIS) was also a possibility as the patient was restarted on antiretroviral therapy. Rituximab was commenced, but the patient suffered a cardiac arrest and could not be revived. Alternative diagnosis must be explored in patients with HIV presenting with constitutional symptoms, cytopenia, and adenopathy after opportunistic infections and malignancies are ruled out. If they have KS with HHV-8 positivity and there is a lack of characteristic features of MCD in lymph node biopsy, prompt suspicion of KICS should be made, and treatment with rituximab and/or chemotherapy should be instituted rapidly. KS-IRIS is also possible if patients have recently received antiretroviral therapy and have a rapid decline in viral load and increase in CD4 counts (immunological recovery). HHV8 viral load levels may help to distinguish between these two inflammatory conditions.