Internal Medicine
Internal medicine supplies the largest block of the Israeli licensing written examination, and its vignettes are usually short Hebrew-language scenarios with conventional-unit laboratory values. What is tested is not recall of guidelines but the chain from syndrome to prioritized differential to the single next best action.
Core rules
- Resuscitate before you investigate: airway, breathing, circulation, bedside glucose and ECG come before any CT in an unstable patient.
- Sepsis: blood cultures, then broad antibiotics within one hour; 30 mL/kg crystalloid; norepinephrine for MAP <65 mmHg; repeat lactate.
- Hyponatremia: confirm hypotonicity, check urine osmolality and urine sodium, exclude hypothyroidism and adrenal insufficiency before labelling SIADH.
- Correct sodium by no more than 8–10 mmol/L in 24 hours; faster correction risks osmotic demyelination.
- In DKA, check potassium first: if K <3.3 mmol/L, hold insulin and replace potassium.
- Anemia: start from MCV, then iron studies, B12/folate and reticulocyte count; never transfuse on a number alone.
Worked example
A 78-year-old woman on hydrochlorothiazide for three weeks presents confused. Sodium 118 mmol/L, glucose normal, urine osmolality 520 mOsm/kg, urine sodium 55 mmol/L; she is clinically euvolemic with no oedema, TSH normal. Reasoning: this is hypotonic hyponatremia. Urine osmolality above 100 means ADH is active; urine sodium above 30 in a euvolemic patient points to a thiazide-driven SIADH-like state. Stop the thiazide, restrict fluid, and if she seizes give a 3% saline bolus, then correct slowly. The trap is "she looks dry, give normal saline": in SIADH that can worsen the sodium. Other mark-losers are missing pseudohyponatremia, treating the number rather than the patient, and forgetting adrenal insufficiency.
Traps that cost marks
- Calling every confusion in the elderly a urinary infection.
- Starting an ACE inhibitor in acute kidney injury or bilateral renal artery stenosis.
- Ignoring drug-induced causes (NSAIDs, PPIs, thiazides, SSRIs).