Cellulitis
-
Upload
shelley-reese -
Category
Documents
-
view
34 -
download
5
description
Transcript of Cellulitis
QUESTION 1
38 yo woman is evaluated in urgent care for redness and pus that developed near a scratch on her right shin. On PE: T=37.3 C, bp 135/75, p 78, rr 14. A 3x2 cm erythematous, warm patch is present over the right shin with associated purulence/pus, but no fluctuance, drainable abscess or lymphadenopathy is present. WBC is 10k with 70% N and 30% L. She has no drug allergies.
Which of the following is the most appropriate outpatient
therapy?• A) Cephalexin (Keflex)• B) Dicloxacillin• C) Trimethoprim-sulfamethoxazole (Bactrim)• D) Amoxicillin
QUESTION 2
A 27 yo male is evaluated for redness that developed over his left forearm at the site of a mosquito bite. He is otherwise healthy and takes no medications. PE: T= 37.2 C, bp 120/70, p 68, rr 14. There is an erythematous 3x3 cm patch on the left forearm. The area is warm to the touch with no evidence of purulence, fluctuance, crepitus, or lymphadenopathy.Which of the following is the most appropriate empiric outpatient therapy?
• A) Doxycycline• B) Cephalexin (Keflex)• C) Fluconazole• D) Trimethoprim-sulfamethoxazole (Bactrim)• E) Metronidazole
ANSWERS
Answer for question 1: C, Bactrim
Answer for question 2: B, Cephalexin (Keflex)
What is the one important difference between the
two cases?
CELLULITIS
CELLULITIS
Clinical presentation: local tenderness, pain and erythema that rapidly increases. Borders are not elevated or sharply demarcated (as in erysipelas). May have patchy involvement with skip areas.
Systemic manifestations include mild fever, chills and malaise, can progress to sepsis.
CELLULITIS
Complications can include bacteremia, abscesses, overlying skin necrosis, muscle/joint/bone involvement. Risk factors: lymphedema, chronic venous stasis, trauma, skin breakdown (fungal infection), diabetes, immunosuppression, altered anatomy/surgery.Patient who are showing systemic signs (i.e., meet SIRS criteria) should be admitted for initial treatment with IV antibiotics, then transition to appropriate oral therapy.
ORGANISMS
Most common organisms: streptococci (group A β-hemolytic [GABHS] most likely) and Staphylococcus aureus. Think strep if “peau d’orange” skin changes and lymphangitis are present.Think S. aureus (and CA-MRSA, MRSA) if purulence or abscess present.Erysipelas: superficial, well-demarcated, intensely erythematous, indurated borders. GABHS.
CELLULITIS
Post-operative infections with Group A strep are uncommon but can spread rapidly and develop into bacteremia/sepsis. Can occur within 6-48 hours after surgery.
• Hypotension may be the first signs of infection prior to cellulitis.
• Thin serous discharge may be expressed from the surgical site that is gram stain positive for streptococci.
CELLULITIS
Diabetics: at risk for polymicrobial infections
including:• GPC including S. aureus, Enterococcus,
various streptococcal species, peptostreptococcus (anaerobe).
• GN aerobes: Enterobacter, Acinetobacter, and Pseudomonas.
• GN anaerobes: Bacteroides
ANTIBIOTICS IN CELLULITIS
At minimum, need empiric coverage for strep species and S. aureus.
Include a β-lactam antibiotic with activity against penicillinase-producing S. aureus (MSSA).
If not severe may treat as outpatient. • Cephalexin or dicloxacillin have good strep and MSSA
coverage.
• Clindamycin may be used for strep and CA-MRSA (know local antibiogram).
• If suspect MRSA then consider TMP-SMX or doxycycline (can add clindamycin or amoxillin if need improved strep coverage). May also consider Linezolid.
ANTIBIOTICS CONT.Inpatient antibiotic choices:
• Strep/MSSA choices: nafcillin, cefazolin, clindamycin
• CA-MRSA/MRSA: clindamycin (know antibiogram), vancomycin, daptomycin, linezolid, ceftaroline.
• Diabetics: broaden to amp-sulbactam (moderate infection), pip/tazobactam (severe) plus MRSA coverage. Remember ceftriaxone does not have anaerobic coverage.
• Septic patient: start broad, then narrow coverage as cultures return.
MRSA CELLULITIS GUIDELINES
For a cutaneous abscess incision and drainage is
the primary treatment.
When is adjunct antibiotic therapy recommend for
abscesses?• Severe or extensive (multiple sites) or rapid
progression in presence of cellulitis.• Signs of systemic illness.• Associated comorbidities or
immunosuppressed.• Extremes of age.
MRSA CELLULITIS GUIDELINES
• Abscess in area difficult to drain (face, hand and genitalia).
• Associated with septic phlebitis.• Lack of response to incision and
drainage.
MRSA CELLULITIS GUIDELINES
Treatment of purulent cellulitis:• Empiric treatment for CA-MRSA/MRSA.• Bactrim, clindamycin, doxycycline or
minocycline, linezolid.• If need MRSA and streptococcus coverage:
clindamycin; or bactrim or doxycycline with amoxicillin; or linezolid alone.
• If inpatient treat with IV antibiotics initially: vancomycin, clindamycin, linezolid, daptomycin, ceftaroline.
AJM 2010;123:942-950
Retrospective cohort study in 2005-2007 comparing bactrim
to cephalexin to clindamycin for mild to moderate cellulitis.
405 patients in study:• Excluded patients with severe cellulitis.• MRSA recovered in 72/117 positive culture specimens.• Successful treatment
• TMP-SMX 138/152 (91%) • Cephalexin 134/180 (74%)• Clindamycin 34/40 (85%)
HOW LONG TO TREAT??
IDSA guidelines: five days of treatment is a effective as a 10 day course for uncomplicated cellulitis. Based on a 2004 study in which 87 patients were treated with levofloxacin 500mg po qd x 5 days compared with 43 patients who received levofloxacin for 10 days. Complete resolution on day 14 was similar and day 28 recurrence rate was similar.
However levofloxacin has a longer ½ life than β-lactam antibiotics that are used more commonly. IDSA recommends evaluation at day 5 – if resolved can stop antibiotics. If persisting, continue to 10 days.Arch Intern Med 2004;164:1169-1674.
PROPHYLAXIS FOR RECURRENT CELLULITIS
First identify and treat predisposing conditions (edema,
obesity, eczema, venous insufficiency, fungal foot infections).
Oral penicillin 250-500 mg po bid for one year should be
considered in patients who have >3 episodes per year
despite attempts to treat or control predisposing factors.
Can continue past one year (indefinitely) if factors persist
and patient tolerating.
IDSA guidelines, 2014. Based on two studies, PATCH 1 and
PATCH 2.
SPECIAL CIRCUMSTANCES FOR CELLULITIS
Erysipelothrix rhusiopathiae (erysipeloid) – gram
positive facultative anaerobic rod. Causes an indolent
cellulitis occurring in persons who handle saltwater fish,
shellfish, poultry, meat and hides. Treat with penicillin or
cephalosporin.
Aeromonas hydrophila – gram negative rod that causes
an acute cellulitis after laceration while swimming in
fresh water. Also associated with medicinal leeches.
Treat with ciprofloxacin +/- doxycycline.
SPECIAL CIRCUMSTANCES FOR CELLULITIS
Vibrio vulnificus (curved gram negative rod) causes cellulitis, bullous lesions or necrotic ulcers after exposure to warm coastal water or exposure to drippings from raw seafood.
Infection can progress to necrosis requiring surgical debridement.
• Bacteremia with septicemia can occur after eating raw oysters, can develop associated skin findings.
• Alcoholic cirrhosis, hemochromatosis and thalassemia increase the risk of septicemia and development of necrotizing fasciitis (due to iron overload).
• Treat with doxycycline plus ceftriaxone.
OTHER
Animal or human bite: • Clean wound, check tetanus status of patient,
rabies status of animal.• Usually polymicrobial infection due to mouth
and skin flora. • Empiric antibiotic coverage with Augmentin or
unasyn. • Penicillin allergic : fluoroquinolone or
doxycycline (plus clindamycin or metronidazole for anaerobic coverage).
IMMUNOS UPPRESSED (C ANC ER PATIENT S, A ID S, TRAN SPLAN T)
Differential for skin lesions much broader in this
subset – biopsy is necessary is most cases, get early
if possible.
Need to consider infection, drug reaction/eruption,
Sweet syndrome, malignancy, leukocytoclastic
vasculitis, erythema multiforme.
QUESTION 3
40 yo male evaluated in ER for LUE skin infection. He works at
the VA, where he sustained a minor laceration 3 days ago when
trying to prevent a patient’s fall. He cleaned and bandaged the
laceration but developed purulence, surrounding tenderness, and
now with fever over last 24 hours. On exam T=38.5, bp 125/75, p
90, rr 18. An area of purulent cellulitis measuring 4x5 cm
surrounding a 1.5 cm laceration is present. No fluctuance. Rest of
exam wnl. WBC 14k, 90% neutrophils. UA nl. Radiograph of arm
only shows soft tissue swelling.
QUESTION 3 CONTINUED
Which of the following beta-lactam antibiotics is
most appropriate for treatment of this infection?• A) Meropenem• B) Oxacillin• C) Zosyn (pip/tazobactam)• D) Ceftaroline• E) Ceftriaxone
QUESTION 3 CONTINUED
Correct answer is D, ceftaroline – need MRSA
coverage due to purulence, health-care associated.
Vancomycin would have been correct if offered as a
choice.
NECROTIZING FASCIITIS
Deep tissue infection that spreads rapidly along fascial planes.Clinical features that suggest a necrotizing infection include:
• Severe constant pain, pain out of proportion to exam.• Bullae: related to occlusion of deep blood vessels that
traverse the fascia or muscles.• Skin necrosis or ecchymosis that precedes the skin necrosis.• Gas in the soft tissues.• Edema that extends beyond the margin of the erythema.• Cutaneous anesthesia.• Systemic toxicity (fever, leukocytosis, delirium, renal failure).• Rapid spread, especially concerning if on antibiotic therapy.• Subcutaneous tissues feels wooden-hard.
NECROTIZING FASCIITIS
Type I- Polymicrobial• Includes at least one anaerobic species, commonly
Bacteroides or Peptostreptococcus;• Plus one or more facultative anaerobic species such as
streptococci;• Plus members of Enterobacteriaceae (E. coli, Enterobacter,
Klebsiella, Proteus. • Associated with:
• Surgical procedures involving the bowel or penetrating abdominal trauma.
• Decubitus ulcer or a perianal abscess.• Site of injection in IVDA.• Spread from a Bartholin abscess or minor vulvovaginal
infection.
NECROTIZING FASCIITIS
Type II (aka hemolytic streptococcal gangrene): Group A streptococci are isolated either alone or with S. aureus
• Usually involves the limbs with 2/3 in the lower extremities.
• Associated with underlying disease:• DM• Arteriosclerotic vascular disease• Venous insufficiency with edema• Chronic vascular ulcer• Post varicella infection – commonly due to S.
pyogenes• Mortality is high- 50-70% in patients with
hypotension and organ failure. Lancet 1994;344:1111-5
NECROTIZING FASCIITIS
Type III- Gram negative monomicrobial• Vibrio spp
• V. damselae and V. vulnificus
• Mortality of 30-40% despite prompt diagnosis and aggressive therapy. (J of Hos Infec 2010;75:249-257)
Type IV- Fungal• Cases of candida NF very rare, mostly in immunocompromised.
• Zygomycotic NF (Mucor and Rhizopus spp) affect immunocompetent patients after severe trauma.
• Burns or trauma wounds with aspergillus or zygomycetes should be consider infected (not just colonized). (J of Hos Infec 2010;75:249-257
NECROTIZING FASCIITIS
Determinants of mortality• Retrospective study in 2005 in Taiwan. • Studied both type I and type II necrotizing fasciitis.
• 87 pts. Found increased mortality with:• Age >60• 2 comorbidities, especially DM and liver disease• Thrombocytopenia• Abnormal liver function tests• Increased BUN and Cr• Low serum albumin level
• Patients who underwent emergent debridement in <24 hours had a lower mortality than patients whose surgery was delayed (26% vs 45.9%).
• Total of 30/87 patients died in this study (34.4%).• J Micro Imm Infect 2005;38:430-435
NECROTIZING FASCIITIS
Studies• CT scan or MRI may show edema and/or gas
extending along the fascial plane. • In practice, clinical judgment is the most
important element of diagnosis.• Cultures obtained from deep tissue during
surgery are helpful.• Skin cultures usually contaminated with skin
flora.
NECROTIZING FASCIITIS
Treatment:
• Surgical intervention:• No response to antibiotic therapy.
• Profound toxicity with fever, hypotension, or advancement of skin and soft-tissue infection during antibiotic therapy.
• Local wound shows any necrosis with easy dissection along fascia by blunt instrument.
• Any soft tissue infection accompanied by gas.
• Most patients with necrotizing fasciitis should return to the OR within 24-36 hours after first debridement and daily thereafter until surgical team finds no further need for debridement.
NECROTIZING FASCIITIS
Empiric coverage: very broad• Piperacillin-tazobactam , plus vancomycin OR• Meropenem/imipenem plus vancomycin.• PCN allergy: Cefotaxime, plus metronidazole or
clindamycin, plus vancomycin.• Severe PCN allergy: clindamycin or metronidazole,
plus aminoglycoside or fluoroquinolone, plus vancomycin.
NECROTIZING FASCIITIS
Streptococci infections• PCN: most streptococci are susceptible in the
US.• Clindamycin: in vitro studies demonstrate both
toxin suppression and modulation of cytokine TNF production.
• Give both initially.
NECROTIZING FASCIITIS
IVIG – not enough evidence to recommend therapy.
HBO – hyperbaric oxygen – not enough evidence to
recommend therapy.