In a post-operative patient, Staphylococcus aureus found normally on the skin can cause?

SCTIMST Staff Nurse - 2015 (Set-B)

Applied Microbiology & Infection control

Medium

Appeared in: SCTIMST Staff Nurse - 2015 (Set-B)

Explanation

Staphylococcus aureus is a common bacterium found on the skin and in the nasal passages of many healthy individuals.
During surgery, the skin's protective barrier is broken, creating a direct entry point for this bacterium into the body.
This direct inoculation into the surgical site makes S. aureus the most common cause of post-operative wound infections, also known as Surgical Site Infections (SSIs).
Signs of a wound infection include localized redness, warmth, swelling, pain, and purulent (pus) discharge, typically appearing 3-6 days after surgery.

Option A: Cold sores are caused by a virus (Herpes Simplex Virus, HSV-1), not a bacterium like S. aureus.
Option B: While S. aureus can cause pneumonia (especially hospital-acquired), the most common cause of community-acquired pneumonia is Streptococcus pneumoniae. The question links the organism to the skin, making a wound infection the most direct consequence of a surgical incision.
Option D: The most common causative agent for Urinary Tract Infections (UTIs) is Escherichia coli (E. coli), which typically originates from the gut flora.

Clinical Relevance

Nursing practice connection: Use the key finding related to Pathogenesis of post-operative wound infections to guide bedside assessment, documentation, and the next nursing action.
Preventing Surgical Site Infections (SSIs) is a major nursing responsibility and a key indicator of healthcare quality. It directly impacts patient recovery, length of hospital stay, and healthcare costs.
Nurses are responsible for meticulous sterile technique during wound care and for vigilant monitoring of the surgical site for early signs of infection using the REEDA assessment: Redness, Edema, Ecchymosis, Discharge, Approximation.
What if? If the patient was immunocompromised (e.g., diabetic, on chemotherapy), their risk for developing an SSI from S. aureus would be significantly higher, and the infection could progress more rapidly to sepsis, requiring more aggressive treatment.

How to Approach the Question

First, identify the key elements of the question: the patient is 'post-operative', the organism is 'Staphylococcus aureus', and its location is 'normally on the skin'.
Think about the direct consequence of a surgical procedure: it creates a break in the skin.
Connect the organism's normal location (skin) with the break in the skin (surgical wound). The most direct and logical outcome is an infection at that site.
Evaluate the other options. A cold sore is viral. Pneumonia is primarily a respiratory infection. A UTI is typically caused by gut bacteria. These are less direct or incorrect connections.
Therefore, a wound infection is the most probable complication in this specific scenario.

Concept Tested & Keywords

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