Impaired splenic function in elderly people.

Splenic function was assessed in subjects aged 70 years or over by counting pits in erythrocytes viewed under differential interference contrast microscopy. An increased percentage of pitted cells has previously been described after splenectomy and in medical hyposplenism. The mean percentage of erythrocytes with one or more pits was significantly higher in 40 elderly patients (3.4%) than in 40 younger patients (1.6%), confirming the results of a previous study on a Brazilian population. There was greater variability of splenic function in the elderly subjects with a subgroup with a greatly increased percentage of pitted erythrocytes. Impaired splenic function may predispose elderly patients to pneumococcal infection. This relationship deserves further study.