Follow-up vascular ultrasounds in patients with giant cell arteritis.

OBJECTIVES: Literature describing follow-up vascular ultrasound (VUS) in giant cell arteritis (GCA) is limited. We report our experience with follow-up VUS obtained in clinical care of patients with GCA. METHODS: We retrospectively identified GCA patients with an abnormal initial VUS, defined as circumferential hypoechoic wall thickening ("halo sign"), or circumferential hyperechoic wall thickening without evidence of arteriosclerosis or arteritis, who subsequently underwent follow-up VUS during 2013-2018. Studies were interpreted as active arteritis, hyperechoic wall thickening without active arteritis, or no arteritis. We compared clinical and laboratory characteristics at time of initial VUS among patients with active arteritis vs. hyperechoic wall thickening without active arteritis. We described whether and how VUS interpretation changed from initial to follow-up VUS. Among individual vessels, we tested whether abnormal findings (e.g. halo sign) persisted at follow-up VUS using McNemar's test. RESULTS: 42 patients fulfilled study criteria. Median time between initial and follow-up VUS was 5.1 (IQR 2.6-7.9) months. Characteristics at initial VUS did not differ according to VUS interpretation. Among 36 patients with active arteritis on initial VUS, follow-up VUS showed active arteritis in 25.0%, hyperechoic wall thickening in 33.3% and no arteritis in 41.7%. Among 6 patients with hyperechoic wall thickening on initial VUS, half had no arteritis on follow-up VUS. Sonographic findings tended to persist in axillary arteries and were more likely to change in the superficial temporal arteries. CONCLUSIONS: Among 42 GCA patients, the majority had a change in VUS interpretation between initial and follow-up VUS. Sonographic findings in the temporal circulation more frequently changed than findings in axillary arteries.

Clinical Experience With a Multidisciplinary Model of Vascular Ultrasound for the Evaluation for Giant Cell Arteritis.

OBJECTIVE: Vascular ultrasound (VUS) is a first-line test for giant cell arteritis (GCA) in Europe but has been of limited use in the United States. We report clinical experience with a multidisciplinary model of VUS for the evaluation of GCA at a large US medical center. METHODS: Patients who underwent VUS for evaluation of GCA between 2013 and 2017 were reviewed. Trained vascular technologists followed a standardized protocol to visualize bilateral temporal, carotid, subclavian, and axillary arteries. Vascular medicine physicians interpreted VUS as no arteritis, hyperechoic wall thickening, or acute arteritis. Characteristics of patients with versus without acute arteritis (no arteritis or hyperechoic wall thickening) were compared. Among patients with suspected new-onset GCA, the treating physician's pretest and posttest suspicion for GCA were compared. RESULTS: Of 530 patients, 10.6% had prior-onset GCA, 31.7% had polymyalgia rheumatica, and 57.6% were taking glucocorticoids. Most patients had no arteritis on VUS (84.3%); 10.6% had acute arteritis, and 5.1% had hyperechoic wall thickening. Typical GCA symptoms, such as jaw claudication and scalp tenderness, were significantly more frequent in patients with acute arteritis. For all 42 patients with suspected new-onset GCA and acute arteritis, posttest suspicion was unchanged or increased. Of 415 patients with suspected new-onset GCA and VUS without acute arteritis, suspicion decreased (76.4%) or was unchanged (20.2%). CONCLUSION: We describe a multidisciplinary model for incorporating VUS into GCA care. When pretest suspicion was low and VUS did not reveal acute arteritis, posttest suspicion typically decreased, whereas when pretest suspicion was high and VUS revealed acute arteritis, posttest suspicion was reinforced.

Clinically isolated aortitis: imaging features and clinical outcomes: comparison with giant cell arteritis and giant cell aortitis.

(1) describe imaging features of CIA, (2) compare dilation rate and wall thickening of aortic aneurysms in patients with CIA versus those with giant cell arteritis/aortitis (GCA), (3) present clinical outcomes of CIA patients. Retrospective search of electronic records from 2004 to 2018 yielded 71 patients, 52 of whom were female, with a mean age of 67.5 ± 9.0 years old, with a new clinical diagnosis of cranial or extracranial GCA (GCA group), and giant cell aortitis revealed by the aortic biopsy (CIA group). Comparisons between groups were conducted using the Wilcoxon rank-sum and Fisher's exact tests. Survival from the date of initial diagnosis to the end of data collection was compared between the two groups through a log-rank test. CIA patients (n = 23; 32%) presented with cardiovascular symptoms, and none had systemic inflammatory symptoms. Inflammatory markers were significantly higher among GCA patients than among CIA patients (p < 0.0001). The CIA group demonstrated thoracic aortic aneurysms without wall thickening. None of the GCA patients (n = 48; 68%) had aneurysmal dilation in the aorta at the time of diagnosis. None of the four CIA patients had FDG uptake in the aorta, while nine out of 13 GCA patients had FDG uptake in the vessels. There was no statistically significant difference in the survival between the two groups (p = 0.12). CIA patients presented with cardiovascular symptoms and was characterized by aneurysm of the aorta without the involvement of the infrarenal aortic segment. The role of FDG-PET/CT in CIA is less certain, though none of the patients in this cohort had FDG uptake in the vessels.

Investigating the Association of Giant Cell Arteritis with Varicella Zoster Virus in Temporal Artery Biopsies or Ascending Aortic Resections.

OBJECTIVE: A variety of infectious agents, including varicella zoster virus (VZV), have been hypothesized to play a role in the pathogenesis of giant cell arteritis (GCA). The detectability of the virus in patients with GCA is debatable. To further investigate an association between GCA and VZV infection, 10 years of GCA cases were evaluated for VZV by immunohistochemistry (IHC). METHODS: All temporal artery biopsies and ascending aortic resections positive for GCA from 2007 to 2017 at Brigham and Women's Hospital were immunostained using a VZV antibody cocktail (SG1-1, SG1-SG4, NCP-1, and IE-62). RESULTS: Forty-one temporal artery biopsies and 47 ascending aortic resections positive for GCA were identified, all of which were found to be negative for VZV by IHC. Twelve temporal artery biopsies in this cohort were previously analyzed by unbiased metagenomics sequencing and were negative for VZV DNA. CONCLUSION: These results argue against a clinically relevant association between VZV infection and GCA, and support neither routine testing for VZV nor treatment with antiviral drugs.

Characterization of relapses in adult idiopathic inflammatory myopathies.

The objective of the current report was to determine the relapse rates and characterize the nature of relapses during the disease course of adult patients with idiopathic inflammatory myopathies (IIM). A retrospective cohort study of 53 medical records of patients with polymyositis (PM), dermatomyositis (DM), connective tissue disease (CTD)-associated myositis, and malignancy-associated myositis at an academic rheumatology center was performed. Medical records were reviewed to determine clinical presentation, initial treatment, and clinical follow-up, with an emphasis on relapses. Relapses were defined as a sustained elevation in serum creatine kinase (CK) levels in the absence of an alternative etiology. Patients were followed for an average of 65+/-43 months. All patients received corticosteroids, and 35 patients received additional immunosuppressive medications as part of their initial treatment. Serum CK levels normalized in 51 patients, and muscle strength normalized in 43 patients. Biochemical relapse was observed in 33 patients (65%). Patients with PM and CTD-associated myositis had a higher relapse rate compared to DM and malignancy-associated myositis patients. Multiple relapses were observed in 17 patients. Relapses tended to occur within the first 2 years after treatment initiation and during the tapering phase of treatment. No risk factors were unequivocally identified, although advanced age and increased duration of symptoms prior to treatment initiation had nonsignificant associations with increased risk of relapse. In conclusion, initial treatment of IIM results in a high rate of normalization of serum CK and muscle weakness. However, physicians should be aware of the high rate of relapse in patients with IIM.

In search of a candidate pathogen for giant cell arteritis: sequencing-based characterization of the giant cell arteritis microbiome.

OBJECTIVE: To characterize the microbiome of the temporal artery in patients with giant cell arteritis (GCA), and to apply an unbiased and comprehensive shotgun sequencing-based approach to determine whether there is an enrichment of candidate pathogens in the affected tissue. METHODS: Temporal artery biopsy specimens were collected from patients at a single institution over a period of 4 years, and unbiased DNA sequencing was performed on 17 formalin-fixed, paraffin-embedded specimens. Twelve of the 17 patients fulfilled the clinical and histopathologic criteria for GCA, and the other 5 patients served as controls. Using PathSeq software, human DNA sequences were computationally subtracted, and the remaining non-human DNA sequences were taxonomically classified using a comprehensive microbial sequence database. The relative abundance of microbes was inferred based on read counts assigned to each organism. Comparison of the microbial diversity between GCA cases and controls was carried out using hierarchical clustering and linear discriminant analysis of effect size. RESULTS: Propionibacterium acnes and Escherichia coli were the most abundant microorganisms in 16 of the 17 samples, and Moraxella catarrhalis was the most abundant organism in 1 control sample. Pathogens previously described to be correlated with GCA were not differentially abundant in cases compared to controls. There was not a significant burden of likely pathogenic viruses. CONCLUSION: DNA sequencing of temporal artery biopsy specimens from GCA cases, in comparison with non-GCA controls, showed no evidence of previously identified candidate GCA pathogens. A single pathogen was not clearly and consistently associated with GCA in this case series.

Clinical course and management of a consecutive series of patients with "healed temporal arteritis".

OBJECTIVE: To describe the clinical course and management of patients with a pathologic diagnosis of "healed" giant cell arteritis (GCA), and to determine whether previously published histological descriptions of healed arteritis can identify patients with a greater likelihood of clinically significant arteritis. METHODS: All temporal artery biopsy reports between 1994 and 2003 were examined for a diagnosis of "healed arteritis." Two rheumatologists abstracted the medical record for presenting features, physical findings, comorbid conditions, and data on treatment and outcomes. One pathologist, blinded to the clinical data, reviewed all specimens and reinterpreted the biopsies according to published histological descriptions of healed arteritis. RESULTS: Forty-seven patients with an initial pathologic diagnosis of healed arteritis were identified. In 54% of these patients, corticosteroid therapy did not change after the diagnosis of healed arteritis was documented in the pathology report. Seventy percent were ultimately treated with no corticosteroids or low-moderate corticosteroid regimens. Only 32% of the initial cases were confirmed upon review of the biopsies using standardized histological criteria. Patients with confirmed healed arteritis were more likely to have a documented history of polymyalgia rheumatica/GCA and a longer duration of corticosteroid treatment before biopsy. These patients were not more likely to have adverse outcomes. CONCLUSION: In this case series, the diagnosis of healed arteritis had little effect on treatment decisions. In most cases, the initial pathologic diagnosis of healed arteritis was not confirmed when biopsies were reviewed by a single pathologist using uniform histological criteria.