Infections in hospitalized lupus nephritis patients: characteristics, risk factors, and outcomes

The influence and therapeutic effect of microbiota in systemic lupus erythematosus

Systemic erythematosus lupus (SLE) is an autoimmune disease involving multiple organs that poses a serious risk to the health and life of patients. A growing number of studies have shown that commensals from different parts of the body and exogenous pathogens are involved in SLE progression, causing barrier disruption and immune dysregulation through multiple mechanisms. However, they sometimes alleviate the symptoms of SLE. Many factors, such as genetic susceptibility, metabolism, impaired barriers, food, and sex hormones, are involved in SLE, and the microbiota drives the development of SLE either by depending on or interacting with these factors. Among these, the crosstalk between genetic susceptibility, metabolism, and microbiota is a hot topic of research and is expected to lay the groundwork for the amelioration of the mechanism, diagnosis, and treatment of SLE. Furthermore, the microbiota has great potential for the treatment of SLE. Ideally, personalised therapeutic approaches should be developed in combination with more specific diagnostic methods. Herein, we provide a comprehensive overview of the role and mechanism of microbiota in lupus of the intestine, oral cavity, skin, and kidney, as well as the therapeutic potential of the microbiota.

The association of serum magnesium with infection in new-onset systemic lupus erythematosus patients

OBJECTIVE

To assess the association of serum magnesium with infection in new-onset systemic lupus erythematosus (SLE) patients.

METHODS

We conducted a single-center retrospective cohort study of new-onset SLE patients from 2012 to 2021. The hospitalized SLE patients were divided into infection and noninfection groups. Logistic regression analysis was conducted to examine the association of hypomagnesemia with infection.

RESULTS

A total of 476 new-onset SLE patients were included, with 299 cases in the infection group and 177 cases in the noninfection group. The patients were mostly females (81.7%). The average age at diagnosis was 43.7 years. The median duration was 1.0 month. The prevalence of hypomagnesemia (<0.70), normomagnesemia (0.70-1.10), and hypermagnesemia (>1.10) in new-onset SLE patients was 14.3%, 83.4%, and 2.3%, respectively. The prevalence of hypomagnesemia was 18.4% in the infection group and 7.3% in the noninfection group (p = .001). The baseline value of serum magnesium was 0.819 mmol/L, with values of 0.799 mmol/L in the infection group and 0.854 mmol/L in the noninfection group (p = .000). The following clinical variables were significantly different between the two groups (p < .05): age, duration, hospitalization stay, fever, serositis, and SLE Disease Activity Index 2000 (SLEDAI 2K). The laboratory parameters, including hemoglobin, white blood cell count, albumin level, erythrocyte sedimentation rate (ESR), C-reactive protein (CRP), procalcitonin, and complement C3 were also significantly different between the two groups (p < .05). The mortality was 4.4% (21/476), with 20 cases occurring in the infection group. Logistic regression analysis showed that hypomagnesemia was associated with an increased risk of infection (p = .001) and poor prognosis (p = .015).

CONCLUSION

Hypermagnesemia was rare in new-onset SLE patients. Hypomagnesemia was common and was associated with an increased risk of infection in new-onset SLE 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.

Predisposing Factors of Tuberculosis Infection in Systemic Lupus Erythematosus Patients: A Single-Center Case-Control Study

Introduction: Indonesia has the second-highest tuberculosis cases in the world, according to the global WHO tuberculosis report, amounting to approximately 10% of the world's tuberculosis cases. Systemic lupus erythematosus (SLE) patients are at an increased risk for tuberculosis infection. This research aims to analyze the association between corticosteroid pulse dose, corticosteroid cumulative dose, SLE disease duration, Systemic Lupus Erythematosus Disease Activity Index (SLEDAI) score, and lupus nephritis status with the development of tuberculosis in SLE patients.

Methods: This research was a matched case-control study to identify risk factors of tuberculosis infection in SLE patients. Data were taken from medical records of Cipto Mangunkusumo National General Hospital, a national tertiary hospital. Inclusion criteria were patients who meet the Systemic Lupus Erythematosus International Collaborating Clinics (SLICC) 2012 criteria of SLE in the period of 2012-2016 or patients who meet the SLICC 2012 SLE criteria and developed tuberculosis between 2012 and 2016. Statistical analyses used were bivariate analysis and correlation analysis. All statistical analyses were conducted using SPSS software (IBM Corp., Armonk, NY). All statistical analyses were defined as statistically significant when the p-value was less than 0.05.

Results: A total of 48 SLE patients were included from medical records consisting of 24 SLE patients with tuberculosis infection and controls of 24 SLE patients without tuberculosis infection. In this study, it was observed that the presence of lupus nephritis (p = 0.001), administration of pulse corticosteroids (p = 0.048), high corticosteroid cumulative dose (p = 0.001), and high SLEDAI score (p = 0.003) were associated with tuberculosis infection. Correlation analysis showed that all of these variables had a weak positive correlation with tuberculosis infection in SLE patients.

Conclusion: SLE patients with lupus nephritis, administration of pulse corticosteroids, high cumulative corticosteroid dose, and high SLEDAI score have a higher risk of tuberculosis infection. Clinicians and patients should be aware of these risk factors in SLE patients to prevent tuberculosis infection. Corticosteroid pulse dose should be avoided in SLE patients and if it is needed, tuberculosis prophylaxis may be considered.

Infection-related hospitalization after intensive immunosuppressive therapy among lupus nephritis and ANCA glomerulonephritis patients

Introduction: This study aimed to investigate the clinical characteristics, risk factors, and outcomes of infection-related hospitalization (IRH) in patients with lupus nephritis (LN) and ANCA glomerulonephritis after intensive immunosuppressive therapy.Methods: Patients diagnosed with LN or ANCA glomerulonephritis who received intensive immunosuppressive therapy at the First Affiliated Hospital of Sun Yat-sen University from 2005 to 2014 were enrolled. Demographics, laboratory parameters, immunosuppressive agents, and IRH details were collected. Multivariable Cox regression was used, and hazard ratios (HRs) and 95% confidence intervals (CIs) were reported.Results: Totally, 872 patients with 806 LN and 66 ANCA glomerulonephritis were enrolled, and 304 (34.9%) patients with 433 episodes of IRH were recorded. ANCA glomerulonephritis patients were more vulnerable to IRH than LN patients (53.0% vs. 33.4%, p = .001). Multivariable Cox regression analysis showed that ANCA glomerulonephritis (HR = 1.62, 95% CI: 1.06-2.49, p = .027), diabetes (HR = 1.82, 95% CI: 1.03-3.22, p = .039) and a higher initial dose of prednisone (HR = 1.01, 95% CI: 1.00-1.02, p = .013) were associated with a higher likelihood of IRH. Higher albumin (HR = 0.96, 95% CI: 0.94-0.98, p < .001), globulin (HR = 0.98, 95% CI: 0.96-0.99, p = .008), and eGFR (HR = 0.99, 95% CI: 0.99-1.00, p < .001), were associated with a lower likelihood of IRH. The rates of transfer to ICU and mortality for ANCA glomerulonephritis patients were higher than those for LN patients (22.9% vs. 1.9%, p < .001, and 20.0% vs. 0.7%, p < .001, respectively).Conclusions: ANCA glomerulonephritis patients had a higher risk of IRH and poorer outcome once infected after intensive immunosuppressive therapy than LN patients. More strict control for infection risks is required for ANCA glomerulonephritis patients who undergo intensive immunosuppressive therapy.

Bacterial infections in lupus: Roles in promoting immune activation and in pathogenesis of the disease

BACKGROUND

Bacterial infections of the lung, skin, bloodstream and other tissues are common in patients with systemic lupus erythematosus (lupus) and are often more severe and invasive than similar infections in control populations. A variety of studies have explored the changes in bacterial abundance in lupus patients, the rates of infection and the influence of particular bacterial species on disease progression, using both human patient samples and mouse models of lupus.

OBJECTIVE

The aim of this review is to summarize human and mouse studies that describe changes in the bacterial microbiome in lupus, the role of a leaky gut in stimulating inflammation, identification of specific bacterial species associated with lupus, and the potential roles of certain common bacterial infections in promoting lupus progression.

METHODS

Information was collected using searches of the Pubmed database for articles relevant to bacterial infections in lupus and to microbiome changes associated with lupus.

RESULTS

The reviewed studies demonstrate significant changes in the bacterial microbiome of lupus patients as compared to control subjects and in lupus-prone mice compared to control mice. Furthermore, there is evidence supporting the existence of a leaky gut in lupus patients and in lupus-prone mice. This leaky gut may allow live bacteria or bacterial components to enter the circulation and cause inflammation. Invasive bacterial infections are more common and often more severe in lupus patients. These include infections caused by Staphylococcus aureus, Salmonella enterica, Escherichia coli, Streptococcus pneumoniae and mycobacteria. These bacterial infections can trigger increased immune activation and inflammation, potentially stimulating activation of autoreactive lymphocytes and leading to worsening of lupus symptoms.

CONCLUSIONS

Together, the evidence suggests that lupus predisposes to infection, while infection may trigger worsening lupus, leading to a feedback loop that may reinforce autoimmune symptoms.

Nocardiosis in glomerular disease patients with immunosuppressive therapy

Background

Glomerular disease patients have a high risk of infection, which contributes to the progression of disease per se and mortality, especially in those with long-term use of glucocorticoids and (or) immunosuppressive agents. Cases of sporadic nocardiosis have been reported in glomerular disease patients, and this observation was conducted to comprehensively understand the manifestations of and treatments for nocardiosis, which is commonly misdiagnosed as pneumonia or tuberculosis or even as lung cancer or metastatic tumors in glomerular disease patients.

Methods

We reviewed the demographic characteristics, laboratory abnormalities, radiological features, and treatments of 7 patients with nocardiosis and glomerular disease receiving steroids and immunosuppression therapy at the nephrology department of the Second Xiangya Hospital between 2012 and 2019.

Results

It was found that all 7 patients had been receiving methylprednisolone for renal disease at a median dose of 20 mg per day and a median duration of 4 months before developing nocardiosis. There were 4 males and 3 females, and the median age was 52.14 years. All 7 patients had hypoalbuminemia at the time of admission. In addition, various cystic abscesses in the subcutaneous tissue, with or without lung and brain involvement, were observed in these patients. Encouragingly, body temperatures returned to normal, and subcutaneous abscesses diminished or disappeared with compound sulfamethoxazole treatment alone or in combination with linezolid, imipenem and mezlocillin/sulbactam.

Conclusions

It was shown that multisite abscesses, including subcutaneous, pulmonary and cerebral abscesses, were the common manifestations of nocardiosis in glomerular disease patients. Sulfonamide was the first-line antibiotic therapy for nocardiosis, and combinations of other antibiotics were also needed in some serious cases.

Mortality risk prediction in lupus patients complicated with invasive infection in the emergency department: LUPHAS score

Background:

Infection remains a major cause of morbidity and mortality in patients with systemic lupus erythematosus (SLE). This study aimed to establish a clinical prediction model for the 3-month all-cause mortality of invasive infection events in patients with SLE in the emergency department.

Methods:

SLE patients complicated with invasive infection admitted into the emergency department were included in this study. Patient’s demographic, clinical, and laboratory characteristics on admission were retrospectively collected as baseline data and compared between the deceased and the survivors. Independent predictors were identified by multivariable logistic regression analysis. A prediction model for all-cause mortality was established and evaluated by receiver operating characteristic (ROC) curve analysis.

Results:

A total of 130 eligible patients were collected with a cumulative 38.5% 3-month mortality. Lymphocyte count <800/ul, urea >7.6mmol/l, maximum prednisone dose in the past ⩾60 mg/d, quick Sequential Organ Failure Assessment (qSOFA) score, and age at baseline were independent predictors for all-cause mortality (LUPHAS). In contrast, a history of hydroxychloroquine use was protective. In a combined, odds ratio-weighted LUPHAS scoring system (score 3–22), patients were categorized to three groups: low-risk (score 3–9), medium-risk (score 10–15), and high-risk (score 16–22), with mortalities of 4.9% (2/41), 45.9% (28/61), and 78.3% (18/23) respectively. ROC curve analysis indicated that a LUPHAS score could effectively predict all-cause mortality [area under the curve (AUC) = 0.86, CI 95% 0.79–0.92]. In addition, LUPHAS score performed better than the qSOFA score alone (AUC = 0.69, CI 95% 0.59–0.78), or CURB-65 score (AUC = 0.69, CI 95% 0.59–0.80) in the subgroup of lung infections (n = 108).

Conclusions:

Based on a large emergency cohort of lupus patients complicated with invasive infection, the LUPHAS score was established to predict the short-term all-cause mortality, which could be a promising applicable tool for risk stratification in clinical practice.

Cytomegalovirus infection in Systemic Lupus Erythematosus: report of four cases challenging the management of the disease, and literature review

Cytomegalovirus (CMV) is particularly dangerous in systemic lupus erythematosus (SLE), being a problem both for the differential diagnosis with disease flare and for the management of SLE flare with immunosuppressive drugs. We report on four cases of SLE with concomitant CMV infection, having some common clinical and laboratory characteristics. Our data suggest that lupus patients presenting with symptoms such as fever, diarrhea, and respiratory symptoms, alone or in combination, and laboratory evidence of leukopenia, elevated transaminases, and hyponatremia, especially in the setting of recent immunosuppressive treatments, should be screened for CMV.