A new score to quantify GCA inflammation? Save

The treatment paradigm for Giant Cell Arteritis (GCA) has been a binary approach to the presence or absence of vasculitis. When GCA is present, we institute high doses of glucocorticoids for treatment of the inflammatory process. This approach is not well individualized to the patient as we do not account for the degree of inflammation that may or may not be present in the disease. Improved markers to stratify the extent of inflammation can help to tailor a more personalized approach to treatment.

On Monday November 18, 2024, David Yang, a medical student working with Penn Vasculitis Center reported his research at ACR Convergence on quantifying vessel wall inflammation on MRI, which may help guide further treatment (abstract 2650). He tested the hypothesis  that patients with higher extent of vascular inflammation would be at higher risk of ocular manifestations of GCA. They sought to determine a continuous score to assess cranial vessel wall MRI enhancement. Their study assessed bilateral temporalis muscle, occipital, middle meningeal, and maxillary arteries, along with bilateral segments of the temporal artery including frontal branch, parietal branch, common trunk for a total of 14 evaluated structures. They conducted generalized linear mixed effects model with sum-to-zero contrasts to score the MRI structures and produce the Cranial Artery MRI Score for GCA (CAMRIS-GCA). This score is a continuous scale which grades the degree of inflammation form 0 (no inflammation) to 10 (highest vascular inflammation).

The study included 75 patients with suspected GCA. In this group, 33 were found to have GCA (17 ocular and 16 non-ocular GCA) and 42 without GCA. The GCA patients had increased abnormal MRI enhancement compared to non-GCA patients. The CAMRIS-GCA score was highest in patients with clinical diagnosis of ocular GCA, and in patients with orbital MRI enhancement (0.61 vs. 0.14, p< 0.01). In the study, there were 15 patients who underwent repeat MRI which showed that the CAMRIS-GCA decreases with treatment of GCA.

This valuable study suggests a possible scoring system to quantify vessel wall inflammation on MRI imaging. This can help providers better understand the degree of inflammation present in a new diagnosis of GCA, as well as help risk stratify for risk of ocular disease. These findings can pave a way for a targeted, individualized approach to therapy. The improvements noted while on therapy also suggest that this may also be a tool to follow disease activity while on treatment. 

Future research is certainly needed to assess correlation of the CAMRIS-GCA with clinical outcomes, but this study advances our understanding by quantifying the degree of inflammation rather than simply noting presence or absence.