Which of the following organisms is responsible for the development of rheumatic fever?

DSSSB Public Health Nurse - 2015

Applied Microbiology & Infection control

Easy

Appeared in: DSSSB Public Health Nurse - 2015

Explanation

Rheumatic fever is an inflammatory disease that develops as a post-infectious, non-suppurative complication of a Group A Streptococcus (GAS) infection.
The causative organism is Group A beta-hemolytic Streptococcus, also known as Streptococcus pyogenes.
It typically follows an episode of untreated or inadequately treated streptococcal pharyngitis (strep throat), not a skin infection.
The disease is caused by an autoimmune reaction where antibodies produced against the streptococcal M protein cross-react with human tissues, particularly the heart valves, joints, and brain (a process called molecular mimicry).

Option A: Streptococcus pneumoniae, or pneumococcus, is a different species of Streptococcus. It is a leading cause of bacterial pneumonia, meningitis, and otitis media, but it does not cause rheumatic fever.
Option B: Haemophilus influenzae is a bacterium that causes a variety of infections, primarily respiratory ones like sinusitis, otitis media, and pneumonia. It is not associated with the development of rheumatic fever.
Option D: Staphylococcus aureus is a common bacterium that causes a wide range of infections, most notably skin and soft tissue infections (like boils and cellulitis), food poisoning, and toxic shock syndrome. It does not cause rheumatic fever.

Clinical Relevance

Nursing practice connection: This is primarily an exam-oriented knowledge point with limited direct bedside application, so retain Causative organism of Rheumatic Fever as background academic context rather than a clinical decision trigger.
Nurses play a crucial role in preventing rheumatic fever by educating patients on the importance of seeking medical care for severe sore throats and completing the full course of prescribed antibiotics for strep throat.
Early and accurate diagnosis of streptococcal pharyngitis, often using a rapid antigen detection test (RADT) or throat culture, is essential for timely treatment and prevention of sequelae.
For patients diagnosed with acute rheumatic fever, nurses are involved in administering anti-inflammatory medications, monitoring for cardiac complications, and providing long-term education about the need for secondary antibiotic prophylaxis to prevent recurrence.

How to Approach the Question

First, identify the core of the question: it asks for the specific microorganism that causes rheumatic fever.
This is a factual recall question that links a specific disease to its causative agent.
Analyze the options provided. Notice that two options are 'Streptococcus' species, which indicates you need to differentiate between them.
Recall or deduce the common name for the precursor to rheumatic fever, which is 'strep throat'.
Connect 'strep throat' to its scientific name, Group A beta-hemolytic Streptococcus. This directly identifies the correct option.
Eliminate the other options by recalling the primary diseases they cause: Streptococcus pneumoniae causes pneumonia, Haemophilus influenzae causes respiratory infections, and Staphylococcus aureus causes skin infections.

Concept Tested & Keywords

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E6 Medicine Harrison 22e Part 1 p. 1247-1249

E6 Nelson Textbook of Pediatrics(2024) — Volume 1 p. 1710-1712