Intravascular Large B‐Cell Lymphoma Presenting as Systemic Capillary Leak Syndrome With Immunological Phenomena: A Case Report

Intravascular large B-cell lymphoma (IVLBCL) has a high mortality rate, partly due to its heterogeneous presentation and rarity. We present a case of a 73-year-old woman who came into the emergency room in need of fluid resuscitation, interpreted as septic shock. However, broad-spectrum antibiotics gave no resolution, and no causative agent was found. Further physical examination showed proximal muscle weakness, Raynaud's phenomenon, and calcinosis cutis. During 3 weeks of admission, vasopressor support was required continuously due to a capillary leak syndrome. The patient passed away. The underlying malignancy was only revealed at autopsy. To the best of our knowledge, this is the first case of IVLBCL with hypovolemic shock due to systemic capillary leak syndrome in combination with a wide range of immunological phenomena.