How to diagnose Henoch-Schnlein Purpura ?
A diagnosis of HSP is suspected when a person has the characteristic rash and one of the following:
                
- abdominal pain  - joint pain  - antibody deposits on the skin  - hematuria or proteinuria
                
Antibody deposits on the skin can confirm the diagnosis of HSP. These deposits can be detected using a skin biopsy, a procedure that involves taking a piece of skin tissue for examination with a microscope. A skin biopsy is performed by a health care provider in a hospital with little or no sedation and local anesthetic. The skin tissue is examined in a lab by a pathologista doctor who specializes in diagnosing diseases.
                
A kidney biopsy may also be needed. A kidney biopsy is performed by a health care provider in a hospital with light sedation and local anesthetic. The health care provider uses imaging techniques such as ultrasound or a computerized tomography scan to guide the biopsy needle into the organ. The kidney tissue is examined in a lab by a pathologist. The test can confirm diagnosis and be used to determine the extent of kidney involvement, which will help guide treatment decisions.
                
Hematuria and proteinuria are detected using urinalysis, which is testing of a urine sample. The urine sample is collected in a special container in a health care providers office or commercial facility and can be tested in the same location or sent to a lab for analysis. For the test, a nurse or technician places a strip of chemically treated paper, called a dipstick, into the urine sample. Patches on the dipstick change color when blood or protein are present in urine.