Nosocomial infections??? ...Take alert!!!

Nosocomial infections -known also as hospital-acquired infections,
hospital-associated infections, and hospital infections-are infections that are not present in the patient at the time of admission to hospital but develop during the course of the stay in hospital. There are two forms:

• Endogenous infection, self-infection, or auto-infection. The causative agent of the infection is present in the patient at the time of admission to hospital but there are no signs of infection. The infection develops during the stay in hospital as a result of the patients altered resistance.
• Cross-contamination followed by cross-infection. During the stay in hospital the patient comes into contact with new infective agents,becomes contaminated, and subsequently develops an infection.

While there is no clinically significant difference between the endogenous self-infection and the exogenous cross-infection, the distinction is important from the standpoint of epidemiology and prevention.

Healthy people are naturally contaminated. Faeces contain about 10^13 bacteria per gram, and the number of microorganisms on skin varies between 100 and 10000 per cm2. Many species of microorganisms live on mucous membranes where they form a normal flora. None of these tissues, however, is infected.

Microorganisms that penetrate the skin or the mucous membrane barrier reach subcutaneous tissue, muscles, bones, and body cavities (e.g. peritoneal cavity, pleural cavity, bladder), which are normally sterile (i.e. contain no detectable organisms). If a general or local reaction to this contamination develops, with clinical symptoms, there is an infection.