Clinical Perspectives
A serious concern for lymphedema patients and those at risk By Dr. Mieke Flour
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Terminology, definition and causative organisms Bacterial infection of the dermis and subcutaneous layers, known as cellulitis, is potentially serious. It may spread locally and require hospital admission. In many reference books, a distinction is made between the deeper entity called ‘cellulitis’ and the more superficial ‘erysipelas’. Clinically the distinction is not always clear. Erysipelas is said to have significant lymphatic involvement. Cellulitis as erysipelas is commonly due to streptococcal infection (b-hemolytic Streptococcus pyogenes group A, C, G). When the infection is a complication of a pre-existing dermatological disease, a wound, or immunosuppression, staphylococcal (S. Aureus) or mixed infection should be considered. The likely organism will determine the choice of antibiotic treatment. Cellulitis accounts for about 2-3% of hospital admissions in the UK, and is said to occur in 20-30% of cases of chronic lymphedema.
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Clinical presentation, symptoms and diagnosis The diagnosis of cellulitis is based largely on clinical signs and symptoms. Systemic and local symptoms may precede skin changes.
Systemic symptoms may include: sudden malaise, fever, shivering or chills. There may be accompanying headache, nausea and vomiting. In severe cases systemic involvement can be expressed as tachycardia and hypotension. Locally, cellulitis often presents as an acutely red, warm, painful, swollen area.
Systemic and local symptoms may precede skin changes. Systemic symptoms may include: sudden malaise, fever, shivering or chills. There may be accompanying headache, nausea and vomiting. The edges may be sharply demarcated, and inflammation may rapidly spread peripherally within hours or days. Sometimes red streaks suggestive of lymphangitis develop, and regional lymph nodes are tender on palpation. Although it can occur at many sites, the limbs are most commonly affected, especially in the case of concomitant lymphedema.
Dr. M. Flour is a Dermatologist who was affiliated with the University Hospitals of Leuven, Belgium, until recent retirement. She has been involved in the in- and out-patient care for people suffering from skin lesions due to vascular disorders. For almost twenty years she participated in the multidisciplinary management of the diabetic foot syndrome.
Spring 2014
Studies indicate that 66% of cellulitis cases occur in the lower limbs. Laboratory tests are generally not helpful in establishing the diagnosis. Swabbing intact skin most often does not serve to identify the causative organism. Swabs from nose and throat or other natural niches may indicate carriership, but again may not identify the infectious organism. There may be indication for taking a swab if a culture can be obtained from a port of entry, blister or ulceration in the infected region. Blood tests may have limited value in diagnosis. While Erythrocyte sedimentation rate, C-reactive protein and an elevated white cell count indicate an inflammatory reaction, leukocytosis is found in only half of cases. An elevated ASO titer, or swab with culture from intact blisters may sometimes confirm a streptococcal or other causative organism. Anti-DNAse B and ASO titers are considered to
FACTS & FIGURES n 66% of cellulitis occurs in the
lower extremity n There seems to be a significant
increase of cases in the summer months n The risk of recurrent infectious episodes is said to be greater than 50% within a year following a first attack n Recurrent episodes of cellulitis may start a vicious circle of infection and worsening edema
Ly m p h e d e m a p a t h w a y s . c a 9
Photo: CanStockPhoto
Understanding Cellulitis