Diagnostic value of nailfold capillaroscopy changes in Henoch–Schönlein purpura children with gastrointestinal or renal involvement

Abstract

Aim of the work: Capillaroscopy is known as a non-invasive, safe, and valuable diagnostic tool to assess the small vessels of the microcirculation in the nailfold. This study aimed to determine the diagnostic value of capillaroscopy in children with Henoch-Schönlein purpura (HSP) and major organ (gastrointestinal or renal) involvement which could increase the risk of complications. Patients and method: This study was conducted on 32 HSP children referred to the rheumatology ward of Children's Medical Center in Tehran, Iran, from 2019 to 2020, as well as 30 healthy controls. The vascular changes of the nailfold were assessed through capillaroscopy. Results: The mean age of the patients was 6.4 ± 2.2 years (3–11 years), and the female/male ratio was 1:1.7 (12 females and 20 males). The main finding of nail-fold capillaroscopy was abnormal morphology in 56.2 % of patients (vs. 6.7% control). A significant difference was seen between patients and control in terms of capillary morphology and architecture (p < 0.05). Abnormal capillary density and diameter tended to be more common in patients than in control (p > 0.05). Seven patients had gastrointestinal or renal involvement (21.9%). A high negative predictive value and low positive predictive value of density, architecture, and diameter of capillaries, were noted between patients with and without gastrointestinal and renal involvement. Conclusion: The role of microvascular involvement in children with HSP is emphasized. Changes in these vessels could be an image of this small vessel vasculitis to reflect major organ invovlement and thus avoid future complications of the disease.