Infections
Laboratory tests are often required to diagnose infections caused by bacteria, fungi, viruses and parasites.
If a bacterial or viral infection is suspected, a so-called skin swab is usually taken with a cotton swab. A culture or PCR is performed in the laboratory. The result is usually available after 1-2 days. Bacteria or viruses that are recognized in the blood by the immune system can also be diagnosed with a blood test (serology). Urine tests are carried out if a bacterial infection of the urinary tract is suspected.
If a fungal infection is suspected, skin flakes, nail material or hair are examined. A fungal infection can often be diagnosed or ruled out in the direct preparation, which is carried out in the practice. To determine which fungus is involved, a culture is necessary, which takes 4-6 weeks.
Infections caused by parasites can be examined in a direct preparation, by means of stool culture or in the blood, depending on the pathogen.
Deficiency states
If symptoms such as itching, hair loss, brittle nails or mouth corner rhagades persist for a long time, it is important to exclude a deficiency of vitamins and trace elements (such as iron or zinc).
Diseases of organ systems
Many diseases of the organ systems, such as liver, kidney, thyroid or blood diseases, present themselves with symptoms on the skin, hair and nails. As the diagnosis cannot usually be made by appearance alone, blood tests may be necessary.
