Henoch Schönlein Purpura - Een Diepgaande Blik op Huidziekten

Differential Diagnosis

Key differential diagnostic considerations of Henoch-Schönlein purpura are shown in Table 3. 26 , 27 These include polyarteritis nodosa, juvenile rheumatoid arthritis, acute hemorrhagic edema of infancy, Wegener granulomatosis, meningococcemia, Kawasaki disease, and thrombocytopenic purpura. 26 , 27 All causes of acute surgical abdomen are diagnostic considerations in patients with severe abdominal pain. Prominent purpuric ecchymoses in the absence of other symptoms may be mistaken for child abuse. Other causes of palpable purpura include Rocky Mountain spotted fever and bacterial endocarditis. Henoch-Schönlein purpura may occur with other forms of autoimmune disease, such as familial Mediterranean fever or inflammatory bowel disease. One study reported that 5 percent of patients with familial Mediterranean fever will get Henoch-Schönlein purpura. 28

Orchitis and scrotal swelling may occur in up to 35 percent of boys with Henoch-Schönlein purpura. 5 Severe scrotal edema may cause testicular torsion, which requires emergent surgical exploration. Fewer than 10 percent of patients with Henoch-Schönlein purpura experience myocardial infarction, pulmonary hemorrhage, or central nervous system involvement with seizures and hemorrhage (Table 4 5 , 10 , 13 , 16 ). 13 , 16

Diagnosis

There is no definitive test to diagnose Henoch-Schönlein purpura. The clinical triad of purpura, abdominal pain, and arthritis should raise concern. Palpable purpura in the absence of thrombocytopenia is most suggestive and is present in all patients. 5 Punch biopsy of the skin is useful to show the characteristic leukocytoclastic vasculitis. 5 Renal biopsy will demonstrate a membranoproliferative glomerulonephritis similar to IgA nephropathy.

In 1990, the American College of Rheumatology defined criteria for the diagnosis of Henoch-Schönlein purpura. 20 The criteria required the presence of two out of four features, and yielded a diagnostic sensitivity of 87.1 percent and specificity of 87.7 percent. 20 - 22 The criteria were: patient 20 years or younger at onset, palpable purpura (without thrombocytopenia), bowel angina (diffuse abdominal pain or diagnosis of bowel ischemia), and histologic changes showing granulocytes in small walls of arterioles and venules (leukocytoclastic vasculitis). 20 In 2006, the criteria were revised to make palpable purpura a mandatory feature, remove the age criterion, add arthritis as a criterion, and replace granulocytes in biopsy specimens with IgA deposition. 23 , 24 These criteria have been accepted by expert organizations but still await validation in prospective trials (Table 1 20 , 21 , 23 ).

• Palpable purpura without thrombocytopenia
• Patient 20 years or younger at disease onset
• Bowel angina (diffuse abdominal pain or diagnosis of bowel ischemia)
• Biopsy showing granulocytes in the walls of small arterioles or venules

• Diffuse abdominal pain
• Any biopsy showing predominant immunoglobulin A deposition
• Arthritis (acute, any joint) or arthralgia
• Renal involvement (any hematuria or proteinuria)

Imaging studies are not performed routinely in the evaluation of Henoch-Schönlein purpura. 17 Arteriography may be required to localize hemorrhage, and gastrointestinal endoscopy may be needed to evaluate gastrointestinal bleeding. 17 Abdominal ultrasonography or computed tomography may be needed to assess abdominal pain. 17 , 25 Barium enema may be used safely to diagnose and treat suspected intussusception, although the location is usually ileoileal and less amenable to nonsurgical correction by barium enema. 25

Management

Because Henoch-Schönlein purpura spontaneously resolves in 94 percent of children and 89 percent of adults, supportive treatment is the primary intervention. 5 , 22 , 29 Acetaminophen or nonsteroidal anti-inflammatory drugs (NSAIDS) may be used to alleviate arthralgia, although NSAIDS may aggravate gastrointestinal symptoms and should be avoided in patients with known renal involvement. Relative rest and elevation of affected extremities during the active phase of the illness may help prevent purpura. Patients should be advised that they may experience recurrent purpura as they increase their activity level.

Hospitalization may be required when adequate outpatient monitoring is unavailable or if dehydration, hemorrhage, or pain control require inpatient management. Nephrology referral is recommended with significant renal involvement. 29 In patients with severe renal disease, renal biopsy is needed to provide a definitive diagnosis and guide therapy. 29

Early steroid treatment is most appropriate for children with renal involvement or severe extrarenal symptoms. 30 It may also help relieve scrotal swelling. 5 Oral prednisone at 1 to 2 mg per kg daily for two weeks has been used to treat moderate to severe abdominal and joint symptoms, and to hasten the resolution of Henoch-Schönlein purpura in children. 30 A double-blind randomized trial found that early treatment with prednisone reduced abdominal and joint pain severity in children. 30 Although prednisone did not prevent renal disease, it was useful in treating renal disease after it started. 30 A meta-analysis found that corticosteroid use in children with Henoch-Schönlein purpura reduced the mean time to resolution of abdominal pain and decreased the odds of developing persistent renal disease. 31 Steroids did not affect the resolution of the purpura, and no harms were demonstrated. 31

Early aggressive therapy is recommended for children and adults with severe renal involvement. 30 - 32 Treatment options include high-dose steroids with immunosuppressants, high-dose intravenous immunoglobulin, plasmapheresis, and renal transplant. A recent trial found that cyclophosphamide (Cytoxan) was effective in patients with overt nephritis, although cyclosporine (Sandimmune) was not helpful (Table 5 5 , 16 , 30 , 31 ). 32