Laboratory Medicine and Nosocomial Infections: the Present

Nosocomial infections or hospital acquired infections (HAIs) are generally diagnosed between 2 to 4 days after a patient is admitted to a hospital, as the patient develops a fever that is not explained by an underlying illness. In elderly patients, the first signs of infection may be rapid breathing or mental confusion.

Organisms responsible for nosocomial or hospital acquired infections (HAIs) need to be identified by the clinical laboratory as quickly as possible. This enables hospital staff to treat and isolate infected patients, choose appropriate treatment, and prevent overuse of antibiotics.

Laboratory tests are conducted including complete blood counts (CBCs), especially to look for an increase in infection-fighting white blood cells (WBCs); urinalysis, to search for white cells or evidence of blood in the urinary tract; cultures of the infected area, blood, sputum, urine, or other body fluids or tissue to find the causative organism. The laboratory also reviews all procedures performed that might have led to infection.

The organisms are retested for antibiotic sensitivity so that the patient can be treated quickly and effectively. Many bacteria have become resistant to standard antibiotic treatments, especially when patients with chronic illnesses are given antibiotic therapy for long periods. If this happens, the patient is treated with a more specific antibiotic to which the organism is sensitive.

The newest tests will facilitate earlier and more appropriate antibiotic treatment of patients. They should also lead to earlier implementation of infection control interventions that help prevent the transmission of the pathogens to other patients.