Infectious Diseases in Critical Care Medicine

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Purpura Fulminans
Purpura fulminans is an acute illness most commonly associated with meningococcemia but
also seen with pneumococcal or staphylococcal disease (129,130). It is typically characterized
by disseminated intravascular coagulation (DIC) and purpuric skin lesions. The sharply
demarcated purpuric lesions are often symmetrical, often on distal extremities, and evolve into
bullae filled with serous fluid, ultimately leading to skin necrosis. Skin changes are thought to
result from disseminated intravascular coagulation or due to protein c and s deficiency (131).
There are four primary features of this syndrome: large purpuric skin lesions, fever,
hypotension, and DIC. However, five cases associated withS. aureusstrains have been
reported from the Minneapolis-St. Paul, Minnesota metropolitan area. These strains produced
high levels of TSST-1, staphylococcal enterotoxin serotype B (SEB), or staphylococcal
enterotoxin serotype C (SEC). Only two of the five patients survived (132). Staphylococcal
purpura fulminans may be a newly emerging illness associated with superantigen production.
There are no specific guidelines for the therapeutic management of this serious manifestation
other than assuring that antistaphylococcal agents is selected with consideration of suscep-
tibility testing.


COMMUNITY-ACQUIRED METHICILLIN-RESISTANT
STAPHYLOCOCCUS AUREUS
CA-MRSA has become increasingly endemic in many parts of the world (133–135). In the mid-
1990s, MRSA began to be detected in the community in persons who did not have contact with
the health system. In a study of adult patients with acute, purulent skin and soft tissue
infections presenting to 11 university-affiliated emergency departments the overall prevalence
of MRSA were 59% (136).
The most common clinical syndrome has been skin and soft tissue infections with
abscesses and cellulitis being most frequent (Fig. 8). CA-MRSA may have evolved from
community-associated MSSA clones that possessed the genes for Panton-Valentine-leukocidin
(PVL) toxin. The organism appears somewhat unique in its characteristics by possessing the
MEC IV gene for methicillin resistance and the PVL genes encoding for a toxin presumably
responsible for necrosis. In the United States, a single clone of CA-MRSA (USA 300) has
become the most prevalent strain (137,138). Several emerging clinical syndromes have been
described with CA-MRSA including NF, septic thrombophlebitis, and pyomyositis. CA-MRSA
can produce systemic syndromes affecting the skin, such STSS, Waterhouse-Friderichsen
syndrome, and purpura fulminans (139). In a study by Miller et al., 14 patients were identified
as CA-MRSA with clinical and intraoperative findings of NF, necrotizing myositis, or


Figure 8 Right leg abscess, cultures grew MRSA (community acquired).


Severe Skin and Soft Tissue Infections in Critical Care 315

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