Clinical Profile of Patients with Urticarial Vasculitis in China: A Retrospective of 142 Cases.

BACKGROUND

Normocomplementemic urticarial vasculitis (NUV) and hypocomplementemic urticarial vasculitis (HUV) share clinical features, notably wheals, yet clear differential diagnostic criteria are lacking.

OBJECTIVE

To describe HUV and NUV features in Chinese inpatients for diagnosis.

METHODS

Retrospective study (March 2017-June 2024, China) of NUV/HUV patients. We analyzed clinical characteristics, laboratory results, and histological features, and compared drug efficacy.

RESULTS

Females constituted the majority of patients with urticarial vasculitis(UV). All patients present with wheals persisting for more than 24 hours, and 76.1% of the wheals exhibited partial or complete non-blanching. Angioedema was more common in patients with HUV than in NUV (44.4% vs 25.0%, p<0.05). Systemic involvement was observed in 61.1% of HUV and 41.2% of NUV. HUV was significantly associated with autoimmune diseases (p<0.05), decreased complement levels (C3, C4, C1q, and C1 inhibitor)(p<0.001), and elevated erythrocyte sedimentation rate (ESR) (p<0.01). A negative correlation between ESR and C3 levels was found in HUV, in contrast to a positive correlation in NUV. Direct immunofluorescence (DIF) test showing immunoreactants at the blood vessel were present in 50% of patients with HUV and 18.2% patients with NUV. Regarding treatment, 91.9% of NUV responded effectively to oral corticosteroids, whereas only 66.7% of HUV did; the remaining 33.3% of HUV required combination therapy with biologics.

CONCLUSION

Our study identified key factors associated with the occurrence of UV subtypes. For patients with recurrent wheals, complement levels, ESR, and the distribution pattern of immunofluorescence deposits can serve as basis for classifying UV subtypes and prompt earlier treatment.