Incidence and predictors of severe infections in ANCA-associated vasculitis: a population-based cohort study

Current perspective on infections and mitigation strategies in primary systemic vasculitis

PURPOSE OF REVIEW

The purpose of this review is to summarize and evaluate most recent evidence on the epidemiology of infections and associated risk factors in patients with primary systemic vasculitides (PSV), as well as discuss mitigation strategies including the risk of antibiotic prophylaxis.

RECENT FINDINGS

Infections remain one of the leading causes of mortality in patients with PSV, with rates of severe infection ranging from 16 to 40% in different cohorts. Older age, frailty, renal and pulmonary involvement, and higher burden of comorbidities have been recognized as important patient-associated risk factors. Treatments including higher cumulative doses of glucocorticoids are associated with an increased risk of infections, and recent studies show the potential benefit of interventions such as reduced-dose glucocorticoid regimens. Existing mitigation strategies include screening, vaccination, and infection prophylaxis. The latter remains particularly important for Pneumocystis jirovecii pneumonia; however, the benefit-risk ratio seems to be less clear outside of induction phase (i.e., high dose of glucocorticoids) and optimal treatment duration remains less clear. Patients with PSV are at increased risk of infections, due to disease itself, comorbidities, and treatment side effects. Awareness of the timing and types of infection, as well as mitigation strategies are imperative to ensure treatment success and survival for patients.

Optimal dose of intravenous cyclophosphamide during remission induction therapy in ANCA-associated vasculitis: A retrospective cohort study of J-CANVAS

OBJECTIVES

To identify the optimal dose of intravenous cyclophosphamide (IVCY) for induction therapy for anti-neutrophil cytoplasmic antibody-associated vasculitis.

METHODS

We retrospectively assessed patients with antibody-associated vasculitis who received IVCY every 2-3 weeks during the remission induction phase. The associations of the IVCY dose with infection-free survival and relapse-free survival were analysed using a Cox regression model. We compared patients in three categories: very low-dose (VLD), low-dose (LD), and conventional dose (CD) (<7.5 mg/kg, 7.5-12.5 mg/kg, and >12.5 mg/kg, respectively). The non-linear association between IVCY dose and the outcomes was also evaluated.

RESULTS

Of the 80 patients (median age 72 years), 12, 42, and 26 underwent the VLD, LD, and CD regimens, respectively, of whom 4, 3, and 7 developed infection or died. The adjusted hazard ratios for infection or death were 4.3 (95% confidence interval (CI) 0.94-19.8) for VLD and 5.1 (95% CI 1.21-21.3) for CD, compared with LD. We found the hazard ratio for infection or death increased when the initial IVCY dose exceeded 9 mg/kg. Relapse-free survival did not differ clearly.

CONCLUSION

Low-dose IVCY (7.5-12.5 mg/kg) may result in fewer infections and similar relapse rates compared with the conventional regimen (>12.5 mg/kg).

Kidney transplantation in patients with ANCA-associated vasculitis is associated with a high incidence of post-transplant cancer

BACKGROUND

Antineutrophil cytoplasmic antibody (ANCA)-associated vasculitis (AAV) is a rare disease with limited data on outcomes after transplantation.

METHODS

In this single-center retrospective cohort study, we describe the outcomes of kidney transplant patients with AAV transplanted at our institute from February 2006 to January 2022.

RESULTS

We identified 9 patients among 1026 with a pre-transplant diagnosis of AAV; all patients had received previous treatment with cyclophosphamide. Maintenance immunosuppression after transplantation was tacrolimus-based in 89% of the patients. At the end of a mean follow-up of 132 ± 61.1 months after transplantation, only one case of extrarenal vasculitis relapse was observed. The relapse rate was 0.01 per patient per year, which is comparable to that reported in the literature. However, seven patients were diagnosed with cancer after a mean follow-up of 81.4 months after transplantation; six had skin cancer and three had renal cell carcinoma (RCC) of the native kidneys (cumulative incidence of 78%). One patient died from metastatic squamous cell carcinoma.

CONCLUSION

In this study, we found a noticeable decrease in disease relapse (1 relapse in the present cohort vs 7 relapses in 19 patients in the previous cohort) in kidney transplant patients with AAV compared with previous data from our group (December 1987-January 2006). Conversely, we found a high incidence of post-transplant cancer. This result could be attributed to reduced immunosurveillance due to immunosuppression therapy before and after transplantation. Therefore, constant cancer early diagnosis and prevention is mandatory during the post-transplant follow-up of AAV patients.

Thyroid disease in ANCA-associated vasculitis: a clinical and epidemiological study

OBJECTIVES

To describe clinical and laboratory characteristics and outcomes in patients with antineutrophil cytoplasmic antibody (ANCA)-associated vasculitis (AAV) and thyroid disease (TD). We also aimed to calculate incidence and identify predictors of TD in two large cohorts of patients with AAV.

METHODS

The study comprised 644 patients with AAV in a population-based cohort from southern Sweden (n=325) and a cohort from a specialised vasculitis centre in Cambridge, UK (n=319). Diagnosis and classification of AAV and TD were confirmed by medical record review. Person-years (PY) of follow-up were calculated from AAV diagnosis to the earliest of TD, death or the end of study. Cox-regression analysis was employed to study predictors of TD.

RESULTS

At AAV diagnosis, 100 individuals (15.5%, 77 females) had TD, 59 had myeloperoxidase (MPO)-ANCA+ and 34 had proteinase-3 (PR3)-ANCA+. Patients with TD tended to have lower C reactive protein, lower haemoglobin and fewer constitutional symptoms. Survival and renal survival was greater in those patients with AAV with pre-existing TD. During 4522 PY of follow-up, a further 29 subjects developed TD, yielding an incidence rate of 641/100 000 PY. No analysed factor predicted de novo TD in AAV. The prevalence of TD among patients with AAV in southern Sweden was 18%.

CONCLUSION

TD is a common comorbidity in AAV, affecting nearly one in five. While TD diagnosis is more common in females and MPO-ANCA+, these factors do not predict de novo TD after initiation of AAV treatment, necessitating monitoring of all patients with AAV with respect to this comorbidity.

[Influence of underlying disease and immunosuppression on the immunocompetence in inflammatory rheumatic diseases]

Patients with inflammatory rheumatic diseases have a higher risk of infections in comparison to the general population. For this patient group, in addition to cardiovascular diseases, infections play an important role with respect to morbidity and mortality. Even if it is difficult to make concrete statements with respect to individual diseases, it can be assumed that there is a lower risk of infections in inflammatory joint diseases in comparison to connective tissue diseases and vasculitides. The increased risk of infections is determined by multiple factors, whereby the underlying factors are classified into three main categories: patient-related factors (age, comorbidities, lifestyle), disease-related factors (immunological dysfunction as part of the disease pathophysiology) and drug-related factors (type and dosage of the immunosuppression and/or immunomodulation). An improved understanding of the complexity of these associations enables the optimization of treatment and disease control taking the individual risk factors into account, with the aim of a significant reduction in the risk of infections.

Invasive fungal infection in ANCA-associated vasculitis: Between the Devil and Deep blue sea. Case series and review of the literature

INTRODUCTION

Patients with antineutrophil cytoplasmic antibody-associated vasculitis (AAV) are susceptible to opportunistic infections, including invasive fungal infections (IFI). This is due to many factors, including prolonged immunosuppressive therapy. The treatment of AAV with such IFIs is challenging.

METHODS

A descriptive analysis of 5 patients with AAV complicated by concomitant invasive fungal infections was performed. We also have done a comprehensive literature review of IFIs in AAV using PubMed and Google Scholar databases.

RESULTS

All 5 patients initially received immunosuppressive medication but subsequently acquired IFI. One patient had sphenoid sinus involvement, and four had lung parenchymal involvement. Aspergillus infection was diagnosed in three patients, Cryptococcus infection in one patient and mixed infection with Aspergillus and Mucor infection in one patient. All our patients were on low doses of corticosteroids for several months to years or had received high-dose pulse steroids with cyclophosphamide in the last few weeks before being diagnosed with IFI. It was difficult to distinguish disease activity from IFI in all the cases. Two of the five patients died despite antifungal therapy. The literature review revealed a prevalence of IFIs ranging from 1 to 9.6% (excluding pneumocystis pneumonia). Aspergillosis was the predominant type of IFI, affecting 46 of 86 patients. Most of these patients (40/46) had pulmonary involvement. The prognosis for patients with IFI was consistently poor, as evidenced by 19 deaths out of 29 reported outcomes.

CONCLUSION

Overall, IFIs have a poor prognosis in patients with AAV. Differentiating disease activity from IFI is difficult because of similar organ distribution, imaging lesions, and histopathological characteristics. A high suspicion index and good-quality microbiology are needed for early treatment and prevention of mortality.

Incidence of Pneumocystis Jiroveci Pneumonia in Patients With ANCA-Associated Vasculitis Initiating Therapy With Rituximab or Cyclophosphamide

OBJECTIVE

This manuscript assesses the incidence of Pneumocystis jiroveci pneumonia (PJP) among patients receiving contemporary treatment regimens for antineutrophil cytoplasmic antibody-associated vasculitis (AAV) and adverse events associated with PJP prophylaxis.

METHODS

Incident users of rituximab or cyclophosphamide for AAV were identified in the TriNetX electronic health records database from 2011 to 2022. The incidence rates (IRs) of PJP in the first 6 months of induction therapy with rituximab and/or cyclophosphamide and during postinduction maintenance therapy with rituximab were calculated. Cox proportional hazard models were used to estimate hazard ratios (HRs) and confidence intervals (CIs) for the risk of adverse events commonly associated with PJP prophylaxis.

RESULTS

We identified 1,461 AAV cases who received induction therapy with rituximab (69.7%), cyclophosphamide (18.9%), or both (11.4%). Prophylaxis prescribed within 30 days of induction included trimethoprim-sulfamethoxazole (30.7%), atovaquone (5.4%), dapsone (3.8%), and pentamidine (0.8%). During induction therapy, 10 cases of PJP were identified (IR 15.0 cases per 1,000 patient-years); no deaths occurred. In adjusted analyses, those who received prophylaxis had a higher risk of leukopenia (HR 3.1; 95% CI 1.1-8.6), rash (HR 1.9; 95% CI 1.0-3.6), and nephropathy (HR 2.6; 95% CI 1.3-5.1) than those who did not. During rituximab maintenance therapy (n = 709), five cases of PJP were identified (IR 2.1 cases per 1,000 person-years), one of whom died during the hospitalization associated with a PJP diagnosis.

CONCLUSION

Rates of PJP in patients with AAV were lower than previously observed, and few cases occurred during rituximab maintenance therapy. PJP prophylaxis was associated with adverse events.

Risk factors for hypogammaglobulinemia and association with relapse and severe infections in ANCA-associated vasculitis: A cohort study

OBJECTIVES

B-cell depletion induced by rituximab (RTX) in ANCA-associated vasculitis (AAV) is a risk factor for hypogammaglobulinemia. Aggregating data on gammaglobulin levels kinetics during RTX and its association with the risk of relapse and severe infection is of interest.

METHODS

Gammaglobulin levels were collected before induction therapy and during RTX maintenance therapy. We used different definitions of gammaglobulin decline: 1/gammaglobulin levels <6 g/L after induction; 2/>25 % decline in gammaglobulin levels between induction and maintenance, and 3/both. Our primary objective was the impact of gammaglobulin decline on the risk of relapse and severe infections.

RESULTS

We included 98 patients. Patients with gammaglobulin level <6 g/L after induction and gammaglobulin decline >25 % were older (OR 3.9; 95%CI 1.1-16.1), had more frequently baseline gammaglobulin levels <10 g/L (OR 6.0; 95%CI 1.7-25.8) and received more frequent pulses of methylprednisolone at induction (OR 4.6; 95%CI 1.3-18.5). Severe infection-free survival was significantly poorer in patients with both gammaglobulin <6 g/L and gammaglobulin decline >25 % (adjusted HR 2.3; 95%CI 1.0-5.1) and in those who received pulses of methylprednisolone (HR 5.6; 95%CI 2.3-13.4). Gammaglobulin decline was in contrast not associated with the risk of relapse.

CONCLUSION

Older age, low gammaglobulin levels and pulses of methylprednisolone at induction increase the likelihood of gammaglobulin decline after induction therapy. Such decline was associated with an increased risk of severe infections but not lower risk of vasculitis relapse. Pulses of methylprednisolone at induction had an independent negative impact on gammaglobulin levels and the risk of severe infections.

Impact of different ANCA serotypes on the long-term outcome of ANCA-associated vasculitis patients

OBJECTIVES

To investigate the clinical features and long-term outcomes of Chinese anti-neutrophil cytoplasmic antibodies (ANCAs)-associated vasculitis (AAV) patients with different ANCA serotypes.

METHODS

Two hundred and twenty-four AAV patients from January 2010 to June 2021 were divided into myeloperoxidase (MPO)-ANCA and proteinase 3 (PR3)-ANCA groups. Clinical and long-term outcomes were compared.

RESULTS

In this study, the average follow-up was 46.4 months (range 0.3-188.4 months). One hundred and seventy-seven (79.0%) patients were MPO-ANCA-positive and 47 were PR3-ANCA-positive; the mean age of MPO-ANCA positive patients at diagnosis was elder than that of PR3-ANCA positive patients (67.0 vs. 60.0 years, p = .004). Among PR3-ANCA-positive patients, ear, nose and throat symptoms were more common (p = .014). Between two ANCA serotypes, there were no differences in complement 3 (C3), Birmingham vasculitis activity score (BVAS), five-factor score (FFS) or other organ involvements. For all AAV patients, the overall survival rates at one, three and five years were 80.0%, 67.0% and 56.4%, respectively. The cumulative relapse-free rates of one, three and five years were 89.5%, 76.4% and 68.4%, respectively. The survival of AAV patients was unaffected by the ANCA serotype (p = .23). The ANCA serotype also had no effect on either disease relapse (p = .20) or remission rates (p = .10). In our study, PR3-ANCA patients showed a better long-term survival, as the 5-year survival rate and the 5-year relapse-free survival rate of PR3-ANCA patients were 60.7% and 76.9%, while that of MPO-ANCA patients were 55.2% and 65.8%, respectively. Rather than ANCA serotype, younger patients with milder kidney involvement and lower disease assessment scores (BVAS and FFS) might be more relevant to better prognosis.

CONCLUSIONS

The likelihood of induced remission, patient survival or disease recurrence is all unaffected by ANCA serotypes. A better prognosis is seen in younger patients with milder kidney involvement and lower BVAS/FFS scores.

Association between hypogammaglobulinaemia and severe infections during induction therapy in ANCA-associated vasculitis: from J-CANVAS study

OBJECTIVES

To investigate the association between decreased serum IgG levels caused by remission-induction immunosuppressive therapy of antineutrophil cytoplasmic antibody-associated vasculitis (AAV) and the development of severe infections.

METHODS

We conducted a retrospective cohort study of patients with new-onset or severe relapsing AAV enrolled in the J-CANVAS registry, which was established at 24 referral sites in Japan. The minimum serum IgG levels up to 24 weeks and the incidence of severe infection up to 48 weeks after treatment initiation were evaluated. After multiple imputations for all explanatory variables, we performed the multivariate analysis using a Fine-Gray model to assess the association between low IgG (the minimum IgG levels <500 mg/dl) and severe infections. In addition, the association was expressed as a restricted cubic spline (RCS) and analysed by treatment subgroups.

RESULTS

Of 657 included patients (microscopic polyangiitis, 392; granulomatosis with polyangiitis, 139; eosinophilic granulomatosis with polyangiitis, 126), 111 (16.9%) developed severe infections. The minimum serum IgG levels were measured in 510 patients, of whom 77 (15.1%) had low IgG. After multiple imputations, the confounder-adjusted hazard ratio of low IgG for the incidence of severe infections was 1.75 (95% confidence interval: 1.03-3.00). The RCS revealed a U-shaped association between serum IgG levels and the incidence of severe infection with serum IgG 946 mg/dl as the lowest point. Subgroup analysis showed no obvious heterogeneity between treatment regimens.

CONCLUSION

Regardless of treatment regimens, low IgG after remission-induction treatment was associated with the development of severe infections up to 48 weeks after treatment initiation.

Nation-wide cohort study of remission induction therapy using rituximab in Japanese patients with antineutrophil cytoplasmic antibody-associated vasculitis: Effectiveness and safety in the first 6 months

OBJECTIVES

The aim of this article is to evaluate the effectiveness and safety of rituximab (RTX) for microscopic polyangiitis and granulomatosis with polyangiitis in Japan.

METHODS

In this prospective observational study, all patients with microscopic polyangiitis and granulomatosis with polyangiitis administered RTX were enrolled at each institution. During the observation period of 2 years, data up to 6 months were analysed. Cox proportional hazards analysis was used to assess the factors associated with an outcome.

RESULTS

Of the 75 patients who received RTX for remission induction therapy, 53 achieved remission by the sixth month and 50 were in remission at the sixth month. During therapy, 38 serious adverse events were observed in 24 patients, 21 serious infections in 16 patients, and 9 patients died. No factors were associated with remission; however, there was a significant difference between patients with and without remission in serious adverse events (22.6% vs. 54.5%), serious infections (11.3% vs. 45.4%), and death (1.9% vs. 36.4%). The hazard ratio (95% confidence interval) for serious infection was 3.49 (1.29-9.74) for patients aged ≥ 75 years and 3.53 (1.31-9.53) for pulmonary complications. Four patients maintained remission for 6 months.

CONCLUSIONS

The effectiveness and safety of RTX for microscopic polyangiitis and granulomatosis with polyangiitis for up to 6 months was demonstrated.

Antineutrophil Cytoplasmic Antibody-Associated Vasculitis and the Risk of Developing Incidental Tuberculosis: A Population-Based Cohort Study

Background and Objectives: Treatment for antineutrophil cytoplasmic antibody-associated vasculitis (AAV) must deal with immunosuppression, as well as infections associated with a compromised immune system, such as tuberculosis (TB). Our aim was to examine the risk of incidental TB after diagnosis of AAV. Materials and Methods: This retrospective population-based cohort study was based on the data from the National Health Insurance Research Database in Taiwan. Patients with newly diagnosed granulomatous polyangiitis or microscopic polyangiitis were identified between 1 January 2000 and 31 December 2012. The primary outcome was risk of incidental TB. Cox proportional hazard models were used to evaluate the association between AAV and incidental TB. Results: A total of 2257 patients with AAV and a propensity-score matched cohort of 9028 patients were studied. Overall, patients with AAV were at a 1.48× higher risk of contracting incidental TB than the patients in the matched cohort (adjusted HR 1.48; 95% confidence interval [CI], 1.02-2.15). Note that the highest risk of contracting incidental TB was in the first two years following a diagnosis of AAV, with a nearly 1-fold increase in risk (adjusted HR, 1.91; 95% CI, 1.01-3.60). Female AAV patients were 3.24× more likely than females without AAV to develop TB (adjusted HR 3.24; 95% CI, 1.85-5.67). Conclusions: Patients with AAV exhibit a 48% elevated TB risk, notably, a 91% increase within the first two years postdiagnosis. Female AAV patients face a 3.24 times higher TB risk compared to females without AAV. This study is limited by potential misclassification and overestimation of AAV cases. Clinicians should closely monitor TB risk in AAV patients, especially in females and the initial two years following diagnosis.

T lymphocyte subsets and immunoglobulin and complement levels are associated with the infection status of patients with antineutrophil cytoplasmic antibody-associated vasculitis

BACKGROUND

Infection is the leading cause of death in patients with antineutrophil cytoplasmic antibody-associated vasculitis (AAV). The aim of this study was to characterize the immunological features of infectious events occurring in patients with newly diagnosed AAV and to identify possible risk factors associated with infection.

METHODS

The T lymphocyte subsets, immunoglobulin, and complement levels of the groups were compared between infected group and the noninfected group. Further, regression analysis was conducted to determine the association of each variable with the risk of infection.

RESULTS

280 patients with newly diagnosed AAV were enrolled. The average levels of CD3+ T cells (720.0 vs. 920.5, P < 0.001), CD3+CD4+ T cells (392.0 vs. 547.0, P < 0.001), and CD3+CD8+ T cells (248.0 vs. 335.0, P = 0.001), serum IgG (11.66 g/L vs. 13.59 g/L, P = 0.002), IgA (1.70 g/L vs. 2.44 g/L, P < 0.001), C3 (1.03 g/L vs. 1.09 g/L, P = 0.015), and C4 (0.24 g/L vs. 0.27 g/L, P < 0.001) were significantly lower in the infected group than in the noninfected group. The levels of CD3+CD4+ T cells (adjusted OR 0.997, P = 0.018), IgG (adjusted OR 0.804, P = 0.004), and C4 (adjusted OR 0.001, P = 0.013) were found independently associated with infection.

CONCLUSIONS

Patients of infected AAV and those without infection differ in T lymphocyte subsets and immunoglobulin and complement levels. Furthermore, CD3+CD4+ T cells counts and serum IgG and C4 levels were independent risk factors with infection in patients with newly diagnosed AAV.

Outcomes in ANCA-associated vasculitis patients with end-stage kidney disease on renal replacement therapy-A meta-analysis

BACKGROUND

End-stage kidney disease (ESKD) is associated with poor prognosis in patients with anti-neutrophilic cytoplasmic antibody (ANCA)-associated vasculitis (AAV). This study summarizes the existing evidence regarding outcomes in AAV patients with ESKD on renal replacement therapy.

METHODS

Searches of the MEDLINE and Embase databases were performed from inception until December 2021. Any study reporting outcomes after ESKD in patients with AAV on haemodialysis or peritoneal dialysis was included. The mortality rate per 100 person-years (100 py) calculated with a random-effects meta-analysis model was the primary outcome. Rates of infections and relapses were secondary outcomes.

RESULTS

2470 citations were found; 22 studies of 952 adult patients with over 3600 person-years of follow-up were included. The pooled mortality rate was 10.90 per 100 py (95% CI: 7.11 - 14.68, I² = 90.8%). The pooled 1-year survival was 80.9% (95% CI: 75.6 - 86.1%, I² = 86.1%) while the pooled 5-year survival was 61.0% (95% CI: 46.0 - 76.0%, I² = 0.0%). The pooled severe infection rate was 66.57 per 100 py (95% CI: 13.64 - 119.50, I² = 99.6%). The pooled relapse rate was 6.22 per 100 py (95% CI: 4.64 - 7.80, I² = 46.6%). Only 1 paediatric study met the inclusion criteria and reported a mortality rate of 11.7 ± 1.9 deaths per 100 py (95% CI: 0.23 - 23.20) amongst 9 patients.

CONCLUSIONS

Patients with AAV and ESKD have a lower risk of relapse, but higher infection and mortality rates. More prospective research exploring the role of immunosuppression after ESKD is needed.

Plasma exchange as an adjunctive therapy in anti-neutrophil cytoplasm antibody-associated vasculitis

INTRODUCTION

We summarize evidence for the role of therapeutic plasma exchange (TPE) in the treatment of anti-neutrophil cytoplasm antibody (ANCA)-associated vasculitis (AAV). TPE rapidly removes ANCA IgG, complement and coagulation factors important in the pathogenesis of AAV. TPE has been used in patients with rapidly deteriorating renal function to achieve early disease control, allowing time for immunosuppressive agents to prevent resynthesis of ANCA. The PEXIVAS trial challenged the utility of TPE in AAV, as it did not show benefit of adjunctive TPE on a combined end point of end stage kidney disease (ESKD) and death.

AREAS COVERED

We analyze data from PEXIVAS and other trials of TPE in AAV, an up-to-date meta-analysis, and recently published large cohort studies.

EXPERT OPINION

There remains a role for the use of TPE in AAV in certain groups of patients, in particular those with severe renal involvement (Cr >500 μmol/L or dialysis-dependent). It should be considered in patients with Cr >300 μmol/L and rapidly deteriorating function, or with life-threatening pulmonary hemorrhage. A separate indication is patients double positive for anti-GBM antibodies and ANCA. TPE may have the greatest benefit as part of steroid-sparing immunosuppressive treatment strategies.

Score to assess the probability of relapse in granulomatosis with polyangiitis and microscopic polyangiitis

OBJECTIVE

To develop a score assessing the probability of relapse in granulomatosis with polyangiitis (GPA) and microscopic polyangiitis (MPA).

METHODS

Long-term follow-up data from GPA and MPA patients included in five consecutive randomised controlled trials were pooled. Patient characteristics at diagnosis were entered into a competing-risks model, with relapse as the event of interest and death the competing event. Univariate and multivariate analyses were computed to identify variables associated with relapse and build a score, which was then validated in an independent cohort of GPA or MPA patients.

RESULTS

Data collected from 427 patients (203 GPA, 224 MPA) at diagnosis were included. Mean±SD follow-up was 80.6±51.3 months; 207 (48.5%) patients experienced ≥1 relapse. Relapse risk was associated with proteinase 3 (PR3) positivity (HR=1.81 (95% CI 1.28 to 2.57); p<0.001), age ≤75 years (HR=1.89 (95% CI 1.15 to 3.13); p=0.012) and estimated glomerular filtration rate (eGFR) ≥30 mL/min/1.73 m² (HR=1.67 (95% CI 1.18 to 2.33); p=0.004) at diagnosis. A score, the French Vasculitis Study Group Relapse Score (FRS), from 0 to 3 points was modelised: 1 point each for PR3-antineutrophil cytoplasmic antibody positivity, eGFR ≥30 mL/min/1.73 m² and age ≤75 years. In the validation cohort of 209 patients, the 5-year relapse risk was 8% for a FRS of 0, 30% for 1, 48% for 2 and 76% for 3.

CONCLUSION

The FRS can be used at diagnosis to assess the relapse risk in patients with GPA or MPA. Its value for tailoring the duration of maintenance therapy should be evaluated in future prospective trials.

Utility of the neutrophil-to-lymphocyte ratio in the prediction of anti-neutrophil cytoplasmic antibody-associated vasculitis with infection

OBJECTIVE

This study aimed to evaluate the predictive value of the neutrophil-to-lymphocyte ratio (NLR) for infection in patients with anti-neutrophil cytoplasmic antibody (ANCA)-associated vasculitis (AAV).

METHODS

Newly onset patients with AAV in China were included, and their laboratory tests and disease activity were analyzed. Based on infection, patients were divided into the infection group (A-I) and the non-infection group (A-NI). Univariable and multivariable logistic regression analyses were used to investigate variables that are independently associated with infection.

RESULTS

In total, 418 patients were enrolled. Significantly higher white blood cell count (WBC, p < 0.001), neutrophils (p < 0.001), NLR (p < 0.001), platelet-to-lymphocyte ratio (p < 0.001), monocyte-to-lymphocyte ratio (MLR, p < 0.001), erythrocyte sedimentation rate (ESR, p = 0.032), C-reactive protein (CRP, p < 0.001), procalcitonin (PCT, p < 0.001), and Birmingham vasculitis activity score (BVAS, p = 0.005) were observed in the A-I group than in the A-NI group. It was detected that NLR (ρ = 0.273, p < 0.001), MLR (ρ = 0.153, p = 0.011), ESR (ρ = 0.143, p = 0.020), and PCT (ρ = 0.391, p < 0.001) were positively correlated with BVAS. Furthermore, NLR was not only an independent predictor of infection (adjusted OR: 1.144, 95% CI: 1.059-1.236, p = 0.001), but with the largest area under ROC curve, of which value was 0.750. Notably, the optimal cut-off value of NLR for infection was 6.01, with sensitivity of 70.07% and specificity of 71.68%.

CONCLUSION

Our study demonstrated that in addition to WBC, CRP, ESR, and PCT, NLR should also be used as a beneficial inflammatory indicator to differentiate infection in newly diagnosed AAV. Key Points • NLR was a helpful inflammatory marker in differentiating infection in newly diagnosed AAV.

Risk factors for serious infections in ANCA-associated vasculitis

OBJECTIVES

Severe infections contribute to morbidity and mortality in antineutrophil cytoplasm antibody-associated vasculitis (AAV). This study aimed to identify risk factors associated with severe infections in participants of the Rituximab versus Cyclophosphamide for ANCA-Associated Vasculitis (RAVE) trial.

METHODS

Data on 197 patients recruited into the RAVE trial were analysed. Participants received either rituximab (RTX) or cyclophosphamide (CYC), followed by azathioprine (AZA). Clinical and laboratory data of patients with and without severe infections (≥grade 3, according to the Common Terminology Criteria for Adverse Events version 3.0) were compared. Risk factors for severe infections were investigated using Cox-regression models.

RESULTS

Eighteen of 22 (82%) severe infections occurred within 6 months after trial entry, most commonly respiratory tract infections (15/22, 68%). At baseline, lower absolute numbers of CD19+ cells were observed in patients with severe infections either receiving RTX or CYC/AZA at baseline, while CD5+B and CD3+T cells did not differ between groups. In Cox-regression analysis, higher baseline serum immunoglobulin M levels were associated with the risk of severe infections, whereby a higher baseline total CD19+B cell number and prophylaxis against Pneumocystis jirovecii with trimethoprim-sulfamethoxazole (TMP/SMX) with decreased risk of severe infections. Use of TMP/SMX was associated with lower risk of severe infections in both groups, receiving either RTX or CYC/AZA.

CONCLUSIONS

The use of low-dose TMP/SMX is associated with reduced risk of severe infections in patients with AAV treated with either RTX or CYC/AZA. Reduced B cell subpopulations at start of treatment might be a useful correlate of reduced immunocompetence.

Diagnosing and treating ANCA-associated vasculitis: an updated review for clinical practice

ANCA-associated vasculitides (AAV) are a group of rare, primary, systemic necrotizing small-vessel vasculitides. Granulomatosis with polyangiitis and microscopic polyangiitis account for ∼80–90% of all AAV. Exposure to silica dust, farming and chronic nasal Staphylococcus aureus carriage are associated with increased risk of developing AAV. When a diagnosis of AAV is suspected, as in patients with multisystem organ dysfunction or those with features such as chronic recurrent rhinosinusitis, cavitated lung nodules, palpable purpura or acute kidney injury, then appropriate further investigations are needed, including ANCA testing. In this scenario, a structured clinical assessment should be conducted, evaluating all the organs possibly involved, and tissue biopsy may be necessary for confirmation of the diagnosis. Therapeutic algorithms vary based on the severity of AAV, the clinical diagnosis/ANCA specificity, and the patient’s age, weight, comorbidities and prognosis. Recent data favour rituximab as a preferable option for both induction and maintenance of remission. In addition, regimens with less glucocorticoids are equally effective and safer in inducing remission compared with conventional regimens, and avacopan is an effective glucocorticoid-sparing option. In contrast, there is not compelling evidence to support the routine use of plasma exchange in addition to standard remission-induction therapy in AAV. ANCA and other biomarkers can be helpful in association with clinical assessment to guide diagnosis and treatment decisions. Patients should be frequently evaluated during follow-up for possible disease relapses or treatment-related morbidity, and for monitoring damage accrual, especially metabolic and cardiovascular damage.

Predicting bacterial infection risk in patients with ANCA-associated vasculitis in southwest China: development of a new nomogram

OBJECTIVES

The aim of this study was to develop and assess a risk nomogram of bacterial infection in patients with ANCA-associated vasculitis (AAV) in southwest China.

METHOD

We established a prediction model based on a training dataset of 249 AAV patients. The least absolute shrinkage and selection operator (Lasso) was used to screen feature variables. Multivariate logistic regression analysis was used to build a prediction model for feature variables. Nomogram was used to predict the risk of bacterial infection in AAV patients. Receiver operating characteristic (ROC) curve was used to evaluate and verify the prediction accuracy of the model. Calibration and clinical useful range was assessed using calibration curve and decision curve analysis, respectively.

RESULTS

Bactericidal permeability enhancement protein of ANCAs (BPI-ANCAs), procalcitonin (PCT), and white blood cell (WBC) were the characteristic variables in this study. Nomogram showed that positive BPI-ANCAs and PCT had higher positive predictive value for bacterial infection in AAV patients. The area under curve (AUC) of the model was 0.703 (95% confidence interval: 0.640-0.766). In the validation model, the AUC was 0.745 (95% confidence interval: 0.617-0.872). Decision curve analysis showed that the nonadherence nomogram was clinically useful within the threshold probability range of 0.31-0.85.

CONCLUSIONS

Nomogram combined with BPI-ANCAs and PCT has the guiding significance for predicting bacterial infection risk in AAV. As an ANCA-specific autoantibody, BPI-ANCAs is helpful for clinicians to understand the role of specific autoantibodies in the pathogenesis of AAV. Key Points • BPI-ANCAs, PCT, and WBC could predict bacterial infection in AAV patients. • Nomogram showed that positive BPI-ANCAs had a high positive predictive value for bacterial infection in AAV patients.

Temporal trends in hospitalisation for opportunistic infections in lupus patients in Western Australia

BACKGROUND

Lupus patients often require aggressive immunosuppressive therapy, which increases the risk for infections. We studied the temporal rates for opportunistic infections (OI) and associated mortality in lupus patients hospitalised in Western Australia.

METHODS

All patients hospitalized in the period 1985-2015 with ≥2 ICD based diagnostic codes for SLE were included. OI was defined as a microbiologically confirmed mycobacterial, fungal, or viral infection. Descriptive data are given as median (IQR) and frequency (%) with incidence rates (IR) calculated per 1000 person years and IR trend rates analysed across 10-year periods by least square regression (R2).

RESULTS

The study cohort (n = 1408) contained 85.3% females with age at entry 35 years (IQR 22-51). During median follow-up of 21.1 years (IQR 17.5-29.6) hospitalisation for OI occurred in 121 (8.6%) patients with recurrent or multiple OI observed in 42 (34.7%) patients. During 29.771 thousand person years, a total of 295 OI were diagnosed for an overall IR rate of 9.91 (CI 8.82-11.09)/1000 person years which did not decrease significantly over time (R² 0.14). Significant decreases were however seen in the IR for tuberculosis (R² 0.88), cryptococcal (R² 0.98) and pneumocystis (R² 0.98) infections, with increasing IR observed for other mycobacteria (R² 0.99) and aspergillosis (R² 0.55) and little change seen for H Zoster (R² 0.18) and Varicella (R² 0.10) infections. In-hospital death during OI admission occurred in 9/121 patients (7.4%). There was no significant gender difference in IR or outcome of OI.

CONCLUSIONS

Hospitalization rates for OI in lupus patients have not changed significantly over time, but there has been a clear shift in the underlying OI. The decrease in mycobacterial and pneumocystis infections suggest successful prophylaxis but the increase in viral and mycotic infections indicate a sustained need to improve prevention of these OI in lupus patients.

Infection is associated with increased risk of MPO- but not PR3-ANCA-associated vasculitis

OBJECTIVES

To determine whether development of ANCA-associated vasculitis (AAV) shows a relationship with a prior infection and if prior infection affects disease characteristics and outcome.

METHODS

All incident cases of AAV diagnosed in a defined region of Sweden from 2000 through 2016 were identified. For each case, 10 individuals from the general population, matched for age, sex and area of residence, were selected. Infections occurring in AAV patients and controls prior to the date of AAV diagnosis (index date for respective controls) were identified using an administrative database. Conditional logistic regression models were used to calculate odds ratios (OR) of developing AAV. Occurrence, clinical characteristics and outcome of AAV were analysed with respect to prior infection.

RESULTS

Two-hundred and seventy patients with AAV (48% female) and 2687 controls were included. Prior to diagnosis/index date, 146 (54%) AAV patients had been diagnosed with infection vs 1282 (48%) controls, with OR for AAV 1.57 (95% CI 1.18, 2.19) in those with infections of the upper respiratory tract and 1.68 (1.02, 2.77) in those with pneumonia. Difference from controls was significant in patients with MPO-ANCA 1.99 (95% CI 1.25, 3.1) but not in those with PR3-ANCA 1.0 (0.61, 1.52). Patients with prior infection showed higher disease activity at AAV diagnosis. No differences in disease characteristics, comorbidities or outcome in those with and without prior infections were observed.

CONCLUSIONS

Respiratory tract infections are positively associated with development of MPO- but not PR3-ANCA vasculitis. Prior infection is associated with higher disease activity at AAV diagnosis.

Reasons for hospitalization and in-hospital mortality for anti-neutrophil cytoplasmic antibody vasculitides: analysis of the National Inpatient Sample

OBJECTIVE

Anti-neutrophil cytoplasmic antibody (ANCA)-associated vasculitis (AAV) is a heterogeneous group of conditions resulting in frequent hospitalizations and high in-hospital mortality (IHM). Our study aimed to use the National Inpatient Sample (NIS) to determine and categorize the main reasons for hospital admission and IHM in patients with AAV.

METHODS

We performed a retrospective study of adult AAV hospitalizations in 2016, 2017, and 2018 in acute care hospitals across the USA conducted using the NIS database. We classified the main reasons for hospital admission and IHM into 19 different categories using the principal International Classification of Diseases, Tenth Revision, Clinical Modification (ICD-10) diagnosis.

RESULTS

A total of 41,155 hospitalizations had either a principal or secondary ICD-10 code for AAV (GPA or MPA). Rheumatologic and respiratory diagnoses were the most common reasons for hospitalization, while infectious and respiratory diagnoses were the most common reasons for IHM. Sepsis, unspecified organism A41.9, was the most common specific principal diagnosis for hospitalized and deceased AAV patients.

CONCLUSIONS

Our results show that the leading reasons for hospitalization and mortality for AAV patients were rheumatologic, respiratory, and infectious diagnoses. This data suggests that careful monitoring and management of infectious and pulmonary complications in AAV may improve hospital outcomes. Key points • AAV is a heterogeneous group of conditions resulting in frequent hospitalizations and high IHM. In our study, AAV hospitalizations ended in IHM 4.5% of the time, substantially greater than non-ANCA patients. • The leading reasons for hospital admission for AAV patients were rheumatologic and respiratory diagnoses, but the main reason for IHM were infectious and respiratory diagnoses. • Sepsis was the most common principal diagnosis for hospitalized and deceased AAV patients. • Our results highlight the importance of close monitoring and timely management of infectious and respiratory complications to improve hospitalization outcomes.

The confused puzzles in antineutrophil cytoplasmic antibody-associated vasculitis activity evaluation: A case report

Antineutrophil cytoplasmic antibody (ANCA)-associated vasculitis (AAV) is a group of chronic multisystem autoimmune diseases with substantial mortality and morbidity and frequent relapses. The complexity of the disease condition and treatment-related adverse reactions as well as infections play important roles in the poor outcomes. Unfortunately, the subjective symptoms and objective indicators are not fully parallel, and manifestations between disease activity and treatment-related adverse reactions are often similar. Here, we describe a case of pulmonary mucormycosis in an old female patient with AAV to highlight these challenges.

Interstitial lung disease with myeloperoxidase-antineutrophil cytoplasmic antibody-associated vasculitis in elderly patients

Anti-neutrophil cytoplasmic antibodies-associated vasculitis (AAV) occurs in elderly people, and patients with anti-myeloperoxidase autoantibodies (MPO-ANCA)-positive AAV are often complicated with interstitial lung disease (ILD). This study aimed to evaluate the age-related clinical features of elderly patients with MPO-ANCA-positive AAV-ILD. This study retrospectively investigated 63 patients with MPO-ANCA-positive AAV-ILD, all of whom were 65 years or older at diagnosis. Clinical characteristics, causes of death and survival rates among three groups stratified by age (65-74 years, n = 29; 75-79 years, n = 18; over 80 years, n = 16) were compared. This study also examined the association with severe infections in these patients. Among the three age groups, there were significant differences in sex (P = 0.032), serum Krebs von den Lungen-6 (P < 0.01), and total ground-glass opacity score (P = 0.011). The causes of death were mainly severe infections and complications of ILD. Kaplan-Meier curve analysis showed a significantly lower 5-year survival rate in the oldest group (P < 0.01). Regarding severe infections in these patients, the 5-year cumulative incidence of severe infections was higher in the patients receiving steroid pulse therapy (P = 0.034). The clinical characteristics of MPO-ANCA-positive AAV-ILD differ with age in elderly patients, with age being an important poor prognostic factor in these patients. The administration of steroid pulse therapy is a significant risk factor of severe infection in MPO-ANCA-positive elderly patients with AAV-ILD.