Transcript A few ID pearls

A few ID pearls
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A 37-year-old man presents for the evaluation of
localized swelling and tenderness of the left leg
just below the knee. He suspects this lesion
developed after a spider bite, although he did
not see a spider. Examination of the leg reveals
an area of erythema and warmth measuring
approximately 5 by 7 cm. At the center of the
lesion is a fluctuant area measuring
approximately 2 by 2 cm, overlaid by a small
area of necrotic skin. The man's temperature is
38.3°C. The pulse rate is 115 beats per minute.
The blood pressure is 116/78 mm Hg. How
should this patient be evaluated and treated?
Risk Factors for MRSA
Recent ABX use.
 Recent hospitalization
 HD
 IVDU
 DM
 Previous MRSA infection/colonization
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Initial treatment
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Best initial treatment
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I&D of “small” abscesses
Small = less than 5cm in length
Randomized trial of 166 patients with uncomplicated
skin abscesses at risk for community-associated
MRSA (CA-MRSA) who were managed with
cephalexin or placebo following incision and drainage
of skin and soft tissue abscesses.
The cure rates were similar in the two groups (84 and
90 percent, respectively).
MRSA Skin and Soft Tissue
Infections
Patients with larger areas of infection
and/or systemic signs of infection should
be managed with antimicrobial therapy.
 Empiric therapy
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Beta-lactam antibiotics are no longer reliable
empiric therapy for skin and soft tissue
infections.
Local incidence rate = 56%
Options for therapy
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Clindamycin
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TMP/SMX
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Use caution if local resistance rate is 10-15%
Use based on observational study only
Tetracyclines (Doxy or Mino)
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Also from observational/retrospective data
Linezolid
 Rifampin
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MRSA Skin and Soft Tissue
Infections
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Bottom line
I&D is essential for abscesses
 Pay attention to local resistance patterns
 Beta-lactams are no longer viable first choices
for empiric treatment of at-risk patients
 TMP/SMX is good parenteral option but
evidence is observational.
 Linezolid second choice for those that cannot
tolerate first choice meds.
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A 37 year old man comes to the clinic with
a 7-day history of coarse productive
cough, fatigue/malaise, sore throat, nasal
congestion and runny nose, and mild
shortness of breath. His medical history is
unremarkable. His vital signs include a
temp of 99.1, RR of 18 and BP of 125/78.
Examination reveals slightly erythematous
oropharynx and very faint wheezes on
chest exam but is otherwise
unremarkable. What is the most likely
diagnosis and treatment?
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A 37 year old man comes to the clinic with a 7day history of coarse productive cough,
fatigue/malaise, sore throat, nasal congestion
and runny nose, and mild shortness of breath.
His medical history includes poorly controlled
diabetes, HTN, CAD and childhood asthma. His
vital signs include a temp of 99.1, RR of 18 and
BP of 125/78. Examination reveals slightly
erythematous oropharynx and very faint
wheezes on chest exam. There are multiple
small pustular skin lesions over his trunk and
legs which he says were diagnosed as “staph”
by a previous physician. What is the most likely
diagnosis and treatment?
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A 37 year old man comes to the clinic with a 7day history of coarse productive cough,
fatigue/malaise, sore throat, nasal congestion
and runny nose, and mild shortness of breath.
His medical history includes HIV/AIDS, chronic
diarrhea, and medical noncompliance. His vital
signs include a temp of 99.1, RR of 18 and BP of
125/78. Examination reveals slightly
erythematous oropharynx and very faint
wheezes on chest exam but is otherwise
unremarkable. What is the most likely diagnosis
and treatment?
Epidemiology
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Usual causes of AB:
Influenza A/B
 Parainfluenza
 Coronavirus
 Rhinovirus
 RSV
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Stats
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How many patients diagnosed with acute
bronchitis are given antibiotics?
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60-70%
S pneumo, H flu, S aureus, M cat
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“There is no convincing evidence to
support the concept of "acute bacterial
bronchitis" caused by these pathogens in
adults, with the exception of patients with
airway violations such as tracheostomy or
endotracheal intubation, or those with
exacerbations of chronic bronchitis.”
Acute Bronchitis
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“Routine antibiotic treatment of
uncomplicated acute bronchitis is not
recommended. If pertussis infection is
suspected (an unusual circumstance), a
diagnostic test should be performed and
antimicrobial therapy initiated.”
Acute Bronchitis Diagnosis
Productive cough as the essential
symptom
 Concurrent URI symptoms
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Rhinitis, sore throat, hoarseness
Fever is unusual sign and may suggest
pneumonia or influenza
AB vs pneumonia
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When to order a CXR?
Abnormal VS (HR>100, RR>24, Temp>38C)
 Rales or signs of consolidation on exam
 Advanced age (>75 years)
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Duration of cough
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What if cough is present for 2 weeks?
Selected studies have recovered pertussis in up
to 10% to 20% of patients with cough lasting
longer than 2 to 3 weeks.
Clinicians should limit suspicion and treatment of
adult pertussis to adults with a high probability of
exposure to pertussis—for example, during
documented outbreaks.
Pertussis may be suspected regardless of
immunization history.
Treatment of AB
NSAIDs, Tylenol, nasal decongestants
 Strong patient-physician relationship and
good communication
 Reassurance
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Evidence against ABX for AB
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A meta-analysis of 9 studies:
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5 of 9 showed no benefit of either doxycycline or
erythromycin
2 showed slight clinical differences in patients treated
with erythromycin or TMP/SMX
2 showed superiority of albuterol to erythromycin
A second meta-analysis showed a 0.6 day
reduction in cough duration.
Another study showed Azithromycin and Vitamin
C were equivalent.
Patient information
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Because the prevailing thought among
many patients is that “antibiotics will treat
my cough”, patient information/hand-outs
are available to provide further
reassurance that they are being treated
appropriately and in line with current
recommendations.
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A 57 year old man with cirrhosis is ready
to go home after an ICU admission and
treatment of acute variceal hemorrhage.
He has never had a GIB before. Besides
the usual medications aimed at preventing
recurrent GI bleeding, should he take any
other preventative medications?
Prophylaxis for SBP
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Risk factors have been identified
AF protein concentration < 1
 Variceal hemorrhage
 Prior episode of SBP
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Most flora originate in the gut
 Theory: Intestinal decontamination can
reduce SBP incidence in at risk patients.
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Does prophylaxis work?
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Meta-analysis of 13 RCTs (hospitalized patients
with cirrhosis with risk factors for infection)
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Significant mortality benefit
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Significant reduction in SBP development
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RR 0.70, CI 0.56-0.89
RR 0.39, CI 0.32-0.48
Antibiotic prophylaxis in cirrhotic patients with
gastrointestinal bleeding was studied via
systematic review.
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Significantly reduced SBP development, bacteremia
and death.
Regimens
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Single weekly Cipro vs placebo
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3.6 versus 22 percent
Bactrim DS 1 tab daily 5 days/week
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3 versus 27 percent
Continuous oral Cipro (reduced mortality
and incidence of SBP at 12 months)
 Continous TMP/SMX 1 tab daily
 Inpatient-only use of norfloxacin with
discontinuation at time of discharge.
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Recommendations
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Those with gastrointestinal bleeding
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Continuous quinolone or TMP/SMX in those who
have had one or more episodes of SBP
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Cefotaxime IV until taking PO then switch to
Norfloxacin PO x 7 days total.
Switch antibiotics if develops SBP on this regimen
Short-term norfloxacin or TMP/SMX (in-patient
only) in those with cirrhosis and AF protein
<1g/dl hospitalized for another reason.