From the Guidelines
IgA vasculitis typically presents with a classic tetrad of symptoms: palpable purpura, arthralgia or arthritis, abdominal pain, and renal involvement. The presentation of IgA vasculitis, also known as Henoch-Schönlein purpura (HSP), is characterized by a combination of symptoms that can vary in severity and impact different parts of the body.
Key Features of IgA Vasculitis
- Palpable purpura (non-thrombocytopenic purpuric rash) predominantly on the lower extremities and buttocks
- Arthralgia or arthritis affecting mainly the knees and ankles
- Abdominal pain often with gastrointestinal bleeding
- Renal involvement ranging from microscopic hematuria to nephritis The characteristic skin lesions appear as raised, purple, non-blanching spots that may coalesce into larger areas, as described in the context of IgA nephropathy and vasculitis management 1.
Additional Presentations and Laboratory Findings
Additional presentations may include scrotal pain and swelling in males, and less commonly, neurological symptoms such as headaches or seizures. Laboratory findings typically show elevated serum IgA levels, normal platelet counts, and urinalysis may reveal hematuria and/or proteinuria. The condition is caused by abnormal deposition of IgA immune complexes in small vessel walls, triggering inflammation and vasculitis, which is a key aspect of IgA nephropathy as discussed in the KDIGO 2021 guideline for the management of glomerular diseases 1. IgA vasculitis is more common in children but can affect adults, who generally have a worse prognosis, particularly regarding renal outcomes.
From the Research
Typical Presentation of IgA Vasculitis
The typical presentation of IgA vasculitis, also known as Henoch-Schönlein purpura (HSP), includes:
- Palpable purpuric lesions 2, 3, 4, 5
- Polyarthralgia or arthritis 2, 3, 4, 5
- Abdominal discomfort or pain, including intestinal colic and gastrointestinal bleeding 2, 3, 6, 4, 5
- Renal involvement, such as hematuria, nephritic syndrome, or nephrotic syndrome 2, 3, 6, 4, 5
Clinical Features
The clinical features of IgA vasculitis may vary, but the dominant features include:
- Round or oval and retiform palpable purpura predominantly on the lower legs 4
- Arthralgia or arthritis 4
- Gastrointestinal bleeding or pain 4
- Glomerulonephritis with mesangial IgA deposits (IgAVN) 4
- Pulmonary, cardiac, genital, and neurological involvement, although rare 4
Diagnosis
The diagnosis of IgA vasculitis is supported by the presence of: