Urinalysis, i.e. urine examination, generally includes routine urinalysis, detection of organic components in urine (e.g. urine red blood cells, white blood cells, etc.), quantitative determination of protein components, urine enzyme assay, etc. In the case of purpura, the values need to be checked according to the cause of the disease. Usually the two main tests are urine protein and occult blood, while urine specific gravity and osmolality reflect the severity of symptoms.
In short, the tests are complex to check and it is advisable to consult your doctor for clarification.