A nurse is assessing patients in an emergency department. Which patient requires airborne precautions in addition to standard precautions?

Suspected pulmonary tuberculosis requires airborne precautions due to potential transmission via airborne droplet nuclei (

Understanding the Question

This question tests your ability to apply infection prevention and control principles by selecting the correct transmission-based precautions. Standard precautions are used for all patients, but additional precautions are required when a pathogen is known or suspected to be transmitted via a specific route, such as airborne, droplet, or contact.

Analyzing the Options

Let's evaluate each patient scenario to determine the primary mode of transmission and the necessary precautions.

Option 1: A patient with a methicillin-resistant Staphylococcus aureus (MRSA) wound infection. MRSA is a multidrug-resistant (MDR) pathogen primarily transmitted through direct or indirect contact with the infected wound or contaminated surfaces ^[2]. The additional precaution required here is Contact Precautions, not airborne.

Option 2: A patient with Clostridium difficile-associated diarrhea. C. difficile is a spore-forming bacterium transmitted via the fecal-oral route through contact with contaminated environmental surfaces or healthcare workers' hands. The spores are highly resistant to alcohol-based hand rubs. This patient requires Contact Precautions, with a strong emphasis on hand hygiene with soap and water and environmental cleaning ^[2].

Option 3: A patient with suspected pulmonary tuberculosis (TB) awaiting test results. Pulmonary TB is caused by Mycobacterium tuberculosis, which is transmitted through small droplet nuclei (≤5 microns) that can remain suspended in the air for hours and travel over long distances ^[3]. A patient with suspected active pulmonary TB must immediately be placed on Airborne Precautions in addition to standard precautions. This is a critical safety measure to protect healthcare workers (HCWs) and other patients, as HCWs are at significant risk of exposure and developing latent tuberculosis infection (LTBI) ^[1]. The patient should be placed in a negative-pressure airborne infection isolation room (AIIR), and staff must wear a fit-tested N95 respirator or powered air-purifying respirator (PAPR) upon entry [1,3].

Option 4: A patient with vancomycin-resistant enterococci (VRE) urinary tract infection. Similar to MRSA, VRE is another MDR pathogen that is spread primarily by direct or indirect contact ^[2]. The additional precaution required is Contact Precautions, particularly during handling of urine or contaminated equipment.

The Correct Answer and Clinical Rationale

The correct answer is Option 3. The decision to initiate airborne precautions is based on the pathogen's mechanism of transmission. The dental study on knowledge and practices regarding airborne isolation highlights that airborne transmission involves the inhalation of infectious particles that can remain viable in the air, which is the hallmark of M. tuberculosis transmission ^[3]. A patient-centered approach to isolation, as discussed in the review by Alp Meşe et al., requires matching the precaution type to the specific pathogen's transmission route to effectively break the chain of infection without overusing resources ^[2]. For a patient with suspected pulmonary TB, the risk of airborne transmission is high, and delays in isolation can lead to unprotected exposures for HCWs, as suggested by the study on TB exposure frequency among different occupational classifications ^[1]. The clinical severity of active pulmonary TB, which can lead to complications like acute respiratory distress syndrome (ARDS), further underscores the need for strict, immediate isolation to prevent nosocomial outbreaks . The other options describe infections that require contact precautions because the organisms are transmitted via direct or indirect contact with the patient or their immediate environment, not through the airborne route ^[2].