Question

Difference between exogenous and endogenous infection in tabular form

Answer 1

In the case of endogenous infections, we become infected with our own bacteria, our own microflora. This might happen if a barrier between sterile and non-sterile tissues is broken, such as with a bowel perforation. A patient with a compromised immune system, such as after chemotherapy, may become sick from a bacteria already present in his/her body that grows unchecked. A dormant pathogen might also become reactivated and infect the host, such as in the case of tuberculosis.

From an infection prevention standpoint, avoiding endogenous infections focuses on careful protocols during invasive procedures, antibiotic stewardship, and working to keep the patient's immune system working as well as possible.

Exogenous Infections | exo- "outside"; -genous "born from"
Exogenous infections, in contrast, involve a pathogen entering a patient's body from his/her environment. These pathogens can be introduced through a contaminated device, healthcare worker, surface, or other vector. Patients with open incisions, indewelling devices, and compromised immune systems are especially at risk for exogenous infections.

Eliminating exogenous infections focuses almost entirely on reducing the bioburden in the patient's environment. If the reservoirs for pathogens can be reduced, the opportunities for cross-contamination diminish. Everyone agrees that hand hygiene is the single most important way to reduce transmission of pathogens to vulnerable patients. Other interventions focus on environmental decontamination of surfaces and other fomites, including daily cleaning, UV light, and self-sanitizing surfaces.