Epidemiology and genetics of granulomatosis with polyangiitis

An Ovine Model Yields Histology and Gene Expression Changes Consistent with Laryngotracheal Stenosis

OBJECTIVES

Animal models for laryngotracheal stenosis (LTS) are critical to understand underlying mechanisms and study new therapies. Current animal models for LTS are limited by small airway sizes compared to human. The objective of this study was to develop and validate a novel, large animal ovine model for LTS.

METHODS

Sheep underwent either bleomycin-coated polypropylene brush injury to the subglottis (n = 6) or airway stent placement (n = 2) via suspension microlaryngoscopy. Laryngotracheal complexes were harvested 4 weeks following injury or stent placement. For the airway injury group, biopsies (n = 3 at each site) were collected of tracheal scar and distal normal regions, and analyzed for fibrotic gene expression. Lamina propria (LP) thickness was compared between injured and normal areas of trachea.

RESULTS

No mortality occurred in sheep undergoing airway injury or stent placement. There was no migration of tracheal stents. After protocol optimization, LP thickness was significantly increased in injured trachea (Sheep #3: 529.0 vs. 850.8 um; Sheep #4: 933.0 vs. 1693.2 um; Sheep #5: 743.7 vs. 1378.4 um; Sheep #6: 305.7 vs. 2257.6 um). A significant 62-fold, 20-fold, 16-fold, 16-fold, and 9-fold change of COL1, COL3, COL5, FN1, and TGFB1 was observed in injured scar specimen relative to unaffected airway, respectively.

CONCLUSION

An ovine LTS model produces histologic and transcriptional changes consistent with fibrosis seen in human LTS. Airway stent placement in this model is safe and feasible. This large airway model is a reliable and reproducible method to assess the efficacy of novel LTS therapies prior to clinical translation.

LEVEL OF EVIDENCE

N/A Laryngoscope, 2024.

HLA sequencing identifies novel associations and suggests clinical relevance of DPB1*04:01 in ANCA-associated Granulomatosis with polyangiitis

Granulomatosis with polyangiitis (GPA) is a rare systemic autoimmune disease. Major contributions of HLA genes have been reported; however, HLA typing-based diagnosis or risk prediction in GPA has not been established. We have performed a sequencing-based HLA genotyping in a north Indian GPA cohort and controls to identify clinically relevant novel associations. PR3-ANCA-positive 40 GPA patients and 40 healthy controls from north India were recruited for the study. Targeted sequencing of HLA-A,-B,-C,-DRB1,-DQB1, and -DPB1 was performed. Allelic and haplotypic associations were tested. Molecular docking of susceptibility HLA alleles with reported super-antigen epitopes was performed. The association of substituted amino acids located at the antigen-binding domain of HLA was evaluated. Genetic association of five HLA-alleles was identified in GPA. The novel association was identified for C*15:02 (p = 0.04; OR = 0.27(0.09-0.88)). The strongest association was observed for DPB1*04:01 (p < 0.0001; OR = 6.2(3.08-11.71)), previously reported in European studies. 35 of 40 GPA subjects had at least one DPB1*04:01 allele, and its significant risk was previously not reported from the Indian population. Significantly associated haplotypes DRB1*03:01-DQB1*02:01-DPB1*04:01 (p = 0.02; OR = 3.46(1.11-12.75)) and DRB1*07:01-DQB1*02:02-DPB1*04:01 (p = 0.04; OR = 3.35(0.95-14.84)) were the most frequent in GPA patients. Ranging from 89 % to 100 % of GPA patients with organ involvement can be explained by at least one DPB1*04:01 allele. A strong interaction between the HLA and three epitopes of the reported super antigen TSST-1 of Staphylococcus aureus was confirmed. Our study highlighted the potential applicability of HLA typing for screening and diagnosis of GPA. A large multi-centric study and genotype-phenotype correlation analysis among GPA patients will enable the establishment of HLA-typing based GPA diagnosis.

Subclinical microvascular changes in ANCA-vasculitides: the role of optical coherence tomography angiography and nailfold capillaroscopy in the detection of disease-related damage

BACKGROUND

Both cardiovascular and complement-mediated disorders might lead to microvascular damages in anti-neutrophil cytoplasm autoantibodies (ANCA)-associated vasculitides (AAV). We aimed at investigating, for the first time, subclinical microvascular abnormalities with non-invasive techniques in AAV patients by analyzing both retinal and nailfold capillary changes. Retinal plexi were investigated using optical coherence tomography angiography (OCT-A), while nailfold capillary changes by video-capillaroscopy (NVC). Potential correlations between microvessels' abnormalities and disease damage were also explored.

METHODS

An observational study was conducted on consecutive patients who met the inclusion criteria of defined diagnosis of eosinophilic granulomatosis with polyangiitis (EGPA), granulomatosis with polyangiitis (GPA), and microscopic polyangiitis (MPA), age ≥ 18 ≤ 75 yrs, and no ophthalmological disorders. Disease activity was assessed by Birmingham Vasculitis Activity Score (BVAS), damage by Vasculitis Damage Index (VDI), and poorer prognosis by the Five Factor Score (FFS). Quantitative analysis of vessel density (VD) was performed by OCT-A in both superficial and deep capillary plexi. Figures and detailed analysis from NVC were performed for all subjects in the study.

RESULTS

Included AAV patients (n = 23) were compared with 20 age/sex-matched healthy controls (HC). Retinal VD in superficial whole and parafoveal plexi resulted significantly decreased in AAV compared to HC (P = 0.02 and P = 0.01, respectively). Furthermore, deep whole and parafoveal vessel density was strongly reduced in AAV than HC (P ≤ 0.0001 for both). In AAV patients, significant inverse correlations occurred between VDI and OCTA-VD in both superficial (parafoveal, P = 0.03) and deep plexi (whole, P = 0.003, and parafoveal P = 0.02). Non-specific NVC pattern abnormalities occurred in 82% of AAV patients with a similar prevalence (75%) in HC. In AAV, common abnormalities were edema and tortuosity in a comparable distribution with HC. Correlations between NVC changes and OCT-A abnormalities have not been described.

CONCLUSION

Subclinical microvascular retinal changes occur in patients with AAV and correlate with the disease-related damage. In this context, the OCT-A can represent a useful tool in the early detection of vascular damage. AAV patients present microvascular abnormalities at NVC, whose clinical relevance requires further studies.

The pharmacological treatment of granulomatosis with polyangiitis: a review of clinical trials registered in clinicaltrials.gov and the International Clinical Trials Registry Platform

To date, there is no published overview of the drug pipeline in granulomatosis with polyangiitis (GPA), a rare disease. The aim of this study was to identify clinical trials from two study repositories. A review of clinical trials was conducted using publicly available data. Clinicaltrials.gov and International Clinical Trials Registry Platform were searched from inception until 25 September 2022. Only GPA-specific studies were included; these were described in detail. A total of 137 studies were identified in the trial repositories, of which 108 (79%) studies were found to concern GPA. Of these 108 studies, 67 enrolled GPA patients to investigate pharmacotherapy in this disease (62%). Most studies included all severity types (n = 51; 76%); the scope of almost half of the studies was remission induction (n = 33; 49%). The drug class which was by the most widely investigated in trials was the non-corticosteroid immunosuppressant drug class (46; 68.7%), monoclonal antibodies (32; 47.8%), and corticosteroids (31; 46.3%). There is a need for more GPA trials to generate evidence on effectiveness in terms of severity-specificity and maintenance of remission.

Adult and childhood vasculitis

Vasculitis refers to heterogeneous clinicopathologic disorders that share the histopathology of inflammation of blood vessels. Unrecognized and therefore untreated, vasculitis of the nervous system leads to pervasive injury and disability, making this a disorder of paramount importance to all clinicians. There has been remarkable progress in the pathogenesis, diagnosis, and treatment of primary CNS and PNS vasculitides, predicated on achievement in primary systemic forms. Primary neurological vasculitides can be diagnosed with assurance after intensive evaluation that incudes tissue confirmation whenever possible. Clinicians must choose from among the available immune modulating, suppressive, and targeted immunotherapies to induce and maintain remission status and prevent relapse, unfortunately without the benefit of RCTs, and tempered by the recognition of anticipated medication side effects. It may be said that efforts to define a disease are attempts to understand the very concept of the disease. This has been especially evident in systemic and neurological disorders associated with vasculitis. For the past 100 years, since the first description of granulomatous angiitis of the brain, the CNS vasculitides have captured the attention of generations of clinical investigators around the globe to reach a better understanding of vasculitides involving the central and peripheral nervous system. Since that time it has become increasingly evident that this will necessitate an international collaborative effort.

Granulomatous polyangiitis misdiagnosed as hematogenous lung abscess: A case report

Granuloma polyangiitis (GPA) is a necrotizing granulomatous inflammation, which is a systemic autoimmune disease that mainly affects the upper respiratory tract, lungs, and kidneys. Clinically, the clinical manifestations of GPA vary greatly, and it is extremely easy to be misdiagnosed. We report a 60‐year‐old man with granulomatous polyangiitis with dysuria and parotid gland enlargement as the first symptom. As the condition worsened, he gradually developed symptoms in multiple systems such as persistent high fever, nosebleeds, hemoptysis, skin rash, and multiple cavities in the lungs. Due to high fever, hemoptysis, and the gradual expansion of lung cavities, the suspected hematogenous lung abscess was not well controlled and transferred to the respiratory department. The manifestation of involvement was finally confirmed by skin biopsy. Biopsy was performed on the skin of the lower extremities with a dark red rash with multiple microprojections. Pathology indicated neutrophilic infiltration and necrosis of small vessel walls, and granuloma formation. Blood anti‐protease 3 antibody (PR3) was positive Monotherapy with prednisone. Body temperature gradually returned to normal; hemoptysis and nasal bleeding disappeared; parotid gland enlargement and dysuria relieved, and lung cavities gradually reduced. When anti‐infective treatment is ineffective, we should consider the presence of some non‐infectious diseases, especially when multiple systems are involved; biopsy should be performed as soon as possible. Granulomatous polyangiitis has various manifestations. Parotid glands and prostate may also be the first organs involved, not limited to common targets such as the respiratory tract and kidneys.

Predictors of relapse in granulomatosis with polyangiitis: a multi-center study

Background

Granulomatosis with polyangiitis (GPA) is a rare systemic vasculitis. Its severity ranges from indolent disease to fulminant that may cause death. With treatment, remission is seen in more than 80% of cases, although relapse is still common. There have been studies showing that there may be factors to predict relapse in GPA. Based on relapses, the decision to start treatment and/or to monitor the patients more closely is made. Therefore, predicting the relapse of GPA can be effective in controlling the disease. Our aim was to investigate possible factors for relapse in GPA.

We recruited 254 patients diagnosed with GPA who were under treatment at Alzahra hospital affiliated to Isfahan University of Medical Sciences (from 2013 to 2020) and Amir Alam Hospital affiliated to Tehran University of Medical Sciences (from 2020 to 2022) to plan a retrospective study. Chi-squared or Fisher’s exact tests were performed to compare categorical variables, while the Mann–Whitney U test was used to compare continuous variables.

Results

Analysis of our patients (aged 20–80,122 females) showed that 147 patients (57.9%) experienced relapse. Mean age in relapse group was 43.8 ± 16.6 and in no-relapse group was 45.6 ± 15.1 (P > 0.05). Among many potential predictors, we observed in multivariate analysis that positive PR3-ANCA (proteinase 3-antineutrophilic cytoplasmic antibodies) (P = 0.007, OR:2.62,CI:1.29–5.31),nose manifestations (P = 0.004, OR 3.00, CI 1.43–6.26), mucosal membranes involvement (P = 0.009, OR 4.21, CI 1.43–12.38), and gastrointestinal tract (GI) complications (P = 0.03, OR 5.64, CI 1.14–27.90) were significant predictors of GPA relapse.

Conclusion

Among clinical and laboratory features we studied, positive PR3-ANCA, nose manifestations, mucosal membranes involvement, and GI complications were independent predictors of relapse in patients with GPA.

Pulmonary renal syndrome: a clinical review

The term "pulmonary renal syndrome" describes a clinical syndrome which is characterised by the presence of both diffuse alveolar haemorrhage and glomerulonephritis. It encompasses a group of diseases with distinctive clinical and radiological manifestations, as well as different pathophysiological processes. The most common diseases implicated are anti-neutrophil cytoplasm antibodies (ANCA)-positive small vessel vasculitis and anti-glomerular basement membrane (anti-GBM) disease. Prompt recognition is required as respiratory failure and end-stage renal failure can rapidly occur. Treatment includes a combination of glucocorticoids, immunosuppression, plasmapheresis and supportive measures. The use of targeted treatments has significantly reduced mortality. Thus, an understanding of pulmonary renal syndrome is essential for the respiratory physician.

Old known and possible new biomarkers of ANCA-associated vasculitis

Antineutrophil cytoplasm antibody (ANCA)-associated vasculitis (AAV) comprises a group of multisystem disorders involving severe, systemic, small-vessel vasculitis with short- and long term serious and life-threating complications. Despite the simplification of treatment, fundamental aspects concerning assessment of its efficacy and its adaptation to encountered complications or to the relapsing/remitting/subclinical disease course remain still unknown. The pathogenesis of AAV is complex and unique, and despite the progress achieved in the last years, much has not to be learnt. Foremost, there is still no accurate marker enabling us to monitoring disease and guide therapy. Therefore, the disease management relays often on clinical judgment and follows a" trial and error approach". In the recent years, an increasing number of new molecules s have been explored and used for this purpose including genomics, B- and T-cell subpopulations, complement system factors, cytokines, metabolomics, biospectroscopy and components of our microbiome. The aim of this review is to discuss both the role of known historical and clinically established biomarkers of AAV, as well as to highlight potential new ones, which could be used for timely diagnosis and monitoring of this devastating disease, with the goal to improve the effectiveness and ameliorate the complications of its demanding therapy.

Meta-analysis confirmed genetic susceptibility conferred by multiple risk variants from CTLA4 and SERPINA1 in granulomatosis with polyangiitis

BACKGROUND

Granulomatosis with polyangiitis (GPA) is a rare systemic autoimmune disease. Smaller sample size and complex nature of the disease pathogenesis has made it challenging to perform well-powered genetic investigations. We performed a systematic review based meta-analysis in GPA to investigate the genetic susceptibility conferred by non-human leukocyte antigen (non-HLA) candidate genes.

METHODS

A systematic review was performed using web-based literature search and eligible studies were included following inclusion-exclusion criteria. Studies were evaluated for their quality of evidence and study outcome was assessed using the Newcastle-Ottawa Scale and Grades of Research, Assessment, Development and Evaluation tools. Reviewer's agreement was accessed through Cohen's κ value. Meta-analyses were performed using RevMan 5 tool. Meta-odds ratio (meta-OR) and Z test P value were evaluated to estimate the genetic susceptibility for each of the variants.

RESULTS

Eighteen studies were found eligible and 7 genetic variants from only 4 genes, namely CTLA4, PRTN3, SERPINA1 and PTPN22 could be studied for meta-analysis. rs231775-G (49-G) (Meta-OR = 1.42 [1.14-1.76]; P = .001) of CTLA4 and rs7151526-A (Meta-OR = 2.70 [1.51-4.85]; P = .0008) of SERPINA1 were confirmed to be predisposing alleles, and rs5742909-C (318-C) (Meta-OR = 0.65 [0.44-0.97]; P =.03) of CTLA4 was found to be protective for GPA. In concordance with the genetic association of rs7151526-A, serological marker for the same variant "Z" allele of SERPINA1 was found to be predisposing (Meta-OR = 12.60 [5.01-31.68]; P < .00001) for GPA.

CONCLUSION

Genetic variants confirmed in this study play critical roles in T-cell mediated immune function and could be significantly implicated in GPA. Molecular pathology studies are warranted to confirm their role. These markers could be used for efficient patient classification and disease management.

Infections or Vaccines Associated with Finkelstein-Seidlmayer Vasculitis: Systematic Review

Finkelstein-Seidlmayer vasculitis, also referred to as acute hemorrhagic edema of young children, is a rare small-vessel leukocytoclastic vasculitis. This condition is skin-limited, mainly affects infants up to 2 years of age and spontaneously remits. It has been suggested that an infection or a vaccine precede (by ≤ 14 days) this vasculitis. To better understand the interplay between infections or vaccines and Finkelstein-Seidlmayer vasculitis, we utilized the data contained in the Acute Hemorrhagic Edema BIbliographic Database AHEBID. The database, initiated in 2019, is being regularly updated, encompasses the entire original literature on Finkelstein-Seidlmayer vasculitis published after the original description and is attainable on request. The possible existence of an infectious or a vaccine precursor was addressed in 447 cases. Most cases were preceded by an infection (N = 384; 86%), by a vaccination (N = 20; 4.4%), or both an infection and a vaccination (N = 17; 3.8%). No precursor was reported in the remaining cases (N = 26; 5.8%). Two distinct infections preceded the onset of the vasculitis in 11 of the 381 cases with infection-associated Finkelstein-Seidlmayer vasculitis. The following infectious precursors were reported: upper respiratory tract infection (N = 292); acute gastroenteritis (N = 40); a benign febrile infection (N = 36); lower respiratory tract infection (N = 22); further infections (N = 8). The temporal relationship between the infectious precursor and the onset of the skin eruption was detailed in 336 cases: 54 cases developed before resolution and 282 after resolution of the infection. In conclusion, most cases of Finkelstein-Seidlmayer vasculitis are preceded by an infection. In a minority of cases, this skin vasculitis develops before resolution of the infection. In most cases, however, this vasculitis develops after resolution of the infection. More rarely, this vasculitis is preceded by a vaccination.