Systemic vasculitides

Applications of Artificial Intelligence in Vasculitides: A Systematic Review

OBJECTIVE

Vasculitides are rare inflammatory disorders that sometimes can be difficult to diagnose due to their diverse presentations. This review examines the use of artificial intelligence (AI) to improve diagnosis and outcome prediction in vasculitis.

METHODS

A systematic search of PubMed, Embase, Web of Science, Institute of Electrical and Electronics Engineers Xplore, and Scopus identified relevant studies from 2000 to 2024. AI applications were categorized by data type (clinical, imaging, textual) and by task (diagnosis or prediction). Studies were assessed for risk of bias using the Prediction Model Risk of Bias Assessment Tool and Quality Assessment of Diagnostic Accuracy Studies-2.

RESULTS

A total of 46 studies were included. AI models achieved high diagnostic performance in Kawasaki disease, with sensitivities up to 92.5% and specificities up to 97.3%. Predictive models for complications, such as intravenous Ig resistance in Kawasaki disease, showed areas under the curves between 0.716 and 0.834. Other vasculitis types, especially those using imaging data, were less studied and often limited by small datasets.

CONCLUSION

The current literature shows that AI algorithms can enhance vasculitis diagnosis and prediction, with deep- and machine-learning models showing promise in Kawasaki disease. However, broader datasets, more external validation, and the integration of newer models like large language models are needed to advance their clinical applicability across different vasculitis types.

Cutaneous vasculitis associated with molecular tergeted therapies: systematic review of the literature

Cutaneo us vasculitis (CV) has a broad spectrum of etiologies, and drugs are one of the main culprits. With the increasing use of targeted therapies in medicine, especially in rheumatology and oncology, the number of CV cases reported due to these drugs has increased. Therefore, the recognition and treatment of CV associated with targeted agents have become more and more important. In the literature, anti-TNFs (n = 73, 59.5%), secukinumab (n = 7, 6%), rituximab (n = 5, 4%), tocilizumab (n = 1, 0.8%), ustekinumab (n = 8, 6.5%), abatacept (n = 3, 2.4%), Janus kinase inhibitors (n = 3, 2.4%), alemtuzumab (n = 3, 2.4%), and immune checkpoint inhibitors (n = 20, 16%) have been reported as responsible agents. However, our knowledge of the pathogenetic mechanisms is fairly limited, and the standardized management is yet to be established. Furthermore, though it is uncommon, this complication may pose a safety issue. In this manuscript, we reviewed the literature on CV with or without systemic involvement related to targeted agents. We also proposed the pathogenetic mechanisms of these adverse events. Thus, we aimed to make it easier for clinicians to manage similar cases by reviewing the diagnosis and treatment processes.

Anti-cytokine targeted therapies for ANCA-associated vasculitis

BACKGROUND

Anti-neutrophilic cytoplasmic antibodies (ANCA)-associated vasculitis (AAV) are a group of rare auto-inflammatory diseases that affects mainly small vessels. AAV includes: granulomatosis with polyangiitis (GPA), microscopic polyangiitis (MPA) and eosinophilic granulomatosis with polyangiitis (EGPA). Anti-cytokine targeted therapy uses biological agents capable of specifically targeting and neutralising cytokine mediators of the inflammatory response.

OBJECTIVES

To assess the benefits and harms of anti-cytokine targeted therapy for adults with AAV.

SEARCH METHODS

We searched the Cochrane Central Register of Controlled Trials (2019, Issue 7), MEDLINE and Embase up to 16 August 2019. We also examined reference lists of articles, clinical trial registries, websites of regulatory agencies and contacted manufacturers.

SELECTION CRITERIA

Randomised controlled trials (RCTs) or controlled clinical trials of targeted anti-cytokine therapy in adults (18 years or older) with AAV compared with placebo, standard therapy or another modality and anti-cytokine therapy of different type or dose.

DATA COLLECTION AND ANALYSIS

We used standard methodological procedures expected by Cochrane.

MAIN RESULTS

We included four RCTs with a total of 440 participants (mean age 48 to 56 years). We analysed the studies in three groups: 1) mepolizumab (300 mg; three separate injections every four weeks for 52 weeks) versus placebo in participants with relapsing or refractory EGPA; 2) belimumab (10 mg/kg on days 0, 14, 28 and every 28 days thereafter until 12 months after the last participant was randomised) or etanercept (25 mg twice a week) with standard therapy (median 25 months) versus placebo with standard therapy (median 19 months) in participants with GPA/MPA; and 3) infliximab (3 mg/kg on days 1 and 14, before the response assessment on day 42) versus rituximab (0.375g/m2 on days 1, 8, 15 and 22) in participants with refractory GPA for up to 12 months. None of the studies were assessed as low risk of bias in all domains: one study did not report randomisation or blinding methods clearly. Three studies were at high risk and one study was at unclear risk of bias for selective outcome reporting. One trial with 136 participants with relapsing or refractory EGPA compared mepolizumab with placebo during 52 weeks of follow-up and observed one death in the mepolizumab group (1/68, 1.5%) and none in the placebo group (0/68, 0%) (Peto odds ratio (OR) 7.39, 95% confidence interval (CI) 0.15 to 372.38; low-certainty evidence). Low-certainty evidence suggests that more participants in the mepolizumab group had ≥ 24 weeks of accrued remission over 52 weeks compared to placebo (27.9% versus 2.9%; risk ratio (RR) 9.5, 95% CI 2.30 to 39.21), and durable remission within the first 24 weeks sustained until week 52 (19.1% mepolizumab versus 1.5% placebo; RR 13.0, 95% CI 1.75 to 96.63; number needed to treat for an additional beneficial outcome (NNTB) 6, 95% Cl 4 to 13). Mepolizumab probably decreases risk of relapse (55.8% versus 82.4%; RR 0.68, 95% CI 0.53 to 0.86; NNTB 4, 95% CI 3 to 9; moderate-certainty evidence). There was low-certainty evidence regarding similar frequency of adverse events (AEs): total AEs (96.9% versus 94.1%; RR 1.03, 95% CI 0.96 to 1.11), serious AEs (17.7% versus 26.5%; RR 0.67, 95% CI 0.35 to 1.28) and withdrawals due to AEs (2.9% versus 1.5%; RR 2.00, 95% CI 0.19 to 21.54). Disease flares were not measured. Based on two trials with different follow-up periods (mean of 27 months for etanercept study; up to four years for belimumab study) including people with GPA (n = 263) and a small group of participants with MPA (n = 22) analysed together, we found low-certainty evidence suggesting that adding an active drug (etanercept or belimumab) to standard therapy does not increase or reduce mortality (3.4% versus 1.4%; Peto OR 2.45, 95% CI 0.55 to 10.97). Etanercept may have little or no effect on remission (92.3% versus 89.5%; RR 0.97, 95% CI 0.89 to 1.07), durable remission (70% versus 75.3%; RR 0.93, 95% CI 0.77 to 1.11; low-certainty evidence) and disease flares (56% versus 57.1%; RR 0.98, 95% CI 0.76 to 1.27; moderate-certainty evidence). Low-certainty evidence suggests that belimumab does not increase or reduce major relapse (1.9% versus 0%; RR 2.94, 95% CI 0.12 to 70.67) or any AE (92.5% versus 82.7%; RR 1.12, 95% CI 0.97 to 1.29). Low-certainty evidence suggests a similar frequency of serious or severe AEs (47.6% versus 47.6%; RR 1.00, 95% CI 0.80 to 1.27), but more frequent withdrawals due to AEs in the active drug group (11.2%) compared to the placebo group (4.2%), RR 2.66, 95% CI 1.07 to 6.59). One trial involving 17 participants with refractory GPA compared infliximab versus rituximab added to steroids and cytotoxic agents for 12 months. One participant died in each group (Peto OR 0.88, 95% CI, 0.05 to 15.51; 11% versus 12.5%). We have very low-certainty evidence for remission (22% versus 50%, RR 0.44, 95% Cl 0.11 to 1.81) and durable remission (11% versus 50%, RR 0.22, 95% CI 0.03 to 1.60), any severe AE (22.3% versus 12.5%; RR 1.78, 95% CI 0.2 to 16.1) and withdrawals due to AEs (0% versus 0%; RR 2.70, 95% CI 0.13 to 58.24). Disease flare/relapse and the frequency of any AE were not reported.

AUTHORS' CONCLUSIONS

We found four studies but concerns about risk of bias and small sample sizes preclude firm conclusions. We found moderate-certainty evidence that in patients with relapsing or refractory EGPA, mepolizumab compared to placebo probably decreases disease relapse and low-certainty evidence that mepolizumab may increase the probability of accruing at least 24 weeks of disease remission. There were similar frequencies of total and serious AEs in both groups, but the study was too small to reliably assess these outcomes. Mepolizumab may result in little to no difference in mortality. However, there were very few events. In participants with GPA (and a small subgroup of participants with MPA), etanercept or belimumab may increase the probability of withdrawal due to AEs and may have little to no impact on serious AEs. Etanercept may have little or no impact on durable remission and probably does not reduce disease flare.

Polyarteritis nodosa and deficiency of adenosine deaminase 2 - Shared genealogy, generations apart

Polyarteritis nodosa (PAN) is a systemic necrotizing vasculitis that predominantly affects medium-sized arteries. With the establishment and refinement of vasculitis nomenclature and diagnostic criteria, clinical findings of PAN and distinguishing features from other vasculitides are now well characterized. Although PAN typically manifests in adulthood, cohort studies in paediatric patients have shaped our understanding of childhood-onset PAN. The paradigm of childhood-onset PAN changed considerably with the landmark discovery of deficiency of ADA2 (DADA2), a monogenic cause of vasculitis that is often indistinguishable from PAN. Testing for DADA2 has provided an explanation to numerous challenging cases of familial PAN and early-onset PAN around the world. The ability to distinguish DADA2 from classic PAN have important therapeutic implications as tumor necrosis factor inhibitors have demonstrated remarkable efficacy in the treatment of DADA2. In this review, we will discuss our current understanding of PAN and DADA2 and highlight similarities and differences between these vasculitides.

Screening of serum samples from Wegener's granulomatosis patients using antibody microarrays

Wegener's Granulomatosis (WG) is an idiopathic granulomatosis autoimmune vasculitis that primarily affects small vessels and is associated with glomerulonephritis and pulmonary granulomatous vasculitis. Anti-neutrophil cytoplasmic auto-antibodies (cANCA) against proteinase-3 are used to identify WG, but ANCA titers are not present in some patients with the localized disease. The objective of this study was to develop an antibody array to help identify protein expression patterns in serum from patients with WG as compared to normals. The arrays were tested for limits of detection, background, and cross reactivity using standard proteins. The arrays were hybridized with either normal patient serum (n = 30) or with serum samples from a population of WG patients (n = 26) that were age and sex matched. Data analysis and curve fitting of the standard dilution series calculated r(2) values and determined a sensitivity of <50 pg/mL for the majority of proteins. A total of 24 proteins were assessed. Several statistically significant increases (p<0.05) were seen in the expression of: angiotensin converting enzyme-I, IFN-γ, IL-8, s-ICAM-1 and s-VCAM in WG patients as compared to controls. Utilizing the antibody microarray technology has led to the identification of potential biomarkers of vascular injury in the serum of WG patients.

Cancer in biopsy-proven giant cell arteritis. A population-based study

OBJECTIVE

To investigate the potential association between giant cell arteritis (GCA) and cancer in a series of consecutive patients diagnosed with biopsy-proven GCA over a 25-year period at the single reference hospital for a well-defined population.

METHODS

The case records of all patients diagnosed with biopsy-proven GCA at the Department of Medicine of the Hospital Xeral-Calde (Lugo, Northwest Spain) between January 1, 1981 and December 31, 2005 were reviewed. Information on cancer and cause of death over the extended follow-up was assessed. In all cases the presence of cancer was histologically confirmed.

RESULTS

Cancer was found in 39 (15.3%) of the 255 GCA patients. Although 7 (18%) of the 39 patients had cancer either at the time or within the first 12 months after GCA diagnosis, the standardized mortality ratio (SMR) due to cancer in patients with biopsy-proven GCA showed no increase (overall SMR 1.06 [0.65-1.60]; men, 0.81; women, 1.50). The time interval between GCA diagnosis and cancer diagnosis was 5.2+/-3.8 years (median 4.2 years; interquartile range: 3-7 years). When multivariate analysis adjusted by age and sex was performed, only the presence of dysphagia (adjusted hazards ratio (HR)=3.90; P=0.04), abnormal temporal artery on physical examination (adjusted HR=4.61; P=0.04), and anemia at the time of GCA diagnosis (adjusted HR=3.39; P=0.01) were associated with an increased risk of cancer over the extended follow-up.

CONCLUSION

The results from this series do not support an overall increase of mortality due to cancer in GCA.

Giant cell arteritis in northwestern Spain: a 25-year epidemiologic study

To continue our investigation of the epidemiology of giant cell arteritis (GCA) in southern Europe, we assessed the potential presence of trends, peaks, and fluctuations in the incidence of this vasculitis over a 25-year period in the Lugo region of northwestern Spain. We also sought to determine whether changes in the clinical spectrum of the disease existed. From 1981 to 2005, biopsy-proven GCA was diagnosed in 255 Lugo residents. The age- and sex-adjusted annual incidence rate was 10.13 (95% confidence interval [CI], 8.93-11.46) per 100,000 population aged 50 years and older. The mean age +/- SD at the time of diagnosis was 75.0 +/- 6.9 years. The annual incidence rate in women (10.23; 95% CI, 8.60-12.08) was slightly greater than that in men (9.92; 95% CI, 8.19-11.89) (p = 0.15). The annual incidence rate increased with advancing age up to a maximum of 23.16 (95% CI, 19.52-27.28) in the 70-79 year age-group. A progressive increase in the incidence was observed from 1981 through 2000 (p = 0.001). However, the age- and sex-adjusted incidence rate for biopsy-proven GCA in the Lugo region did not show peaks in the annual incidence of GCA. Likewise, we observed no seasonal pattern for the diagnosis of the disease. Visual ischemic manifestations and irreversible visual loss were observed in 57 (22.4%) and 32 (12.5%) of the 255 patients, respectively. A negative trend manifested by a progressive decline in the number of patients with visual ischemic manifestations (p = 0.021) or permanent visual loss (p = 0.018) was found over the 25-year period of study. The decline in the frequency of visual manifestations of GCA could not be attributed to a shorter delay to diagnosis, as no significant differences were observed when the delays to diagnosis in the 5 consecutive 5-year periods were compared. In conclusion, the current study confirms a progressive increase in the incidence of biopsy-proven GCA in northwestern Spain, and suggests that there has been a change in the clinical spectrum of the disease.

Current pathological and clinical aspects of Buerger's disease in Japan

Since Buerger's disease was first described by Leo Buerger in 1908, many authors have discussed whether it indeed exists and, if so, is a definite clinical entity. Today, Buerger's disease is accepted as a definite vascular disease with a typical clinical picture, natural history, and histopathology; however, the diagnosis of Buerger's disease has been controversial, and the etiology of this vascular occlusive disease has remained unknown because many authors in different countries have their own criteria. Besides, patients with this disease have decreased in number even in Japan, while there has been no change in the number of arteriosclerosis obliterans patients. Currently, only one or two new patients per year are encountered at our outpatient clinic. The purpose of this review is to examine the current epidemiological, pathological, and clinical aspects of Buerger's disease in Japan based on the 222 patient files of our department between 1980 and 2000 and to discuss the pathogenesis, clinical presentation, and various treatment modalities.

Henoch-Schönlein purpura in north-eastern Turkey

AIM

To evaluate the epidemiological and clinical findings in children with Henoch-Schönlein purpura (HSP) admitted during a 10-year period, 1995 to 2004, and to compare them with series from other parts of the world.

METHODS

The medical records of all children aged 17 years or less admitted with a diagnosis of HSP to the Department of Pediatrics of Karadeniz Technical University were evaluated retrospectively for epidemiological and clinical features.

RESULTS

Of 116 children, 73 (63%) were boys. The mean (SD) age at presentation was 8.9 (3.7) years and one-third of them were older than 10 years of age. Over half the cases presented between September and January. All patients had the typical skin rash. Gastro-intestinal manifestations were seen in 64 (55.1%) and joint manifestations, common during the early course of the disease, in 73 (62.9%). Two patients required laparatomy, one for acute abdomen and the other for bowel resection owing to intussusception. Renal manifestations were observed in 36 (31%), all within 3 months of initial symptoms, and one patient (0.8%) with nephritic syndrome progressed to end-stage renal disease. Five patients had hypertension without urinary findings. Symptoms recurred in eight patients (6.9%) over a period ranging from 2 to 5 months after complete resolution of symptoms. There was a history of a preceding upper respiratory tract infection in 16 (13.7%) and a streptococcal infection was confirmed by throat culture in 12 of the 42 (28.5%) children at presentation.

CONCLUSION

HSP is generally benign and self-limiting. Hypertension may be seen during the course of the disease without urinary findings. In this area, it seems to affect older children and there is a relatively lower incidence of renal manifestations.

Problems in classifying vasculitis in children

Vasculitis is inflammation of blood vessels, which may also affect the arteries of the kidney. The definition and classification of vasculitides derive from the Chapel Hill nomenclature criteria (CHCC) and American College of Rheumatology (ACR) criteria, respectively. These criteria are not perfect, and adult literature refers to problems with misclassification and a low concordance between the two criteria. The problems associated with defining a child patient according to these criteria are even more apparent, since both sets of criteria have been based on adult data alone and have never been validated in children. When classifying their patients as having polyarteritis, paediatricians do not keep strictly to the CHCC or ACR criteria. A recent series has shown that the microscopic polyarteritis associated with MPO-ANCA and the HBs associated with classic polyarteritis nodosa are rarer in children than in adults. Paediatricians should revise the existing criteria based on registries and international consensus in the field.