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Pressure ulcers cause pain, decrease quality of life, and lead
to significant morbidity and prolonged hospital stays, in part
due to complicating infection. Infected pressure ulcers are a
common problem, occurring in 4 to 6 percent
Colonization — Colonization of the pressure ulcer by
microorganisms precedes the development of infection. The
ulcer is first colonized with skin flora, which is rapidly
replaced by bacteria from the local environment and the
urogenital or gastrointestinal tracts, often from direct fecal
contamination
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High concentrations of bacteria in pressure ulcers inhibit
normal wound healing and promote infection. In one study,
delayed healing of pressure ulcers occurred when bacterial
counts were >10(5) colony forming units (CFU) per gram of
tissue
MICROBIOLOGY — The microbiology of pressure ulcers is
similar whether the ulcer is superficial or deep. Nearly all
infected pressure ulcers reveal multiple organisms when
cultures are obtained
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The predominant organisms were Enterobacter (29 percent),
staphylococci (28 percent) and Enterococcus faecalis (16
percent).
The major organisms were staphylococci (including
methicillin-resistant Staphylococcus aureus [MRSA],
methicillin-susceptible S. aureus, and coagulase-negative
staphylococci), streptococci, Proteus mirabilis, and anaerobes
Common culture techniques include quantitative swab culture,
needle aspiration, and tissue or bone biopsy.
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Aerobes that are commonly recovered include
staphylococci,enterococci, Proteus mirabilis, E. coli, and
Pseudomonas spp.
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Anaerobic; Peptostreptococcus, Bacteroides fragilis, and
Clostridiumspp. are frequently isolated from the infections
Bacteremia in this situation is usually caused by P. mirabilis,S.
aureus, or B. fragilis
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for infection control practices, a swab culture may be useful in
identifying patients colonized with MRSA or other resistant
bacteria
physicians may have only the swab culture results to guide
antibiotic selection in patients with signs of infection that are
unable or unwilling to undergo a surgical procedure for tissue
or bone biopsy.
blood culture or a culture of a deep-tissue biopsy specimen is
more clinically significant than culture from a superficial swab
specimen
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needle aspiration from below the ulcer margin to those
recovered by tissue biopsy (concordance between the aspirate
and biopsy cultures with a sensitivity of 93 percent and a
specificity of 99 percent.)
(local anesthesia should not be used because of potential
antibacterial activity)
Culturing deep tissue specimens sampled from a surgically
cleaned and debrided ulcer remains the gold standard for
wound culture
Deep infection includes ulcers complicated by cellulitis,
osteomyelitis, bacteremia, and/or sepsis, and requires
systemic antimicrobial therapy
Cellulitis
 Patients with sensory neuropathy often do not experience
pain in the setting of cellulitis.
 differentiate cellulitis from maceration of pressure ulcer
wound edges is very difficult
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Osteomyelitis
present as a poorly healing wound with or without systemic
manifestations
There were no clinical signs or symptoms that correlated with a
final diagnosis of osteomyelitis, including the presence of
fever, bone exposure, duration of the ulcer, purulent
drainage, leukocytosis, or elevated erythrocyte sedimentation
rate.
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Complications of unrecognized osteomyelitis include flap
reconstruction failure, sepsis, and bacteremia.
Bacteremia
with or without clinical signs of sepsis (eg, unexplained fever,
tachycardia, hypotension, and/or deterioration in mental
status
When pressure ulcers do cause bacteremia, they have been
associated with high mortality rate
Other complications:
 septic arthritis, endocarditis, and meningitis
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Psychosocial consequences are not often considered.
However, patients with pressure ulcers suffer pain and suffer
a loss of control over their lives. Wound care disrupts normal
activities of daily life and patients often feel stigmatized. This
results in lifestyle changes leading to social isolation,
depression and decrements in overall health-related quality of
life.The extent and magnitude of psychosocial complications
have not been well defined in the literature.
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Pressure ulcers may also pose a risk to other hospitalized
patients by serving as a reservoir for resistant organisms such
as methicillin-resistant Staphylococcus aureus, vancomycinresistant enterococci, and multiply-resistant gram negative
bacilli
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other complications — Other complications due to pressure
ulcers are rare.
Sinus tracts may develop that communicate with the deep
viscera including the bowel or bladder.
Heterotrophic calcification occurs occasionally.
The chronic inflammatory state arising from the ulcer may
result in systemic amyloidosis.
Squamous cell carcinoma occasionally develops in a pressure
ulcer and should always be considered in patients with a
nonhealing wound