Impaired granulocyte formylpeptide-induced superoxide generation in chronically ill, malnourished, elderly patients

Objective. Protein-energy malnutrition (PEM), often occurring in patients with chronic disease, is associated with a decreased capacity to combat infections. In this study we assessed polymorphonuclear neutrophil (PMN) superoxide anion ( O-2(-),) formation in elderly PEM patients with various chronic diseases. Design and subjects. Nineteen patients (75 ii years), with body mass index 17.1 +/- 0.4, and 19 age-matched healthy controls were included. Fourteen patients and 14 controls were re-examined in a 3 month follow-up. Setting. A service of internal medicine at a university-affiliated hospital. Interventions. Eight patients were prescribed a dietary liquid supplementation during the observation period, Main outcome measures. Superoxide production in PMN induced by fMLP (a receptor ligand) and phorbol myristate acetate (PMA), which acts directly on protein Kinase C, Results. fMLP-induced superoxide generation in the malnourished patients was 55 +/- 5% of that of the controls. However, the patients retained their capacity, 108 +/- 6% of control PMN generation, to respond to PMA, In those who received formula supplementation, fMLP-generated O-2(-),- production levels were 48 +/- 8 and 73 +/- 13% (P = 0.12) of those of controls at the start and after 3 months, respectively. Corresponding figures in those who were not prescribed supplementation were 57 +/- 8 and 64 +/- 4% (P = 0.55). Conclusion. Possibly contributing to reduced host defence, receptor ligand-induced PMN generation of O-2(-) is significantly lower in chronically ill, elderly patients with PEM than in age-matched healthy controls.