Alternative Names

Skin infection – bacterial

Definition of Cellulitis

Cellulitis is a common skin infection caused by bacteria.

Causes, incidence, and risk factors

Staphylococcus and streptococcus bacteria are the most common causes of cellulitis.

Signs and tests

During a physical examination, the doctor may find:


Cellulitis treatment may require a hospital stay if:

Expectations (prognosis)

It is possible to be cured with 7 – 10 days of treatment. Cellulitis may be more severe in people with chronic diseases and those who are more prone to infection because their immune system is not working properly ().


Michael Lehrer, MD, Department of Dermatology, University of Pennsylvania Medical Center, Philadelphia, PA. Review provided by VeriMed Healthcare Network. Also reviewed by David Zieve, MD, MHA, Medical Director, A.D.A.M., Inc. – 4/17/2009

Cellulitis on the arm

ADAM Medical Encyclopedia

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