Figure B. Pale necrotic lesion of lymph node shows small karyorrhectic debris and polymorphous cell population of surrounding cells (histiocytes, lymphocytes, plasmacytoid monocytes). (H&E x 400 ...

HLH is an immune deficiency disorder which happens when certain types of white blood cells, known as histiocytes and lymphocytes, become overactive and attack the body. It can be life-threatening ...