According to "Harrison's Principles of Internal Medicine", cellulitis is an acute inflammation of the skin characterized by pain, redness, swelling and heat. It may be due to skin flora, such as S. aureus and S. pyogenes, or a large number of other bacteria. There are many ways for bacteria to penetrate the skin through cuts, burns, insect bites and intravenous catheters. Treatment with intravenous antibiotics is tailored to the diagnosis.
Established Animal Bites
Cat and dog bites causing cellulitis are usually due to Pasteurella multocida. Primary intravenous treatment for established animal bites is 1.5 to 3.0 g of ampicillin/sulbactam every 6 hours. Alternative treatment includes 600 to 900 mg of clindamycin every 8 hours plus ciprofloxacin, 400 mg every 12 hours, or cefoxitin, 2 g every 12 hours, according to "Harrison's Principles of Internal Medicine."
Staph or Strep Cellulitis
Primary intravenous treatment for cellulitis due to Staphylococcal or Streptococcal organisms includes nafcillin or oxacillin, 2 g every four to six hours. Alternative treatment includes cefazolin, 1 to 2 g every eight hours, ampicillin/sulbactam, 1.5 to 3 g every six hours, erythromycin, 0.5 to 1 g every six hours, or clindamycin, 600 to 900 mg every eight hours, according to "Harrison's Principles of Internal Medicine."
Group B Streptococcus Cellulitis
Group B Streptococcus, also called S. agalactiae, cellulitis occurs in the elderly, diabetics and people with peripheral vascular disease, according to "Harrison's Principles of Internal Medicine." Primary intravenous treatment for cellulitis includes penicillin G, 12 million units daily. An alternative treatment is vancomycin for patients allergic to penicillin.
Pseudomonas Aeruginosa Cellulitis
P. aeruginosa causes cellulitis in immunocompromised patients, such as cancer paients who have received chemotherapy and have no neutrophils, or bacteria-fighting cells. Primary intravenous treatment for cellulitis includes an anti-pseduomonal penicillin or cephalosporin.
Aeromonas Hydrophilia
A. hydrophilia causes cellulitis in lacerations in fresh water lakes, rivers and streams, according to "Harrison's Principles of Internal Medicine." Primary intravenous treatment for cellulitis includes aminoglycosides, fluoroquinolones and third-generation cephalosporins.
Erysipelothrix Rhusiopathiae Cellulitis
E. rhusiopathiae causes cellulitis in bone renderers of swine and fishmongers. Primary intravenous treatment for cellulitis includes penicillin and other beta-lactam antibiotics, erythromycin, clindamycin and tetracycline, according to "Harrison's Principles of Internal Medicine."
References
- "Harrison's Principles of Internal Medicine;" Dennis Kasper, M.D.; 2005
