| Immunosuppressive therapy |
| Cytotoxic chemotherapy for malignancy |
| Treatment of autoimmune disease |
| Bone marrow ablation prior to transplantation |
| Treatment or prophylaxis of graft-versus-host disease following bone marrow transplantation |
| Treatment of rejection following solid organ transplantation |
| Microbial infection |
| Viral infection |
| HIV, AIDS |
| Measles |
| Herpes group viruses (HSV 1 or 2, EBV, CMV, VZV) |
| Bacterial infection (superantigens) |
| Mycobacterial infection |
| Parasitic infestation |
| Malignancy |
| Hodgkin disease |
| Chronic lymphocytic leukemia |
| Multiple myeloma |
| Solid tumors |
| Disorders of biochemical homeostasis |
| Diabetes mellitus |
| Renal insufficiency/dialysis |
| Hepatic insufficiency/cirrhosis |
| Malnutrition |
| Autoimmune disease |
| Systemic lupus erythematosus |
| Rheumatoid arthritis |
| Trauma |
| Burns |
| Environmental exposure |
| Radiation |
| Ionizing |
| Ultraviolet |
| Toxic chemicals |
| Other |
| Pregnancy |
| Stress* |
| Asplenia/hyposplenism |
| Allogeneic blood transfusion |
| Aging¶ |
