For recurrent S. aureus abscesses, consider
a) Decolonization with twice-daily intranasal mupirocin for 5 days
b) Daily chlorhexidine washes for 5-7 days, then taper
c) Daily decontamination of personal items such as towels, sheets, and clothes.
Drug | Recommendation |
Pen G IV or pen Vk PO is probably the drug of choice for streptococci. | |
Not effective against Staphylococcus aureus, ex., for the rare isolate that remains penicillin-susceptible, but good coverage against Group A Strep. Group A Streptococcus is always sensitive to penicillin and amoxicillin. Inexpensive oral medication. | |
Good oral drug for Group A Streptococcus and Staphylococcus aureus (MSSA but not MRSA). | |
Effective against group A Streptococcus and MSSA but not MRSA. | |
Additionally, it is a suitable option for covering both group A Streptococcus and methicillin-sensitive Staphylococcus aureus in patients with mild to moderate disease that can be treated with oral antibiotics. | |
Along with minocycline, it is often considered an oral alternative to TMP/SMX for community-acquired MRSA. | |
For severe purulent or non-purulent cellulitis to cover MRSA | |
It may favor patients with previous vancomycin-associated nephropathy or at high risk for nephrotoxicity. Also, consider patients who may clear Vanc very quickly and might be challenging to achieve adequate therapeutic levels. Oral dosing makes conversion from IV vancomycin attractive. Some now favor using linezolid for severe GAS infections instead of clindamycin due to rising rates of resistance among S. pyogenes. | |
Used with severe GAS infections, such as toxic shock or necrotizing fasciitis. Rising resistance among GAS > 30% in the US warrants consideration of alternatives, such as linezolid, for inhibiting toxin production. Would not use as monotherapy for cellulitis. An additional concern is C. difficile infection. | |
Remains a usually effective agent for MRSA, with ~ 90% of isolates susceptible. Typically not a favored agent for streptococcal infection, with beta-lactams advocated by many. However, two studies have found that for uncomplicated, non-purulent cellulitis, TMP/SMX had similar outcomes to cephalexin (Palin CID 2013; Bowen OFID 2017 meta-analysis). |
Pathogen | First-Line Agent | Second-Line Agent |
Staphylococcus aureus (methicillin-sensitive) | ||
Staphylococcus aureus (methicillin-resistant) | Non-severe infections | |
Amoxicillin clavulanate, ampicillin/sulbactam | ||
Cefotaxime, ceftazidime | ||
Doxycycline | ||
Comment: This meta-analysis examined the benefits of antibiotics in managing cutaneous abscesses after incision and drainage (I&D). Four studies (n = 2,406 participants) were identified. There were 89 treatment failures (7.7%) in the antibiotic group and 150 (16.1%) in the placebo group. There was also a decreased incidence of new lesions in the antibiotic group (risk difference -10.0%, 95% CI -12.8% to -7.2%; odds ratio 0.32, 95% CI 0.23 to 0.44) and a mildly increased risk of minor adverse events (risk difference 4.4%, 95% CI 1.0% to 7.8%; odds ratio 1.29, 95% CI 1.06 to 1.58).
Comment: Excellent review article including diagnosis and treatment with some key points: 1) diagnosis is clinical but often incorrect. Up to 30% of cases are misdiagnosed. 2) Streptococci are the primary pathogens if non-purulent cellulitis presents, and 3) recurrent cellulitis is frequent, occurring in perhaps 30% primarily with risk factors such as obesity, lymphedema or tinea infections.
Comment: Foundation for recommendations presented in this module.
Comment: A meta-analysis could not find any evidence to support a difference between shorter and longer durations of therapy, although only two trials used the same drug as a comparator.
Comment: A small trial showed that regular use lowered risk by about 80% in analysis with up to three years of follow-up.
Comment: Double-blind, randomised, non-inferiority study of adults with SSTI at 33 sites in the USA randomly assigned (1:1) to receive omadacycline (450 mg orally every 24 h over the first 48 h then 300 mg orally every 24 h) or linezolid (600 mg orally every 12 h) for 7-14 days. While Omadacycline was non inferior in early clinical response (defined as survival with at least 20% reduction in lesion size 48–72 h after the first dose of study drug without rescue antibacterial therapy) and post-treatment response (defined as infection being sufficiently resolved such that further antibacterial therapy was not needed at both end of treatment and post-treatment evaluations at 7-14 days) it was associated wtih more nausea and vomiting than linezolid.
Rating: Important
Comment: Adults and children with a single skin abscess 5 cm in diameter or smaller were randomly assigned to receive oral clindamycin, TMP-SMX, or placebo in addition to incision and drainage. In patients with S. aureus infections, patients in the abx groups had a higher cure rate and were less likely to have a recurrent infection at 1 month. Adverse events were common in the abx groups.
Rating: Important
Comment: According to the literature review, cellulitis failure rates vary widely (6-37%). The author speculates that this reflects many cases that mimic cellulitis.
Comment: Comparative trial of 524 patients with cellulitis, cutaneous abscess, or both using TMP/SMX vs clindamycin x 10 days. Abscesses were drained. Outcomes of the two groups were similar (cure rates of 90% vs. 88%; P=0.8).
Comment: The letter to the editor noted that 30% of each group had abscesses that may only need drainage without antibiotics. The authors respond that this query was not addressed, so their trial could not provide an answer.
Comment: Recurrent cellulitis may strike patients, especially those with predisposing factors, in limbs or around breast tissue and elsewhere.
Comment: Review of 13 guidelines for skin infections from 9 European countries. Conditions included erysipelas, folliculitis, cellulitis, impetigo and furuncle. All recommended beta-lactam agents, mainly those with a limited spectrum. Seven also recommended topical fusidic acid. The beta-lactam recommended for adults varied, including penicillin (2), flucloxacillin (4), and oxacillin (1); the duration was typically 7-14 days, with a median of 10 days.
Comment: Literature review of patients hospitalized with cultures that were positive in 4.6% of 607 cases, of which Group A strep accounted for 65%, S. aureus for 14% and Gram-negative bacilli for 11%. The conclusion is that these results suggest that Group A streptococci are the primary cause of most cellulitis cases.
Rating: Important
Comment: The skin conditions that mimic cellulitis include stasis dermatitis, contact dermatitis, lymphedema, eosinophilic cellulitis, and papular urticaria.
Comment: Evaluation of sensitivity tests of 58 community-acquired MRSA isolates from soft tissue infections in an emergency room in Salt Lake City -- 51 (98%) were sensitive to TMP/SMX -- 50 (80%) sensitive to tetracycline -- 47 (81%) sensitive to clindamycin. Note that this sensitivity pattern is similar to that reported in many other studies over the past four years. TMP/SMX or clindamycin are usually "preferred."
Rating: Important
Comment: Evaluation of the treatment of cellulitis in 405 patients. The success rate was 91% with TMP/SMX vs. 74% (P < 0.001). Factors associated with treatment failure were: antibiotic inactive in vitro (OR=4.2) and cellulitis severity (OR=3.7). This report serves as testimony to the need for antibiotic treatment and the value of TMP/SMX for CA-MRSA infections.
Rating: Important
Comment: This report describes 179 patients with diffuse, non-culturable cellulitis, for whom serology (ALSO and DNase B) was performed, yielding a positive result in 73%. A separate analysis of 73 showed 71 (97%) responded to a β-lactam. Group A Streptococcus typically causes cellulitis without pus and yields negative cultures.
Comment: Review of 90 cases and 90 controls. The most common pathogen was Group G strep -- 26 (29%) cases. Additionally, in 7% of cases, 13% of household contacts, and no controls. Group A strep was detected in 7% of the samples. Recurrent infection in 7%.
Comment: The authors describe eight patients with A. baumannii infections associated with war wounds. The presentation was cellulitis with a "peau d’orange" appearance, characterized by vesicles that progressed to necrosis with bullae.
Rating: Important
Comment: Mayo Clinic review of cellulitis in a population-based cohort. There were 209 cases of cellulitis, and 35 (17%) recurred within 2 years. The most common findings in the cellulitis group are tibial involvement, malignancy and dermatitis. These risks correlate with the risk of recurrence.
Rating: Important
Comment: Leg erysipelas/cellulitis is common, affecting approximately 1 in 1,000 persons per year. Group A strep remains the most common, and foot intertrigo is a significant risk.
Comment: Review of recurrent erysipelas in 47 Patients. The average was 4.1 recurrences, most had cutaneous disruption (81%), usually due to intertrigo (60%). Antibiotic prophylaxis was given to 68% - no recurrences were noted in 72% at two years.
Comment: Group A Strep: lymphedema, early post-op wound infections, perianal cellulitis; Crepitant cellulitis: Clostridia and other anaerobes; Bites: Human - anaerobes, Eikenella, S. aureus, cats/dogs - Pasteurella; Diabetic foot: GNB and anaerobes; Blood cultures: Usually Group A strep.
Rating: Important
Comment: Randomized trial of linezolid vs. vancomycin for soft tissue infections involving MRSA. Clinical cure rates were 73% in both groups.
Comment: Anal colonization with Group G and possibly Group A, as well as other Beta-hemolytic streptococci, may serve as a reservoir for the pathogen in recurrent erysipelas. In recurrent cases, it may be beneficial to educate patients about this potential source of infection.
Comment: A retrospective review of 757 patients admitted with community-acquired cellulitis over 41 months shows that the yield of blood cultures is very low (2%), has a marginal impact on clinical management and is not cost-effective for most patients with cellulitis.
Comment: Placebo-controlled trial of antibiotic with or without prednisolone for erysipelas. Steroid treatment hastened the response.
Comment: A controlled trial demonstrated the benefit of prophylactic clindamycin (150 mg/d) in preventing recurrent S. aureus skin infections.
Comment: Microbiology studies in 50 patients hospitalized with cellulitis revealed a pathogen in blood in 5 (10%) cases, by needle aspirate in 5, but with a higher yield by skin punch biopsy in 10 (20%) cases; however, the latter is rarely performed.
Comment: A randomized trial comparing five versus ten days of treatment showed that uncomplicated cellulitis can be treated effectively in five days.
Cellulitis developing after an immunization (for smallpox with vaccinia!). There is spreading erythema and swelling as well as bulla.
Source: CDC/A. W. Mathies, MD
Typical cellulitis of the left leg with line drawn at time of evaluation. Despite effective antibitoics, erythema may extend somewhat in the first day or two but not reflect lack of therapeutic effect.
Source: John Campbell
Wikimedia Commons