Overview

Henoch-Schönlein Purpura (HSP), also known as IgA vasculitis, is a condition characterized by inflammation of small blood vessels, leading to bleeding into the skin, joints, intestines, and kidneys. It is the most common form of vasculitis in children but can also occur in adults. The hallmark of HSP is the presence of purplish skin rashes, typically on the lower limbs and buttocks, along with joint pain, abdominal discomfort, and, in some cases, kidney involvement. While HSP is usually self-limiting, some cases may require medical intervention to manage symptoms or prevent complications.

Causes

The exact cause of Henoch-Schönlein Purpura is not fully understood, but it is believed to result from an abnormal immune response, particularly involving the deposition of Immunoglobulin A (IgA) in blood vessels. Known triggers and risk factors include:

• Infections: Respiratory infections, especially streptococcal throat infections, are the most common triggers.
• Medications: Certain antibiotics, vaccines, or medications may initiate an immune reaction leading to HSP.
• Autoimmune responses: Abnormal immune activity can contribute to vessel inflammation.
• Genetics: A genetic predisposition may play a role, as some families report multiple cases.
• Cold weather: HSP incidence tends to be higher during winter and early spring, possibly linked to seasonal infections.

Symptoms

Henoch-Schönlein Purpura manifests through a classic group of symptoms, which may vary in intensity:

• Purpura: Raised purplish-red spots or bruises on the skin, especially on the legs and buttocks, that do not blanch when pressed.
• Joint pain and swelling: Commonly affects knees and ankles, causing temporary discomfort and limited movement.
• Abdominal pain: Cramping or colicky pain, sometimes accompanied by nausea, vomiting, or gastrointestinal bleeding.
• Kidney involvement: Blood or protein in the urine, which may be detected through testing even in the absence of visible symptoms.
• Fever: Some patients may experience mild fever during the acute phase.
• Rare symptoms: Involvement of the testicles in boys or neurological symptoms in severe cases.

Diagnosis

HSP is primarily diagnosed based on clinical presentation and supporting investigations:

• Physical examination: Doctors look for the characteristic purpura along with joint and abdominal signs.
• Urine tests: To detect kidney involvement by checking for blood or protein in urine.
• Blood tests: May show elevated inflammatory markers (ESR, CRP) or abnormal IgA levels, but no specific blood test confirms HSP.
• Skin biopsy: In uncertain cases, a biopsy of a skin lesion may be performed, typically revealing IgA deposits in small vessels.
• Imaging studies: Ultrasound may be used in patients with severe abdominal pain to assess intestinal involvement or complications.

Treatment

Most cases of Henoch-Schönlein Purpura resolve without the need for aggressive treatment. Management focuses on symptom relief and monitoring:

• Supportive care: Rest, hydration, and over-the-counter pain relievers like acetaminophen or ibuprofen help ease joint pain and fever.
• Corticosteroids: In moderate to severe cases, especially with intense abdominal pain or kidney involvement, corticosteroids like prednisone may be prescribed to reduce inflammation.
• Treatment of infections: If a triggering infection is identified, appropriate antibiotics may be used.
• Hospitalization: Required in severe cases with significant gastrointestinal bleeding, kidney issues, or other complications.
• Monitoring: Regular follow-ups with urine tests and blood pressure checks to monitor kidney function, particularly in children.

Prognosis

The prognosis for Henoch-Schönlein Purpura is generally excellent, especially in children:

• Full recovery: Most patients recover fully within a few weeks without long-term effects.
• Recurrences: Around one-third of patients experience one or more relapses, usually milder than the initial episode.
• Kidney outcomes: While mild kidney involvement is common, serious long-term kidney damage is rare but can occur in a small percentage of patients, especially adults.
• Long-term monitoring: Patients with kidney involvement may require follow-up for up to a year or longer.
• Favorable outlook: With early detection and proper care, most individuals lead healthy, normal lives after recovering from HSP.

Henoch-Schönlein Purpura is a manageable condition with a high rate of complete recovery, particularly with timely medical evaluation and appropriate care.