Prions include?

Appeared in: RRB Nsg. Superintendent-20 July 2019 (Shift-1)

Explanation

Prions are unique infectious agents composed entirely of misfolded protein material (PrPSc).
The name 'prion' is derived from 'proteinaceous infectious particle', highlighting its composition.
Unlike all other known infectious agents like bacteria or viruses, prions are devoid of any genetic material, meaning they contain neither DNA nor RNA.
They propagate by causing normally folded proteins (PrPc) in the host to misfold into the pathogenic prion form.

Visual 1: Diagram: Conversion of normal PrPc protein to the misfolded PrPSc prion protein. This visual helps illustrate the mechanism of prion propagation without genetic material.
Visual 2: Infographic: Comparison of different infectious agents (Virus, Bacterium, Viroid, Prion), highlighting their composition (protein, nucleic acids) and structure.

Clinical Relevance

Nursing practice connection: This is primarily an exam-oriented knowledge point with limited direct bedside application, so retain Composition of prions as background academic context rather than a clinical decision trigger.
Understanding that prions are proteins explains their extreme resistance to standard sterilization methods like heat, radiation, and chemical disinfectants that target nucleic acids. Special protocols (e.g., autoclaving at higher temperatures with sodium hydroxide) are required for decontamination.
This knowledge is critical in neurosurgery and pathology to prevent iatrogenic transmission of diseases like Creutzfeldt-Jakob Disease (CJD) through contaminated instruments.
What if? If a patient is suspected of having CJD, standard disinfection of surgical tools would be insufficient. The nurse must ensure that all instruments are processed according to specific prion decontamination protocols to prevent transmission to other patients.

How to Approach the Question

This is a factual recall question testing the fundamental definition of a specific biological entity.
First, identify the core term in the question: 'Prions'.
Recall the definition of a prion. The name itself, 'proteinaceous infectious particle', is a major clue to its composition.
Evaluate each option against this definition: Does it contain DNA? No. Does it contain RNA? No. Is it made of protein? Yes.
Select the option that accurately describes the composition of a prion, distinguishing it from other agents like viruses (DNA or RNA) and viroids (RNA only).

Concept Tested & Keywords

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Practise the full RRB Nsg. Superintendent-20 July 2019 (Shift-1)

Attempt every question from this paper in a timed mock, then review the full solution for each one.