New HLH registry aims to unlock secrets of rare immune disease

This study is a registry that collects information from 200 people with hemophagocytic lymphohistiocytosis (HLH), a rare condition where the immune system becomes dangerously overactive. Researchers will track how quickly HLH is diagnosed, what treatments are used, and what complications or long-term effects occur. The goal is to better understand the disease and improve future care.