Cellulitis Your health care provider may make a diagnosis based on the appearance of the skin, or by marking the edges of the redness with a pen, to see if the redness extends beyond the marked border over the next several days.
Other tests that may be used include:
A CBC may show an elevated white blood cell count, and indicates a bacterial infection.
A blood culture may be performed if generalized infection is suspected.
Your health care provider may also suggest other tests to help rule out a blood clot because cellulitis in the lower leg has symptoms that may be similar to those of a clot occurring deep in the veins.
Carbunculosis To diagnose a carbuncle, your health care provider will look at your skin. The diagnosis is primarily based on what the skin looks like. A skin biopsy or a sample of pus may be taken to help make the diagnosis or determine the exact type of bacteria involved. If you have recurring infections, you may be tested for diabetes or other illnesses that weaken the immune system.
Cutaneous candidiasis Diagnosis is mainly based on the appearance of the skin, particularly if risk factors are present. A skin scraping can show typical yeast forms, suggestive of candida.