Master Internal Medicine
for SMLE

Core Concepts

Internal Medicine focuses on the diagnosis, treatment, and prevention of adult diseases, providing comprehensive care for complex and chronic conditions. Key pillars include cardiovascular health (CAD, CHF, HTN), respiratory diseases (COPD, asthma, pneumonia), metabolic disorders (diabetes, dyslipidemia, thyroid), renal function (AKI, CKD), gastrointestinal health (PUD, IBD, hepatitis), hematology (anemias, coagulopathies), rheumatology (arthritis, autoimmune diseases), infectious diseases (sepsis, common infections), and oncology (screening, management of complications). A systemic approach to patient care, emphasizing pathophysiology, evidence-based medicine, and patient safety, is paramount. Acute vs. chronic management, polypharmacy, and comorbidities are frequent considerations.

Clinical Presentation

• Chest Pain: Angina (exertional, relieved by rest/nitrates), MI (severe, crushing, radiating, associated with dyspnea/sweating), PE (sudden onset, pleuritic, dyspnea), Aortic Dissection (tearing, sudden, radiating to back).
• Dyspnea: CHF (orthopnea, PND, crackles, edema), COPD (chronic cough, wheezing, smoking history), Asthma (episodic wheezing, triggers), Pneumonia (fever, cough, sputum, pleuritic pain), Anemia (fatigue, pallor).
• Abdominal Pain: Appendicitis (periumbilical migrating to RIF), Cholecystitis (RUQ, radiating to shoulder, post-fatty meal), Pancreatitis (epigastric, radiating to back, severe), PUD (epigastric, relieved by food/antacids or worse).
• Fever of Unknown Origin (FUO): Prolonged fever >3 weeks, no obvious source despite thorough investigation (consider infection, malignancy, autoimmune).
• Polyuria/Polydipsia: Diabetes Mellitus (T1DM vs. T2DM), Diabetes Insipidus.
• Weight Loss (unexplained): Malignancy, Hyperthyroidism, Chronic Infection (TB), uncontrolled Diabetes.
• Edema: CHF (bilateral, pitting, dependent), CKD (periorbital, generalized), Liver Cirrhosis (ascites, peripheral), DVT (unilateral leg swelling, pain).
• Joint Pain/Swelling: Rheumatoid Arthritis (symmetric, small joints, morning stiffness), Osteoarthritis (asymmetric, weight-bearing joints, improves with rest), Gout (acute, monoarticular, hyperuricemia).

Diagnosis (Gold Standard)

Acute Myocardial Infarction: ECG changes (ST elevation/depression, T-wave inversion) and serial elevated cardiac troponins. Congestive Heart Failure: Echocardiography (ejection fraction) and elevated BNP/NT-proBNP. COPD: Post-bronchodilator spirometry (FEV1/FVC ratio < 0.7 confirms airflow limitation). Asthma: Spirometry with significant reversibility (≥12% and 200mL increase in FEV1) after bronchodilator. Diabetes Mellitus: HbA1c ≥6.5%, Fasting Plasma Glucose ≥126 mg/dL, or Oral Glucose Tolerance Test (2-hour PG ≥200 mg/dL). Chronic Kidney Disease: Sustained decrease in eGFR <60 mL/min/1.73m2 for ≥3 months, often with albuminuria (ACR ≥30 mg/g). Pulmonary Embolism: CT Pulmonary Angiography (CTPA). Deep Vein Thrombosis: Duplex Ultrasonography of leg veins. Peptic Ulcer Disease: Upper Endoscopy with biopsy for H. pylori. Anemia: Complete Blood Count (CBC) with peripheral smear, followed by iron studies, B12/folate levels as indicated.

Management (First Line)

Acute MI: Immediate Aspirin, P2Y12 inhibitor (e.g., clopidogrel), nitrates, beta-blockers, statins; prompt reperfusion therapy (Percutaneous Coronary Intervention or thrombolysis) is critical. Chronic Heart Failure (HFrEF): ACE inhibitor/ARB, beta-blocker, mineralocorticoid receptor antagonist (MRA), and SGLT2 inhibitor. COPD: Short-acting bronchodilators (SABA/SAMA) for symptom relief, long-acting bronchodilators (LABA/LAMA) for maintenance based on severity, often in combination. Asthma: Short-acting beta-agonists (SABA) for rescue, inhaled corticosteroids (ICS) as controller therapy, stepwise approach. Type 2 Diabetes Mellitus: Lifestyle modification (diet, exercise) and Metformin as first-line pharmacotherapy. Hypertension: Lifestyle changes; Thiazide diuretics, ACE inhibitors/ARBs, Calcium Channel Blockers as first-line agents depending on patient profile and comorbidities. Sepsis: Early recognition, rapid broad-spectrum IV antibiotics, aggressive fluid resuscitation, and vasopressors if refractory shock. DVT/PE: Anticoagulation (e.g., LMWH followed by oral anticoagulant like DOAC or Warfarin). H. pylori-positive PUD: Triple or quadruple therapy (PPI + 2-3 antibiotics).

Exam Red Flags