MRCS Part B Revision · Surgical pathology
Hypersensitivity — MRCS Part B Surgical pathology
By Dr Richard Miller, MBChB FRCS · Reviewed
Hypersensitivity is a surgical pathology station. Two of the seventeen examined stations in the MRCS Part B OSCE are surgical pathology. The surgical pathology stations ask you to reason from a specimen, a slide, a report or a vignette to a diagnosis, and then to say what it means for the patient in front of you.
What you need to know for the Hypersensitivity station
Hypersensitvity
Hypersensitivity is an altered immunological response in which a severe and harmful reaction occurs to extrinsic antigens.
There are four types of hypersensitivity reaction:
• Type I: immediate hypersensitivity or ‘allergy’ due to overproduction of IgE on mast cells and basophils (anaphylactic or immediate)
• Type II: antibody to cell-bound antigen (cytotoxic)
• Type III: immune complex reaction
• Type IV: delayed hypersensitivity mediated by T-cells.
What are you asked at the Hypersensitivity station?
The station runs to 17 questions over nine minutes. A prompt the station repeats — against each marker on a specimen, for instance — is listed once here; the model answers are in the question bank.
- What could be going on in this scenario?
- How would you manage the patient?
- The patient is stabilised. On questioning he mentions that he had facial swelling and difficulty breathing following a course of IV penicillin when younger. What type of hypersensitivity reaction is this?
- What other types of hypersensitivity reactions do you know?
- The gentleman also has a BCG scar on his left arm. What type of hypersensitivity reaction is the tuberculin test for TB?
- You also note that the gentleman has a Rutherford-Morrison scar over his right side. What is this an indication of?
- What compatibilities should a recipient be tested for prior to receiving a transplanted kidney?
- What are the two types of organ donation that may be used?
- What are the main risks of transplanting an organ?
- What types of transplant rejection do you know?
- What is done following transplantation to avoid rejection?
- The patient mentions that he was hospitalised following a severe asthma attack one year ago. What type of hypersensitivity reaction is this?
And 4 more at this station.
How is the surgical pathology station marked in MRCS Part B?
Like the anatomy stations, a surgical pathology station is marked out of 20 with all 20 marks going to clinical knowledge and its application. The second of the two may be a microbiology station.
FAQ
What does the Hypersensitivity station ask?
It opens with "What could be going on in this scenario?" and runs to 17 questions over nine minutes. Like the anatomy stations, a surgical pathology station is marked out of 20 with all 20 marks going to clinical knowledge and its application. The second of the two may be a microbiology station.
How many pathology stations are in MRCS Part B?
Two of the seventeen examined stations. The intercollegiate blueprint titles the second one surgical pathology and/or microbiology, so infection and antimicrobial topics appear here rather than in a station of their own.
How is the pathology station marked?
Out of 20, with every mark awarded for clinical knowledge and its application. There are no communication or professionalism marks available in it.
What should I revise for surgical pathology?
The general processes the syllabus names, inflammation, healing, neoplasia and infection, applied to the specimens and reports a surgical trainee meets. Candidates most often report malignancies and their mutations, inherited cancer syndromes, and obstructive jaundice.
How many stations are in the MRCS Part B OSCE?
Seventeen examined stations of nine minutes each, with a minute to read the task before each one. Two preparation stations and at least one rest station bring the circuit to about twenty, and the exam takes about three and a half hours.
What is the pass mark for MRCS Part B?
There is no published pass mark. The cut score is set separately for Applied Knowledge and Applied Skills, for each circuit, by borderline regression. Published pass rates across the 2024/25 diets ranged from 51% to 66%.
Can I fail a station and still pass?
Yes. There is no rule about how many stations you may fail: the cut score applies to your total mark in each component, so a weak station costs the marks you lost on it and strong stations elsewhere can make them back. Applied Knowledge and Applied Skills are passed separately and must both be passed at the same sitting, so a strong anatomy performance cannot rescue a weak communication one.
Dr Richard Miller, MBChB FRCS
Station summaries are reviewed against the current intercollegiate MRCS syllabus and the published marking blueprint. Guidance changes between diets: check the royal colleges' own pages before relying on a date, a fee or a threshold.
Practise this station
The question bank carries the model answer to every question above, with the rest of the surgical pathology stations.
More surgical pathology stations