There isn’t a specific blood test that can definitively diagnose a skin infection, as skin infections are typically diagnosed through clinical examination and sometimes additional laboratory tests. However, there are certain blood tests that may be ordered by healthcare providers to support the diagnosis of a skin infection or to assess the severity of the infection. These may include:
- Complete Blood Count (CBC): This test provides information about the number and types of cells in the blood, including white blood cells (WBCs), which are involved in the body’s immune response to infection. An elevated WBC count, particularly an increase in neutrophils (a type of WBC), may suggest the presence of an infection.
- C-reactive protein (CRP): CRP is a protein that is produced in response to inflammation in the body, including inflammation caused by infections. Elevated CRP levels in the blood can indicate the presence of an infection, including a skin infection.
- Erythrocyte sedimentation rate (ESR): This test measures how quickly red blood cells settle to the bottom of a test tube over a certain period of time. An elevated ESR can indicate inflammation in the body, which may be associated with an infection.
- Blood culture: This test involves taking a sample of blood and culturing it in a lab to identify any bacteria or fungi that may be causing an infection, including a skin infection. Blood cultures are typically ordered in cases where the infection is severe or systemic, such as in cases of cellulitis or sepsis.
It’s important to note that blood tests alone may not be sufficient for diagnosing a skin infection, and clinical evaluation by a healthcare provider, along with other diagnostic tests such as wound culture, skin biopsy, or imaging studies, may be needed for an accurate diagnosis. If you suspect you have a skin infection, it’s important to seek medical attention for proper evaluation and management.
