Anti-Dsg-I (Pemphigus Foliaceus) in Domlur, Bangalore

The anti-DSG-1 test is a screening test used for diagnosing an autoimmune disease called pemphigus foliaceus. This condition is characterised by the formation of itchy blisters or sores on the skin, mouth, or genitals.

Pemphigus foliaceus is a rare and relatively benign form of pemphigus. It is caused by the loss of intercellular adhesions in keratinocytes, which are located in the upper part of the epidermis. This leads to the formation of superficial blisters that appear when the skin is rubbed.

Keratinocytes are the most prominent cells making up the epidermis, constituting about 90% of the epidermal skin cells. These cells are glued to each other at unique sticky spots called desmosomes. 

In pemphigus foliaceus, the autoantibodies target and bind to the desmoglein-1 proteins, also known as the DSG-1 proteins. As a result of this action, the keratinocytes separate from each other, and the resultant replacement is a fluid—the blister. 

These blisters also rupture easily since they are formed near the surface of the skin. The rupturing can cause fluid to ooze out. Once the blisters break open, they can form sores on the skin. Gradually, these sores scale and crust over.

The anti-DSG-1 test is used to detect the presence of these DSG-1 proteins to help diagnose pemphigus foliaceus. It is a standard blood test, where the clinical lab technician draws blood from a vein in the arm and sends it for analysis in a labelled container. The subsequent results can help determine if the patient is suffering from pemphigus foliaceus or not.

The anti-DSG-1 test is a useful indirect immunofluorescence assay to confirm the diagnosis of Pdmphigus foliaceus and also, to know the improvement during and after treatment. Physicians advice to do both DsG1 and DsG3 antibodies as an initial test in order to identify overlapping of clinical types. A skin biopsy can also be done from the blister for routine HPE and Direct immunofluorescence on the tissue. 

Some of the reference values for the results of the pemphigus foliaceus diagnostic test are:

• If the results show a value of less than 20 RU/ml (relative units/millilitre), then the patient might not have pemphigus foliaceus.
• If the obtained results have a value equal to or more than 20 RU/ml, then further tests should be done to confirm the diagnosis of the disease.

In many patients, the DSG-1 antibody concentrations may be correlated with disease activity. Patients with a severe case of pemphigus foliaceus may have a high concentration of DSG-1 antibodies. 

Apollo 24|7 offers a comprehensive anti-DSG-1 test in multiple labs all over the country. A doctor might recommend this lab test if there is an emergence of fluid-filled blisters on the back, chest, and shoulders.

Although pemphigus foliaceus is not painful, it is characterised by a sharp pain or burning sensation in the area of the blisters. It is vital to get medical intervention for this condition since the resultant bacteria may leak into the bloodstream and cause sepsis.
 

Medically reviewed by Dr. Ravichandran G, Sr. Dermatologist, Apollo Hospitals Greams Road, Chennai