The prognosis is guarded with an overall mortality of 50%. Poor prognostic factors included<unk>  associated with malignancy, with half the patients dying by 1.4 months compared to 22.8 months for non-tumour associated<unk>  patients. Secondary<unk>  in some individuals may be self-limited because patients are able to fully recover after having received only supportive medical treatment (i.e., IV immunoglobulin only). However, long-term remission without the use of cytotoxic and immune-suppressive therapies is unlikely in the majority of adults with<unk>  and in those with involvement of the central nervous system (brain and/or spinal cord).
Hemophagocytic lymphohistiocytosis
Diffuse infiltrative lymphocytosis syndrome
Congenital self-healing reticulohistiocytosis
Thymoma with immunodeficiency
Langerhans cell histiocytosis
Blastic plasmacytoid dendritic cell neoplasm
Hereditary pyropoikilocytosis
Angioimmunoblastic T-cell lymphoma