Can we validate a clinical score to predict the risk of severe infection in patients with systemic lupus erythematosus? A longitudinal retrospective study in a British Cohort

Development and Validation of Nosocomial Bacterial Infection Prediction Models for Patients With Systemic Lupus Erythematosus

BACKGROUND

Hospital-acquired bacterial infections are associated with high morbidity and mortality rates in patients with systemic lupus erythematosus (SLE). This study aimed to develop and validate predictive models for the risk of hospital-acquired bacterial infections in patients with SLE.

METHODS

A historical cohort study was designed for development, and another bidirectional cohort study was used for external validation. The risk of bacterial infection was assessed upon admission and after 5 days of hospitalization. Predictor selection employed the least absolute shrinkage and selection operator (LASSO) techniques. Multiple imputations were used to handle missing data. Logistic regression models were applied, and the properties of discrimination, calibration, and decision curve analysis were evaluated.

RESULTS

The development cohort comprised 1686 patients and 237 events (14.1%) from 3 tertiary hospitals. The external validation cohort included 531 patients and 84 infection outcomes (15.8%) from 10 hospital centers in Colombia (secondary and tertiary level). The models applied at admission and after 120 hours of stay exhibited good discrimination (AUC > 0.74). External validation demonstrated good performance among patients from the same tertiary institutions where the models were developed. However, geographic validation at other institutions has been suboptimal.

CONCLUSIONS

Two predictive models for nosocomial bacterial infections in patients with SLE are presented. All infection prevention recommendations should be maximized in patients at moderate/high risk. Further validation studies in diverse contexts, as well as clinical impact trials, are necessary before potential applications in research and clinical care.

Risk stratification for infection during immunosuppressive therapy in patients with lupus nephritis: A nested case-control study

BACKGROUND

The current prediction models for the risk of infection during immunosuppressive treatment for lupus nephritis (LN) lack a prediction time window and have poor pertinence. This study aimed to develop a risk stratification to predict infection during immunosuppressive therapy in patients with LN.

METHODS

This retrospective nested case-control study collected patients with LN treated with immunosuppressive therapy between 2014 and 2022 in the Nephrology ward in Huashan Hospital affiliated to Fudan University and Huashan Hospital Baoshan Branch. Cases were defined as patients who experienced infection during the follow-up period; patients were eligible as controls if they did not have infection during the follow-up period.

RESULTS

There were 53 patients with infection by CTCAE V5.0 grade ≥2. According to the 1:3 nested matching, the 53 patients with infection were matched with 159 controls. In the multivariable logistic regression model, the change rate of fibrinogen (OR = 0.97, 95% CI: 0.94-0.99, p = 0.008), leukopenia (OR = 8.68, 95% CI: 1.16-301.72, p = 0.039), and reduced albumin (OR = 6.25, 95% CI: 1.38-28.24, p = 0.017) were independently associated with infection. The AUC of the ROC curve in the validation set of the multivariable logistic regression model in the internal random sampling was 0.864. The scores range from -2 to 10. The infection risk stratification ranges from 2.8% at score -2 to 97.5% at score 10.

CONCLUSION

A risk stratification was built to predict the risk of infection in patients with LN undergoing immunosuppressive therapy.

SLESIS-R: an improved score for prediction of serious infection in patients with systemic lupus erythematosus based on the RELESSER prospective cohort

OBJECTIVE

To develop an improved score for prediction of severe infection in patients with systemic lupus erythematosus (SLE), namely, the SLE Severe Infection Score-Revised (SLESIS-R) and to validate it in a large multicentre lupus cohort.

METHODS

We used data from the prospective phase of RELESSER (RELESSER-PROS), the SLE register of the Spanish Society of Rheumatology. A multivariable logistic model was constructed taking into account the variables already forming the SLESIS score, plus all other potential predictors identified in a literature review. Performance was analysed using the C-statistic and the area under the receiver operating characteristic curve (AUROC). Internal validation was carried out using a 100-sample bootstrapping procedure. ORs were transformed into score items, and the AUROC was used to determine performance.

RESULTS

A total of 1459 patients who had completed 1 year of follow-up were included in the development cohort (mean age, 49±13 years; 90% women). Twenty-five (1.7%) had experienced ≥1 severe infection. According to the adjusted multivariate model, severe infection could be predicted from four variables: age (years) ≥60, previous SLE-related hospitalisation, previous serious infection and glucocorticoid dose. A score was built from the best model, taking values from 0 to 17. The AUROC was 0.861 (0.777-0.946). The cut-off chosen was ≥6, which exhibited an accuracy of 85.9% and a positive likelihood ratio of 5.48.

CONCLUSIONS

SLESIS-R is an accurate and feasible instrument for predicting infections in patients with SLE. SLESIS-R could help to make informed decisions on the use of immunosuppressants and the implementation of preventive measures.

Tuberculosis remains a leading contributor to morbidity due to serious infections in Indian patients of SLE

INTRODUCTION

Infections are a major cause of morbidity and mortality in systemic lupus erythematosus (SLE). We assessed the incidence and risk factors for major infections in SLE in India.

METHODS

A retrospective review of a cohort of 1354 patients of adult SLE (ACR 1997 criteria) seen between 2000 and 2021 at a single center was conducted. Serious infections (need for hospitalisation, prolonged intravenous antibiotics, disability, or death) were recorded. Cox regression was used to determine factors associated with serious infection and the effects of serious infection on survival and damage.

RESULTS

Among the 1354 patients (1258 females, mean age of 30.3 years, follow-up of 7127.89 person-years), there were 439 serious infections in 339 patients (61.6 per 1000 person-years follow-up). Bacterial infections (N = 226) were the most common infection followed by mycobacterial infections (n = 81), viral (n = 35), and then invasive fungal infections (N = 13). Mycobacterium tuberculosis was the single most common microbiologically confirmed organism with incidence of 1136.4/100,000 person-years with 72.8% of them being extrapulmonary. Infection free survival at 1 year and 5 years was 82.9% and 73.8%. There were 119 deaths with infection attributable mortality in 65 (54.6%). On multivariable Cox regression analysis, higher baseline activity (HR 1.02, 1.01-1.05), gastrointestinal involvement (HR 2.75, 1.65-4.69), current steroid dose (HR 1.65, 1.55-1.76), and average cumulative steroid dose per year (HR 1.007, 1.005-1.009) were associated with serious infection and higher albumin (HR 0.65, 0.56-0.76) was protective. Serious infections led to greater damage accrual (median SLICC damage index of 1 vs. 0) and mortality (HR was 18.2, 32.7 and 81.6 for the first, second, and third infections).

CONCLUSION

Serious infections remain a major cause of mortality and damage accrual in SLE and higher disease activity, gastrointestinal involvement, hypoalbuminemia, current steroid dose, and cumulative steroid dose are the risk factors for it.

Major infections in newly diagnosed systemic lupus erythematosus: an inception cohort study

Objective

To evaluate the risk of major infections and the relationship between major infections and mortality in patients with newly diagnosed SLE.

Methods

A newly diagnosed (<3 months) hospitalised Systemic Lupus Inception Cohort (hSLIC) in our centre during 1 January 2013 and 1 November 2020 was established. All patients were followed up for at least 1 year or until death. Patient baseline characteristics were collected. Major infection events were recorded during follow-up, which were defined as microbiological/clinical-based diagnosis treated with intravenous antimicrobials. The cohort was further divided into a training set and a testing set. Independent predictors of major infections were identified using multivariable logistic regression analysis. Kaplan-Meier survival analyses were conducted.

Results

Among the 494 patients enrolled in the hSLIC cohort, there were 69 documented episodes of major infections during the first year of follow-up in 67 (14%) patients. The major infection events predominantly occurred within the first 4 months since enrolment (94%, 65/69) and were associated with all-cause mortality. After adjustments for glucocorticoid and immunosuppressant exposure, a prediction model based on SLE Disease Activity Index >10, peripheral lymphocyte count <0.8×10⁹/L and serum creatinine >104 µmol/L was established to identify patients at low risk (3%–5%) or high risk (37%–39%) of major infections within the first 4 months.

Conclusions

Newly onset active SLE is susceptible to major infections, which is probably due to underlying profound immune disturbance. Identifying high-risk patients using an appropriate prediction tool might lead to better tailored management and better outcome.

Antimalarial treatment and minimizing prednisolone are associated with lower risk of infection in SLE: a 24-month prospective cohort study

INTRODUCTION/OBJECTIVES

Infections are a major cause of morbidity and death in systemic lupus erythematosus (SLE). Perfecting the understanding of contributors to infection burden in SLE is pivotal to improve management and outcomes. This study aims to identify clinical predictors of infection in SLE.

METHOD

We conducted a prospective cohort study at a referral SLE clinic. Infections were identified at each visit and categorized as (a) any type, (b) serious, (c) non-serious, and (d) bacterial. Survival analysis followed by multivariate Cox regression with an estimation of hazard ratios (HR) with 95% confidence intervals (95%CI) was performed.

RESULTS

We included 259 patients during a mean follow-up of 23.3 ± 5.7 months. The incidence rate of infection of any type was 59.3 cases per 100 patient-years. Multivariate Cox models showed that (a) prednisolone ≥ 7.5 mg/day (HR = 1.95, 95%CI 1.26-3.03) and female gender (HR = 2.08, 95%CI 1.12-3.86) were associated with higher risk of infection of any type; (b) prednisolone ≥ 10 mg/day was associated with higher (HR = 4.32, 95%CI 1.39-13.40), and antimalarials with lower risk (HR = 0.18, 95%CI 0.06-0.51) of serious infection; (c) female gender (HR = 1.92, 95%CI 1.04-3.57) and prednisolone ≥ 7.5 mg/day (HR = 1.89, 95%CI 1.21-2.96) were associated with higher risk of non-serious infection; (d) antimalarials were associated with lower (HR = 0.49, 95%CI 0.26-0.93) and female gender (HR = 5.12; 95%CI 1.62-16.18) with higher risk of bacterial infection.

CONCLUSIONS

The risk of infection was higher in females in this young, well-controlled, low-comorbidity SLE cohort. Antimalarials were associated with lower and prednisolone ≥ 7.5 mg with higher risk of infection. Key Points • Lupus patients treated with prednisolone ≥ 7.5 mg/day were 89% more likely to present infections. • Lupus patients receiving prednisolone ≥ 10 mg/day were four times more likely to present serious infections. • Lupus patients receiving antimalarials were 82% less likely to present serious infections.

Predictive models of infection in patients with systemic lupus erythematosus: A systematic literature review

INTRODUCTION

Having reliable predictive models of prognosis/the risk of infection in systemic lupus erythematosus (SLE) patients would allow this problem to be addressed on an individual basis to study and implement possible preventive or therapeutic interventions.

OBJECTIVE

To identify and analyze all predictive models of prognosis/the risk of infection in patients with SLE that exist in medical literature.

METHODS

A structured search in PubMed, Embase, and LILACS databases was carried out until May 9, 2020. In addition, a search for abstracts in the American Congress of Rheumatology (ACR) and European League Against Rheumatism (EULAR) annual meetings' archives published over the past eight years was also conducted. Studies on developing, validating or updating predictive prognostic models carried out in patients with SLE, in which the outcome to be predicted is some type of infection, that were generated in any clinical context and with any time horizon were included. There were no restrictions on language, date, or status of the publication. To carry out the systematic review, the CHARMS (Critical Appraisal and Data Extraction for Systematic Reviews of Prediction Modelling Studies) guideline recommendations were followed. The PROBAST tool (A Tool to Assess the Risk of Bias and Applicability of Prediction Model Studies) was used to assess the risk of bias and the applicability of each model.

RESULTS

We identified four models of infection prognosis in patients with SLE. Mostly, there were very few events per candidate predictor. In addition, to construct the models, an initial selection was made based on univariate analyses with no contraction of the estimated coefficients being carried out. This suggests that the proposed models have a high probability of overfitting and being optimistic.

CONCLUSIONS

To date, very few prognostic models have been published on the infection of SLE patients. These models are very heterogeneous and are rated as having a high risk of bias and methodological weaknesses. Despite the widespread recognition of the frequency and severity of infections in SLE patients, there is no reliable predictive prognostic model that facilitates the study and implementation of personalized preventive or therapeutic measures.Protocol registration number: PROSPERO CRD42020171638.

The risk of infections in adult patients with systemic lupus erythematosus: systematic review and meta-analysis

Objectives

We conducted a systematic review and meta-analysis to determine the magnitude of infection risk in patients with SLE and evaluate the effect of general and SLE-related factors on infection risk.

Methods

We searched MEDLINE and Embase from inception to July 2018, screening for observational studies that evaluated infection risk in patients with SLE compared with the general population/healthy controls. Outcomes of interest included overall severe infection, herpes zoster infection/reactivation, opportunistic infections, pneumonia and tuberculosis. Random-effects models were used to calculate pooled risk ratios (RRs) for each type of infection. Sensitivity analysis assessed the impact of removing studies with high risk of bias.

Results

Eleven retrospective or prospective cohort studies were included in the meta-analysis: overall severe infection (n = 4), pneumonia (n = 6), tuberculosis (n = 3) and herpes zoster (n = 2). Pooled RRs for overall severe infection significantly increased for patients with SLE compared with the general population/healthy controls [RR 2.96 (95% CI 1.28, 6.83)]. Pooled RRs for pneumonia, herpes zoster and tuberculosis showed significantly increased risk compared with the general population/healthy controls [RR 2.58 (1.80, 3.70), 2.50 (2.36, 2.65) and 6.11 (3.61, 10.33), respectively]. Heterogeneity and evidence of publication bias were present for all analyses, except herpes zoster. Sensitivity analyses confirmed robustness of the results.

Conclusion

Patients with SLE have significantly higher risk of infection compared with the general population/healthy controls. Efforts to strengthen strategies aimed at preventing infections in SLE are needed.

Protocol registration

PROSPERO number: CRD42018109425.

Long-term outcomes in systemic lupus erythematosus: trends over time and major contributors

SLE is a chronic autoimmune rheumatic disorder of high heterogeneity in clinical presentation, treatment response and prognosis. Long-term outcomes in SLE have been dramatically improved over the past decades, however, increased morbidity and mortality, especially among young individuals, still exists. Unmet needs include residual disease activity and frequent flares, glucocorticoid treatment dependency and toxicity, comorbidity burden, reduced health-related quality of life, health disparities and damage. The main determinants of long-term outcomes in SLE are age, sex, race/ethnicity, genetic profile, environmental factors including smoking, disease activity, major organ involvement such as lupus nephritis and CNS involvement, comorbidities including cardiovascular disease and serious infections, coexistence with APS, treatment adherence, socio-economic factors and access to care. In this review we discuss trends in long-term outcomes in SLE over the years and major contributors such as genetic, disease-related, treatment, comorbidity, socio-economic and other factors.

Immunosuppressive Agents and Infectious Risk in Transplantation: Managing the "Net State of Immunosuppression"

Successful solid organ transplantation reflects meticulous attention to the details of immunosuppression, balancing risks for graft rejection against risks for infection. The 'net state of immune suppression' is a conceptual framework of all factors contributing to infectious risk. Assays which measure immune function in the immunosuppressed transplant recipient relative to infectious risk and allograft function are lacking. The best measures of integrated immune function may be quantitative viral loads to assess the individual's ability to control latent viral infections. Few studies address adjustment of immunosuppression during active infections. Thus, confronted with infection in solid organ recipients, the management of immunosuppression is based largely on clinical experience. This review examines known measures of immune function and the immunologic effects of common immunosuppressive drugs and available studies reporting modification of drug regimens for specific infections. These data provide a conceptual framework for the management of immunosuppression during infection in organ recipients.

Systemic lupus erythematosus and risk of infection

INTRODUCTION

Systemic lupus erythematosus (SLE) is an autoimmune disorder that affects almost every organ system and it is treated with immunomodulation and immunosuppression. SLE patients have an intrinsically dysfunctional immune system which is exacerbated by disease activity and leaves them vulnerable to infection. Treatment with immunosuppression increases susceptibility to infection, while hydroxychloroquine use decreases this risk. Infectious diseases are a leading cause of hospitalization and death.

AREAS COVERED

This narrative review provides an overview of recent epidemiology and predictors of infections in SLE, delineates the risk of infection by therapeutic agent, and provides suggestions for risk mitigation. Articles were selected from Pubmed searches conducted between September 2019 and January 2020.

EXPERT OPINION

Despite the large burden of infection, effective and safe preventative care such as universal hydroxychloroquine use and vaccination are underutilized. Future efforts should be directed to quality improvement, glucocorticoid reduction, and validation of risk indices that identify patients at the highest risk of infection.

Pneumocystis jirovecii in immunocompromised patients with rheumatic diseases

Infections, including opportunistic infections, are a major and frequent cause of morbidity and mortality in patients with systemic autoimmune and rheumatic diseases. Pneumocystis jirovecii pneumonia, classically considered to be typical of HIV patients, transplanted patients or patients treated with oncological chemotherapy, is appearing increasingly frequently in these patients. Therefore, rheumatologists should know its mechanism of production, clinical manifestations, treatment and prophylaxis, all of which are addressed in this review.

Contributions of the lupus register of the Spanish Society of Rheumatology (RELESSER) to the knowledge of systemic lupus erythematosus in Spain

The lupus register of the Spanish Society of Rheumatology (RELESSER) is a multicentre register of patients with systemic lupus erythematosus (SLE) under follow-up by Spanish Rheumatology Services. It contains data on a total of 4024 patients with SLE. So far, 14 studies have been published from the transversal phase of RELESSER. Here we report the more relevant contributions of those studies, according to the authors' perspective, concerning cumulative clinical characteristics, level of activity, treatments, refractory disease, damage and mortality. We also review the main results of the analysis regarding incomplete SLE, lupus nephritis, respiratory manifestations, cardiovascular disease, serious infection, malignancies, fibromyalgia, SLE in males, SLE in Hispanics and juvenile-onset SLE, comparing the main characteristics of each subgroup to the global cohort. RELESSER has become one of the most important clinical SLE registers around the world, with a high yield in terms of knowledge generation about the disease in Spain, also useful for the entire scientific community.