Splenic function in acute leukemia.

Abstract

Spleen function was evaluated in 36 patients with acute leukemia by enumeration of pitted erythrocytes and analysis of clearance from circulation of heat-damaged 99mTc-labelled erythrocytes (HDE). At diagnosis, the mean percentage of pitted erythrocytes was significantly higher in the patient group (4.04 +/- 7.19%) than in the control group (0.41 +/- 0.35%; p < 0.01), suggesting the occurrence of a splenic hypofunction in a high proportion of the patients. Accordingly, the clearance of HDE showed a pattern of splenic hypofunction in 4 out of 7 patients, based on reduced values for the parameters C20 (overall clearing function of the spleen), K (the rate constant of HDE irreversibly trapped) and K/K1 + K (the fraction of HDE entering the spleen undergoing permanent removal). After successful treatment, the pit counts decreased in all reassessed patients, returning to normal values in 10 out of 12 patients with high pit counts at diagnosis. Additionally, two patients with normal pit counts at diagnosis presented borderline results for the parameters C20 and K, which may suggest a slight splenic hyperactivity in these patients. These results demonstrate, for the first time, the presence of functional spleen abnormalities in patients with acute leukemia.