Source:
www.adam.com,
Zhidkov and Klechikoff - ICU (ZA), and
UPenn, Med C.
Alternative names:
gram-negative bacteremia;
gram-positive bacteremia
Definition:
A serious
infection caused by bacteria that has entered a
or body tissue that leads to the formation of
pus, or to the spread of the
bacteria in the
blood
Causes, incidence, and risk factors:
Sepsis is a result of a bacterial infection that can originate
anywhere in the
body. Common sites are the genitourinary tract, the
liver or biliary
(liver secretion) tract, the gastrointestinal tract, and the lungs. Less common sites are
intravenous
lines,
surgical wounds,
surgical drains, and sites of
skin breakdown known as decubitus ulcers or bedsores.
The infection is usually confirmed by a positive blood culture.
The infection can lead to shock, called septic
shock.
Low
blood pressure and a change in
mental status
may be early-warning signs of shock.
There has recently
been an increase in the occurance of sepsis caused by organisms that are
resistant to most standard
antibiotics.
Sepsis can be a life-threatening
situation, especially in people with a weakened
immune systems.
The risk factors associated with sepsis include:
- recent bacterial pneumonia
- meningitis
- a urinary tract infection that does not respond to antibiotics
- osteomyelitis
- bacterial peritonitis
- a recent dental procedure
- a recent endoscopy procedure
- a recent therapy with antibiotics
People whose immune systems are suppressed by therapies or by certain
diseases are at higher risk for sepsis. The incidence is 2 out of 10,000 people.
Symptoms:
Additional symptoms that may be associated with this disease:
- red skin spots
- joint pain
- hallucinations
- hypotonia
- white blood cell
count that is low or high
- blood culture
that is positive for bacteria
- blood gases that
reveal acidosis
- urine pH that
may be low
This disease may also alter the results of the following tests:
- RBC indices
- peripheral smear
- fibrin degradation
products
- cholesterol test
- blood differential
Treatment:
Hospitalization is necessary to achieve
treatment goals. Intravenous
antibiotic therapy should be initiated as soon as the
diagnosis is suspected.
The therapy is not delayed while determining the causative organism. Sometimes
more than one type of antibiotic is given while results of the blood
cultures are pending. Antibiotics can then be changed when the culture
results are available and the causative organism is known. The
source of the
infection should be identified if possible, which may mean further diagnostic
testing. Sources such as infected intravenous lines or surgical drains can be
removed, and sources such as abscesses
can be surgically drained. Supportive therapy with
oxygen and intravenous fluid
and management of complications is important for a good outcome.
Expectations (prognosis):
The
death rate can be as high as 60% for
people with severely low white blood cell counts or suppressed immune systems.
In people with no underlying disease, the death rate is about 5%.
Complications:
- septic shock
- impaired blood flow to vital organs (brain, heart, kidneys)
- disseminated
intravascular coagulation
Prevention:
Many cases are not preventable. Awareness of
risk may allow earlier detection.