Pathophysiology
Clinical meaning
Differential diagnosis is the systematic process of distinguishing between diseases or conditions that share similar clinical features. It is the hallmark of advanced practice nursing and requires integrating knowledge of pathophysiology, epidemiology, clinical presentation patterns, and diagnostic testing. The Diagnostic Reasoning Process: 1. Pattern Recognition (System 1 Thinking): Rapid, intuitive recognition based on experience. 'This looks like pneumonia.' Fast but prone to cognitive bias. 2. Analytical Reasoning (System 2 Thinking): Deliberate, systematic hypothesis testing. Generate → Test → Refine. Slower but more accurate for complex or atypical presentations. 3. Dual Process Model: Expert clinicians use BOTH: pattern recognition triggers initial hypotheses, then analytical reasoning tests and refines them. Steps in Differential Diagnosis: 1. Gather complete clinical data (H&P) 2. Identify the problem representation: Summarize the case in one sentence. Example: '65-year-old male smoker with acute-onset pleuritic chest pain, dyspnea, and unilateral leg swelling.' 3. Generate an initial differential list (broad) 4. Apply illness scripts: Compare the patient's presentation against known disease patterns 5. Prioritize by probability AND severity (cannot-miss diagnoses) 6. Select and interpret diagnostic tests (understand pre-test probability, sensitivity,...