How infection is examined
The RCPA Basic Pathological Sciences (BPS) examination is an online invigilated exam open to medical, science and dental students and graduates, as well as RCPA trainees, international medical graduates, registrars and junior doctors. It tests the general principles of pathology that underpin every discipline. Check the RCPA website for the current format, dates, fees and exemptions.
Core concepts
| Concept | What to know |
|---|---|
| Virulence | Toxins, adhesins, capsules |
| Suppurative | Neutrophils and pus: staphylococci, streptococci |
| Granulomatous | TB, fungi |
| Cytopathic | Viral inclusions: CMV, HSV |
| Necrotising | Clostridium, group A strep |
| Chronic and scarring | Hepatitis B and C |
Worked questions
Worked question · TB
What is the typical histology of tuberculosis?
- A Caseating granulomas
- B Neutrophilic abscess
- C Eosinophilic infiltrate
- D Plasma cell sheets
- E Foam cells only
Show the reasoning
Answer A. TB causes caseating granulomas with epithelioid macrophages and Langhans giant cells.
Worked question · Toxins
Which toxin causes the rash of scarlet fever?
- A Streptococcal exotoxin
- B Tetanus toxin
- C Botulinum toxin
- D Cholera toxin
- E Lipopolysaccharide endotoxin
Show the reasoning
Answer A. Streptococcal pyrogenic exotoxins (erythrogenic toxins) cause the scarlet fever rash and can act as superantigens.
High-yield facts to memorise
| Term | Key fact |
|---|---|
| Exotoxin | Secreted protein toxin, often from gram-positive bacteria |
| Endotoxin | Lipopolysaccharide of gram-negative bacteria |
| Superantigen | Non-specific T cell activation, toxic shock |
| Latency | Herpesviruses persist in neurons or lymphocytes |
| Opportunistic infection | Occurs with impaired immunity |
| Zoonosis | Infection from animals, such as Q fever |
Turn each row into a flashcard and test yourself until you can explain the mechanism, not just the label.
A 3-week revision block
| Week | Focus |
|---|---|
| 1 | Mechanisms and tissue responses |
| 2 | Bacterial and mycobacterial |
| 3 | Viral, fungal, parasitic and mixed |
Answer timed questions daily and write a one-line mechanism for every question you get wrong.
Common traps
- Mixing tissue response patterns.
- Forgetting viral inclusion types.
- Confusing toxin mechanisms.
Free sample infection questions
Questions from our Pathology (RCPA) bank. Choose your answer, then open the explanation.
Endotoxin is a component of:
- ASpores
- BFungal wall
- CGram-positive cell wall teichoic acid
- DViral capsid
- EGram-negative outer membrane
Show answer and explanation
Answer E. LPS (lipid A) from Gram-negative bacteria triggers septic shock via TLR4.
Learning point: Endotoxin: Gram-negative LPS.
HIV infects cells via binding to:
- ACD8 only
- BCD19
- CCD20
- DComplement receptor 2 (CR2)
- ECD4 and CCR5 or CXCR4
Show answer and explanation
Answer E. gp120 binds CD4 with co-receptor CCR5 or CXCR4.
Learning point: HIV: CD4 plus CCR5/CXCR4.
Pneumocystis jirovecii pneumonia is most typical when CD4 counts fall below what level?
- AIt is unrelated to CD4
- B800 cells/microlitre
- C1,500 cells/microlitre
- D200 cells/microlitre
- E50,000 cells/microlitre
Show answer and explanation
Answer D. PJP risk rises sharply with CD4 below 200 in HIV; prophylaxis with trimethoprim-sulfamethoxazole is recommended.
Learning point: PJP: CD4 below 200.
Practise more infection questions free
Every infection subtopic in our bank
The bank holds 22 infection questions across 19 subtopics. You can filter by any of them, build a custom block and track your accuracy subtopic by subtopic.
- Aspergillus1
- Buruli ulcer1
- Clostridioides difficile2
- Cryptococcus1
- Endotoxin1
- Gram stain1
- Hepatitis B serology2
- HIV1
- Infective endocarditis1
- Koilocytes1
- Malaria2
- Melioidosis1
- Pneumocystis1
- Prion disease1
- Prions1
- Q fever1
- Sepsis lab1
- TB staining1
- Viral inclusions1
Common questions
Are specific organisms tested?
Yes, by pattern and mechanism.
What is a cytopathic effect?
Visible viral damage to cells, such as inclusions or giant cells.
Which infections form granulomas?
TB, leprosy, many fungi and some others.
Sources
Clinical content is summarised from current Australian guidance at the date above. Guidelines change, so always check the latest edition.
- RCPA Basic Pathological Sciences examination
- Robbins and Kumar Basic Pathology (standard text)