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Bacterial Infections
Practical Management of Skin and Skin Structure Infections where the risk of anerobic or Gram-negative pathogen involvement is
Because CA-MRSA has emerged as the most common cause of SSSIs in higher, such as the peri-rectal area, should also be considered
the US, a management algorithm should be followed in order to complicated SSSIs. Of note, MRSA has recently been identified as an
guarantee adequate treatment including surgery and anti-infective important pathogen in peri-anal sepsis.
therapy, but also to avoid unnecessary surgical intervention and exposure
to antibiotics.
34
Figure 1 provides an algorithm of how to approach One related consideration concerns the epidemiological management
patients with SSSIs. of these patients in the outpatient setting. If gross pus or drainage is
present, these patients should probably be isolated and the necessary
It is interesting to note that the relationship between surgical steps for the protection of other patients and hospital staff should be
intervention and antimicrobial therapy may be getting more complicated followed. Of note, a single patient in an emergency room or outpatient
due to the fact that β-lactams increase levels of PVL in center may be the source of the colonization of multiple other individuals
CA-MRSA and, potentially, also increase their invasiveness.
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As such, one suffering from diseases that also require antibiotic therapy. If such
very important step may be obtaining microbiological specimens from all colonization takes place, MRSA may emerge as a super-infecting
pathogen. Additionally, healthcare workers may serve as a significant
source or vector of MRSA in these settings.
If a patient presents with skin
Shortly after presentation and long before culture results return, a
and skin structure infections, the first
calculation in terms of the likely causative pathogens must be
step in management is to determine
undertaken, in particular considering whether MRSA or a complex mixed
infection is present. The main risk factor for MRSA SSSIs is local
by careful physical examination whether
endemicity, with recent prior antibiotic exposure (quinolones may be
surgical treatment or if antibiotics
particularly important) also playing a key role. Certain patient
characteristics, such as HIV, illegal drug injection, homelessness,
alone is sufficient.
crowding, and incarceration have been risk factors in some studies. Poor
socioeconomic conditions may lead to closer inter-individual contact,
poorer hygiene, and an increase in the risk for cross-infection. Pets and
patients in order to optimize antimicrobial choice. Although such an farm animals may also serve as important reservoirs for MRSA.
approach may be expensive and is not yet supported by prospective
studies, the seriousness of the problem should perhaps lead to a Finally, the intensity and duration of antimicrobial therapy must be
fundamental change in our management of it. In addition, the handling determined and are somewhat dependent on the requirement for
of patients and medical waste, and the advice and education given to hospitalization secondary to physiological disarray. In patients who are
patients about MRSA, should be re-evaluated. treated as outpatients for likely MRSA infections, return visits must be
scheduled and access to appropriate antibiotics must be assured;
If a patient presents with SSSIs, the first step in management is to optimally, a first dose of antimicrobial should be given in the emergency
determine by careful physical examination whether surgical treatment or room in order to reduce the number of pathogens as quickly as possible.
if antibiotics alone is sufficient. In certain cases, ultrasound, a computed Whereas initial studies implied that antibiotics did not matter in the
tomography (CT) scan, or magnetic resonance imaging (MRI) may be treatment of SSSIs, more recent studies have revealed different results.
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helpful in decision-making and in guiding the extent of surgical This may be due to selection bias in the initial studies. In tertiary care
debridement and drainage, as well as identifying a potential source, such centers in the US, it now appears that CA-MRSA must be covered.
as an imbedded foreign body. Classification into uncomplicated or Prophylactic mupirocin seems to have only a minor impact on MRSA
complicated SSSIs may be helpful. Uncomplicated SSSIs include cellulites, colonization and infection.
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furuncles, impetiginous lesions, and simple abscesses. These infections
can be treated by surgical incision alone without the application of The issue of compliance must be discussed with an emphasis on the
antibiotic agents or, in the case of acne, with antibiotics alone.
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Isolated seriousness of the problem, in particular transmission to others. For
(meaning a solitary area of infection) furunculosis or folliculitis should not patients with chronic MRSA infections, such as diabetic ulcers or
be included in clinical trials comparing antibiotics. osteomyelitis, this concern is particularly important and isolation or other
special considerations in the management of these infected patients may
As emphasized above, testing for MRSA should be performed. Of note, be advisable. The healthcare system, unfortunately, has not been
many patients with such simple infections will not seek help from prepared for the advent of widespread CA-MRSA.
38,39
doctors, instead self-treating infections using self-incision, topical wound
preparations, and over-the-counter antibiotics or disinfecting agents. Prevention and Infection Control Strategies—
Deeper soft-tissue infections, infected ulcers, burns, and major abscesses Have We Lost Already?
are considered complicated SSSIs and require antimicrobial therapy in The seriousness of CA-MRSA cannot be emphasized enough. The
addition to surgical intervention. In addition, patients may require testing assumption that patients would clear HA-MRSA once they left the
for significant underlying diseases such as diabetes mellitus, HIV, and hospital setting was wrong. Re-admissions and admissions of newly
malignancies. Superficial infections or abscesses in an anatomical site colonized/infected patients made hospitals, nursing homes, and care
50 US INFECTIOUS DISEASE
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