Today we welcome Jennie Y. Law, M.D., Assistant Professor of Medicine here at the University of Maryland. Dr. Law is a true home grown talent, doing both her medical school and medicine residency here at the University of Maryland before leaving to do her fellowship in Hematology/Oncology at UT Southwestern down in Dallas, Texas. Today she is here to talk about Hemophagocytic Lymphohistiocytosis (HLH), a topic that has puzzled internists, intensivists, and hematologists alike. Review the pathophysiology, learn the criteria for diagnosis – both the HLH 2004 criteria and the newer HSCORE – and go through her treatment algorithms. See why and how you may be overlooking this important diagnosis in your patients!