Aneurysms more common in GPA than other AAV types: Study
More than 40% of aneurysms ID'd in study ruptured, researchers said
People with granulomatosis with polyangiitis (GPA) are more likely to develop an aneurysm — a bulge in a blood vessel wall that can burst or rupture — than those with other types of ANCA-associated vasculitis (AAV), according to a small study in France.
Aneurysms mainly affected medium-sized vessels, especially in the kidneys, and more than 40% ruptured, researchers observed in the study, “Characteristics of ANCA-associated vasculitis with aneurysms: Case series and review of the literature,” which was published in Autoimmunity Reviews.
AAV occurs when the immune system abnormally produces self-reactive antibodies, known as ANCAs, that cause inflammation and damage to healthy blood vessels, mainly small ones. Chronic inflammation may weaken the blood vessel wall and favor the formation of an aneurysm, which can rupture, making them important to monitor in AAV patients.
“Although some case reports or small case series have described the combination of AAV with aneurysms, this remains unusual in AAV,” wrote the researchers who collected information about the initial presentation and prognosis of people with AAV who go on to develop an aneurysm.
By searching the literature and skimming through data from the French Internal Medicine Network and the French Vasculitis Study Group database, they identified 51 AAV patients with at least one aneurysm.
A total of 36 patients were identified in the published literature, while 15 had been diagnosed at clinics across France between 1991 and 2014.
Prevalence of aneurysms in AAV types
Results showed most patients were men (71%) who were diagnosed at a median age of 55.
About two-thirds (67%) had GPA, a type of AAV associated with the formation of immune cell masses that mainly affect blood vessels in the lungs, kidneys, and upper respiratory tract.
The remaining patients had either microscopic polyangiitis (29%), the most common AAV type, which is linked mainly to kidney problems, or eosinophilic granulomatosis with polyangiitis (4%), the rarest type that’s typically limited to the lungs and gastrointestinal tract.
The median Birmingham Vasculitis Activity Score (BVAS), a measure of AAV activity and symptom severity, was 18 points. The total BVAS can range from 0 to 63 points. The higher the score, the more active the disease.
A total of 92 aneurysms were reported in the 51 patients — 21 (41%) had more than one aneurysm and 10 (20%) had more than three.
Those with more than three aneurysms were significantly more affected by dyslipidemia, or abnormal blood levels of fatty molecules, than those with fewer aneurysms (29% vs. 0%). They also had a higher rate of proteinuria (88% vs. 43%), kidney (70% vs. 32%) and liver involvement (50% vs. 7%). Proteinuria refers to the presence of protein in urine and is an indicator of kidney damage.
Nearly three-quarters (74%) of the aneurysms affected medium-sized blood vessels, especially kidney arteries (27%). A total of 14 patients (27%) showed aneurysms in large blood vessels, such as the heart’s aorta, and three (5.9%) had aneurysms in both medium and large vessels.
Over a median follow-up of two years, 22 (43%) patients had a ruptured aneurysm. In most (91%), a medium-sized blood vessel was involved.
Patients with a ruptured aneurysm had significantly more lung infiltrates — when fluid, pus, or other substances occupy the lung’s airspace — at first evaluation than those whose aneurysm didn’t burst (41% vs. 10%). They were also more commonly affected by eye symptoms (23% vs. 0%), but showed less skin (5% vs. 38%) and peripheral nerve (24% vs. 54%) involvement.
Of the 45 patients with available data at the last follow-up, 10 (22%) died, including three from a ruptured aneurysm.
“The mortality associated with aneurysmal disease is significant, particularly in the case of rupture, and specific treatment should be proposed,” the researchers wrote.
Still, 49% of the patients didn’t receive specific treatment for their aneurysms and none had a rupture during follow-up. In four of them, the aneurysms regressed with medical therapy alone that included glucocorticoids.
“There was no association between the treatments initiated and the occurrence of aneurysmal rupture,” the researchers wrote, suggesting that currently used medications may not change the course of an aneurysm in people with AAV. Further studies are needed to better understand the mechanism behind aneurysm formation in AAV and identify targeted treatments to reduce the risk of rupture and death, they said.