Table 1.
Natural barriers | Fragile, thin and/or edematous skin Alteration of gastrointestinal motility, mucosal permeability and bacterial flora ↑ Gastrointestinal mucosal ulcerations |
Hepatic RES activity | Portosystemic shunting Kupffer cells – ↓ number, impaired function |
Cellular defense mechanisms | RES – ↓ activation, ↓ chemotaxis, ↓ phagocytosis, ↓ production of pro-inflammatory cytokines PMN – ↓ lifespan, ↓ intracellular killing activity, ↓ phagocytosis, ↓ chemotaxis |
Serum factors | ↓ Complement levels (C3, C4, CH50) ↓ Opsonic activity ↓ Protein C activity |
Iatrogenic and treatment-related factors | Invasive procedure and catheters Medications: immunosuppressive agents, proton pump inhibitors |
Other compelling factors | Malnutrition Alcohol drinking |
RES: Reticuloendothelial system; PMN: Polymorphonuclear neutrophil.