MRCP Part 1 Gastroenterology & Neurology 2

Question 1

A 30-year-old woman presents with a sudden severe headache she describes as 'the worst of her life', photophobia, and a normal CT head. What is the next investigation?

Accepted Answer

Lumbar puncture

Answer

A 'thunderclap' headache with negative CT requires lumbar puncture to exclude subarachnoid haemorrhage (SAH). LP should be performed at least 12 hours after onset to allow xanthochromia (bilirubin from haemolysed red cells) to develop. CT alone misses approximately 5% of SAH.

Question 2

Which pattern of inheritance does Huntington's disease follow?

Accepted Answer

Autosomal dominant

Answer

Huntington's disease is caused by a CAG trinucleotide repeat expansion in the HTT gene on chromosome 4, following autosomal dominant inheritance. Anticipation occurs — subsequent generations may be affected at an earlier age with longer repeat lengths.

Question 3

A 65-year-old man presents with resting tremor, bradykinesia, and rigidity. Dopamine transporter (DAT) imaging shows reduced uptake in the striatum. What is the diagnosis?

Accepted Answer

Parkinson's disease

Answer

Parkinson's disease is characterised by the triad of resting tremor, bradykinesia, and rigidity (plus postural instability), with reduced dopaminergic neurone activity in the substantia nigra. DAT scan (DaTSCAN) shows reduced striatal dopamine transporter uptake, distinguishing it from essential tremor.

Question 4

A 40-year-old woman has episodic, unilateral, throbbing headaches lasting 4–72 hours, associated with nausea, photophobia, and preceded by visual zigzag lines. What is the diagnosis?

Accepted Answer

Migraine with aura

Answer

Migraine with aura is characterised by reversible neurological symptoms preceding the headache (aura), including visual disturbances (scintillating scotoma, fortification spectra). The headache is unilateral, throbbing, 4–72 hours, with nausea/vomiting and photo/phonophobia. It meets ICHD-3 criteria.

Question 5

Which antibody is associated with myasthenia gravis?

Accepted Answer

Anti-AChR (acetylcholine receptor antibody)

Answer

Myasthenia gravis is an autoimmune neuromuscular junction disorder caused in approximately 85% of cases by anti-acetylcholine receptor (AChR) antibodies that block, accelerate degradation, or destroy AChR at the postsynaptic membrane. Anti-MuSK antibodies account for most seronegative cases.

MRCP Part 1 Practice Test

MRCP Part 1 Practice Test

MRCP Part 1 Gastroenterology & Neurology 2