It specifically affects the dermis and subcutaneous fat. Signs and symptoms include an area of redness which increases in size over a couple of days. The borders of the area of redness are generally not sharp and the skin may be swollen. While the redness often turns white when pressure is applied this is not always the case. The area of infection is usually painful. Lymphatic vessels may occasionally be involved, and the person may have a fever and feel tired
The typical signs and symptoms of cellulitis is an area which is red, hot, and painful. The photos shown here of are of mild to moderate cases, and are not representative of earlier stages of the condition.
It is important to evaluate for co-existent abscess as this finding usually requires surgical drainage as opposed to antibiotic therapy alone. Physicians' clinical assessment for abscess may be limited, especially in cases with extensive overlying induration, but use of bedside ultrasonography performed by an experienced practitioner readily discriminates between abscess and cellulitis and may change management in up to 56% of cases.
A total of 7438 new cases of cellulitis occurred between 1 January 1997 and 31 December 2002, resulting in an overall incidence rate of 24·6/1000 person-years. Including the codes for lymphangitis, erysipelas, and necrotizing fasciitis, the overall incidence rate increased to 24·8/1000. The incidence was highest in both females and males aged 45–64 years, with females having an incidence of 34·5/1000 person-years and males having an incidence of 35·7/1000 person-years