Immune mechanisms in uremia

There is both clinical and experimental evidence that cellular and humoral immunity are suppressed in patients with renal insufficiency: observations in organ transplantation and in vitro stimulation of lymphocytes from uraemic patients, investigations of acute and late hypersensitivity reactions, the immune response after active immunization as well as changes of immunoglobulins and lymphatic organs in uraemia are discussed in the paper. The underlying mechanisms are complex and not yet fully understood. Lymphopenia, atrophy of the thymus gland, toxic serum factors, induction of enhancing mechanisms by certain serum fractions and metabolic defects of lymphocytes--all were shown to be involved or at least considered to be. At present, however, it is impossible to define their rank of importance and the exact place they may occupy in the genesis of this type of "natural immunosuppression".