Inflammation

Exam items lean on the lab trail: a rising ESR and C-reactive protein (CRP) signals active inflammation, but these are non-specific acute-phase reactants — they tell you something is inflamed, never what or where. The classic stem shows a left shift (increased immature bands on the differential), a marker of a brisk bacterial response. The trap is treating a high WBC as automatic infection: trauma, autoimmune flares, or post-op tissue injury raise the same markers without any pathogen, so the priority answer is to assess the source, not reflexively reach for antibiotics.

Distinguish it sharply from its neighbors. Sepsis is inflammation gone systemic and dysregulated — life-threatening organ dysfunction; the Hour-1 bundle pairs blood cultures before antibiotics with broad-spectrum antibiotics within the hour (don’t let cultures delay the drug), whereas localized inflammation is protective. Edema is a consequence of inflammation’s vascular leak, not the process itself, and hypoxia can follow when swelling compresses tissue. Mnemonic: four of the five Latin signs share an -or ending, with functio laesa the odd one out, added later.