Pathoanatomical features of the kidney in myelomonocytic and chronic lymphocytic leukemia.

The kidneys of 18 autopsy cases of myelomonocytic leukemia (MML) were examined for MML-specific features. Nine cases of chronic lymphocytic leukemia (CLL) served as controls. The kidneys of the cases of MML showed macroscopically detectable signs of hemorrhagic diathesis and secondary uric acid diathesis more often than those of CLL. In the MML group most of the kidneys weighed more than the normal average for the corresponding age group, but the average renal weights for the 2 groups were about the same. Renal weight and grade of leukemic infiltration, particularly in MML, revealed no significant positive correlation. In most of the cases of MML there were unevenly distributed poorly defined leukemic, infiltrates in the renal cortex and medulla. The histology resembled that of pyelonephritis. In CLL, on the other hand, the leukemic infiltrates were usually sharply defined and localized in foci in the outer cortex and the corticomedullary border region. Renal dysfunction in cases of MML has been attributed by others to hyperlysozymemia. It was found occasionally but there was no MML-typical morphological substrate in our material. Hyaline droplet change of the tubular epithelium was more frequent and more pronounced in MML than in CLL. However, we also determined that it was nonspecific and that it was not a parameter of cell damage. Tubular hyaline droplet change and the morphological criteria of acute renal failure were not positively correlated with the degree of leukemic infiltration of the kidneys or with the leukemic proliferation as a whole. Instead, they were considered to be signs and symptoms of accompanying or secondary diseases which complicated the leukemia.