Comparison of plasma/serum levels of procalcitonin between infection and febrile disease flare in patients with systemic lupus erythematosus: a meta-analysis

Infection versus disease activity in systemic lupus erythematosus patients with fever

BACKGROUND

to detect the role of procalcitonin, erythrocyte sedimentation rate to c-reactive protein (ESR/CRP) ratio, neutrophils-to-lymphocyte ratio (NLR), and platelets-to-lymphocyte ratio (PLR) in the diagnosis of infection in systemic lupus erythematosus (SLE) patients with fever, their diagnostic value to differentiate between infection and disease activity, and their correlation with disease activity.

METHODS

Forty SLE patients and forty healthy control cases were included in the study. Disease activity was assessed by the Systemic Lupus Erythematosus Disease Activity Index 2000 (SLEDAI-2 K), and quality of life was assessed by Lupus QoL. A bacterial infection was detected by clinical symptoms and positive culture results. Laboratory tests were done for all patients and controls: complete blood count (CBC), ESR, CRP, and procalcitonin (PCT). NLR, PLR, and ESR/CRP ratios were calculated.

RESULTS

There was a statistically significant difference between infected SLE patients and non-infected SLE patients regarding PCT (p < 0.001), ESR (p = 0.002), CRP (p = 0.005), ESR/CRP ratio (0.002), and NLR (p = 0.023). PCT, ESR, CRP, and NLR were positively correlated with the presence of infection in SLE patients, while the ESR/CRP ratio was negatively correlated. There was no significant correlation with the SLEDAI-2 K score. Logistic regression analysis revealed that PCT was the best significant predictor of infection (OR 224.37, 95% CI 8.94-5631.35). PCT was a good predictor of infection, with a cut-off value of 0.90 ng/ml, which gave the best combination of sensitivity (84.62%) and specificity (85.71%).

CONCLUSION

PCT, ESR/CRP ratio, and NLR provide good diagnostic markers for the diagnosis of infection and can distinguish between infection and disease flare in SLE patients with fever.

Procalcitonin for the early discrimination of fever etiology in patients with systemic autoimmune diseases attending the emergency department

In febrile patients with known systemic autoimmune disease, early discrimination between infection and disease flare often represents a clinical challenge. This study aimed at evaluating the efficacy of procalcitonin (PCT) and other common inflammatory biomarkers in discriminating disease flare from bacterial infections in the Emergency Department (ED). In a cross-sectional observational retrospective study, we identified consecutive febrile patients with a known diagnosis of systemic autoimmune disease, admitted to the ED, and subsequently hospitalized. Flare vs infective disease was defined on clinical records at hospital discharge. Dosage of common inflammatory markers was performed at ED admission. Out of 177 patients, those with infection were most commonly elderly, frail, and with reduced peripheral oxygen saturation at admission. When compared to C-reactive protein (CRP) and white blood count (WBC), PCT showed the best performance in discriminating infections vs flare. However, only at a very high threshold value of 2 ng/ml, the PCT had a satisfactory negative predictive value of 88.9%, although with a very low specificity of 13.6% and a positive predictive value of 35.8%. Our data suggest that in the ED setting, the early PCT determination has low accuracy in the differentiation of disease flare from infection in patients with known rheumatologic disease. However, the PCT could be useful in elderly and comorbid subjects, in supporting clinical assessment and in recognizing those febrile patients needing prompt antibiotic treatment.

Mycobacterium xenopi related spine infections: A case report and systematic literature review

Background and purpose

Nontuberculous mycobacteria (NTM) disease is an important infection disease throughout the world. Mycobacterium xenopi (M. xenopi) is a common NTM. Extrapulmonary infections due to M. xenopi, particularly spine infections, are a rare occurrence, but lack of research is cited as a constraint for implementing NTM control in such patients. The purposes of this paper are to describe a case of spondylodiscitis, to review the published literature on cases of M. xenopi spine infections, and to summarize the predisposing factors, diagnosis, and treatment of infection.

Methods

A case of spondylodiscitis was caused by M. xenopi in a patient with systemic lupus erythematosus (SLE). Research was conducted using the PubMed, ScienceDirect, Embase, Wiley Online Library, and Scopus databases using the following search terms: "Mycobacterium xenopi", "vertebral", "spinal", "spondylodiscitis", "infection", and "osteomyelitis".

Results

We retrieved 14 cases published before August 2022. The risk factors for infection were iatrogenic infections (3/14, 21.43%), SLE (4/14, 28.57%), AIDS (4/14, 28.57%), and immunocompetence without any comorbidities (3/14, 21.43%). The most common sites of infection were thoracic vertebrae (10/14, 71.43%) and lumbar vertebrae (4/14, 28.57%). A total of 14 cases were isolated and identified as M. xenopi from a toad by mycobacterial culture. The identification time was 55.00 ± 7.55 days (the present report identification time of metagenomic next generation sequencing (mNGS) was only 2 days). All patients were treated with antibiotic therapy, and the duration of treatment was 13.18 ± 2.13 months. Clarithromycin-based therapy showed a higher improvement rate (5/6, 83.33%). Surgical intervention was performed in 5 patients. Only 1 patient did not show any improvement after surgical treatment.

Conclusion

M. xenopi spine infection in humans presents with atypical clinical symptoms. mNGS identification may be a good choice. M. xenopi may be considered in immunocompromised patients with spinal infection. We recommend a clarithromycin-containing regimen and prolonging the duration of treatment to ensure effectiveness.

Evaluation of the Therapeutic Potential of Mesenchymal Stem Cells (MSCs) in Preclinical Models of Autoimmune Diseases

Autoimmune diseases, chronic in nature, are generally hard to alleviate. Present long-term treatments with available drugs such as steroids, immune-suppressive drugs, or antibodies have several debilitating side effects. Therefore, new treatment options are urgently needed. Stem cells, in general, have the potential to reduce immune-mediated damage through immunomodulation and T cell regulation (T regs) by inhibiting the proliferation of dendritic cells and T and B cells and reducing inflammation through the generation of immunosuppressive biomolecules like interleukin 10 (IL-10), transforming growth factor-β (TGF-β), nitric oxide (NO), indoleamine 2,3-dioxygenase (IDO), and prostaglandin E2 (PGE2). Many stem cell-based therapeutics have been evaluated in the clinic, but the overall clinical outcomes in terms of efficacy and the longevity of therapeutic benefits seem to be variable and inconsistent with the postulated benefits. This emphasizes a greater need for building robust preclinical models and models that can better predict the clinical translation of stem cell-based therapeutics. Stem cell therapy based on MSCs having the definitive potential to regulate the immune system and control inflammation is emerging as a promising tool for the treatment of autoimmune disorders while promoting tissue regeneration. MSCs, derived from bone marrow, umbilical cord, and adipose tissue, have been shown to be highly immunomodulatory and anti-inflammatory and shown to enhance tissue repair and regeneration in preclinical models as well as in clinical settings. In this article, a review on the status of MSC-based preclinical disease models with emphasis on understanding disease mechanisms in chronic inflammatory disorders caused by exaggerated host immune response in rheumatoid arthritis (RA) and systemic lupus erythematosus (SLE) was carried out. We also emphasized various factors that better predict the translation of stem cell therapeutic outcomes from preclinical disease models to human patients.

Differentiating flare and infection in febrile lupus patients: Derivation and validation of a calculator for resource constrained settings

Background: Patients with Systemic Lupus Erythematous (SLE) are at an increased risk of infection and it is often difficult to differentiate between infection and disease activity in a febrile patient with SLE. Methods: Patients with SLE (SLICC criteria) presenting with fever between December 2018 and August 2021 were included. Neutrophil to lymphocyte ratio (NLR), NEUT-x, -y, -z indices, Erythrocyte sedimentation rate (ESR), C-reactive protein(CRP), C3, C4, anti-dsDNA antibodies, and procalcitonin(PCT) were tested in addition to investigations as per the treating physician's discretion. Based on the clinical assessment and laboratory data, the febrile episode was classified into infection, disease flare, or both. Statistical analysis was done using GraphPad prism v8.4.2. A novel composite score was devised and validated with a calculator incorporated is a spreadsheet. The performance of a previously proposed model of duration of fever, CRP, and dsDNA (Beca et al) was evaluated and other models using PCT and NEUT-Z were explored. Results: Among 168 febrile episodes in 166 patients with SLE (25 (19-32) years), 46 were due to infection, 77 due to flare, 43 due to both, and two due to other causes. High SLEDAI 2K (0.001), anti-dsDNA (p = 0.004), and low complements(C3, p = 0.001 and C4, p = 0.001) were characteristic of disease flare, whereas high total leukocyte count (TLC) (p = 0.008), NLR (p = 0.008), NEUT-x (p = 0.001), -y (p = 0.03), -z (p = 0.002), CRP (p = 0.001), and PCT (p = 0.03) were observed with infection. A model using age, TLC, and CRP was devised using 80% of the cohort with an AUC of 0.88 (0.78-0.97) which was validated in the remaining 20% to have an AUC of 0.83(0.60-1.0). The model devised by Beca et al yielded an AUC of 0.74. Use of PCT did not improve the discrimination between flare and infection. A Model of C4 and NEUT-z analyzed in a subset performed well and needs further exploration. Conclusion: A composite score of low cost and routinely available parameters like age, TLC, and CRP gives a good discrimination between infection and flare in a febrile patient with SLE.

The utility of erythrocyte sedimentation rate, C-reactive protein, and procalcitonin in detecting infections in patients with systemic lupus erythematosus: A systematic review

OBJECTIVES

We conducted a systematic review with metanalysis to investigate the utility of erythrocyte sedimentation rate (ESR), C-reactive protein (CRP), and procalcitonin (PCT) in diagnosing infections in hospitalized patients with SLE.

METHODS

We searched Medline, Embase, Web of Science, ClinicalTrials.gov, and Cochrane Central Register of Controlled Trials (CENTRAL) with a search strategy developed by a medical librarian. We included retrospective, cross-sectional, case-control, and prospective studies in our analysis. We used the Quality Assessment of Diagnostic Studies (QUADAS-2) to assess for bias and applicability. We obtained mean differences, sensitivities, and specificities in our analysis.

RESULTS

We included 26 studies in our analysis. Most studies had an unclear or high risk of bias and our results were widely heterogenous. For the diagnosis of infections, the CRP had a pooled sensitivity of 0.75 (95%CI 0.57-0.94) and specificity of 0.72 (0.59-0.85), PCT had a pooled sensitivity of 0.68 (95% CI 0.0.59-0.77) and specificity of 0.75 (0.59-0.90), and for ESR pooled estimates were not calculated but sensitivity ranged from 50 to 69.8 and specificity from 38.5 to 55.6. Modifying cut-offs improved sensitivities and specificities. The ESR, CRP, and PCT mean differences were all greater in infection groups versus non-infection (10.1, 95% CI 3.2-17.0; 46.8, 95% CI 36.5-57.0; 0.53, 95% CI 0.26-0.80; respectively).

DISCUSSION

Poor sensitivities and specificities were observed for the evaluated biomarkers with substantial heterogeneity in the cut-offs used to determine infection. Although mean biomarker values were increased in the infection group compared with the non-infection, our findings do not support the widespread use of ESR, CRP, or PCT in diagnosing infection in hospitalized patients with SLE due to increased heterogeneity and risk of bias. Further investigation is needed.

Infection in Hospitalized Patients With Systemic Lupus Erythematosus: Proposal of an Algorithm for Diagnosis

BACKGROUND

Identification of infection in patients with systemic lupus erythematosus (SLE) is a major challenge in clinical practice.

OBJECTIVE

This medical records review study evaluated clinical markers, including the performance of C-reactive protein (CRP), neutrophil-lymphocyte ratio (NLR), and platelet-lymphocyte ratio (PLR) in the diagnosis of infection in SLE patients.

METHODS

One hundred four SLE patients hospitalized between 2014 and 2018 were allocated into 3 groups, namely, infection, infection and disease activity, and isolated disease activity. Groups were compared in relation to clinical and laboratory variables. Accuracy measures were calculated for CRP, NLR, and PLR.

RESULTS

C-reactive protein, NLR, and PLR differed between the groups with higher values observed in the infected group, intermediate values in the mixed group, and lower values in the group with isolated activity-CRP (56 vs 26 vs 15 mg/dL, p = 0.002), NLR (7.9 vs 4.0 vs 3.1, p = 0.005), and PLR (270 vs 227 vs 134, p = 0.025). Fever, tachypnea, and PLR were independently associated with infection. The cutoff points of the CRP of 20 mg/L, NLR of 3.5, and PLR of 151.4 presented values of sensitivity and specificity for the prediction of infection equal to 67% and 67%, 65% and 58%, and 71% and 53%, respectively. The developed algorithm showed a sensitivity of 86.6% and specificity of 81% for the diagnosis of infection.

CONCLUSIONS

The combined use of clinical and laboratory markers presented superior accuracy than their isolated use, suggesting a great potential for the application of the algorithm in clinical practice.

Tocilizumab therapy for persistent high-grade fever in systemic lupus erythematosus: two cases and a literature review

Tocilizumab (TCZ) is a humanized immunoglobulin (Ig) G1 monoclonal antibody directed against the interleukin (IL)-6 receptor. We report on two patients with persistent high-grade fever and systemic lupus erythematosus (SLE) who were treated with TCZ. Two female Chinese patients presented with SLE and high-grade fever, with raised inflammatory markers including C-reactive protein, erythrocyte sedimentation rate, and IL-6, but no signs of opportunistic infections. Their fever and other symptoms responded poorly to broad-spectrum antibiotics, antifungals, antivirals, and glucocorticoids. They were both treated with TCZ. Their body temperatures returned to normal after treatment with TCZ, and other symptoms, including arthralgia, gradually improved. Both patients were followed-up and their conditions remained steady to date. TCZ may thus be an alternative treatment for patients with SLE and persistent high-grade fever who fail to respond to initial antibiotics and high-dose glucocorticoids.

Serum procalcitonin and C-reactive protein levels as diagnostic markers for distinguishing bacterial infections from lupus flares in systemic lupus erythematosus: A systematic review and meta‑analysis

PURPOSE

To systematically evaluate the diagnostic performance of procalcitonin (PCT) and C-reactive protein (CRP) for distinguishing bacterial infections from lupus flares in systemic lupus erythematosus (SLE) via meta-analysis.

METHODS

Electronic databases were comprehensively searched. The pooled standard mean difference (SMD) and 95% confidence interval (CI) were calculated to estimate the differences of serum PCT and CRP levels between bacterial infections and flares in SLE. Sensitivity, specificity and summary receiver operating characteristics (SROC) curve were used to assess the diagnostic values of PCT and CRP. The use of fixed or random effects model depended on heterogeneity.

RESULTS

Fifteen studies were included in the analysis. Serum PCT and CRP levels were significantly higher in SLE patients with bacterial infections compared to SLE patients with flares (PCT: SMD = 1.035, 95 %CI = 0.708 to 1.362; CRP: SMD = 1.000, 95 %CI = 0.758 to 1.242). The overall sensitivity, specificity, area under the SROC curve, positive likelihood ratios (PLR) and negative likelihood ratios (NLR) of PCT were 0.62, 0.88, 0.862, 6.63 and 0.36, respectively, while the same indicators for CRP were 0.72, 0.70, 0.784, 2.45 and 0.38, respectively.

CONCLUSION

Serum PCT and CRP levels were significantly increased in SLE with bacterial infections. PCT had a better diagnostic performance than CRP. PCT had a high value of PLR and could serve as a rule-in marker, while CRP testing may result in a high false-positive rate due to low PLR; both markers had a suboptimal value of NLR and are not appropriate for ruling out bacterial infections.

Evaluation of serum presepsin, procalcitonin, copeptin, and high-sensitivity C-reactive protein for differentiating bacterial infection from disease activity in Egyptian patients with systemic lupus erythematosus

OBJECTIVES

Several biological markers have been studied for the differentiation of infection from disease activity in systemic lupus erythematosus (SLE) patients with discrepant results. We aimed to evaluate the role of serum presepsin, hs-CRP, procalcitonin (PCT), and copeptin (CPP) in differentiating bacterial infections from disease activity in SLE patients.

METHODS

This study is a cross-sectional observational study in which 94 Egyptian patients were recruited from June 2017 to January 2018. Our patients were divided into two groups: group (1) included 48 patients with active SLE hospitalized with any sort of lupus activity and group (2) included 46 patients with active SLE admitted with a proven bacterial infection. Hs-CRP, presepsin, PCT, and CPP were measured using enzyme-linked immune sorbent assay technique.

RESULTS

Hs-CRP, presepsin, PCT, and CPP were highly significantly higher among group (2) patients compared to group (1) patients (p < 0.001). Serum presepsin expressed higher specificity than hs-CRP (87.5% vs 60.4%) but the same sensitivity (80.4%) in the detection of bacterial infection in SLE patients. Serum PCT expressed higher specificity than hs-CRP (100% vs 60.4%) but lower sensitivity (73.9% vs 80.4%). Serum CPP expressed higher specificity than hs-CRP (65.9% vs 60.4%) but lower sensitivity (65.9% vs 80.4%).

CONCLUSION

Our study suggests that increased serum levels of hs-CRP, presepsin and PCT levels are useful in differentiating bacterial infections from disease activity in SLE patients. Serum CPP could be used as an adjunct with more specific inflammatory biomarkers in making better diagnostic judgments.

KEY POINTS

• The increased serum levels of hs-CRP, presepsin and PCT levels are useful in differentiating bacterial infections from disease activity in SLE patients. • Serum Presepsin expressed higher specificity than hs-CRP but the same sensitivity in the detection of bacterial infection in SLE patients. • Serum CPP expressed higher specificity than hs-CRP but lower sensitivity.

Infections in hospitalized children with newly diagnosed systemic lupus erythematosus in underresourced areas

Background

The administration of induction immunosuppressive therapy to children with newly diagnosed systemic lupus erythematosus (SLE) and concurrent infections can lead to unfavourable outcomes. This study was conducted to describe characteristics of infections occurring before the initiation of immunosuppressants in hospitalized children with newly diagnosed SLE in underresourced areas.

Methods

Medical records of paediatric patients with the diagnosis of SLE, who were admitted to a university-based hospital from 2002 to 2018, were reviewed. Only patients younger than 18 years of age with newly diagnosed SLE were included in the study. The primary outcome was infection before the administration of immunosuppressants. Logistic regression analysis was used to determine factors associated with infection and adjusted odds ratio (OR). The diagnostic accuracy of CRP was assessed.

Results

Infections were confirmed in 52/124 (41.9%) children. Pathogens were identified in 24 (46.2%) patients with bacterial predominance. The most common site was respiratory infections (36.5%). Fever and serosal involvement were more prevalent in patients with infection. Serum CRP levels were significantly higher in patients with infection than in those without infection (median 5.5 mg/L (interquartile range (IQR) 3.6–76.3 mg/L) vs. 3.5 mg/L (IQR 3.0–3.6 mg/L), p = 0.004). When a positive CRP level of >5 mg/L was used, positive CRP was found with a higher prevalence in patients with infection and was independently associated with infection (adjusted odds ratio (OR) = 28.6, 95% confidence interval (CI) 2.3–350.6; p = 0.009). Patients with infection had a longer hospital stay than patients without infection (median 20 days (IQR 13–25 days) vs. 15 days (IQR 9–24 days), p = 0.04). Sensitivity, specificity, positive predictive value and negative predictive value with 95% CI of CRP >5 mg/L were 62.5% (35.4–84.8%), 88.9% (65.3–98.6%), 80.3% (51.0–94.1%) and 76.6% (63.1–86.3%), respectively.

Conclusions

Infections were common among hospitalized children with newly diagnosed SLE. Children with infections had a prolonged course of hospitalization. Positive CRP was associated with a predisposition towards infection. However, the diagnostic accuracy of CRP requires further validation in a larger study.

Clinical characteristics and prognostic risk factors of anti-neutrophil cytoplasmic antibody (ANCA)-associated vasculitides (AAV)

OBJECTIVE

The complement alternative pathway is involved in the development of AVV. Several studies showed that AVV patients with low serum complement C3 (sC3) levels tend to have a poor prognosis. The aim of this study was to determine whether low sC3 measured at AAV onset is a risk factor for survival prognosis in patients with AVV, and further identified other potential risk factors for predicting patient survival prognosis.

METHODS

A retrospective analysis of 52 newly onset AAV patients was performed. The clinical parameters of the AAV patients were collected. The laboratory parameters before immunosuppressive treatment were evaluated. According to the level of sC3, the patients were divided into low sC3 group (n = 19) and normal sC3 group (n = 33). Disease outcome measures included end-stage renal disease (ESRD) or death. The clinical parameters and survival rate between the two groups were compared. Spearson correlation analysis was used to analyze the correlation between sC3 and other laboratory parameters.

RESULTS

Significant differences were found regarding Birmingham Vasculitis Activity Score (BVAS), sC3, sC4, lactate dehydrogenase, blood urea nitrogen, procalcitonin (PCT), and estimated glomerular filtration rate (eGFR) between the two groups (p = 0.006, 0.000, 0.001, 0.049, 0.019, 0.000 and 0.045, respectively). The survival rate of the low sC3 group was significantly lower than that of the normal sC3 group (Log Rank Chi-square = 4.416, P = 0.036). Low sC3 was significantly associated with lower sC4 (r = 0.570, P = 0.000), lower serum albumin (r = 0.311, P = 0.025), lower eGFR (r = 0.289, P = 0.037), higher PCT (r = -0.566, P = 0.000), and higher lactate dehydrogenase (r = -0.323, P = 0.019).

CONCLUSION

This retrospective study demonstrates that AAV patients with low sC3 level at diagnosis tend to have lower baseline eGFR and poorer survival prognosis than those of the normal sC3 level. Furthermore, the high procalcitonin (PCT), low serum albumin and high lactate dehydrogenase in AVV patients may be predictors of poor prognosis.

[Procalcitonin in the intensive care unit : Differential diagnostic and differential therapeutic possibilities]

Prokalzitonin (PCT) wird bei systemischen Inflammationszuständen IL6-, IL8- und TNF-α-vermittelt in multiplen Organen und Strukturen des Körpers gebildet. Dabei werden insbesondere bei der Sepsis deutlich erhöhte Werte gemessen. Die Höhe des PCT korreliert dabei gut mit der Krankheitsschwere, ein signifikanter Abfall unter Therapie mit der Prognose. In der differenzialdiagnostischen Abklärung kann die PCT-Bestimmung zwischen bakteriellen und viralen Infektionen unterscheiden. Nichtinfektiösbedingte inflammatorische Reaktionen können jedoch moderat erhöhte PCT-Werte zeigen. Cut-off-Werte sind abhängig von der renalen und hepatischen Funktion. Ein Therapiealgorithmus zur Antibiotikadauer mit PCT-Verlaufsbestimmungen kann den Antibiotikagebrauch reduzieren. In dieser Arbeit sollen die differenzialdiagnostischen und differenzialtherapeutischen Möglichkeiten einer Prokalzitoninbestimmung bei kritisch kranken Patienten erörtert werden.

[Fever in systemic lupus erythematosus: disease exacerbation or infection?]

The differential diagnosis of fever, especially in the context of autoimmune diseases is broad. Accordingly, the spectrum of diagnostic procedures is extensive and the therapeutic consequences are partly contradictory. Fever is basically the manifestation of an increased cell proliferation, such as classically seen in tumors, infections or autoimmune inflammation. Systemic lupus erythematosus (SLE) is one of the most multifaceted rheumatological diseases. Fever is one component of the new classification criteria which help to classify and possibly diagnose SLE. The differential work-up of fever is a special challenge for clinicians particularly in the context of the initial diagnosis of SLE or another autoimmune disease and also in the course of the disease in patients with autoimmune diseases. Based on a case report this article discusses differential diagnostic considerations and proposes a concrete differential diagnostic procedure. The patient's history is highlighted as an extremely important source of relevant information. Without claiming completeness various factors are listed, which help to differentiate fever as a consequence of SLE activity versus fever as a consequence of an infection.

Clinical Efficacy and Safety of Mesenchymal Stem Cells for Systemic Lupus Erythematosus

Systemic lupus erythematosus (SLE) is a polymorphic, multisystemic autoimmune disease that causes multiorgan damage in which cellular communication occurs through the involvement of autoantibodies directed against autoantigen production. Mesenchymal stem cells (MSCs), which have strong protective and immunomodulatory abilities, are obtained not only from bone marrow but also from medical waste such as adipose tissue and umbilical cord tissue and have been recognized as a promising tool for the treatment of various autoimmune diseases and inflammatory disorders. This meta-analysis is aimed at assessing whether MSCs can become a new treatment for SLE with good efficacy and safety. Based on predetermined criteria, a bibliographical search was performed from January 1, 2000, to July 31, 2019, by searching the following databases: ISI Web of Science, Embase, PubMed, the Cochrane Library, and the Chinese Biomedical Literature Database (CBM). Eligible studies and data were identified. Statistical analysis was conducted to assess the efficacy (proteinuria, systemic lupus erythematosus disease activity index (SLEDAI), Scr, BUN, albumin, C3, and C4) and safety (rate of adverse events) of MSCs for SLE using Cochrane Review Manager Version 5.3. Ten studies fulfilled the inclusion criteria and were eligible for this meta-analysis, which comprised 8 prospective or retrospective case series and four randomized controlled trails (RCTs) studies. In the RCT, the results indicated that the MSC group had lower proteinuria than the control group at 3 months and 6 months and the MSC group displayed a lower SLEDAI than the control group at 2 months and 6 months. Furthermore, the MSC group showed a lower rate of adverse events than the control group (OR = 0.26, 95% CI: 0.07, 0.89, P = 0.03). In the case series trials, the results indicated that the MSC group had lower proteinuria at 1 month, 2 months, 3 months, 4 months, 6 months, and 12 months. In conclusion, MSCs might be a promising therapeutic agent for patients with SLE.

Risk factors of infection-associated mortality in children with lupus nephritis in under-resourced areas

INTRODUCTION

Treatment of lupus nephritis class III, IV and V with immunosuppressive therapy increases patient survival but poses a risk of infection-related mortality. This study was conducted to evaluate risk factors for fatal infection in children with lupus nephritis in under-resourced areas.

METHODS

Medical records of patients, who were admitted to a tertiary-care university-based hospital from January 2002 to July 2018 with the diagnosis of systemic lupus erythematosus, were reviewed. Only patients aged less than 18 years with lupus nephritis and documented infection were included in the study. The primary outcome was infection-associated mortality. The logistic regression model was used to identify independent variables associated with fatal infection. Predicted probabilities of infection-related mortality adjusted for factors significant in multivariate analysis were calculated using marginal effects at representative values.

RESULTS

Infection-related deaths occurred in 27 of 179 patients (15.1%). Hospital-acquired infections occurred in 72 of 375 episodes of hospital admissions (19.2%) and 13 hospital-acquired infections (18.1%) resulted in fatal infection. Invasive fungal infections were the leading cause of death (44.4%) and pulmonary infections were the predominant site (55.5%). Haemoglobin levels and glomerular filtration rates were significantly lower in deceased versus surviving patients. Percentages of patients with hospital-acquired infections, invasive fungal infections and pulmonary infections were significantly higher in deceased than surviving patients. Urine protein, the neutrophil-to-lymphocyte ratio, cumulative methylprednisolone dose and daily prednisolone dose were significantly higher in deceased than surviving patients. In multivariate analysis, a neutrophil-to-lymphocyte ratio more than 20, invasive fungal infections and high daily prednisolone dose were independently predictive of fatal infection with adjusted odds ratio of 3.02 (95% confidence interval 1.02-8.97, p = 0.04), 15.08 (95% confidence interval 4.72-48.24, p < 0.001) and 1.03 (95% confidence interval 1.01-1.06, p = 0.04), respectively. A high daily prednisolone dose intensified the impact of invasive fungal infections and high neutrophil-to-lymphocyte ratio on predicted probability of infection-associated mortality.

CONCLUSIONS

Prevention of invasive fungal infections and minimization of daily prednisolone should be emphasized in routine clinical practice of children with lupus nephritis in under-resourced areas to achieve better survival. Children with lupus nephritis and a high neutrophil-to-lymphocyte ratio should be under cautious surveillance for infection.

The diagnostic values of C-reactive protein and procalcitonin in identifying systemic lupus erythematosus infection and disease activity

To explore the values of C-reactive protein (CRP) and procalcitonin (PCT) in identifying infection and disease activity in systemic lupus erythematosus (SLE) patients.Patients with SLE and infection from April 2015 to January 2018 were included in this study. We compared the clinical characteristics and biomarkers between different groups and calculated the receiver operating characteristic curve, sensitivity, and specificity of the corresponding biomarkers. Logistic regression analysis was performed on the variables exhibiting significant differences in univariate analysis.A total of 177 SLE patients were retrospectively analyzed. The patients were divided into noninfected-inactive group, noninfected-active group, infected-inactive group, and infected-active group. CRP level of infected-inactive group was significantly higher than noninfected-inactive group (P < .05), but not significantly in infected-active group than noninfected-active group (P > .05). Multivariate analysis showed that CRP (>24.0 mg/L) was the only independent risk factor for SLE infection (odds ratio, OR = 2.896, P = .032). PCT level of infected-active group was significantly higher than infected-inactive group (P < .05), but not significantly in noninfected-active group than noninfected-inactive group (P > .05). SLE active group had shorter disease course, lower infection rate, higher PCT level, and lower platelet count (PLT). Multivariate logistic analysis showed that PCT (>0.048 ng/mL) and PLT (<150 × 10/L) were independent risk factors for SLE activity (OR = 3.498 and 4.391, P = .011 and 0.009), and disease course (>96 months) was independent protective factor (OR = 0.169, P < .001). The area under the curve of the logistic model was significantly larger than any single variable (all P < .05).CRP is the only effective marker for diagnosing infection in SLE patients. Moreover, PCT helps predict SLE activity.

Role of biomarkers in the diagnosis of bacterial infections in rheumatic diseases

In modern rheumatology, the problem of differential diagnosis of bacterial infection and active rheumatic process still retains its relevance. At the same time, it is very important to search for a biomarker - the gold standard for the diagnosis of an infection in patients with rheumatic diseases (RDs) in order to rapidly determine a treatment policy. This review analyzes the diagnostic significance and possibility of using some laboratory markers for bacterial infections in modern rheumatology. It emphasizes the importance of a multimarker approach that allows increasing the significance of individual parameters in the diagnosis of infections in RD.

Autoimmune manifestations of infections

PURPOSE OF REVIEW

To provide an update about the interactions between infections and autoimmune diseases (AIDs), from the molecular perspective to the clinical spectrum and the differentiation between infection and disease activity.

RECENT FINDINGS

Any kind of infection may modify the innate and adaptive immune response through the following mechanisms: molecular mimicry, superantigens, epitope spreading and B-cell activation. The consequence is the overproduction of antibodies shared with those found in AIDs. Viral infections, especially HIV and hepatitis C virus, can stimulate the production of antiphospholipid antibodies and confer an increased risk to develop antiphospholipid syndrome.

SUMMARY

The identification of risk factors to develop infections in patients with AIDs is remarkable to prevent them. These factors are the use of steroids and immunosuppressants, the involvement of a major organ (lungs, brain and kidney) and severe activity. Biomarkers to differentiate infection from disease activity are scarce, but the combination of procalcitonine and C-reactive protein seems to have higher specificity and sensibility to identify infections in patients with AIDs. Finally, the clinical judgment is the hallmark to differentiate between infections and disease activity.

Altered peripheral lymphocyte subsets in untreated systemic lupus erythematosus patients with infections

The leading cause of death in systemic lupus erythematosus (SLE) patients is infection. The objective of this study was to evaluate the distribution of lymphocyte subsets in untreated SLE patients with infections. This was a cross-sectional study. Data from January 2017 to May 2018 were collected. Flow cytometry was used to measure the peripheral lymphocyte subsets including CD3+T cells, CD4+T cells, CD8+T cells, CD19+B cells, CD3-CD16+CD56NK cells, and CD3+CD16+CD56NKT cells in 25 healthy controls and 52 treatment-naive SLE patients, among whom 13 were complicated with infections. Association between the lymphocyte subsets and infections was further analyzed. SLE patients with infections (n=13) showed a significantly higher incidence rate of fever (84.6 vs 28.2%) and serositis (84.6 vs 23.1%), increased level of erythrocyte sedimentation rate (60.5±30.1 vs 37.4±27.1 mm/h), serum C-reactive protein (CRP) (102.7±94.9 vs 9.4±14.9 mg/L), procalcitonin (PCT) (1.07±0.08 vs 0.16±0.13 μg/L), and lower blood hemoglobin (Hb) (93.0±20.5 vs 110.4±16.0 g/L) level compared with non-infection patients (n=39) (all P<0.05). In comparison with non-infectious SLE patients (387.9±261.6/μL), CD4+T cells count decreased significantly in infectious SLE patients (217.8±150.4/μL) (P<0.05), and it was negatively correlated with infection-related indicators including PCT (r=-0.573, P=0.041) and CRP (r=-0.596, P=0.032) levels. Our findings suggested that abnormalities of peripheral lymphocyte subsets were related to the immune disorder of lupus itself, regardless of immunosuppressive treatment. Monitoring lymphocyte subsets, especially CD4+T cells, may be helpful for identifying the presence of infection in SLE patients.

Utility of neutrophil-to-lymphocyte ratio plus C-reactive protein for infection in systemic lupus erythematosus

Distinction between infection and flare in patients with systemic lupus erythematosus (SLE) is a challenge in clinical practice.

Objective

To analyze the utility of neutrophil-to-lymphocyte ratio (NLR) plus C-reactive protein (CRP) to differentiate between infection and active disease in patients with SLE.

Methods

A cross-sectional study of a cohort of patients with SLE was carried out. Blood samples from four groups (patients without infection or active disease, patients with infection, patients with active disease, and patients with both infection and active disease) before therapeutic interventions were analyzed. We excluded patients with current malignancy, pregnancy, ischemic heart disease or use of antimicrobials during previous 7 days. Hematological cell count, CRP and cultures were obtained. We constructed receiver operating characteristic curves; sensitivity, specificity, positive predictive value (PPV) and negative predictive value (NPV) were calculated.

Results

Forty patients were included. NLR cut-off ≥6.3 had sensitivity 70%, specificity 85%, PPV 83% and NPV 74% to detect patients with non-viral infections. A CRP cut-off ≥7.5 mg/L had sensitivity 90%, specificity 75%, PPV 78% and NPV 88% to detect infections regardless of SLE activity. Combination of CRP plus NLR improves the specificity to 90% and PPV to 88%. Excluding the group with both infection and active disease, CRP plus NLR expands specificity to 95% and NPV to 90%.

Conclusion

In our experience, levels of CRP, particularly CRP plus NLR, were useful in differentiating patients with SLE from those with suspected non-viral infection regardless of the activity of the disease.

Procalcitonin as a diagnostic indicator for systemic bacterial infections in patients with Stevens-Johnson syndrome/toxic epidermal necrolysis

Elevated serum procalcitonin (PCT) level has been reported to be a diagnostic index in systemic bacterial infections, but it can also increase in some non-infectious inflammatory diseases. Stevens-Johnson syndrome (SJS)/toxic epidermal necrolysis (TEN) is a rare immune-mediated cutaneous mucosal reaction which is susceptible to bacterial infections and may have elevated PCT levels. The value of serum PCT has not been assessed in series of SJS/TEN patients. We aimed to investigate the PCT levels in SJS/TEN patients with systemic bacterial infections (systemic infected group), with skin surface bacterial infections (skin surface infected group) and without infections (non-infected group), to assess whether PCT was a valuable indicator for systemic bacterial infections in SJS/TEN patients. The PCT and C-reactive protein (CRP) levels of 42 inpatients with SJS/TEN were retrospectively analysis. The receiver-operator curve (ROC) was used to determine the diagnostic efficacy of PCT for systemic bacterial infections in SJS/TEN patients. The results demonstrated that PCT levels in the systemic infected group were significantly higher than those in the other two groups (P < 0.05). There was no significant difference in CRP between the three groups. The cut-off PCT level of 0.65 ng/mL calculated by ROC had optimal diagnostic efficacy, with sensitivity and specificity of 84.6% and 89.7%, respectively. PCT and severity-of-illness score for toxic epidermal necrolysis were positively correlated (P < 0.05). In conclusion, PCT is a valuable index and superior to CRP in detecting systemic bacterial infections in SJS/TEN patients. The level of PCT can partially reflect the severity of the disease.

Procalcitonin and C-reactive protein as markers of infection in systemic lupus erythematosus: the controversy continues

OBJECTIVE

The objective of this paper is to investigate the utility of serum procalcitonin (PCT) and C-reactive protein (CRP) as markers of infection in systemic lupus erythematosus (SLE) patients.

PATIENTS AND METHODS

Sixty-nine SLE patients with symptoms and signs of infection proved by culture and/or a favorable response to antibiotics and 69 SLE patients without infection were included. Serum PCT and plasma high-sensitivity CRP were assessed by an enzyme-linked immunosorbent assay.

RESULTS

SLE patients with infection had a significantly higher level of CRP than those without infection ((median (IQR) 104.5 (25.5-100.9) and 10.3 (5.4-23.1) mg/l, respectively), p<0.001).

CONCLUSION

Serum PCT could not differentiate SLE patients with or without bacterial infection in this study, while the utility of CRP as a marker of infection has been confirmed.