Introduction: Henoch-Schönlein purpura (HSP) is the most common form of pediatric vasculitis. The objective of this study was to determine the factors associated with the development and course of this disease.
Patients and methods: A case-control study was performed. The case group included patients with HSP followed-up at the pediatric rheumatology and nephrology units of a tertiary university hospital over a 2-year period. The control group included children followed-up at the pediatric rheumatology unit for mechanical or non-inflammatory conditions. A medical history including data on infectious conditions and previous medication was taken. A throat culture was performed and antistreptolysin 0 levels were quantified. The seroprevalence of different viruses was investigated. Subsequently, the patients were prospectively followed-up and disease manifestations were compared with reported epidemiological factors.
Results: Seventy patients and 58 controls were studied. A history of a recent upper respiratory infection (URI) and antibiotic intake were independently associated with development of HSP. Palpable purpura was present in 100 % of the patients. Gastrointestinal manifestations were recorded in 63 %, articular in 50 %, and renal in 18.6 %. Arthralgias were more frequent in girls and purpura duration was longer when disease onset occurred in spring or summer. Other factors studied were not associated with disease development or with a worse clinical course.
Conclusions: Factors associated with the development of HSP were a history of URI and antibiotic administration. Other epidemiological factors studied were not associated with either the development or the course of the disease.