Mechanisms of Recovery From Neutropenia Induced by Hemodialysis

Profound, transient neutropenia is observed early in hemodialysis. The present studies were performed during 11 twin-coil dialyses in eight patients with chronic renal failure to determine if the rapid recovery reflects remobilization of sequestered neutrophils and/or if marrow reserves are utilized. In five studies, in vitro cell tagging with diisopropylfluorophosphate-³²P (DF ³²P) and reinfusion were performed 4-6 hr before routine hemodialysis. In all 11 studies a marked decrease of the absolute neutrophil count occurred within 15 min of starting blood return from the coil. In nine studies carried on over a sufficient period of time, a rebound of the neutrophil count to levels significantly higher than the highest control counts occurred by 1½-3½ hr after starting dialysis. In the radioactive studies during the rebound phase, most or all of the expected number of labeled neutrophils returned to the circulation, but simultaneously in all cases a large number of extra unlabeled neutrophils appeared in circulation. Since there are two sources for additional circulating neutrophils—the marginated pool and the marrow reserves—and since the marginated pool under the study conditions would be expected to have the same specific radioactivity as the circulating pool, the data are consistent with the hypothesis that there was an immediate marrow response to neutropenia.