Serum ferritin as a serologic marker of activity in systemic lupus erythematosus

Mendelian Randomization Analysis of Systemic Iron Status and Risk of Different Types of Kidney Disease

With rapid increases in incidence, diverse subtypes, and complicated etiologies, kidney disease remains a global public health problem. Iron, as an essential trace element, has pleiotropic effects on renal function and the progression of kidney diseases. A two-sample Mendelian randomization (MR) analysis was implemented to determine the potential causal effects between systemic iron status on different kidney diseases. Systemic iron status was represented by four iron-related biomarkers: serum iron, ferritin, transferrin saturation (TfSat), and total iron binding capacity (TIBC). For systemic iron status, 163,511, 246,139, 131,471, and 135,430 individuals were included in the genome-wide association study (GWAS) of serum iron, ferritin, TfSat, and TIBC, respectively. For kidney diseases, 653,143 individuals (15,658 cases and 637,485 controls), 657,076 individuals (8160 cases and 648,916 controls), and 659,320 individuals (10,404 cases and 648,916 controls) were included for immunoglobulin A nephropathy (IgAN), acute kidney disease (AKD), and chronic kidney disease (CKD), respectively. Our MR results showed that increased serum iron [odds ratio (OR): 1.10; 95% confidence interval (95% CI): 1.04, 1.16; p < 0.0042], ferritin (OR: 1.30; 95% CI: 1.14, 1.48; p < 0.0042), and TfSat (OR: 1.07; 95% CI: 1.04, 1.11; p < 0.0042)] and decreased TIBC (OR: 0.92; 95% CI: 0.88, 0.97; p < 0.0042) were associated with elevated IgAN risk. However, no significant associations were found between systemic iron status and AKD or CKD. In our MR study, the genetic evidence supports elevated systemic iron status as a causal effect on IgAN, which suggests a potential protective effect of iron chelation on IgAN patients.

Vision-Related Quality of Life in Patients with Systemic Lupus Erythematosus

PURPOSE

To assess vision-related quality of life (VRQoL) in patients with systemic lupus erythematosus (SLE) under treatment with hydroxychloroquine (HCQ), and to find the influencing factors.

METHODS

Cross-sectional study enrolling SLE patients for less than ten years (Group 1), SLE patients for more than ten years (Group 2), and healthy controls (Group 3). SLE patients should be under treatment with HCQ but without ophthalmological affection. Schirmer test, best-corrected visual acuity (BCVA), axial length (AL) with optical biometry, and swept-source optical coherence tomography-angiography (OCTA) Triton (Topcon) were performed. All participants fulfilled the Impact of Visual Impairment questionnaire, and SLE patients answered the Lupus Impact Tracker (LIT) questionnaire. Additional data were obtained from clinical records.

RESULTS

A totals of 41 eyes (41 patients), 31 eyes (31 patients) and 45 eyes (45 volunteers) were enrolled in the study groups. The mean ages were 41.09 ± 9.56, 45.06 ± 8.47 and 40.25 ± 10.83 years, respectively (p = 0.10). The LIT outcomes were 33.49 ± 20.74 and 35.98 ± 22.66 (p = 0.63), respectively. Group 3 referred to a better VRQoL than Group 2 in all categories and than Group 1 in some of them. A linear regression analysis showed that serum ferritin, SLE activity scales, body-mass index (BMI), age, and BCVA influenced VRQoL. The LIT questionnaire was correlated to two categories of the Impact of Visual Impairment questionnaire (IVI).

CONCLUSIONS

Despite no ophthalmological affection, SLE patients refer to poorer VRQoL because of disease activity and a low health-related quality of life, which has a negative influence on VRQoL. This masks the effect of other ophthalmological conditions such as dry eyes. Other variables influencing VRQoL are age and BMI, and BCVA, to a lesser extent.

Expanding the spectrum of the hyperferritinemic syndrome, from pathogenic mechanisms to clinical observations, and therapeutic implications

From the introduction of hyperferritinemic syndrome concept, a growing body of evidence has suggested the role of ferritin as a pathogenic mediator and a relevant clinical feature in the management of patients with inflammatory diseases. From a pathogenic point of view, ferritin may directly stimulate the aberrant immune response by triggering the production of pro-inflammatory mediators in inducing a vicious pathogenic loop and contributing to the occurrence of cytokine storm syndrome. The latter has been recently defined as a clinical picture characterised by elevated circulating cytokine levels, acute systemic inflammatory symptoms, and secondary organ dysfunction beyond that which could be attributed to a normal response to a pathogen It is noteworthy that the occurrence of hyperferritinemia may be correlated with the development of the cytokine storm syndrome in the context of an inflammatory disease. In addition to adult onset Still's disease, macrophage activation syndrome, catastrophic anti-phospholipids syndrome, and septic shock, recent evidence has suggested this association between ferritin and life-threatening evolution in patients with systemic lupus erythematosus, with anti-MDA5 antibodies in the context of poly-dermatomyositis, with severe COVID-19, and with multisystem inflammatory syndrome. The possible underlying common inflammatory mechanisms, associated with hyperferritinemia, may led to the similar clinical picture observed in these patients. Furthermore, similar therapeutic strategies could be suggested inhibiting pro-inflammatory cytokines and improving long-term outcomes in these disorders. Thus, it could be possible to expand the spectrum of the hyperferritinemic syndrome to those diseases burdened by a dreadful clinical picture correlated with hyperferritinemia and the occurrence of the cytokine storm syndrome. In addition, the assessment of ferritin may provide useful information to the physicians in clinical practice to manage these patients. Therefore, ferritin may be considered a relevant clinical feature to be used as biomarker in dissecting the unmet needs in the management of these disorders. Novel evidence may thus support an expansion of the spectrum of the hyperferritinemic syndrome to these diseases burdened by a life-threatening clinical picture correlated with hyperferritinemia and the occurrence of the cytokine storm syndrome.

Cross-sectional study of plasma Axl, ferritin, IGFBP4 and sTNFR2 as biomarkers of disease activity in childhood-onset SLE: A study of the Pediatric Nephrology Research Consortium

OBJECTIVE

To evaluate the performance of 4 plasma protein markers for detecting disease activity in childhood-onset systemic lupus erythematosus (SLE) patients.

METHODS

Eighty-three consecutive pediatric patients fulfilling ≥4 ACR criteria for SLE and twenty-five healthy controls were prospectively recruited for serological testing of 4 protein markers identified by antibody-coated microarray screen, namely Axl, ferritin, IGFBP4 and sTNFR2. SLE disease activity was assessed using SLEDAI-2000 score. Fifty-seven patients had clinically active SLE (SLEDAI score ≥4, or having a flare).

RESULTS

The plasma concentrations of Axl and ferritin were significantly higher in patients with active SLE than inactive SLE. Plasma Axl levels were significantly higher in active renal versus active non-renal SLE patients. Levels of Axl, ferritin and IGFBP4 correlated significantly with SLEDAI scores. Levels of Axl, IFGBP4 and sTNFR2 inversely correlated with plasma complement C3 levels. Only plasma Axl and ferritin levels correlated with degree of proteinuria. These markers were more specific, but less sensitive, in detecting concurrent SLE activity than elevated anti-dsDNA antibody titer or decreased C3. Ferritin and IGFBP4 levels were more specific for concurrent active lupus nephritis than anti-dsDNA or C3. Plasma ferritin was the best monitor of global SLE activity, followed by C3 then Axl, while both Axl and C3 were best monitors of clinical lupus nephritis activity.

CONCLUSION

In childhood-onset SLE patients, plasma ferritin and Axl perform better than traditional yardsticks in identifying disease activity, either global or renal. The performance of these plasma markers should be explored further in longitudinal cohorts of SLE patients.

Utility of serum ferritin and soluble interleukin-2 receptor as markers of disease activity in childhood systemic lupus erythematosus

Objective

To assess the usefulness of serum ferritin and soluble interleukin-2 receptor (sIL-2r) levels as markers of disease activity in childhood systemic lupus erythematosus (cSLE) and their role in screen for subclinical macrophage activation syndrome (MAS).

Patients and methods

This is a cross-sectional analysis of prospectively collected data. Consecutive children who met the Systemic Lupus International Collaborating Clinics (SLICC) criteria were enrolled between June 2015 and June 2017. All patients interviewed and assessed for disease activity using SLE disease activity index (SLEDAI). Biochemical and serological tests including markers of disease activity and MAS were measured by standard laboratory procedure.

Results

A total of 31 (25 female; 6 male) consecutive cSLE patients with a mean age of 10.6 (±3.2) years were included. The most frequent manifestations were mucocutaneous and musculoskeletal (84%) followed by hematological (64.5%) then renal involvement (58%). Twenty-two patients had active disease (SLEDAI ≥ 4), with a mean of 9.8. Mean serum ferritin and sIL-2r were 555 (±1860) and 2789 (±1299) respectively. Both correlated significantly with leucocyte, platelet count, transferrin, C3 and SLEDAI (p < 0.05). Additionally, sIL-2r had positive correlation with ANA, ds-DNA and C4. Both ferritin and sIL-2r had weak correlation with ESR, but no correlation with CRP. Twelve patients had a recent infection. However, they were comparable to patients without infection with regard to all clinical and laboratory features. Three patients had MAS proved by bone marrow aspiration.

Conclusion

Measurement of serum ferritin and sIL-2r might help in assessing disease activity of cSLE. Both might be good screening markers for MAS in cSLE. A larger prospective study is required to allow more definitive conclusions.

Heme Catabolic Pathway in Inflammation and Immune Disorders

In recent years, the heme catabolic pathway is considered to play an important regulatory role in cell protection, apoptosis, inflammation, and other physiological and pathological processes. An appropriate amount of heme forms the basic elements of various life activities, while when released in large quantities, it can induce toxicity by mediating oxidative stress and inflammation. Heme oxygenase (HO) -1 can catabolize free heme into carbon monoxide (CO), ferrous iron, and biliverdin (BV)/bilirubin (BR). The diverse functions of these metabolites in immune systems are fascinating. Decades work shows that administration of degradation products of heme such as CO and BV/BR exerts protective activities in systemic lupus erythematosus (SLE), rheumatoid arthritis (RA), multiple sclerosis (MS) and other immune disorders. This review elaborates the molecular and biochemical characterization of heme catabolic pathway, discusses the signal transduction and immunomodulatory mechanism in inflammation and summarizes the promising therapeutic strategies based on this pathway in inflammatory and immune disorders.

The Role of Inflammation in the Development of GDM and the Use of Markers of Inflammation in GDM Screening

Gestational diabetes mellitus is a hyperglycaemic state first recognised in pregnancy. GDM affects both mother and child. Women with GDM and their new-borns are at risk of developing type 2 diabetes in the future. The screening and diagnostic criteria for GDM are inconsistent and thus novel biomarkers of GDM are required to strengthen the screening and diagnostic processes in GDM. Chronic low-grade inflammation is linked to the majority of the well-established risk factors of GDM such as old age, obesity and PCOS. This review provides an overview of the present knowledge on the pathology of GDM, the screening criteria applied, the role of inflammation in the development of GDM and the use of markers of inflammation namely cytokines, oxidative stress markers, lipids, amino acids and iron markers in screening and diagnosis of GDM.

Macrophage Activation Syndrome (MAS) in a Recently Released Prisoner with Systemic Lupus Erythematosus (SLE)

Patient: Male, 38

Final Diagnosis: Systemic lupus erythematosus • macrophage activation syndrome

Symptoms: Altered mental status • diarrhea • fever • nausea • vomiting • weight loss

Medication: —

Clinical Procedure: —

Specialty: Rheumatology

Hepcidin and Ferritin: Important Mediators in Inflammation Associated Anemia in Systemic Lupus Erythematosus Patients

Systemic Lupus Erythematosus is an autoimmune disease with female preponderance. Anemia is found in 50% of Systemic Lupus Erythematosus patients. This is a cross sectional case control study with 30 female Systemic Lupus Erythematosus patients having inflammation associated anemia (Hemoglobin < 10.0 gm/dl) and 30 age matched controls with the aim to measure serum hepcidin and ferritin levels, correlate and study their role as homeostatic regulators of iron metabolism and utility as markers. Serum transferrin, ferritin, iron, total iron binding capacity, hsCRP, liver enzymes and renal parameters were analyzed by using automated analyser. Hepcidin levels were estimated by Sandwich-ELISA method. There was significant decrease in Iron (p < 0.0001), Iron Binding capacity (p < 0.0001), Transferrin (p < 0.0001) in patients, and a significant increase in inflammatory markers: hs-CRP (p < 0.0001), ESR (p < 0.0001) compared to controls. Significant increase in both Hepcidin (p < 0.0001) and Ferritin (p < 0.0001) was observed in patients with significant positive correlation (r = 0.711) with each other. Additionally, ferritin and hepcidin significantly positively correlated with hs-CRP and ESR (r = 0.526, 0.735); (r = 0.427, 0.742) respectively. Negative correlation with hemoglobin, iron, total iron binding capacity and transferrin with hepcidin (r = - 0.80, - 0.307, - 0.553, - 0.584) and ferritin (r = -0.722, - 0.22, - 0.654, - 0.728) was observed respectively. On ROC analysis both hepcidin and ferritin has sensitivity of 96.7%, specificity of 100% at cut-off values of 110 and 49 respectively. AUC of hepcidin was 0.993 and ferritin was 0.978. We have established a positive linear correlation between Hepcidin and Ferritin levels in disease activity and the changes correlated with the inflammatory state and anemia in patients, making them important mediators and potential markers of inflammation associated anemia.

Binding of anti-dsDNA antibodies to proximal tubular epithelial cells contributes to renal tubulointerstitial inflammation

Immune deposits are often observed along the tubular basement membrane in patients with lupus nephritis, but the role of anti-dsDNA antibody (Ab) deposition on tubulointerstitial inflammation remains to be investigated. We examined the effect of human polyclonal anti-dsDNA Abs on inflammatory processes in cultured proximal renal tubular epithelial cells (PTEC, HK-2 cells) and their association with serum levels of interleukin (IL)-6, IL-8 and monocyte chemoattractant protein-1 (MCP-1) in patients. Binding of anti-dsDNA Abs to HK-2 cells was investigated by cellular ELISA, flow cytometry and immunohistochemistry. IL-6, IL-8 and MCP-1 secretion, mitogen-activated protein kinase (MAPK) activation and the effect of mycophenolic acid (MPA) were investigated by ELISAs and Western blot analysis. NZBWF1/J mice with active nephritis were randomized to receive either mycophenolate mofetil (MMF) (100 mg/kg per day) or vehicle for up to 12 weeks to study renal histopathology focusing on tubulointerstitial changes. Our results demonstrated that anti-dsDNA Abs bound to HK-2 cell surface and induced IL-6, IL-8 and MCP-1 secretion through distinct MAPK pathways. MPA inhibited anti-dsDNA Ab binding to HK-2 cells and suppressed apical and basolateral IL-6 and IL-8, but not MCP-1, secretion. Anti-dsDNA Ab level correlated with serum and tubulointerstitial expression of IL-6, IL-8 and MCP-1. MMF treatment in NZBWF1/J mice reduced anti-dsDNA Ab production and MAPK activation in the renal tubulointerstitium, together with decreased IL-6 and MCP-1 expression. Our data demonstrate that anti-dsDNA Abs contribute to inflammatory processes in the tubulointerstitium in lupus nephritis through their binding to proximal renal tubular epithelial cells and induction of pro-inflammatory mediators, and MPA ameliorates anti-dsDNA Ab induced IL-6 and IL-8 secretion in these cells.

Axl, Ferritin, Insulin-Like Growth Factor Binding Protein 2, and Tumor Necrosis Factor Receptor Type II as Biomarkers in Systemic Lupus Erythematosus

OBJECTIVE

To evaluate the performance of 4 serum protein markers for detecting concurrent clinical activity in patients with systemic lupus erythematosus (SLE).

METHODS

Consecutive patients who fulfilled ≥4 American College of Rheumatology classification criteria for SLE and healthy controls were recruited for serologic testing of 4 protein markers identified by antibody-coated microarray screen, namely Axl, ferritin, insulin-like growth factor binding protein 2 (IGFBP-2), and tumor necrosis factor receptor type II (TNFRII). SLE disease activity was assessed by the Safety of Estrogens in Lupus Erythematosus National Assessment version of the Systemic Lupus Erythematosus Disease Activity Index (SLEDAI) and physician's global assessment (PGA). Levels of these markers were correlated with SLEDAI scores, and their sensitivity and specificity for clinical SLE activity were determined.

RESULTS

A total of 94 SLE patients (98% women, mean ± SD age 28.7 ± 9.4 years, mean ± SD disease duration 5.4 ± 5.0 years) and 49 healthy controls were studied. Fifty-two patients had clinically active SLE (defined as SLEDAI score ≥6 or having a flare). The serum concentrations of Axl, ferritin, IGFBP-2, and TNFRII were significantly higher in patients with active SLE than in those with inactive SLE or in controls. The levels of these markers correlated strongly and significantly with anti-double stranded DNA (anti-dsDNA), C3, and clinical SLEDAI and PGA scores. These markers were more specific, but less sensitive, in detecting concurrent SLE activity than elevated anti-dsDNA or depressed C3. Levels of Axl, TNFRII, and IGFBP-2, but not ferritin, could differentiate active renal from active nonrenal or inactive SLE. The specificity of Axl and IGFBP-2 for concurrent active lupus nephritis was higher than anti-dsDNA or C3.

CONCLUSION

Serum proteomic markers are potentially useful for diagnosing SLE and monitoring disease activity. The performance of Axl and IGFBP-2 in lupus nephritis should be further explored in a longitudinal cohort of SLE patients.

Systemic Lupus Erythematosus Presenting with Massive Ascites: A Case of Pseudo-Pseudo Meigs Syndrome

The case presented is consistent with the phenomenon known as Pseudo-Pseudo Meigs Syndrome (PPMS). In it, we describe a young woman with newly diagnosed Systemic Lupus Erythematosus presenting with ascites, pleural effusions, and an elevated CA-125 level. Although rare, and of uncertain etiology, PPMS is becoming increasingly recognized in the literature. It should be considered as a differential diagnosis in such patients, along with the search for malignancy.

The utility of iron chelators in the management of inflammatory disorders

Since iron can contribute to detrimental radical generating processes through the Fenton and Haber-Weiss reactions, it seems to be a reasonable approach to modulate iron-related pathways in inflammation. In the human organism a counterregulatory reduction in iron availability is observed during inflammatory diseases. Under pathological conditions with reduced or increased baseline iron levels different consequences regarding protection or susceptibility to inflammation have to be considered. Given the role of iron in development of inflammatory diseases, pharmaceutical agents targeting this pathway promise to improve the clinical outcome. The objective of this review is to highlight the mechanisms of iron regulation and iron chelation, and to demonstrate the potential impact of this strategy in the management of several acute and chronic inflammatory diseases, including cancer.

Serum ferritin is an important inflammatory disease marker, as it is mainly a leakage product from damaged cells

"Serum ferritin" presents a paradox, as the iron storage protein ferritin is not synthesised in serum yet is to be found there. Serum ferritin is also a well known inflammatory marker, but it is unclear whether serum ferritin reflects or causes inflammation, or whether it is involved in an inflammatory cycle. We argue here that serum ferritin arises from damaged cells, and is thus a marker of cellular damage. The protein in serum ferritin is considered benign, but it has lost (i.e. dumped) most of its normal complement of iron which when unliganded is highly toxic. The facts that serum ferritin levels can correlate with both disease and with body iron stores are thus expected on simple chemical kinetic grounds. Serum ferritin levels also correlate with other phenotypic readouts such as erythrocyte morphology. Overall, this systems approach serves to explain a number of apparent paradoxes of serum ferritin, including (i) why it correlates with biomarkers of cell damage, (ii) why it correlates with biomarkers of hydroxyl radical formation (and oxidative stress) and (iii) therefore why it correlates with the presence and/or severity of numerous diseases. This leads to suggestions for how one might exploit the corollaries of the recognition that serum ferritin levels mainly represent a consequence of cell stress and damage.

Serum ferritin level correlates with SLEDAI scores and renal involvement in SLE

Introduction

Ferritin is an acute-phase reactant that is elevated in various autoimmune disorders. Serum ferritin levels have been positively correlated with disease activity scores of rheumatoid arthritis and systemic lupus erythematosus (SLE). Further, enhanced levels of ferritin have also been reported in lupus nephritis. However, there are no reports from the Indian subcontinent.

Methods

Seventy-six female SLE patients, diagnosed on the basis of revised ACR criteria, and 50 healthy females, age matched from similar geographical areas, were enrolled in the present study. Serum levels of ferritin, IFN-α and IL-6 were quantified by enzyme-linked immunosorbent assay (ELISA). Clinical, biochemical, serological and other markers of disease activity (C3, C4 and anti-dsDNA) were measured by standard laboratory procedure.

Results

Serum ferritin levels were significantly higher in SLE patients compared to healthy controls ( p < 0.0001). Ferritin levels positively correlated with SLE Disease Activity Index (SLEDAI) ( p = 0.001, r = 0.35), anti-dsDNA ( p = 0.001, r = 0.35), IFN-α ( p < 0.0001, r = 0.51) and IL-6 (p < 0.0001, r = 0.65) and negatively correlated with C3 ( p = 0.0006, r = −0.38) and C4 ( p = 0.01, r = −0.28). Interestingly, serum levels of ferritin were positively associated with proteinuria ( p = 0.001, r = 0.36), serum urea ( p = 0.0004, r = 0.39) and serum creatinine ( p = 0.0006, r = 0.38).

Conclusion

Serum ferritin is an excellent marker of disease activity and renal dysfunction in SLE.

The correlation between ferritin level and acute phase parameters in rheumatoid arthritis and systemic lupus erythematosus

OBJECTIVE

In this study, we evaluated the relationship between ferritin levels and disease activation in rheumatoid arthritis (RA) patients.

MATERIAL AND METHODS

We included 44 patients with RA, 20 patients with systemic lupus erythematosus (SLE), 25 patients with infection, 22 patients with malignancy, and 20 healthy control subjects. Erythrocyte sedimentation rate (ESR), C-reactive protein (CRP), whole blood count, and serum iron parameters were determined in all cases. The joint findings in RA patients were recorded, and disease activity score (DAS) was calculated. In SLE patients, antinuclear antibody (ANA) and anti-dsDNA titers and C3 and C4 complement levels were determined. SLE disease activity index (SLEDAI) score was calculated.

RESULTS

Serum ferritin levels in the RA, SLE, and control groups were lower than those in the infection and malignancy groups (p<0.05). The ferritin levels in the RA group did not differ significantly from the SLE and control groups. In RA patients, serum ferritin level had a positive correlation with ESR, CRP, RF, platelet count, and DAS score and had a negative correlation with hematocrit (all p values <0.05). In SLE patients, on the other hand, serum ferritin had a positive correlation with ANA, anti-dsDNA, and SLEDAI (all p values <0.05). According to DAS, ferritin level in inactive RA patients was lower than that in active RA patients. When transferrin saturation was considered, iron deficiency anemia was a quite frequent finding in both active and inactive RA patients.

CONCLUSION

Interestingly, we observed that ferritin level in RA patients was similar to the control group; however, it was a good parameter of disease activation. This is because a reduction in storage iron and resultant iron deficiency anemia are very common in RA patients.

Characterization and recombinant protein expression of ferritin light chain homologue in the silkworm, Bombyx mori

The silkworm genome encodes three iron storage proteins or ferritins, Fer1HCH, Fer2LCH, and Fer3HCH. Probing our EST library constructed from 1-day-old silkworm eggs revealed only Fer2LCH mRNA, which encoded for a protein with a predicted putative N-glycosylation site. Developmental and tissue expression analyses during embryogenesis revealed that Fer2LCH mRNA was abundant from 6 h to 6 days after oviposition. Transcriptional expression of Fer2LCH during the postembryonic stage is also high in the larval fat body and mid-gut, and then is upregulated in all pupal tissues tested. We found that Fer2LCH mRNA contains an iron-responsive element, suggesting this ferritin subunit is subject to translational control. Although ferritin expression has been shown to increase following immune challenge in other insects, the levels of Fer2LCH mRNA were not significantly induced following viral or bacterial infection of Bombyx mori. Using a baculovirus expression system we expressed recombinant BmFer2LCH protein, which was detectable in the cytoplasmic fraction, likely in a compartment of the secretory pathway, and was shown to undergo posttranslational modifications including N-glycosylation. In particular, rBmFer2LCH carbohydrate chains were composed of mannose and GlcNAc. We suggest that Fer2LCH is important for iron homeostasis and maintaining normal organ function in silkworms.

Ferritin in the antiphospholipid syndrome and its catastrophic variant (cAPS)

BACKGROUND

Ferritin is an iron storage protein considered also as an acute phase reactant with high levels in various inflammatory conditions. Recently, a plausible role for ferritin in the pathogenesis of immune-mediated and especially autoimmune diseases has been suggested. However, the link between ferritin and the antiphospholipid syndrome (APS) has been rarely explored. Therefore, in the current study we evaluated ferritin levels and their correlation to clinical and serological manifestations in patients with APS. We further analyzed ferritin levels among patients with the catastrophic variant of APS (cAPS).

METHODS

Ferritin levels were determined in serum samples of 176 APS patients and 98 matched healthy controls according to age and sex (LIAISON, DiaSorin, Italy). APS samples were further analyzed for antiphospholipid (anti-cardiolipin, anti- beta-2-glycoprotein, lupus anticoagulant) and anti-infectious antibodies (CMV, EBV, rubella, toxoplasma, HBV) (LIAISON, DiaSorin, Italy). Clinical, serological and demographic manifestations were recorded. An additional analysis of ferritin levels among 14 patients with cAPS was performed.

RESULTS

Hyperferritinemia was present in 9% vs. 0% of APS patients and controls, respectively (p < 0.001). Among patients with APS, ferritin levels correlated with venous thrombosis, cardiac, neurological, and hematological manifestations and the presence of anti-CMV-IgM antibodies. Hyperferritinemia was present in 71% of cAPS patients, and ferritin levels among this subgroup were significantly higher compared with APS-non-cAPS patients (816 ± 847 ng/ml vs. 120 ± 230 ng/ml, p < 0.001).

CONCLUSIONS

Herein, we found that hyperferritinemia correlates with the presence of APS, its clinical manifestations and specifically with the catastrophic variant of this disease. Hyperferritinemia was also linked with anti-CMV antibodies among patients with APS. These associations allude to a pathogenic role of ferritin in the pathogenesis of APS, and the plausible role of ferritin as a marker of ensuing cAPS, although further studies are needed to elucidate these associations.

Relationship between iron metabolism, oxidative stress, and insulin resistance in patients with systemic lupus erythematosus

OBJECTIVE

The aim of the present study was to assess oxidative stress and iron metabolism in systemic lupus erythematosus (SLE) patients with and without insulin resistance (IR).

METHOD

This study included 236 subjects (125 controls and 111 SLE patients). Patients with SLE were divided in two groups: with (n = 72) or without (n = 39) IR.

RESULTS

SLE patients with IR showed higher advanced oxidation protein product (AOPP) levels (p = 0.030) and gamma-glutamyltransferase (GGT) levels (p = 0.001) and lower sulfhydryl groups of proteins (p = 0.0002) and total radical-trapping antioxidant parameter (TRAP) corrected by uric acid (UA) levels (p = 0.04) when compared to SLE patients without IR. However, SLE patients with IR presented lower serum 8-isoprostane (p = 0.05) and carbonyl protein levels (p = 0.04) when compared to SLE patients without IR. Serum ferritin levels were significantly higher in SLE patients (p = 0.0006) than in controls, and SLE patients with IR presented higher serum ferritin levels (p = 0.01) than SLE patients without IR. Patients with SLE showed that IR was inversely correlated to TRAP/UA (r = -0.2724, p = 0.0008) and serum ferritin was positively correlated to AOPP (r = 0.2870, p = 0.004).

CONCLUSIONS

This study found that oxidative stress was higher in the group of SLE patients with IR, and increased ferritin, whether caused by the inflammatory process per se or hyperinsulinaemia, can favour the redox process. In addition, the preset data reinforce the need to measure oxidative stress with several methodologies with different assumptions.

Inflammation associated anemia and ferritin as disease markers in SLE

Introduction

In a recent screening to detect biomarkers in systemic lupus erythematosus (SLE), expression of the iron storage protein, ferritin, was increased. Given that proteins that regulate the storage, transfer and release of iron play an important role in inflammation, this study aims to determine the serum and urine levels of ferritin and of the iron transfer protein, transferrin, in lupus patients and to correlate these levels with disease activity, inflammatory cytokine levels and markers of anemia.

Methods

A protein array was utilized to measure ferritin expression in the urine and serum of SLE patients and healthy controls. To confirm these results as well as the role of the iron transfer pathway in SLE, ELISAs were performed to measure ferritin and transferrin levels in inactive or active SLE patients and healthy controls. The relationship between ferritin/transferrin levels and inflammatory markers and anemia was next analyzed.

Results

Protein array results showed elevated ferritin levels in the serum and urine of lupus patients as compared to controls, which were further validated by ELISA. Increased ferritin levels correlated with measures of disease activity and anemia as well as inflammatory cytokine titers. Though active SLE patients had elevated urine transferrin, serum transferrin was reduced.

Conclusion

Urine ferritin and transferrin levels are elevated significantly in SLE patients and correlate with disease activity, bolstering previous reports. Most importantly, these changes correlated with the inflammatory state of the patients and anemia of chronic disease. Taken together, altered iron handling, inflammation and anemia of chronic disease constitute an ominous triad in SLE.

Laboratory testing in pediatric rheumatology

In children, laboratory evaluations can assist in the screening of patients for inflammatory disorders, confirm diagnoses, allow for monitoring of disease activity and response to therapy, and suggest prognoses and risk of morbidities associated with rheumatic diseases. This review provides an overview of the usefulness and interpretation of both the commonly ordered tests ordered by the general pediatrician as well as those frequently used in the pediatric rheumatology clinic for diagnosis and disease monitoring. Studies discussed include the complete blood count, acute phase reactants, autoantibodies, serum complement, urinalysis, streptococcal antibody tests, and commonly used genetic studies.

Iron Deficiency Anemia in Adult Onset Still's Disease with a Serum Ferritin of 26,387 μg/L

Serum ferritin rises in the anemia of chronic inflammation reflecting increased iron storage and other changes mediated by inflammation. When iron deficiency coexists, the ferritin may not always decline into the subnormal range. We describe the rare interaction of iron deficiency with the extreme hyperferritinemia characteristic of adult onset Still's disease. The combination has clinical relevance and allows deductions about the presence of serum ferritin at 26,387 μg/L despite obvious iron depletion. The diagnosis of iron deficiency anemia was delayed and became fully obvious when her Still's disease remitted and serum ferritin decreased to 6.5 μg/L. The coexistence of iron deficiency should be considered when evaluating a patient with anemia of chronic inflammation even when the ferritin level is elevated several hundredfold. Further insights on ferritin metabolism in Still's disease are suggested by the likelihood that the patient's massive hyperferritinemia in the acute phase of Still's disease was almost entirely of the iron-free apoferritin form.

Towards a unifying, systems biology understanding of large-scale cellular death and destruction caused by poorly liganded iron: Parkinson's, Huntington's, Alzheimer's, prions, bactericides, chemical toxicology and others as examples

Exposure to a variety of toxins and/or infectious agents leads to disease, degeneration and death, often characterised by circumstances in which cells or tissues do not merely die and cease to function but may be more or less entirely obliterated. It is then legitimate to ask the question as to whether, despite the many kinds of agent involved, there may be at least some unifying mechanisms of such cell death and destruction. I summarise the evidence that in a great many cases, one underlying mechanism, providing major stresses of this type, entails continuing and autocatalytic production (based on positive feedback mechanisms) of hydroxyl radicals via Fenton chemistry involving poorly liganded iron, leading to cell death via apoptosis (probably including via pathways induced by changes in the NF-κB system). While every pathway is in some sense connected to every other one, I highlight the literature evidence suggesting that the degenerative effects of many diseases and toxicological insults converge on iron dysregulation. This highlights specifically the role of iron metabolism, and the detailed speciation of iron, in chemical and other toxicology, and has significant implications for the use of iron chelating substances (probably in partnership with appropriate anti-oxidants) as nutritional or therapeutic agents in inhibiting both the progression of these mainly degenerative diseases and the sequelae of both chronic and acute toxin exposure. The complexity of biochemical networks, especially those involving autocatalytic behaviour and positive feedbacks, means that multiple interventions (e.g. of iron chelators plus antioxidants) are likely to prove most effective. A variety of systems biology approaches, that I summarise, can predict both the mechanisms involved in these cell death pathways and the optimal sites of action for nutritional or pharmacological interventions.

Autoimmunity in hepatitis C virus carriers: involvement of ferritin and prolactin

BACKGROUND

Ferritin and prolactin have been associated with active autoimmune diseases as systemic lupus erythematosus and autoantibody production, but have been little studied in viral infections that present autoimmunity.

OBJECTIVE

To investigate the association of these two autoimmune mediators with the presence of cryoglobulinaemia and non-organ-specific autoantibodies (RF, SMA, β2GPI IgA antibody and ANA) in Brazilian individuals chronically infected with hepatitis C virus (HCV).

METHODS

Ninety-nine patients were evaluated. Ferritin and prolactin levels were determined by chemiluminescent immunoassays.

RESULTS

Hyperprolactinemia was found in 10 (six men and four women) out of 99 (10.1%) hepatitis C patients. Thirty-eight out of 99 (38.4%) HCV carriers had hyperferritinemia (median level 385ng/mL). Neither hyperprolactinemia nor hyperferritinemia was associated with cryoglobulinaemia or non-organ-specific autoantibodies (p>.05). There was an association between hyperprolactinemia and the infection with HCV genotype 3 (p<.01). Ferritin and ALT levels were correlated (p<.05).

CONCLUSION

Our results suggest that neither prolactin nor ferritin is involved with the extra-hepatic manifestation of autoimmunity observed in HCV carriers.

Commentary: Iron deficiency and hair loss: problems with measurement of iron

Iron is involved in many critical physiologic processes within the hair follicle, suggesting that iron deficiency could disrupt hair synthesis. However, studies of iron as a cause of hair loss have produced conflicting results. Some of the discrepancies may relate to limitations of assays for iron deficiency. This commentary discusses the sensitivity and specificity of available tests for iron deficiency and presents practical guidelines for testing and supplementation.

Clinical manifestation and prognostic factor in anti-melanoma differentiation-associated gene 5 antibody-associated interstitial lung disease as a complication of dermatomyositis

OBJECTIVE

The aim of this study is to evaluate the clinical manifestation and prognostic factors of anti-melanoma differentiation-associated gene 5 (MDA5) antibody-associated interstitial lung disease (ILD) with DM.

METHODS

Fourteen patients who presented with anti-MDA5 antibody and 10 patients with anti-aminoacyl-tRNA synthetase (ARS) antibody were enrolled. All patients were diagnosed as having DM with ILD. Clinical manifestations in the patients with anti-MDA5 antibody were compared with those in the patients with anti-ARS antibody.

RESULTS

The frequencies of acute/subacute interstitial pneumonia (A/SIP) and fatal outcome were significantly higher in the subset with anti-MDA5 antibody. The creatine kinase (CK) value was significantly lower and the gamma-glutamyl transpeptidase and ferritin values were significantly higher in the subset with anti-MDA5 antibody. Significant correlations were found between PaO(2)/F(i)O(2) and ferritin (r(s) = -0.59, P = 0.035), alveolar-arterial oxygen difference (A-aDO(2)) and KL-6 (r(s) = 0.73, P = 0.016) and A-aDO(2) and ferritin (r(s) = 0.66, P = 0.013) in the subset with anti-MDA5 antibody. The most significant prognostic factor was ferritin. The cumulative survival rate was significantly lower (P < 0.0001) in the subset with ferritin >or=1600 ng/ml than that in the subset with ferritin <1600 ng/ml in anti-MDA5 antibody-associated ILD.

CONCLUSION

Both serum ferritin and anti-MDA5 antibody are powerful indicators for the early diagnosis of A/SIP with DM. Ferritin also predicts disease severity and prognosis for patients with anti-MDA5 antibody. Intensive treatment should be administered to cases that have anti-MDA5 antibody-associated ILD with DM showing hyperferritinaemia, especially if the ferritin level is >or=1600 ng/ml.

Increased ferritin predicts development and severity of acute interstitial lung disease as a complication of dermatomyositis

OBJECTIVES

Acute/subacute interstitial pneumonia (A/SIP) is an intractable and fatal complication of DM. Since a useful indicator predicting the complication of A/SIP has not been found, the aim of this study was to determine whether serum ferritin is a potential predictive indicator of the occurrence of A/SIP in 64 patients with DM.

METHODS

Of the total patients enrolled, 19 had A/SIP, 24 had chronic interstitial pneumonia and 21 were without interstitial lung disease (ILD). Clinical manifestations and laboratory data were obtained from medical records on admission.

RESULTS

Serum ferritin levels were extremely high in patients with DM with A/SIP. It was significantly higher in DM with A/SIP than that in DM without A/SIP (median 790 vs 186 ng/ml; P < 0.0001). The cumulative survival rate for 6 months was 62.7% in patients with DM with A/SIP. Moreover, the cumulative survival rate was significantly (P = 0.016) lower in the group with ferritin levels > or =1500 ng/ml than the rate in the group with ferritin levels <1500 ng/ml.

CONCLUSIONS

Serum ferritin can be useful as a predictor of the occurrence of A/SIP and correlates with the prognosis of A/SIP in DM. The intensive treatment using combination therapy with various immunosuppressant agents should be chosen for patients with ILD with DM showing hyperferritinaemia, especially levels >1500 ng/ml.

Diffuse chronic leptomeningitis with seropositive rheumatoid arthritis: report of a case successfully treated as rheumatoid leptomeningitis

A case of biopsy-confirmed chronic leptomeningitis complicating rheumatoid arthritis in a 53-year old female is reported. Her symptoms included weight loss, severe depression, and pyrexia. Magnetic resonance imaging was useful in diagnosis. Intravenous methylprednisolone was prescribed (1 g/day for 3 days), followed by prednisolone (initial dose of 30 mg daily), and this treatment was effective. Her IgG-index, serum levels of soluble interleukin-2 receptor and ferritin, and cerebrospinal level of interleukin-6 paralleled her clinical course.

Iron behaving badly: inappropriate iron chelation as a major contributor to the aetiology of vascular and other progressive inflammatory and degenerative diseases

BACKGROUND

The production of peroxide and superoxide is an inevitable consequence of aerobic metabolism, and while these particular 'reactive oxygen species' (ROSs) can exhibit a number of biological effects, they are not of themselves excessively reactive and thus they are not especially damaging at physiological concentrations. However, their reactions with poorly liganded iron species can lead to the catalytic production of the very reactive and dangerous hydroxyl radical, which is exceptionally damaging, and a major cause of chronic inflammation.

REVIEW

We review the considerable and wide-ranging evidence for the involvement of this combination of (su)peroxide and poorly liganded iron in a large number of physiological and indeed pathological processes and inflammatory disorders, especially those involving the progressive degradation of cellular and organismal performance. These diseases share a great many similarities and thus might be considered to have a common cause (i.e. iron-catalysed free radical and especially hydroxyl radical generation).The studies reviewed include those focused on a series of cardiovascular, metabolic and neurological diseases, where iron can be found at the sites of plaques and lesions, as well as studies showing the significance of iron to aging and longevity. The effective chelation of iron by natural or synthetic ligands is thus of major physiological (and potentially therapeutic) importance. As systems properties, we need to recognise that physiological observables have multiple molecular causes, and studying them in isolation leads to inconsistent patterns of apparent causality when it is the simultaneous combination of multiple factors that is responsible.This explains, for instance, the decidedly mixed effects of antioxidants that have been observed, since in some circumstances (especially the presence of poorly liganded iron) molecules that are nominally antioxidants can actually act as pro-oxidants. The reduction of redox stress thus requires suitable levels of both antioxidants and effective iron chelators. Some polyphenolic antioxidants may serve both roles.Understanding the exact speciation and liganding of iron in all its states is thus crucial to separating its various pro- and anti-inflammatory activities. Redox stress, innate immunity and pro- (and some anti-)inflammatory cytokines are linked in particular via signalling pathways involving NF-kappaB and p38, with the oxidative roles of iron here seemingly involved upstream of the IkappaB kinase (IKK) reaction. In a number of cases it is possible to identify mechanisms by which ROSs and poorly liganded iron act synergistically and autocatalytically, leading to 'runaway' reactions that are hard to control unless one tackles multiple sites of action simultaneously. Some molecules such as statins and erythropoietin, not traditionally associated with anti-inflammatory activity, do indeed have 'pleiotropic' anti-inflammatory effects that may be of benefit here.

CONCLUSION

Overall we argue, by synthesising a widely dispersed literature, that the role of poorly liganded iron has been rather underappreciated in the past, and that in combination with peroxide and superoxide its activity underpins the behaviour of a great many physiological processes that degrade over time. Understanding these requires an integrative, systems-level approach that may lead to novel therapeutic targets.

Ferritin in autoimmune diseases

Iron, an essential element for many important cellular functions in all living organisms, can catalyze the formation of potentially toxic free radicals. Excessive iron is sequestered by ferritin in a nontoxic and readily available form in a cell. Ferritin is composed of 24 subunits of different proportions of two functionally distinct subunits: ferritin H and L. The expression of ferritin is under delicate control and is regulated at both the transcriptional and post-transcriptional levels by iron, cytokines, hormones, and oxidative stress. Mutations in the ferritin gene cause the hereditary hyperferritinemia-cataract syndrome and neuroferritinopathy. Hyperferritinemia is associated with inflammation, infections, and malignancies. While elevated levels of ferritin are characteristic of adult-onset Still's disease and hemophagocytic syndrome, both associated with inflammation, it has scantly been evaluated in other autoimmune diseases. In this review, we describe ferritin structure and function, hyperferritinemia in disease states and in autoimmune diseases.

Association of elevated serum ferritin levels and the risk of gestational diabetes mellitus in pregnant women: The Camden study

OBJECTIVE- We examined the influence of a moderately elevated serum ferritin level at entry to care on the risk of gestational diabetes mellitus (GDM) and a possible mechanism (increased iron stores versus inflammation). RESEARCH DESIGN AND METHODS- In a prospective observational study with 1,456 healthy pregnant women in Camden, New Jersey, serum ferritin and anthropometric measurements were determined. Serum C-reactive protein (CRP) concentration was measured in a nested case-control study of 172 subjects. RESULTS- Women who developed GDM had a higher concentration of serum ferritin than women who did not develop GDM (P < 0.001). Elevated serum ferritin level (highest quintile) was significantly and positively correlated with prepregnant BMI and skinfold measurements. Women in the highest quintile of serum ferritin had a twofold increased risk of developing GDM adjusted for several known risk factors (adjusted odds ratio, 2.02 [95% CI 1.04-3.92], P < 0.05). Similar results were obtained with a nested case-control study, in which women in the highest tertile of serum ferritin (2.35 [1.06-5.22], P < 0.05) or CRP (2.67 [1.16-6.17], P < 0.001) had a greater than twofold increased risk of GDM. However, these effects were modified and became nonstatistically significant after additional adjustment for prepregnant BMI. CONCLUSIONS- Elevated serum ferritin concentrations early in gestation are associated with an increased risk of GDM. The association, at least in part, is mediated by the maternal fat mass and obesity. These data suggest a possible link between elevated serum ferritin and low-grade inflammation.

Latex agglutination test for ferritin measurement

Ferritin is an indispensable parameter in the diagnosis of latent iron deficiency anemia or siderosis. In this study, we evaluated the utility of a reagent for ferritin measurement in a latex agglutination (LA) test, using general chemistry analyzers. The intraassay coefficient of variation (CV) was 0.8-3.4% and the interassay CV was 0.0-0.7%. Linearity was observed up to 1100 ng/mL. The effective sensitivity value was 4.0 ng/mL. In addition, good results were obtained with the prozone test, the effects of interferences, correlation with the enzyme immunoassay (EIA) method, and functional assay sensitivity. A significant positive correlation with C-reactive protein (r=0.586, P<0.001) was found. When compared with liver-related biochemical parameters (asparate aminotransferase (AST) and alanine aminotransferase (ALT)) in patients with impaired liver function, ferritin varied in parallel with the liver-related parameters. This assay system was able to measure ferritin accurately over a wide range, and thus could be used to diagnose cancer, siderosis, and iron deficiency anemia. The LA assay system can be employed for measurement with general chemistry analyzers, with rapid and convenient execution. In addition, the LA test allows the simultaneous measurement of other markers of iron deficiency anemia, so clinicians can rapidly obtain examination results.

Effects of daily consumption of honey solution on hematological indices and blood levels of minerals and enzymes in normal individuals

Seven men and three women (mean age, 31.2 years; range, 20-45 years) received a strictly controlled regular diet during a 2-week control period, followed by the regular diet supplemented with daily consumption of 1.2 g/kg body weight honey dissolved in 250 ml of water during a 2-week test period. At the end of each period, overnight fasting blood samples were withdrawn for assays of blood glucose, blood minerals, vitamin C, beta-carotene, uric acid, glutathione reductase, immunoglobulin E, hemoglobin, blood indices and cells, serum ferritin, serum iron, and iron-binding capacity. Results showed that honey increased antioxidant agents. It increased blood vitamin C concentration by 47%, beta-carotene by 3%, uric acid by 12%, and glutathione reductase by 7%. Honey increased serum iron by 20% and decreased plasma ferritin by 11%. It increased the percentage of monocytes by 50%, and increased lymphocyte and eosinophil percentages slightly. Honey reduced serum immunoglobulin E by 34% and increased serum copper by 33%. It decreased aspartate transaminase by 22% and alanine transaminase by 18%. Honey markedly reduced lactic acid dehydrogenase by 41%, decreased creatinine kinase by 33%, and reduced fasting blood sugar by 5%. It caused slight elevations in blood zinc and magnesium, hemoglobin, and packed cell volume. It may be concluded that honey increased antioxidant agents, serum iron and blood indices, and trace elements and decreased immunoglobulin E, liver and muscle enzymes, and fasting blood sugar in healthy subjects.

Regulated secretion of glycosylated human ferritin from hepatocytes

Serum ferritin has been used widely in clinical medicine chiefly as an indicator of iron stores and inflammation. Circulating ferritin also can have paracrine effects. Despite the clinical significance of serum ferritin, its secretion remains an enigma. The consensus view is that serum ferritin arises from tissue ferritins--principally ferritin light--which can be glycosylated. Ferritin heavy and light chains are cytosolic proteins that form cages of 24 subunits to store intracellular iron. We show that ferritin light is secreted when its expression is increased in stable, transfected HepG2 cells or adenovirus-infected HepG2 cells. Export occurs through the classical secretory pathway and some chains are N-glycosylated. Ferritins do not need to form cages prior to secretion. Secretion is blocked specifically, effectively, and rapidly by a factor in serum. The timing of this inhibition of ferritin secretion suggests that normally cytosolic ferritin L is targeted to the secretory pathway during translation despite the absence of a conventional signal sequence. Thus, secretion of glycosylated and unglycosylated ferritin is a regulated and not a stochastic process.

Profiles of the acute-phase reactants C-reactive protein and ferritin related to the disease course of patients with systemic lupus erythematosus

OBJECTIVE

To obtain insight in the acute-phase response in SLE.

METHODS

The clinical history, SLEDAI, CRP and ferritin concentrations were analysed throughout the disease course of 10 SLE patients.

RESULTS

During a mean follow-up of 4.8 years, 10 exacerbations (SLEDAI > or = 11) occurred. Throughout the disease course, CRP and SLEDAI correlated positively in 5 patients, whereas the correlation between SLEDAI and ferritin was positive in 7 patients. However, elevated CRP concentrations together with elevated ferritin levels were only observed during 4 exacerbations. Ferritin concentrations were exceptionately high (> 1500 microg/L) during 4 flare-ups. CRP and ferritin levels remained normal during 5 exacerbations.

CONCLUSION

SLE is characterised by highly variable and unusual CRP and ferritin responses that do not always reflect the extent of inflammation in individual patients. Despite severe disease activity, ferritin levels can remain well within the normal range, limiting its clinical usefulness as a marker for disease activity.

Infections in the immunocompromised rheumatologic patient

Immunocompromised patients with rheumatic diseases have an increased risk of infections. A major risk factor for infection seems to be the immunosuppressive therapy used. Newer therapies for RA may lead to increased rates of infection by opportunistic pathogens such as Mycobacteria tuberculosis. Because disease manifestation may mimic signs and symptoms of infection, prompt diagnosis may be difficult. Familiarity with the likely infections and their causes should aid in obtaining the appropriate culture specimens.