A new study has determined that serum antineutrophil cytoplasmic antibody (ANCA) levels, mainly antimyeloperoxidase (anti-MPO) and antiproteinase 3 (anti-PR3), correlate with disease severity in ANCA-associated vasculitis (AAV).
The study, published in Immunology Research, found that the levels of these values did not correlate with disease outcome or vasculitis recurrence.
“As the expression of ANCA on the cell membrane is triggered by systemic or tissue-specific proinflammatory stimuli (TNF-α, IL-1β, IL-6, IL-18, GM-CSF) involving the complement system, our objective is to determine whether the levels of ANCA induced by immune system stress can be associated with the severity of the disease at diagnosis and be used to predict how the disease will progress,” the authors wrote.
AAV comprises a group of rare diseases characterized by inflammation and the destruction of small blood vessels. It is an autoimmune condition whose treatment objectives are to induce remission and prevent or slow the progression of end-organ damage.
Read more about AAV diagnosis
The research team conducted a retrospective analysis of 101 anti-MPO-positive samples and 54 anti-PR3-positive samples collected at diagnosis at a Spanish hospital. Demographic and clinical parameters were collected, including age at AAV diagnosis, date of first positive ANCA titer, symptoms, disease progression, the need for dialysis or transplantation, and death.
The results revealed a strong correlation between ANCA titers and a diagnosis of AVV, suggesting that ANCA may be positive in several conditions that mimic AAV. ANCA titers obtained at diagnosis did not predict a poor prognosis, but were useful for predicting the clinical course of the disease.
In terms of anti-MPO and ani-PR3 levels, there were significant differences between those individuals with pulmonary or renal involvement at diagnosis and ANCA titers.
The authors note that some patients have continuous disease relapses, highlighting the need to find indicators of disease progression so that treatment doses can be appropriately adjusted. They speculate that ANCA titers and circulating B cell levels could help determine maintenance therapy, such as rituximab infusions.
Reference
Renuncio-García M, Calvo-Río V, Benavides-Villanueva F, et al. ANCA detection with solid phase chemiluminescence assay: diagnostic and severity association in vasculitis. Immunol Res. Published online September 7, 2023. doi.10.1007/s12026-023-09422-z
