Persistent immunoglobulinuria in irreversible renal allograft rejection in humans.

To evaluate the extent of injury in short- and long-term renal allografts, the urinary excretion of IgG, IgA, and IgM was observed during acute rejection crisis. In reversible rejection, treatment resulted in prompt correction of immunoglobulinuria, whereas in irreversible crisis urinary immunoglobulin levels continuously increased in spite of the same antirejection treatment. A good prognosis in long-term allografts was shown by low levels of immunoglobulinuria; unstable graft function had higher levels. Immunoglobulinuria can be used as an additional test to evaluate the reversibility of acute rejection, and also has significance in the long-term situation.