Henoch-Schönlein purpura (HSP) is a systemic leukocytoclastic vasculitis often noted as a skin rash with palpable petechiae or purpura. The rash of HSP usually is accompanied by arthralgia, abdominal pain, and renal disease.1-3 HSP affects children at a rate of 15 cases/100,000 individuals annually4; the disease is believed to occur less frequently in adults, in whom the natural course of the disease is not as well understood. In adults, HSP can be confused with other autoimmune diseases such as systemic lupus erythematous and hypersensitivity vasculitis. We present a case of adult-onset HSP and review the literature.
Case Report
A 43-year-old Filipino man presented with a 2-day history of eruptions on his legs (Figure 1) and right arm that were mildly pruritic and burned. The lesions had been preceded by 2 weeks of severe arthralgia and myalgia. The patient noted he had experienced some low-grade fevers, and he complained of mild upper abdominal pain.
A few months prior to presentation, the patient had undergone a diagnostic workup by gastroenterology for an evaluation of abdominal pain and bright red blood from the rectum. Results of stool sampling noted the presence of white blood cells. He was evaluated with a barium enema; colonoscopy was not performed. He was diagnosed with acute gastroenteritis and prescribed levofloxacin for 7 days. During a visit to his primary care physician a few weeks prior to presentation, the patient had complained of significant arthralgia. The patient denied upper or lower respiratory tract symptoms. He also denied blood in his urine. The patient's medical history included migraines and a glucose-6-phosphate dehydrogenase deficiency. The only medication he took was sumatriptan for his migraines. The patient had no known allergies. He denied taking vitamins or herbal supplements and had no travel history or sick contacts. Results of a physical examination showed the patient had significant difficulty ambulating but otherwise was in no acute distress. His vital signs were within reference range. Multiple, nonblanching, erythematous papules and pustules were noted on both of the patient's legs and on his right arm. No truncal lesions were noted. Two 4-mm punch biopsy specimens were taken from the patient's left leg. Results of the histopathologic evaluation showed leukocytoclastic vasculitis (Figure 2). Results of direct immunofluorescence assays revealed granular staining (3+) of the superficial blood vessels focally for immunoglobulin A (IgA)(Figure 3). Results of a wound culture were negative. Laboratory examination results are listed in the Table. Results of a urinalysis revealed no protein, casts, or blood. Test results were negative for rheumatoid factor, hepatitis B and C, purified protein derivatives, extractable nuclear antigen antibodies, rapid plasma reagins, human immunodeficiency virus, cryoglobulins, antineutrophil cytoplasmic antibodies, and antinuclear antibodies; results of a throat culture were negative for β-hemolytic streptococcus. The results of a chest x-ray did not reveal abnormalities. The patient was diagnosed with HSP.
The patient was evaluated by the departments of internal medicine, rheumatology, nephrology, and gastroenterology. The patient initially was prescribed a therapeutic regimen of bed rest, acetaminophen, ranitidine, and diphenhydramine. He continued to have recurrent skin eruptions and developed more significant arthralgia and abdominal pain. The patient was given one dose of intramuscular methylprednisolone and oral prednisone. He continued to have occasional skin lesions and mild arthralgias for a few months but currently is clear and has no residual findings.
Comment
HSP predominantly affects people younger than 20 years, and half of all affected children are younger than 5 years.1 The tetrad of rash, arthralgia, abdominal pain, and renal disease can occur in any order over any time period,1-3 and all 4 symptoms do not have to be present clinically. The rash can occur anywhere on the body but usually appears symmetrically on the lower extremities as red to purple lesions. The rash typically presents with palpable petechiae or purpura but has been noted to occur with pustules, vesicles, and bullae. Additionally, the rash can be urticarial, and the Köbner phenomenon can be present. HSP can be distinguished from other autoimmune processes by skin or kidney biopsy results that show IgA deposition. If a biopsy of a skin specimen is performed, immune complexes are found almost equally in the normal-appearing skin and in the lesions of the rash.5 Serum complement levels also can be elevated in patients with HSP. Kawana and Nishiyama6 noted that increased levels of serum C5b-9 could be correlated with increased activity of HSP; however, C3, C4, and CH50 levels should not be monitored because they were not shown to be elevated consistently in HSP and thus were not reliable.6 Gastrointestinal tract lesions have been seen when there is no evidence of characteristic skin findings7-10; the lesions usually are present in the stomach, descending duodenum, and colon.7,11,12 The lesions can be raised, erythematous, or intermittently spaced.10