A study analyzing the clinical, histopathological and immunological profile of patients with cutaneous vasculitis: IgA vasculitis and IgA-negative vasculitis (2023)

Type of publication:Journal article

Author(s):Kakroo S.N.; Khan M.A.; Beg M.A.; *Kakroo B.

Citation:Journal of Pakistan Association of Dermatologists. 33(4) (pp 1562-1568), 2023. Date of Publication: October 2023.

Abstract:Background Skin is frequently involved in small-vessel vasculitis. Based on immunofluorescence studies, it can be IgA type (Henoch-Schoenlein purpura) or IgA-negative type i.e. leukocytoclastic vasculitis. Clinically, palpable purpura is the hallmark of the disease. Both subtypes can be associated with variable systemic involvement. Objective To compare the clinical, histopathological and immunological profile of patients with IgA and IgA-negative vasculitis with special reference to renal involvement. Methods Seventy-five patients presenting to the outpatient clinic of a tertiary care hospital with a clinical diagnosis of palpable purpura were enrolled in the study. All patients had a thorough clinical examination and detailed history, and results were documented on a pre-made proforma. Results On direct immunofluorescence findings, 40 patients had IgA vasculitis and 35 IgA-negative vasculitis. The mean age of presentation was 38.8 years in IgA vasculitis and 54.3 years in IgA-negative vasculitis. IgA vasculitis presented with frequent cutaneous (n=27, 67.5%, itching or pain) and systemic symptoms (n=18, 45%, abdominal and joints) seventeen (42.5%) as compared to IgA-negative subgroup (25.4% and 11.4%, respectively). Morphologically, palpable purpura was seen in both groups, but 11.4% patients in IgA-negative vasculitis group presented with ulcerated lesions. Patients of both groups had vessel wall fibrin deposition and necrosis, inflammatory infiltrate in the vessel wall, erythrocyte extravasation, unclear dust and endothelial swelling in descending frequencies. Complement 3 (C3) was the commonest immunoreactant (n=71; 94.7%) followed by fibrinogen (n=59; 78.7%) and immunoglobulin A (IgA) [n=40; 53.3%]. Abnormal urine microscopy findings were detected in (n=28; 70%) patients with IgA vasculitis and in (n=2; 5.7%) with IgA-negative vasculitis. Serum creatinine was raised in 12 (30%) patients with IgA vasculitis and 7 (20%) patients with IgA-negative vasculitis. Other laboratory tests had similar frequency in two groups. Conclusion IgA vasculitis was seen in a relatively younger age group in comparison to IgA-negative vasculitis. C3 was the commonest immunoreactant staining the blood vessel wall followed by fibrinogen and IgA. Renal involvement occurred more frequently in the IgA vasculitis.