16-year-old female presents with hematuria and bloody diarrhea with abdominal colic

HSP is a vasculitis that is triggered by infections, medications, and other irritant exposures such as chemicals, insect bites, and even vaccinations. In most cases of HSP, resolution occurs spontaneously within 6-8 weeks without treatment and without sequelae, but fluctuations and recurrences over several months can occur. The most serious complication of HSP is persistent nephritis, which can lead to renal failure. Steroids and cytotoxic agents are sometimes used as treatments, but their efficacy is limited. Steroids relieve inflammatory symptoms of arthralgia and may prevent bowel intussusceptions, which occur infrequently, but they have little effect on nephritis or skin manifestations. Their use should be limited to patients presenting with serious gastrointestinal symptoms. HSP may occur at any age, but it is most common in children and young adults.

Migratory arthralgia and arthritis may be present, especially in the lower extremities. Hematuria due to renal vasculitis with glomerular crescents and immunoglobulin A mesangial deposits may occur.

Subsequently, symptoms develop, of which the following are the most common:

• Rash (95-100% of cases), especially involving the legs; this is the hallmark of the disease
• Abdominal pain and vomiting (35-85%)
• Joint pain (60-84%), especially involving the knees and ankles
• Subcutaneous edema (20-50%)
• Scrotal edema (2-35%)
• Bloody stools

References

Habif TP. Clinical Dermatology: A Color Guide to Diagnosis and Therapy. 5th ed. Philadelphia, PA: Mosby Elsevier; 2010.

Scheinfeld NS. Henoch-Schonlein Purpura. http://emedicine.medscape.com/article/984105-overview accessed 08/05/2015