MRCP PART 1 Cheat Sheet 2026

The 30 highest-yield MRCP PART 1 facts, distilled from real exam questions. Print it, save it as a PDF, or study it here — free, no sign-up.

1. Which enzyme deficiency most commonly causes congenital adrenal hyperplasia? → 21-hydroxylase deficiency
2. A 30-year-old man presents with profuse watery diarrhoea, terminal ileum disease on colonoscopy, and perianal fistulae. What is the most likely diagnosis? → Crohn's disease
3. A patient with chronic kidney disease has a corrected calcium of 1.9 mmol/L and phosphate of 2.1 mmol/L. Which is the most likely underlying mechanism? → Reduced renal 1-alpha-hydroxylase activity
4. A patient with known asthma has a PEFR of 33% best and cannot complete sentences. What severity of asthma attack is this? → Life-threatening asthma
5. A patient with known SLE presents with a butterfly rash, arthritis, positive anti-dsDNA, and low complement levels (C3, C4). What does this combination suggest? → Active lupus nephritis
6. Which investigation is the gold standard for diagnosing chronic pancreatitis when cross-sectional imaging is equivocal? → Endoscopic ultrasound (EUS)
7. Which enzyme deficiency is responsible for acute intermittent porphyria? → Porphobilinogen deaminase
8. What is the mechanism by which montelukast acts in asthma? → Leukotriene receptor antagonism
9. A 58-year-old woman with active rheumatoid arthritis is about to start methotrexate. Which baseline investigation is most critical before initiating this drug? → Liver function tests and full blood count
10. Which pattern of inheritance does Huntington's disease follow? → Autosomal dominant
11. A patient with haemophilia A has a factor VIII level of 3%. What severity does this represent? → Moderate haemophilia A (1–5% factor VIII)
12. Which of the following pleural fluid findings are most consistent with an exudate using Light's criteria? → Pleural protein/serum protein ratio >0.5
13. In which condition would you expect to find bilateral hilar lymphadenopathy on chest X-ray with a raised serum ACE level? → Sarcoidosis
14. What is the most appropriate surveillance strategy for a patient with Barrett's oesophagus without dysplasia? → Endoscopy with quadrantic biopsies every 2-3 years
15. In disseminated intravascular coagulation (DIC), which coagulation profile would you expect? → Elevated PT, elevated APTT, reduced fibrinogen, reduced platelets
16. What is the mechanism of action of rifaximin in hepatic encephalopathy? → Minimally absorbed antibiotic that alters gut flora to reduce ammonia production
17. Which drug used for type 2 diabetes has been shown to reduce cardiovascular death and hospitalisation for heart failure in patients with established CVD? → Empagliflozin
18. A 45-year-old woman presents with jaundice, pruritus, elevated ALP, and positive anti-mitochondrial antibodies (AMA). What is the diagnosis? → Primary biliary cholangitis
19. A patient presents with petechiae, gum bleeding, and a platelet count of 8 × 10⁹/L. Blood film shows no clumping. What is the diagnosis? → Immune thrombocytopenia (ITP)
20. Which finding on ANCA testing is associated with granulomatosis with polyangiitis (Wegener's)? → c-ANCA (anti-PR3)
21. A patient develops red man syndrome during vancomycin infusion. What is the mechanism? → Direct mast cell degranulation causing histamine release, unrelated to IgE
22. Which staging system is used for chronic lymphocytic leukaemia (CLL)? → Rai or Binet staging
23. A 72-year-old man presents with a resting tremor, bradykinesia, and rigidity. Which neurotransmitter deficiency is primarily responsible? → Dopamine
24. Which cytokine is most important in the pathogenesis of septic shock? → Tumour necrosis factor alpha (TNF-alpha)
25. What is the mechanism of action of digoxin in atrial fibrillation? → Blocks sodium-potassium ATPase, increasing vagal tone and slowing AV node conduction
26. What is the most appropriate first-line treatment for a Wells score of 3 and a positive D-dimer in a patient with suspected PE? → Request CT pulmonary angiography and treat if confirmed
27. A 70-year-old woman with atrial fibrillation has a CHA2DS2-VASc score of 4. According to NICE guidelines, what is the recommended anticoagulation strategy? → Direct oral anticoagulant (DOAC)
28. Which investigation is the gold standard for diagnosing Cushing's syndrome? → Overnight 1mg dexamethasone suppression test
29. A 30-year-old man presents with erythema migrans (expanding bullseye rash) after a camping trip in the New Forest. What is the treatment of choice? → Doxycycline 100mg BD for 14–21 days
30. A patient is intubated and ventilated for ARDS. Which ventilation strategy reduces mortality? → Lung-protective ventilation (tidal volume 6 mL/kg, plateau pressure <30 cmH2O)