Serum Levels of Zinc, Albumin, Interleukin-6 and CRP in Patients with Unipolar and Bipolar Depression: Cross Sectional Study.

Unipolar (UD) and bipolar depression (BDD) show a high degree of similarity in clinical presentations, which complicates the differential diagnosis of these disorders. The aim of this study was to investigate the serum levels of interleukin 6 (IL-6), C-reactive protein (CRP), albumin (Alb), and zinc (Zn) in patients with UD, BDD, and healthy controls (HC). A total of 211 samples were collected: 131 patient samples (65 UD and 68 BDD) and 80 HC. The Montgomery-Asberg Depression Rating Scale (MADRS), along with the Hamilton Depression Rating Scale (HAMD-17), were administered to patient groups to evaluate symptoms. A cross-sectional study was performed to analyse the serum levels of IL-6, CRP, albumin, and zinc. The concentration of CRP was determined using the immunoturbidimetry method, zinc using the colorimetric method, and albumin using the colorimetric method with bromocresol green on the Alinity c device. IL-6 cytokine concentration in serum samples was ascertained using a commercial enzyme immunoassay, ELISA. We found no significant differences in serum concentrations of zinc, albumin, CRP, and IL-6 between the groups of patients with unipolar and bipolar depression. There was a significant statistical difference (p < 0.001) between serum levels of all investigated parameters in both groups of depressed patients in comparison with HC. Furthermore, correlations with specific items on HAMD-17; (namely, hypochondrias, work and activities, somatic symptoms-general, and weight loss) and on MADRS (concentration difficulties, lassitude) were observed in both patient groups. These findings confirm the presence of low-grade inflammation in depression, thus adding better insight into the inflammation hypothesis directed to explain the aetiology of depressive disorders. Our results do not indicate potential biomarkers for distinguishing between unipolar and bipolar depression.

Insight into the Interplay of Gd-IgA1, HMGB1, RAGE and PCDH1 in IgA Vasculitis (IgAV).

The pathogenesis of IgAV, the most common systemic vasculitis in childhood, appears to be complex and requires further elucidation. We aimed to investigate the potential role of galactose-deficient immunoglobulin A1 (Gd-IgA1), high-mobility group box 1 (HMGB1), receptor for advanced glycation end products (RAGE) and protocadherin 1 (PCDH1) in the pathogenesis of IgAV. Our prospective study enrolled 86 patients with IgAV and 70 controls. HMGB1, RAGE, Gd-IgA1 and PCDH1 in serum and urine were determined by the enzyme-linked immunosorbent assay (ELISA) method at the onset of the disease and after a six-month interval in patients and once in the control group. Serum concentrations of HMGB1, RAGE and PCDH1 and urinary concentrations of HMGB1, RAGE, Gd-IgA1 and PCDH1 were significantly higher in patients with IgAV than in the control group (p < 0.001). Concentrations of HMGB1 (5573 pg/mL vs. 3477 pg/mL vs. 1088 pg/mL, p < 0.001) and RAGE (309 pg/mL vs. 302.4 pg/mL vs. 201.3 pg/mL, p = 0.012) in the serum of patients remained significantly elevated when the disease onset was compared with the six-month follow-up interval, and thus could be a potential marker of disease activity. Urinary concentration of HMGB1 measured in the follow-up period was higher in patients with nephritis compared to IgAV without nephritis (270.9 (146.7-542.7) ng/mmol vs. 133.2 (85.9-318.6) ng/mmol, p = 0.049) and significantly positively correlated with the urine albumine to creatinine ratio (τ = 0.184, p < 0.05), the number of erythrocytes in urine samples (τ = 0.193, p < 0.05) and with the outcome of nephritis (τ = 0.287, p < 0.05); therefore, HMGB1 could be a potential tool for monitoring patients with IgAV who develop nephritis. Taken together, our results imply a possible interplay of Gd-IgA1, HMGB1, RAGE and PCDH1 in the development of IgAV. The identification of sensitive biomarkers in IgAV may provide disease prevention and future therapeutics.

Analytical aspects of the antinuclear antibody test by HEp-2 indirect immunofluorescence: EFLM report on an international survey.

OBJECTIVES: Detection of antinuclear antibodies (ANA) by indirect immunofluorescence assay using HEp-2 cells (HEp-2 IFA) is used to screen for various autoimmune diseases. HEp-2 IFA suffers from variability, which hampers harmonization. METHODS: A questionnaire was developed to collect information on HEp-2 IFA methodology, computer-assisted diagnosis (CAD) systems, training, inter-observer variability, quality assessment, reagent lot change control, and method verification. The questionnaire was distributed to laboratories by Sciensano (Belgium), national EASI groups (Italy, Croatia, Portugal, Estonia, Greece) and ICAP (worldwide). Answers were obtained by 414 laboratories. The results were analysed in the framework of the recent EFLM/EASI/ICAP ANA recommendations (companion paper). RESULTS: Laboratories used either HEp-2, HEp-2000, or HEp-20-10 cells and most laboratories (80%) applied the same screening dilution for children and adults. The conjugate used varied between laboratories [IgG-specific (in 57% of laboratories) vs. polyvalent]. Sixty-nine percent of CAD users reviewed the automatic nuclear pattern and 53% of CAD users did not fully exploit the fluorescence intensity for quality assurance. Internal quality control was performed by 96% of the laboratories, in 52% of the laboratories only with strongly positive samples. Interobserver variation was controlled by 79% of the laboratories. Limited lot-to-lot evaluation was performed by 68% of the laboratories. Method verification was done by 80% of the respondents. CONCLUSIONS: Even though many laboratories embrace high-quality HEp-2 IFA, substantial differences in how HEp-2 IFA is performed and controlled remain. Acting according to the EFLM/EASI/ICAP ANA recommendations can improve the global performance and quality of HEp-2 IFA and nurture harmonization.

Detection of antinuclear antibodies: recommendations from EFLM, EASI and ICAP.

OBJECTIVES: Antinuclear antibodies (ANA) are important for the diagnosis of various autoimmune diseases. ANA are usually detected by indirect immunofluorescence assay (IFA) using HEp-2 cells (HEp-2 IFA). There are many variables influencing HEp-2 IFA results, such as subjective visual reading, serum screening dilution, substrate manufacturing, microscope components and conjugate. Newer developments on ANA testing that offer novel features adopted by some clinical laboratories include automated computer-assisted diagnosis (CAD) systems and solid phase assays (SPA). METHODS: A group of experts reviewed current literature and established recommendations on methodological aspects of ANA testing. This process was supported by a two round Delphi exercise. International expert groups that participated in this initiative included (i) the European Federation of Clinical Chemistry and Laboratory Medicine (EFLM) Working Group "Autoimmunity Testing"; (ii) the European Autoimmune Standardization Initiative (EASI); and (iii) the International Consensus on ANA Patterns (ICAP). RESULTS: In total, 35 recommendations/statements related to (i) ANA testing and reporting by HEp-2 IFA; (ii) HEp-2 IFA methodological aspects including substrate/conjugate selection and the application of CAD systems; (iii) quality assurance; (iv) HEp-2 IFA validation/verification approaches and (v) SPA were formulated. Globally, 95% of all submitted scores in the final Delphi round were above 6 (moderately agree, agree or strongly agree) and 85% above 7 (agree and strongly agree), indicating strong international support for the proposed recommendations. CONCLUSIONS: These recommendations are an important step to achieve high quality ANA testing.

2019 ACR/EULAR classification criteria and therapy in predicting organ damage accrual in patients with childhood-onset systemic lupus erythematosus: A retrospective study over the last 29 years.

OBJECTIVE: We explored damage occurrence in patients with childhood-onset SLE (cSLE) and aimed to predict the risk of organ damage occurrence in time. METHODS: The retrospective study included patients treated for cSLE at the Centre of Reference for Pediatric and Adolescent Rheumatology of the Republic Croatia over a 29-year period. RESULTS: The disease development of 97 patients (77 females) with cSLE was examined. The median (Q1, Q3) follow-up time was 6.5 (2.3, 12.0) years. SDI was determined at 5 time points (6, 12, 24, 36 months, and last follow-up). Thirty-eight patients (48%) had organ damage at the last follow-up. Prepubertal group of patients showed higher SLEDAI scores at the disease onset, while post-pubertal group had significantly lower proportion of patients with relapses. We estimated the time from the first symptom to the moment of damage and our findings suggest that it is unlikely that organ damage will occur in 50% of patients in the first 6 years since the diagnosis. The number of 2019 ACR/EULAR classification criteria at the time of diagnosis associated with SDI determined after 1 year of the follow-up period. The patients who received higher doses of glucocorticoids accumulated damage faster and mycophenolate mofetil was found to be a more frequent therapy in patients with SDI ≥3. CONCLUSION: Knowing that damage will most likely happen after the first 6 years after diagnosis in 50% of patients enables physicians to better predict damage occurrence. High number of 2019 ACR/EULAR criteria and treatment with glucocorticoids in childhood-onset SLE are associated with damage accrual and these findings could enable us to detect patients which should be closely monitored for higher risk of damage development.

Persistence and Severity of Cutaneous Manifestations in IgA Vasculitis Is Associated with Development of IgA Vasculitis Nephritis in Children.

BACKGROUND/OBJECTIVE: The purpose of this study was to evaluate the prevalence and severity of skin involvement in children with IgA vasculitis (IgAV) and its relationship with clinical and biochemical parameters and the risk of developing IgA vasculitis nephritis (IgAVN), the only cause of long-term morbidity and the main prognostic factor in IgAV patients. METHODS: This national multicenter retrospective study included 611 patients under the age of 18 years with IgAV referred to five Croatian tertiary hospitals between 2009 and 2019. Patient data were collected from a database with systematic analysis of IgAV patients in the Croatian population. RESULTS: Among the 611 children, 205 (33.55%) had purpura on the lower extremities, in 207 (33.88%) the rash extended on the trunk, in 149 (24.39%) it extended to the upper extremities, in 32 (5.24%) the rash was generalized, while 15 (2.47%) had the most severe skin symptoms: bullae, ulcerations, and necroses. IgAVN developed in 130 (21.28%) and persistent IgAVN (present for >3 months) in 48 (7.86%) children. Multivariate logistic regression found that presence of ulcerations and necroses (OR 3.20 [95% CI 1.03-9.91]), persistent purpura (OR 2.89 [95% CI 1.71-4.88]), and higher age (OR 1.16 [95% CI 1.09-1.23]) were significant predictors of IgAVN, whereas persistent purpura (OR 20.11 [95% CI 1.09-372.52]), male sex (OR 3.32 [95% CI 1.13-9.80]), and higher age (OR 1.15 [95% CI 1.00-1.30]) were predictors of persistent IgAVN. Among the laboratory parameters, higher serum urea (OR 1.43 [95% CI 1.03-2.00]) and reduction in activated partial thromboplastin time (OR 0.83 [95% CI 0.74-0.93]) were shown to have a significant impact on increasing the risk of persistent IgAVN. CONCLUSION: With increasing severity and duration of cutaneous manifestations in IgAV, the risk of developing IgAVN increases, making the prognosis worse, with a greater likelihood to need more aggressive treatment.

Unusual total anti-SARS-CoV-2 antibody kinetics observed during longitudinal monitoring after BNT162b2 vaccination.

The present study aimed to clarify unusual total antibody kinetics in three female individuals observed during longitudinal monitoring of antibody response to BNT162b2 COVID-19 vaccine in 54 healthy volunteers. Total and IgG antibodies against the SARS-CoV-2 spike glycoprotein were measured using Roche and Abbott quantitative assays, respectively, a day before and 8, 71, 135 and 217 days after the second dose. Samples showing unusual kinetics were additionally tested with Beckman Coulter and Euroimmun IgG assays, as well as IgA assay. Antibody levels peaked 8 days after the second dose (total:2769 U/mL; IgG:20022 AU/mL) and declined to 611 U/mL (total) and 783 AU/mL (IgG), after 217 days. A delayed increase of total but not IgG antibodies evidenced in three females, was in two cases coupled with an increase in IgA antibodies. This study identified a previously unknown contribution of anti-SARS-CoV-2 IgA antibodies to a delayed total antibody increase in a subgroup of vaccinated individuals. It also emphasizes that different commercially available serological assays do not provide uniform information about the post-vaccination immune status and that thorough understanding the assays' features is crucial for the proper interpretation of antibody response monitoring.

Analytical validation of 39 clinical chemistry tests and 17 immunoassays on the Alinity analytical system.

The aim of this study was to perform the analytical validation of Alinity c and i analyzers (Abbott Laboratories, Chicago, IL, USA) for 39 clinical chemistry tests and 17 immunoassays. Precision was evaluated at least at two concentration levels for 5 days in quintuplicate, following CLSI EP15-A3. Method comparison included parallel analysis of leftover routine samples on Alinity analyzers and the previously used Cobas c501 and e601 (Roche Diagnostics, Mannheim, Germany). Linearity was tested by preparing sequential sample dilutions with high analyte concentration, following the CLSI EP6 document. For clinical chemistry tests, within-run coefficients of variation (CV) were up to 6.0% (beta-2-microglobulin), while between-run CVs up to 5.4% (immunoglobulin M). Among immunoassays, the highest within-run CV was obtained for vitamin B12 (6.9%), while between-run for CA 19-9 (4.3%). Complete agreement with Roche analyzers was observed for 16 (41%) clinical chemistry assays and 6 (35%) immunoassays. Half of all evaluated assays did not meet the desirable biological variation criteria for bias, being especially exceeded for alpha1-antitrypsin, apolipoprotein A1, ceruloplasmin, complement C3 and C4, hemoglobin A1c, lipoprotein (a) and myoglobin, as well as some tumor markers (CA 125, CEA, fPSA, AFP, and ferritin), hormones (cortisol, DHEA-S, insulin) and vitamins (25-OHD). Linearity in the tested ranges was confirmed. Overall, this study revealed that precision criteria derived from manufacturer's claims were not satisfied for all assays while comparison study for some assays yielded differences that imply the need for additional assay evaluation prior to introduction into routine practice.

Pseudophakic Cystoid Macular Oedema (PCME) Prevention in Patients with Non-Proliferative Diabetic Retinopathy (NPDR)-Randomized Controlled Trial.

Background and Objectives: The purpose of this study was to compare the effect of topical bromfenac and dexamethasone on the intraocular concentration of interleukin 6 (IL-6) and incidence of pseudophakic cystoid macular oedema (PCME) after cataract surgery in patients with non-proliferative diabetic retinopathy (NPDR). Materials and Methods: Ninety eyes of patients with mild-to-moderate NPDR that underwent phacoemulsification cataract surgery were divided into three groups. A detailed description of the clinical study protocol is described later in paper. In short, Group 1 received topical bromfenac (0.9 mg/mL), Group 2 dexamethasone (1 mg/mL), and Group 3 placebo, both preoperatively and postoperatively. Additionally, all patients received combined topical steroid and antibiotic drops (dexamethasone, neomycin and polymyxin B) 3 weeks postoperatively. On the day of the surgery, aqueous humour samples (0.1-0.2 mL) were obtained and IL-6 concentrations were analysed. Central foveal subfield thickness (CFT) measured using spectral-domain optical coherence tomography (SD-OCT) was analysed preoperatively and postoperatively. Results: There was no significant difference in IL-6 concentrations between groups. Postoperative CFT was significantly lower in the dexamethasone group compared to the placebo group. In addition, the correlation between IL-6 and CFT was statistically significant in the dexamethasone group. No patient developed PCME in any of the three groups. No adverse events were reported during the study. Conclusion: Topical bromfenac and dexamethasone have no significant effect on intraocular IL-6 concentration in patients with NPDR. Topical bromfenac is not more effective than topical dexamethasone in reducing postoperative CFT in patients with NPDR.

Effect of adjunctive lidocaine-based scalp block and laryngotracheal local anesthesia vs general anesthesia only on plasma and cerebrospinal fluid pro-inflammatory cytokine concentrations in patients with cerebral aneurysm: a randomized controlled trial.

AIM: To compare the effect of adjunctive lidocaine-based scalp block and laryngotracheal local anesthesia vs general anesthesia only on pro-inflammatory cytokine concentrations in patients with non-ruptured brain aneurysms undergoing elective open surgery. METHODS: This parallel, randomized, controlled, open-label trial was conducted at Clinical Hospital Center Zagreb between March 2019 and March 2020. At the beginning of anesthesia, lidocaine group received 40 mg of 2% lidocaine for laryngotracheal topical anesthesia and 4 mg/kg for the scalp block. Control group underwent general anesthesia only. Plasma concentrations of IL-6, TNF-α, and IL-1ß were measured before anesthesia (S0); at the incision (S1); at the end of surgery (S2); 24 hours postoperatively (S3). Cerebrospinal fluid (CSF) cytokine concentrations were measured at the incision (L1) and the end of surgery (L2). RESULTS: Forty patients (each group, 20) were randomized; 37 were left in the final analysis. IL-6 plasma concentrations increased significantly compared with baseline at S3 in lidocaine group, and at S2 and S3 in control group. In both groups, changes in TNF-α and IL-1ß were not significant. CSF cytokine concentrations in lidocaine group did not change significantly; in control group IL-6 and IL-1ß were significantly higher at L2 than at L1. CSF IL-6 in control group significantly increased at L2, but TNF-α and IL-1ß did not. No differences in clinical outcome and complication rates were observed. CONCLUSION: Adjunctive lidocaine-based scalp block and laryngotracheal local anesthesia might attenuate CSF IL-6 concentration increase in patients with brain aneurysm.

Influence of proton pump inhibitor therapy on occurrence of voice prosthesis complications.

PURPOSE: It has been shown that the reflux of the gastric content to the proximal oesophagus influences incidence of voice prosthesis (VP) complications in laryngectomized patients. We conducted prospective randomised study to investigate the relationship between pepsin concentration in saliva and occurrence of VP complications before and after 3 months of proton pump inhibitor (PPI) therapy. METHODS: 60 laryngectomized patients with VP and 30 controls were included in the study. Saliva samples were collected in the morning and concentration of pepsin were measured by Human Pepsin (PG) ELISA kit. Thirty-Four (57%) patients reported one or more VP complication and were randomised in two groups, with and without PPI therapy, 40 mg pantoprazole per day for 3 months. RESULTS: Patients who had longer time since last VP change had higher incidence of periprosthetic and transprosthetic leakage and Candida colonisation. Pepsin was found in all saliva samples. Median saliva pepsin concentration level did not significantly differ between laryngectomized patients and control subjects, or between patients with and without VP complications, and there was no correlation between saliva pepsin concentration levels and type of VP complication. After 3 months therapy, there was no difference in median saliva pepsin level or incidence of VP complication between patients with and without PPI therapy. CONCLUSION: Although reflux was proposed to be associated with VP complications and pepsin was proven as a most sensitive and specific marker of EER, we did not find any statistically significant correlation between pepsin levels and occurrence of VP complications. A 3 months 40 mg pantoprazole therapy was ineffective in reduction of VP complications in our study group.

The levels of 12 cytokines and growth factors in tears: hyperthyreosis vs euthyreosis.

PURPOSE: Simultaneous analyses of the contents and ratios of 12 cytokines and growth factors in single samples of human tears were performed, and the results were compared between a group of healthy subjects and a group of patients with Graves' hyperthyreosis (GH) without thyroid-associated orbitopathy (TAO). METHODS: Determinations and concentration measurements of interleukins (IL-2, IL4, IL-6, IL-8, IL-10, IL-1α, and IL-1ß) interferon (IFN-γ), tumor necrosis factor (TNF-α), monocyte chemoattractant protein (MCP-1), vascular endothelial growth factor (VEGF), and epidermal growth factor (EGF) were performed with single tear samples from 21 patients with hyperthyreosis and 22 healthy subjects. The analyses were performed using a Randox microchip with an Evidence Biochip Array Analyzer. RESULTS: We found significant differences between the healthy donor group and the hyperthyreosis group in the levels of IL-6, IL-10, VEGF, IL-1α, and MCP-1. The concentration of IL-6 was considerably higher in the hyperthyreosis group, IL-10 was higher in the healthy donor group, and VEGF and MPC-1 were higher in the hyperthyreosis group. The IL-8 and IFN-γ levels were higher in the hyperthyreosis group. The ratios of all of the cytokines to anti-inflammatory IL-10 were significantly elevated in the hyperthyreosis group. CONCLUSION: There are clear differences in the levels of cytokines and growth factors in the tears of healthy subjects and patients with GH without TAO. Tear cytokine changes and related dysfunctional tear syndrome (DTS) could be an early sign of occult TAO in Graves' hyperthyreosis patients.

Serum Levels of S100A8/A9 as a Biomarker of Disease Activity in Patients with IgA Vasculitis.

S100A8/A9 protein is a well-known marker of disease activity or severity in many autoimmune and autoinflammatory diseases, but there have not been many studies about the role of S100A8/A9 in IgA vasculitis (IgAV). The aim of our study was to evaluate S100A8/A9 as a possible biomarker of activity in IgAV. We measured the serum levels of S100A8/A9 in pediatric patients with IgA vasculitis at the onset of the disease, after three months, and after six months. We compared these levels between patients with active disease, remission, and a control group, and assessed their correlation with disease activity and other markers of inflammation. Patients with active disease had significantly higher levels of serum S100A8/A9 (median ± SD) than those in the control group at the beginning of the disease (5740 ± 3157 ng/mL vs. 1447 ± 858.3 ng/mL; p < 0.0001), but also three months and six months after disease onset (p < 0.001). There was a positive correlation between S100A8/A9 serum levels and disease activity (p = 0.0003). Patients with active disease had significantly higher levels of S100A8/A9 than those in remission three months after disease onset (p = 0.0260). There was a correlation between S100A8/A9 and C-reactive protein, the C3 component of complement, ferritin, and fibrinogen. Serum levels of S100A8/A9 were also higher in patients with greater skin areas covered with rash. We demonstrated that serum levels of S100A8/A9 correlated well with disease activity and other biomarkers of inflammation in children with IgAV. According to our results, serum S100A8/A9 may be a good indicator of active disease in IgAV.

Cytoprotective effects of ß-melanocortin in the rat gastrointestinal tract.

Recently discovered anti-inflammatory and immunomodulatory properties of melanocortin peptides led to the conclusion that they might serve as new anti-inflammatory therapeutics. The purpose of this work was to examine the effectiveness of ß-melanocortin (ß-MSH) in two experimental models: ethanol-induced gastric lesions and TNBS (2,4,6-trinitrobenzenesulfonic acid)-induced colitis in male Wistar rats. Three progressive doses of ß-MSH were used: 0.125, 0.250 and 0.500 mg/kg. Our results suggest that ß-MSH acts as a protective substance in the gastric lesions model, which can be seen as a statistically significant reduction of hemorrhagic lesions at all three doses, compared to the control group. The most efficient dose was 0.250 mg/kg. Statistically significant reduction in mucosal surface affected by necrosis and the reduction of overall degree of inflammation in the colitis model indicates an anti-inflammatory effect of ß-MSH at a dose of 0.250 mg/kg. The results justify further research on ß-MSH peptide and its derivates in the inflammatory gastrointestinal diseases, and point out the possibility of using ß-MSH in studies of digestive system pharmacology.

Analysis of saliva pepsin level in patients with tracheoesophageal fistula and voice prosthesis complications.

The aim of this crossectional study was to investigate the relationship between pepsin concentration in saliva and the occurrence of tracheoesophageal fistula (TEF) complications and voice prosthesis (VP) complications, after total laryngectomy and VP implantation. We assessed the concentrations of pepsin in the saliva of 41 laryngectomized patients and correlated it with the incidence of TEF complications (periprostethic leakage, atrophy, esophageal mucosa hypertrophy, granulations, fistula enlargement, and VP dislocation), VP complications (transprosthetic leakage, Candida infection) and voice quality. Pepsin levels were measured by enzyme-linked immunoadsorbent assay (ELISA). Voice quality was assessed by Harrison-Robilard--Schultz (HRS) scale. In all, 17 (42%) patients had complications. All of them had TEF complications, whereas VP complication, together with TEF was found in 9 (22%) patients. We found no significant correlation between adjuvant radiotherapy and TEF complications. Most of patients, 30 (73%), had positive pepsin level in saliva. Median value of pepsin concentration in all patients was 4.8 (range 81.7). Median pepsin concentration was higher in patients free of TEF or VP complications (6.6, range 81.7 vs. 3.2, range 19.3) but that difference was not statistically significant (Mann-Whitney test, Z--1.562, p = 0.118). In addition, statistically insignificant negative correlation between pepsin levels and voice quality measured by HRS scale (Spearman's rho, p > 0.05). Although reflux was proposed as cause of TEF complications and pepsin has been proven as a most sensitive and specific marker of ekstraesophageal reflux, we did not find any statistically significant correlation between pepsin levels and occurrence of TEF or VP complications.

Corrigendum to: Assessment of antinuclear antibodies (ANA): National recommendations on behalf of the Croatian society of medical biochemistry and laboratory medicine.

[This corrects the article DOI: 10.11613/BM.2021.020502.].

Dramatically prolonged coagulation screening tests in a patient with positive lupus anticoagulant and monoclonal immunoglobulin M without bleeding manifestations.

BACKGROUND: Concomitant presence of lupus anticoagulant (LA) and monoclonal immunoglobulin in the same patient is uncommon and the influence of this finding on coagulation results is still unknown. CASE REPORT: We present a patient with a diagnosis of systemic lupus erythematosus (SLE) and secondary antiphospholipid syndrome (APS) with permanently positive LA who presented with accidental finding of newly discovered monoclonal IgM in a high concentration and dramatically prolonged prothrombin time (PT) and activated partial thromboplastin time (aPTT), without bleeding manifestations. CONCLUSION: Concomitant presence of extremely prolonged PT and aPTT with unusual coagulation reaction kinetics, consistent LA ratio over the follow-up period and normalization of coagulation screening results with decreasing monoclonal IgM concentration elicited suspicion that PT and aPTT prolongation could be attributed to M-protein with antiphospholipid specificity. Low LA-sensitive aPTT reagent Actin FS demonstrated exceptional sensitivity, whereas human placental thromboplastin in contrast to recombinant reagents showed significantly lower sensitivity to monoclonal IgM with antiphospholipid specificity. Changes in the activity of SLE observed during the follow-up period were inversely related to monoclonal IgM concentration, while the presence of secondary APS was consistent. Described analytical interference on PT and aPTT without bleeding manifestation should point towards suspicion of previously unidentified monoclonal IgM with antiphospholipid sensitivity.

Autoantibodies in Sjögren's syndrome and its classification criteria.

Sjögren's syndrome (SS) is a systemic autoimmune disease characterized by immune-mediated injury of exocrine glands. Extensive lymphocytic infiltrates may contribute to the destruction and loss of secretory function of glands. B-cell hyperactivity is a key feature of the disease resulting in the production of a diverse array of autoantibodies in these patients. Although not specific for SS, anti-Ro/SSA and anti-La/SSB antibodies have been useful biomarkers for disease classification and diagnosis. During recent years, novel autoantibodies have been discovered in SS. In this review, we summarize the historical role and clinical relevance that autoantibodies have played in the classification criteria of Sjögren's syndrome, discuss laboratory aspects in antibody detection and review the role of novel autoantibodies in predicting particular stages of the disease, clinical phenotypes and long-term complications.

Urinary brain-derived neurotrophic factor and nerve growth factor as noninvasive biomarkers of overactive bladder in children.

Introduction: Overactive bladder (OAB) is the most common urinary disorder and the leading cause of functional daytime intermittent urinary incontinence in children. The aim of this study was to determine whether urinary brain-derived neurotrophic factor (BDNF) and nerve growth factor (NGF) concentrations, normalized to urine creatinine, could be used as biomarkers for diagnosis and treatment monitoring of OAB in children. Materials and methods: Urine samples of 48 pediatric patients with OAB were collected at the start of anticholinergic therapy (baseline), at follow-up visits (3 and 6 months), and from 48 healthy controls. Urinary BDNF and NGF concentrations were determined by ELISA method (Merck, Darmstadt, Germany) and Luminex method (Thermo Fisher Scientific, Waltham, USA). Differences of frequency between quantifiable analyte concentrations between subject groups were determined using Fisher's exact test. Results: There was no statistically significant difference between quantifiable analyte concentrations between patients at baseline and the control group for BDNF and NGF by either the ELISA or Luminex method (P = 1.000, P = 0.170, P = 1.000, and P = N/A, respectively). There was a statistically significant difference between quantifiable BDNF by the ELISA method between patients at baseline and complete success follow-up (P = 0.027), while BDNF by Luminex method and NGF by both methods were not statistically significant (P = 0.078, P = 0.519, and P = N/A, respectively). Conclusions: This study did not demonstrate that urinary BDNF and NGF concentrations, can be used as biomarkers for diagnosis and therapy monitoring of OAB in children.

Properties of Uncommon Indirect Immunofluorescence Staining Patterns Determined during Antinuclear Antibody Detection on HEp-2 Cells.

In this study, we aimed to assess the prevalence of uncommon staining patterns found during testing for the presence of antinuclear antibodies (ANA) and to determine their association with certain antibodies and clinical diagnoses. Presence of ANA and the staining pattern was determined in 10955 samples using indirect immunofluorescence (IIF) on HEp-2 cells. ANA-positive samples were assessed for presence of 14 specific antibody types using a microbead based system. Demographic data (age, sex) and clinical diagnoses were collected from the referral documentation. Particular staining patterns were then compared with a representative comparison group comprised of samples with common staining patterns using these criteria. There were 22 patterns present in less than 3% of samples each and these were jointly present in 42.43% of ANA-positive samples. Specific antibodies were found in proportions similar to the comparison group (46.06%) and varied significantly between patterns. Likewise, there were significant differences in antibody distribution in particular patterns. Some patterns were associated with presence of rheumatic diseases or inflammatory arthropathies, while in others there was a concurrent diagnosis of liver disease, or a neoplastic process. Many of the uncommon IIF patterns have distinctive characteristics that warrant further investigation in order to determine their role in diagnosing various diseases, not limited only to the illnesses of the rheumatic spectrum. IIF on HEp-2 cells remains an irreplaceable method because of the diversity of ANA, only a number of which can be detected using other standardised methods.