Unmet Needs in the Pathogenesis and Treatment of Vasculitides

A Successful Infliximab Treatment of a Pediatric Case of Severe Polyarteritis Nodosa With a Cerebral Infarction and a Decreased Adenosine Deaminase 2 Activity

Polyarteritis nodosa (PAN) is a systemic necrotizing vasculitis common in males over 50 years of age that causes various organ symptoms. In recent years, it has become important to distinguish deficiency of adenosine deaminase 2 (DADA2) from childhood-onset PAN. A 13-year-old girl was urgently transferred to our hospital with sudden weakness in her right upper and lower limbs. The National Institutes of Health Stroke Scale (NIHSS) was 8. Plain MRI of the brain indicated high-signal areas in the right caudate nucleus, internal capsule, and left basal ganglia when applying T2-weighted, fluid-attenuated inversion recovery (FLAIR), and diffusion-weighted imaging (DWI); and low signals in the same regions in an apparent diffusion coefficient (ADC) map. It demonstrated inflammatory demyelinating disease of the central nervous system or multiple cerebral infarctions attributable to vasculitis, and it is difficult to differentiate between them based on image findings alone, and cannot be determined without following the clinical course. Hence, we treated with steroid therapy, which is effective for both conditions. Although the paralysis was alleviated, an MRI of the brain reperformed on day 7 revealed expansion of the lesion with contrast enhancement in the feeding area of the left lateral striatal artery, a high signal in DWI, and a low signal in an ADC map. Based on the clinical and radiological findings, we diagnosed a cerebral infarction attributable to vasculitis. Contrast computed tomography (CT) of her chest and abdominal CT angiography revealed that she met the diagnostic criteria for PAN, and adenosine deaminase 2 (AD2) activity level was low. The patient was treated with steroids combined with azathioprine and cyclophosphamide but three weeks after discharge developed a new cerebral infarction in the right basal ganglia. We commenced infliximab; no recurrence of cerebral infarction has been noted. The low AD2 activity may explain the intractable atypical course of this case. Further studies are needed to reveal the role of AD2 in patients with residual enzyme activity and reevaluation of the PAN diagnostic criteria is essential.

Biologic therapy in large and small vessels vasculitis, and Behçet's disease: Evidence- and practice-based guidance

OBJECTIVE

Vasculitis are a very heterogenous group of systemic autoimmune diseases, affecting large vessels (LVV), small vessels or presenting as a multisystemic variable vessel vasculitis. We aimed to define evidence and practice-based recommendations for the use of biologics in large and small vessels vasculitis, and Behçet's disease (BD).

METHODS

Recommendations were made by an independent expert panel, following a comprehensive literature review and two consensus rounds. The panel included 17 internal medicine experts with recognized practice on autoimmune diseases management. The literature review was systematic from 2014 until 2019 and later updated by cross-reference checking and experts' input until 2022. Preliminary recommendations were drafted by working groups for each disease and voted in two rounds, in June and September 2021. Recommendations with at least 75% agreement were approved.

RESULTS

A total of 32 final recommendations (10 for LVV treatment, 7 for small vessels vasculitis and 15 for BD) were approved by the experts and several biologic drugs were considered with different supporting evidence. Among LVV treatment options, tocilizumab presents the higher level of supporting evidence. Rituximab is recommended for treatment of severe/refractory cryoglobulinemic vasculitis. Infliximab and adalimumab are most recommended in treatment of severe/refractory BD manifestations. Other biologic drugs can be considered is specific presentations.

CONCLUSION

These evidence and practice-based recommendations are a contribute to treatment decision and may, ultimately, improve the outcome of patients living with these conditions.

Chemokines and chemokine receptors in Behçet's disease

Behçet's disease (BD), a chronic vascular inflammatory disease, is characterized by the symptoms of ocular lesions, recurrent genital and oral ulcers, skin symptoms and arthritis in addition to neurological, intestinal and vascular involvement. The pathogenesis of BD is poorly understood, and there are no effective laboratory markers for the diagnosis of BD. In addition, BD is presently incurable. Chemokines, a family of small secreted chemotactic cytokines, interact with chemokine receptors and mediate the migration, localization and cellular interactions of inflammatory cells. Several studies have suggested that chemokines and their receptors play an important role in the occurrence and development of BD and that these chemokines along with their receptors can be utilized as biomarkers and therapeutic targets. In the present review, chemokines and chemokine receptors involved in BD and their potential application in diagnosis and therapy have been discussed.

Unmet needs in ANCA-associated vasculitis: Physicians' and patients' perspectives

In recent years, clinical research has increased significantly and therapies for antineutrophil cytoplasmic antibody (ANCA)-associated vasculitis have improved. However, there are still unanswered questions and unmet needs about AAV patients. The purpose of this review is to examine the frontiers of research related to emerging biomarkers eventually predicting relapse, and new therapeutic approaches, not to mention new quality of life assessment tools. Identifying predictors of relapse may help optimize therapeutic strategies, minimize disease recurrence, and reduce treatment-related side effects. In addition, it is important to recognize that patients may suffer long-term consequences of the disease and its treatment, which, although life-saving, is often associated with significant side effects. Our goal, therefore, is to highlight what has been achieved, the pitfalls, and what still needs to be done, comparing the views of physicians and patients.

Selected plasma oxysterols as a potential multi-marker biosignature panel for Behçet's Disease

Clinical, genetic, and medical evidence has shown the inflammatory vasculitis aspect of Behçet's Disease (BD). Whereas oxysterols are vital factors in inflammation and oxidative stress, it is still unknown whether they are involved in the pathophysiology of BD. The current study aims to explore the profile of oxysterols in plasma of BD patients. Thirty patients diagnosed with BD and forty healthy controls matched for age and gender were included. Results showed that the cholestane-3β,5α,6β-triol, 27-hydroxycholesterol (27-OHC) and cholestanol levels were higher in BD than controls. In addition, plasma levels of 7-ketocholesterol (7-KC) and 25-hydroxycholesterol (25-OHC) were lower in BD patient. However, levels of 24S-hydroxycholesterol (24-OHC) did not significantly differ. For BD patients, the plasma 7-KC level was negatively correlated with the BD activity index (BDAI) while 27-OHC was positively correlated with high-sensitivity C-reactive protein (hs-CRP) in patients with active course of the disease. According to ROC analysis, a remarkable increase in the area under the curve (AUC) with a higher sensitivity (Se) and specificity (Sp) for 7-KC, 25-OHC and 27-OHC combined markers was observed. The present study indicated that the identification of the predictive value of these three-selected biomarkers related to oxidative stress and inflammation in patients should lead to a better identification of the etiological mechanism of BD.

The role of PET/CT in disease activity assessment in patients with large vessel vasculitis

OBJECTIVES

To evaluate the accuracy of PET/CT and of PET vascular activity score (PETVAS) in assessing disease activity and the ability of PETVAS in predicting relapses in a large single-centre cohort of patients with large vessel vasculitis (LVV).

METHODS

We conducted a retrospective cohort study of prospectively collected data of consecutive patients diagnosed with LVV who underwent at least one PET/CT scan between 2007 and 2020. The nuclear medicine physician's interpretation of each PET/CT scan (active/inactive vasculitis) was compared with disease activity clinical judgement (active disease/remission). For each PET/CT scan, the PETVAS score was calculated and its accuracy in assessing disease activity was evaluated. The ability of PETVAS in predicting subsequent relapses was evaluated.

RESULTS

A total of 100 consecutive LVV patients (51 large vessel GCA, 49 Takayasu arteritis) underwent a total of 476 PET/CT scans over a mean follow-up period of 97.5 months. Physician-determined PET/CT grading was able to distinguish between clinically active and inactive LVV with a sensitivity of 60% (95% CI 50.9, 68.7) and specificity of 80.1% (95% CI 75.5, 84.1); the area under the curve (AUC )was 0.70 (95% CI 0.65, 0.75). PETVAS was associated with disease activity, with an age and sex-adjusted odds ratio for active disease of 1.15 (95% CI 1.11, 1.19). A PETVAS ≥10 provided 60.8% sensitivity and 80.6% specificity in differentiating between clinically active and inactive LVV; the AUC was 0.73 (95% CI 0.68, 0.79). PETVAS was not associated with subsequent relapses, with an age and sex-adjusted hazard ratio of 1.04 (95% CI 0.97, 1.11).

CONCLUSIONS

The visual PET/CT grading scale and PETVAS had moderate accuracy to distinguish active LVV from remission. PETVAS did not predict disease relapses.

[Update on etiopathogenesis of small vessel vasculitis]

Small vessel vasculitis is characterized by a necrotizing inflammation of the vessel wall predominantly with involvement of small intraparenchymal arteries, arterioles, capillaries and venules. Medium-sized and occasionally large vessels can also be involved. Antineutrophil cytoplasmic autoantibody (ANCA)-associated vasculitis (granulomatosis with polyangiitis, microscopic polyangiitis, eosinophilic granulomatosis with polyangiitis) are differentiated from immune complex vasculitides based on immunopathological and serological aspects. Immune complex vasculitides include IgA vasculitis, cryoglobulinemic vasculitis, hypocomplementemic urticarial vasculitis (anti-C1q vasculitis) and anti-glomerular basement membrane disease. Epidemiological and next-generation sequencing-based studies have significantly contributed to the identification of predisposing environmental factors and genetic risk factors in recent years. Under specific conditions ANCA and immune complexes can induce premature intravascular activation of neutrophilic granulocytes with degranulation and release of enzymes and reactive oxygen species, which leads to vascular damage. In granulomatosis with polyangiitis and eosinophilic granulomatosis with polyangiitis various factors, such as barrier dysfunction and dysbiosis of the microbiome contribute to extravascular granuloma formation predominantly affecting the respiratory tract.

Management of primary vasculitides with biologic and novel small molecule medications

PURPOSE OF REVIEW

Vasculitides can affect small, medium and/or large vessels, leading to end-organ damage, decreased quality of life and death. Glucocorticoids remain the backbone of treatment for systemic vasculitis but are associated with numerous toxicities. In recent years, the efficacy of glucocorticoid-sparing biologic and novel small molecule therapies has been demonstrated.

RECENT FINDINGS

In giant cell arteritis, tocilizumab was superior to glucocorticoid monotherapy in maintenance remission and cumulative glucocorticoid exposure and is now approved for the treatment of giant cell arteritis. In addition to the previously demonstrated efficacy of rituximab for remission induction in antineutrophil cytoplasmic antibody (ANCA)-associated vasculitis, recent trials have also demonstrated its superiority for remission maintenance compared to alternative approaches. Mepolizumab is superior to standard of care alone with regard to remission rates and glucocorticoid-sparing effect in refractory eosinophilic granulomatosis with polyangiitis. Avacopan has shown significant promise in ANCA-associated vasculitis as part of a glucocorticoid-free induction regimen in a recently completed phase 3 trial. Use of biologics in rarer vasculitides remains guided by reports from small case series.

SUMMARY

Biologics and other novel therapies have an increasingly important role in the management of systemic vasculitis. Additional studies are needed to define their optimal use and to guide their use in more rare forms of vasculitis.

Clinical Approach to Diagnosis and Therapy of Polyarteritis Nodosa

PURPOSE OF THE REVIEW

Polyarteritis nodosa is a rare disease characterized by the necrotizing inflammation of medium-sized arteries. Different etiopathogenetic and clinical variants of the disease have been recognized over the past decades. In the present paper, we review the clinical features, diagnosis, and treatment of the different subtypes of the disease.

RECENT FINDINGS

The diagnosis of polyarteritis nodosa is primarily based on clinical findings, imaging, and histopathological investigations. Microbiological and genetic investigations complement the diagnostic work-up. Idiopathic and hereditary variants of polyarteritis nodosa are treated with immunomodulatory medications such as glucocorticoids, conventional immunomodulatory drugs (e.g., cyclophosphamide) and biologic agents (e.g., tumor necrosis factor inhibitors, interleukin 6 inhibitor), while hepatitis B virus-associated polyarteritis nodosa primarily requires antiviral therapy combined with plasma exchange. PAN is a disease with heterogeneous presentations, severity, and therapeutic approaches. The overall prognosis of this disease is improving, mainly due to early diagnosis and more effective treatments. Treatment choices are guided mainly by the disease subtype and severity. In this review, we have presented the current knowledge on PAN clinical variants, their classification, diagnosis, and treatment approaches.

Heritable and non-heritable uncommon causes of stroke

Despite intensive investigations, about 30% of stroke cases remains of undetermined origin. After exclusion of common causes of stroke, there is a number of rare heritable and non-heritable conditions, which often remain misdiagnosed, that should be additionally considered in the diagnosis of cryptogenic stroke. The identification of these diseases requires a complex work up including detailed clinical evaluation for the detection of systemic symptoms and signs, an adequate neuroimaging assessment and a careful family history collection. The task becomes more complicated by phenotype heterogeneity since stroke could be the primary or unique manifestation of a syndrome or represent just a manifestation (sometimes minor) of a multisystem disorder. The aim of this review paper is to provide clinicians with an update on clinical and neuroradiological features and a set of practical suggestions for the diagnostic work up and management of these uncommon causes of stroke. The identification of these stroke causes is important to avoid inappropriate and expensive diagnostic tests, to establish appropriate management measures, including presymptomatic testing, genetic counseling, and, if available, therapy. Therefore, physicians should become familiar with these diseases to provide future risk assessment and family counseling.

[Update: polyarteritis nodosa]

Polyarteritis nodosa (PAN) is a necrotizing arteritis of medium-sized vessels, which is often fatal if untreated. It frequently affects the skin (nodules and ulcers), the peripheral nervous system (mononeuritis multiplex) and the visceral vessels (stenoses and microaneurysms). The complex diagnostic work-up requires discriminating PAN from infectious, malignant, drug-induced and other inflammatory conditions. It can be subclassified into further variants (idiopathic, associated with hepatitis B, associated with hereditary inflammatory diseases or isolated cutaneous disease). While idiopathic and hereditary inflammatory variants require immunosuppressive treatment, the hepatitis B-associated variant is treated with virustatic agents and plasmapheresis. The isolated cutaneous variant has a good prognosis and rarely requires highly potent immunosuppressives.

The Clinical Impact of Using 18F-FDG-PET/CT in the Diagnosis of Suspected Vasculitis: The Effect of Dose and Timing of Glucocorticoid Treatment

¹⁸F-Fluorodeoxyglucose positron-emission tomography (¹⁸F-FDG-PET) with computed tomography (CT) is effective for diagnosing large vessel vasculitis, but its usefulness in accurately diagnosing suspected, unselected vasculitis remains unknown. We evaluated the feasibility of ¹⁸F-FDG-PET/CT in real-life cohort of patients with suspicion of vasculitis. The effect of the dose and the timing of glucocorticoid (GC) medication on imaging findings were in special interest. 82 patients with suspected vasculitis were evaluated by whole-body ¹⁸F-FDG-PET/CT. GC treatment as prednisolone equivalent doses at the scanning moment and before imaging was evaluated. 38/82 patients were diagnosed with vasculitis. Twenty-one out of 38 patients had increased ¹⁸F-FDG accumulation in blood vessel walls indicating vasculitis in various sized vessels. Vasculitis patients with a positive vasculitis finding in ¹⁸F-FDG-PET/CT had a significantly shorter duration of GC use (median = 4.0 vs 7.0 days, P=0.034), and they used lower GC dose during the PET scan (median dose = 15.0 mg/day vs 40.0 mg/day, p=0.004) compared to ¹⁸F-FDG-PET/CT-negative patients. Vasculitis patients with a positive ¹⁸F-FDG-PET/CT result had significantly higher C-reactive protein (CRP) than patients with a negative ¹⁸F-FDG-PET/CT finding (mean value = 154.5 vs 90.4 mg/L, p=0.018). We found that ¹⁸F-FDG-PET/CT positivity was significantly associated with a lower dose and shorter duration of GC medication and higher CRP level in vasculitis patients. ¹⁸F-FDG-PET/CT revealed clinically significant information in over half of the patients and was effective in confirming the final diagnosis.

Rituximab therapy for primary central nervous system vasculitis: A 6 patient experience and review of the literature

OBJECTIVES

To assess the efficacy and safety of Rituximab (RTX) in adult primary central nervous system vasculitis (PCNSV).

METHODS

We retrospectively assessed the effect of RTX in 6 patients with PCNSV. Five of the 6 were refractory to high dose glucocorticoids (GCs) and/or conventional immunosuppressants (IS). The sixth was newly diagnosed and received RTX in combination with GCs. Clinical evaluation, laboratory tests, and imaging modalities were performed at initial RTX administration and during the follow-up. Treatment response was assessed using the treating physician's global opinion regarding response and the degree of disability using the modified Rankin scale (mRS). We also performed a literature review for previous use of RTX in PCNSV using PubMed, Ovid Medline, and the Cochrane library.

RESULTS

The six patients (3 females) had a median age at diagnosis of 50.5 years (range 17-68 years). All had active disease when RTX was started. In 4 patients, RTX administration was associated with a marked reduction in the number of flares (from 18 before starting RTX to 3 after). One patient, after an initial improvement, had 2 flares when B cells were depleted and he was not able to reduce prednisone below 20 mg/day. A 6th patient had a flare when B cells recovered and retreatment with RTX re-induced and maintained remission. The median mRS score at last visit (median: 2; range 0-4) was lower than that prior to treatment (median 3; range 1-5). The median prednisone daily dose before RTX administration was significantly higher than that at last follow-up (p = .006). In the literature review, we identified 5 papers describing 7 patients treated with RTX. Six patients responded to RTX with clinical and MRI improvement with no reported flares after RTX treatment.

CONCLUSIONS

Our data support a potential role for RTX treatment in selected patients with PCNSV.

Disease activity assessment of rheumatic diseases during pregnancy: a comprehensive review of indices used in clinical studies

Pregnancy requires a special management in women with inflammatory rheumatic diseases (RDs), with the aim of controlling maternal disease activity and avoiding fetal complications. Despite the heterogeneous course of RDs during pregnancy, their impact on pregnancy largely relates to the extent of active inflammation at the time of conception. Therefore, accurate evaluation of disease activity is crucial for the best management of pregnant patients. Nevertheless, there are limitations in using conventional measures of disease activity in pregnancy, as some items included in these instruments can be biased by symptoms or by physiological changes related to pregnancy and the pregnancy itself may influence laboratory parameters used to assess disease activity. This article aims to summarize the current literature about the available instruments to measure disease activity during pregnancy in RDs. Systemic lupus erythematosus is the only disease with instruments that have been modified to account for several adaptations which might interfere with the attribution of signs or symptoms to disease activity during pregnancy. No modified-pregnancy indices exist for women affected by other RDs, but standard indices have been applied to pregnant patients. The current body of knowledge shows that the physiologic changes that occur during pregnancy need to be either adapted from existing instruments or developed to improve the management of pregnant women with RDs. Standardized instruments to assess disease activity during pregnancy would be helpful not only for clinical practice but also for research purposes.

Tocilizumab treatment in refractory polyarteritis nodosa: a case report and review of the literature

Polyarteritis nodosa (PAN) is a rare systemic vasculitis affecting multiple organs. Current standard treatment includes the use of glucocorticoids and cyclophosphamide. Unfortunately, some patients do not respond to this treatment and other therapeutic options are needed. We present a case of a young male with refractory PAN and ongoing biopsy evidence of active vasculitis despite optimal standard therapies, who was successfully treated with interleukin-6 antagonist, tocilizumab. A 24-year-old male presented with severe immobilizing polyneuropathy and myalgias. Clinical features included fasciitis, tenosynovitis, early signs of polyneuropathy, and panniculitis, which were largely refractory to the standard therapies. The previous unsuccessful treatments included high-dose glucocorticoids, methotrexate, cyclophosphamide, rituximab, anakinra, and intravenous immunoglobulins. Magnetic resonance imaging showed signs of myositis, with muscle biopsy confirming the diagnosis of PAN. Rapid clinical improvement and sustained remission occurred after interleukin-6 inhibition with tocilizumab at increased dose of 800 mg every 4 weeks. The used search strategy identified 20 publications of which four articles were included for the further analysis. In total, we report the clinical outcome of five PAN cases from the literature and the present one. The present case and the systematic review of literature suggest that tocilizumab is a possible treatment option for, otherwise, refractory hepatitis B virus negative PAN. Randomized-controlled trials are required to evaluate the safety and efficacy of tocilizumab in PAN.

Higher Frequencies of Lymphocytes Expressing the Natural Killer Group 2D Receptor in Patients With Behçet Disease

Behçet disease (BD) is an inflammatory systemic disease with a fluctuating course, which can affect the skin, eyes, central nervous system, musculoskeletal, gastrointestinal, and vascular systems. No laboratory tests are currently available for the diagnosis of BD and monitoring disease activity. Moreover there is a lack of knowledge on BD pathogenesis. This study focused on circulating Natural Killer (NK), NKT and T cells evaluated as CD3^neg CD56^pos, CD3^pos CD56^pos, and CD3^pos CD56^neg. Peripheral blood mononuclear cells (PBMCs) were collected from 38 BD patients and 20 healthy controls (HC). The frequencies of NK, NKT, and T cells expressing CD16, CD69, NKG2D, Nkp30, Nkp46, and NKG2A were assessed by flow cytometry. Cytotoxic potential of NK cells was evaluated by flow cytometry as the percentage of cells expressing the degranulation marker CD107a after incubation with K562 cells. The levels of 27 cytokines were determined in plasma with a multiplex bead-based assay. Higher percentages of NK, NKT, and T cells expressing NKG2D were detected in PBMCs of BD patients than HC. ROC curve analysis showed that the evaluation of NKG2D^pos NK, NKT, and T cell percentages discriminated between BD patients and HC. Moreover, there was a positive correlation between the BD Current Activity Form (BDCAF) scores and the frequencies of NKG2D^pos NK and NKT cells. A higher frequency of NK cells expressing CD107a was induced in PBMCs from BD patients than HC after incubation with K562 cells. Concentrations of IL-5, IL-6, IL-10, IL-13, IP-10, and MIP-1β were higher in plasma of BD patients than HC. Monitoring the frequencies of NKG2D^pos lymphocytes could help the clinicians in BD patients management. In addition, the increased expression of NKG2D in BD patients is likely involved in disease pathogenesis.