Children and Adult Hemophagocytic Syndrome (HLHa)

Inclusion Criteria: Major criteria: * hemophagocytosis found in a specimen histology. * Fever * Splenomegaly Minor criteria: * adenopathy * cytopenia\> 2 cell lines Hemoglobin \<9 g / dl (less than 4 weeks and\> 12 g / dl) Platelets \<100 000 x 10 / l Neutrophils \<1 10 / l * hypertriglyceridaemia and / or hypofibrinogenaemia Elevated triglycerides\> 3 mmol / l Fibrinogen \<1.5 g / l * Ferritin\> 500 microg / L These criteria will be those used for the diagnosis of HLH in adults: One major criterion and two minor (including hyper ferritin or hypertriglyceridemia) 3 minor criteria (including hyper ferritin or hypertriglyceridemia) Exclusion Criteria: * Pregnant women * A person under guardianship * Patients under the age of 2 years