Gram positive bacteremia
The Infectious Disease Society of America (IDSA) recommends treating uncomplicated methicillin resistant staph aureus (MRSA) bacteremia with a 14-day course of intravenous vancomycin. Uncomplicated bacteremia is defined as having positive blood cultures for MRSA, but having no evidence of endocarditis, no implanted prostheses, negative blood cultures after 2–4 days of treatment, and signs of clinical improvement after 72 hrs.The antibiotic treatment of choice for streptococcal and enteroccal infections differs by species. However, it is important to look at the antibiotic resistance pattern for each species from the blood culture to better treat infections caused by resistant organisms. Gram negative bacteremia
The treatment of gram negative bacteremia is also highly dependent on the causative organism. Empiric antibiotic therapy should be guided by the most likely source of infection and the patients past exposure to healthcare facilities. In particular, a recent history of exposure to a healthcare setting may necessitate the need for antibiotics with pseudomonas aeruginosa coverage or broader coverage for resistant organisms. Extended generation cephalosporins such as ceftriaxone or beta lactam/beta lactamase inhibitor antibiotics such as piperacillin-tazobactam are frequently used for the treatment of gram negative bacteremia. Catheter-associated infections
For healthcare-associated bacteremia due to intravenous catheters, the IDSA has published guidelines for catheter removal. Short term catheters (in place <14 days) should be removed if bacteremia is caused by any gram negative bacteria, staph aureus, enterococci or mycobacteria.
Surgical procedures of the genitourinary tract, intestinal tract, or hepatobiliary tract can also lead to gram negative bacteremia. Pseudomonas and Enterobacter species are the most important causes of gram negative bacteremia in the ICU. Bacteremia risk factors
There are several risk factors that increase the likelihood of developing bacteremia from any type of bacteria. These include:

HIV infection
Diabetes Mellitus
Chronic hemodialysis
Solid organ transplant
Stem cell transplant
Treatment with glucocorticoids
Liver failure
Asplenia

Mechanism
Bacteremia can travel through the blood stream to distant sites in the body and cause infection (hematogenous spread). Hematogenous spread of bacteria is part of the pathophysiology of certain infections of the heart (endocarditis), structures around the brain (meningitis), and tuberculosis of the spine (Potts disease). Hematogenous spread of bacteria is responsible for many bone infections (osteomyelitis).Prosthetic cardiac implants (for example artificial heart valves) are especially vulnerable to infection from bacteremia. Prior to widespread use of vaccines, occult bacteremia was an important consideration in febrile children that appeared otherwise well. Diagnosis
Bacteremia is most commonly diagnosed by blood culture, in which a sample of blood drawn from the vein by needle puncture is allowed to incubate with a medium that promotes bacterial growth. If bacteria are present in the bloodstream at the time the sample is obtained, the bacteria will multiply and can thereby be detected.Any bacteria that incidentally find their way to the culture medium will also multiply. For example, if the skin is not adequately cleaned before needle puncture, contamination of the blood sample with normal bacteria that live on the surface of the skin can occur.