Biological and environmental factors affecting ultrasound-induced hemolysis in vitro: 1. HIV macrocytosis (cell size).

This paper reports the results of a further test of the hypothesis that the extent of ultrasound (US)-induced cell lysis in the presence of a US contrast agent to enhance cavitational effects is a function of cell size. The present data support the hypothesis. Human adult erythrocytes in vitro derived from patients with HIV (n = 15) and apparently healthy individuals (n = 15) were compared for US-induced hemolysis in vitro. The anticoagulated whole blood from patients with HIV and macrocytic erythrocytes had significantly greater (p <0.0001) mean corpuscular volume (MCV) and a significantly greater (p <0.03) extent of US-induced hemolysis in vitro relative to blood from apparently normal, healthy individuals. As a control to determine if disease state (i.e., HIV infection per se) might be a contributing factor in US-induced hemolysis in vitro, the blood from patients with HIV and apparently normal MCVs (n = 15) was also tested against an additional population of apparently normal, healthy individuals (n = 15); there were no statistically significant differences in MCVs or US-induced hemolysis between the two groups (p >> 0.05). There were also no statistically significant differences in viscosities or hematocrits of the whole blood or plasma in vitro from HIV-macrocytic or apparently healthy individuals but, for all blood types, a pooled correlation existed between hematocrit and whole blood viscosity.