Increased polymorphonuclear leucocyte rigidity in HIV infected individuals

Aim-Individuals with human immunodeficiency virus (HIV) infection were eval uated for evidence of abnormal polymorphonuclear leucocyte (PMN) rigidity, which can alter capillary blood flow. Methods-The transit time of individual PMN through 8 mu m pores in a cell t ransit analyser was used as a measure of cell rigidity. PMN transit time wa s compared between HIV infected individuals (n=45) with and without CMV ret initis and HIV negative controls (n=17). Results-Transit times were longer for PMN from HIV infected individuals tha n for PMN from controls (p<0.001). PMN from HIV infected individuals with C MV retinitis (n=13) had longer transit times than PMN from those without CM V retinitis (n=32, p<0.001). Transit times were longer in HIV infected indi viduals with lower CD4+ T lymphocyte counts (p<0.001). Regression analysis indicated that the relation between transit times and the presence of CMV r etinitis could not be explained solely on the basis of low CD4+ T lymphocyt es. In HIV infected individuals, mean transit time was not correlated with age, blood pressure, or serum creatinine, cholesterol, or triglycerides. Conclusions-HIV infected individuals appear to have increased PMN rigidity, a cellular change that might be involved in the pathogenesis of HIV relate d retinal microvasculopathy. PMN rigidity appears to be related to severity of immune dysfunction. PMN rigidity may remain high in patients with CMV r etinitis after elevations of CD4+ T lymphocyte counts that result from pote nt antiretroviral therapy.