OBJECTIVE To determine the mechanism for the reduced polymorphonuclear leukocyte exudation in critically ill anergic patients. METHODS Prospective consecutive patient study. METHODS Tertiary care surgical intensive care unit. METHODS Eighteen patients with intra-abdominal injections were studied. METHODS Critically ill patients were stratified based on their delayed type hypersensitivity response to ubiquitous antigens. Polymorphonuclear leukocytes were isolated from blood and from exudate blister type skin windows. Adhesion and chemotactic surface receptors were measured, as was cytokine content and chemoattraction capacity of skin window fluid for control neutrophils. RESULTS Circulating neutrophils from anergic patients have increased CR3 adherence receptors compared with those neutrophils from reactive patients. f-met-leu-phe receptors are equal in number and C5a receptors are either significantly reduced in number or occupied with ligand. This same receptor pattern is maintained after neutrophil exudation in both patient groups. Serum and skin window fluid from anergic patients attracted less neutrophils in vitro and in vivo. CONCLUSIONS These data suggest two possible mechanisms for the reduced neutrophil delivery of critically ill anergic patients: a receptor-mediated increased adherence to vascular endothelium preventing diapedesis; reduced chemo-attraction potential of serum, and possibly, exudate fluid.