The best way of diagnosing Lupus Erythematosus is via a thorough examination of the patient to analyze his chains of symptoms. The person qualifies for being infected by this disease if he scores positive with the four main diagnostic criteria of the disease. The first and foremost is the malar rash formed over the nasal bridge and cheeks. This rash may be painful in a few cases and can last from days to weeks. The second diagnostic criterion is the patient’s photosensitivity which seems most evident after his exposure to the sun rays. The third feature is the formation of discoid lesions on the skin. The last feature is Alopecia which is characterized by the presence of a patch of hair loss on the scalp.  

Apart from the physical examinations, patients are also subjected to various laboratory tests in order to confirm the presence of this infection in the body. The first test, complete blood count test, is done in order to check the red blood cells and white blood cells. Further, it gives the exact information on the size and number of hemoglobin in the red blood cells which helps the doctors to determine the infestation of this disease. Other tests are chest x-ray, kidney biopsy, and urinalysis.