Background: Henoch-Schönlein purpura is a type of systemic vasculitis found in children. Its prognosis is usually good; however, recurrence is relatively common. If the intestines are affected, severe complications could arise. Here, we investigated the value of fecal calprotectin in the early screening of Henoch-Schönlein purpura and as a useful factor for predicting gastrointestinal manifestations.
Methods: We retrospectively reviewed the medical records of pediatric patients who were diagnosed with Henoch-Schönlein purpura and underwent fecal calprotectin testing during the acute phase. The patients were categorized into gastrointestinal involvement and non-gastrointestinal involvement groups based on their clinical symptoms. Moreover, gastrointestinal involvement was categorized as follows: upper gastrointestinal tract involvement (up to the duodenum) and lower gastrointestinal tract involvement (from the terminal ileum).
Results: A total of 69 patients were diagnosed with Henoch-Schönlein purpura and underwent fecal calprotectin testing. Among them, 40 patients (58.0%) showed signs of gastrointestinal involvement. The gastrointestinal involvement group had higher fecal calprotectin levels (379.9 ± 399.8 vs. 77.4 ± 97.6 mg/kg, P = 0.000). There were no significant differences in the recurrence of Henoch-Schönlein purpura symptoms or gastrointestinal symptoms. The cut-off value to identify gastrointestinal involvement was 69.10 mg/kg (P < 0.01). Patients with fecal calprotectin levels of > 50 mg/kg showed more frequent gastrointestinal involvement (77.8% vs. 20.8%, P = 0.000) and more severe gastrointestinal symptoms. Significant differences in abdominal pain duration, Henoch-Schönlein purpura clinical score, and abdominal pain severity were observed (P = 0.002, P = 0.000, and P = 0.000, respectively). Additionally, fecal calprotectin levels were significantly higher in patients with lower gastrointestinal tract involvement (214.67 ± 150.5 vs. 581.8 ± 510.1 mg/kg, P = 0.008), and the cut-off value was 277.5 mg/kg (P < 0.01).
Conclusion: Fecal calprotectin testing is useful for identifying gastrointestinal involvement in pediatric Henoch-Schönlein purpura patients.
Keywords: Calprotectin; Child; Gastrointestinal tract; Henoch–Schönlein purpura.