How is Henoch-Schönlein purpura diagnosed?

Henoch-Schönlein purpura (HSP) is a type of vasculitis, which is an inflammation of the blood vessels. It primarily affects small blood vessels in the skin, intestines, kidneys, and joints. Diagnosing HSP involves a combination of clinical evaluation, medical history, physical examination, and laboratory tests.

Medical History: The first step in diagnosing HSP is taking a detailed medical history. The healthcare provider will ask about the patient's symptoms, their duration, and any previous medical conditions or medications. This information helps in ruling out other possible causes of the symptoms.

Physical Examination: A thorough physical examination is conducted to assess the patient's overall health and look for specific signs of HSP. The characteristic symptom of HSP is a rash called purpura, which appears as small, reddish-purple spots on the skin. The rash is typically found on the lower legs and buttocks but can also occur on other parts of the body. The healthcare provider will also check for joint pain, swelling, abdominal tenderness, and kidney-related symptoms.

Laboratory Tests: Several laboratory tests are performed to support the diagnosis of HSP and evaluate its severity. These tests include:

• Complete Blood Count (CBC): This test measures the levels of different blood cells. In HSP, an increased number of white blood cells and platelets may be observed.


• Urinalysis: A urine sample is analyzed to check for the presence of blood, protein, or other abnormalities. HSP can cause kidney inflammation, leading to blood and protein in the urine.


• Blood Chemistry: Various blood chemistry tests are conducted to assess kidney function, liver function, and overall health. Abnormalities in these tests may indicate organ involvement in HSP.


• Immunoglobulin A (IgA) Levels: HSP is associated with increased levels of IgA, a type of antibody, in the blood. Measuring IgA levels can help support the diagnosis.


• Kidney Biopsy: In some cases, a kidney biopsy may be performed to confirm the diagnosis and assess the severity of kidney involvement. A small sample of kidney tissue is examined under a microscope to look for characteristic changes seen in HSP.

Other Diagnostic Considerations: It is important to differentiate HSP from other conditions with similar symptoms. These may include allergic reactions, other types of vasculitis, and certain infections. Additional tests, such as skin biopsies or imaging studies, may be required to rule out these conditions.

Consultation with Specialists: Depending on the severity and specific organ involvement, consultation with specialists such as rheumatologists, nephrologists, or dermatologists may be necessary to confirm the diagnosis and guide further management.

Overall, diagnosing Henoch-Schönlein purpura involves a comprehensive approach that combines medical history, physical examination, and laboratory tests. Prompt and accurate diagnosis is crucial for initiating appropriate treatment and preventing complications.