Antibody-negative Group Research Articles

Clinical characteristics of psoriatic arthritis with positive rheumatoid factor or anti-cyclic citrullinated peptide antibody

To analyze the clinical and laboratory features of psoriatic arthritis (PsA) patients with positive rheumatoid factor (RF) or anti-cyclic citrullinated peptide (CCP) antibody. In the study, 77 PsA patients who were hospitalized in the Department of Rheumatology and Immunology of Peking University Third Hospital from January 2007 to June 2019 were enrolled. All the patients met Classification Criteria for Psoriatic Arthritis or Moll or Wright Criteria. Rheumatoid factor (RF) and anti-cyclic-citrullinated peptide (CCP) antibody were tested in these patients. According to whether anti-CCP antibody or RF was detected in serum, all the patients were divided into anti-CCP antibody or RF positive group (15 cases), anti-CCP antibody or RF negative group (62 cases). According to the detection of anti-CCP antibody in serum, all the patients were divided into anti-CCP antibody positive group (7 cases) and anti-CCP antibody negative group (70 cases). Clinical and laboratory data were collected. The differences of clinical and laboratory indicators between the RF or anti-CCP antibody positive and negative PsA patients were compared. Clinical and laboratory indicators between the anti-CCP antibody positive and negative patients were also compared. Among the 77 patients, 15 were RF or anti-CCP antibody positive, of whom 8 were only RF positive and 2 were only anti-CCP antibody positive, and both of RF and anti-CCP antibody were positive in 5 cases. The RF or anti-CCP antibody positive PsA patients were older than those in the negative group [(58.2±14.8) years vs. (46.69±12.27) years, P=0.002]. And metacarpophalangeal joints, elbow joints and shoulder joints were more likely to be involved in RF or anti-CCP antibody positive PsA patients. PsA patients in the anti-CCP antibody positive group were older than those in the negative group [(62.43±14.34) years vs. (47.59±12.75) years old, P=0.005]. The positive rate of RF and serum level of fibrinogen in the anti-CCP antibody positive group were higher than those in the negative group. The PsA patients in the anti-CCP antibody positive group were all polyarthritis, while 68.6% patients in the negative group were polyarthritis, but there was no statistical difference between the two groups. There was no statistical difference in sausage fingers/toes, changes in nails and enthesitis, and bone erosion on radiographs between the RF or anti-CCP antibody positive and negative PsA patients. There was also no statistical difference in sausage fingers/toes, bone erosion on radiographs, and changes in nails and enthesitis between the anti-CCP antibody positive and negative patients. RF and anti-CCP antibodies can be detected in the serum of some PsA patients. RF or anti-CCP antibody positive PsA patients were older than those in negative PsA patients. Metacarpophalangeal joints, elbow joints and shoulder joints were more likely to be involved in RF or anti-CCP antibody positive PsA patients. Anti-CCP antibody positive PsA patients were older and had higher levels of RF positive rate and fibrinogen level.

Anti-Phospholipase A2 Receptor (Anti-PLA2R) Antibody in Diagnosis and Treatment of Idiopathic Membranous Nephropathy: A Single-Center Observational Study in China.

BackgroundThe aim of this study was to observe the concentration of serum anti-PLA2R antibody in idiopathic membranous nephropathy (IMN) patients and analyze its relationship with clinical and laboratory parameters.Material/MethodsWe treated 72 patients with idiopathic membranous nephropathy diagnosed by renal biopsy; all these patients who presented nephrotic syndrome were enrolled for investigation, and then underwent combination therapy with prednisone and cyclosporine A for 6 months. We collected data on 24-h total proteinuria (TUpro), creatinine clearance rate (Ccr), and serum albumin (Alb) levels before and after immunosuppressive treatment. Serum anti-PLA2R antibody was measured by enzyme-linked immunosorbent assay (ELISA).ResultsFifty-six out of 72 IMN patients presented positive serum anti-PLA2R antibody. The titer of anti-PLA2R antibody was significantly correlated with both TUpro and serum Alb levels of pre- and post-therapeutic values in IMN (P<0.05), but did not have a relationship with Ccr (P>0.05). In comparison with the anti-PLA2R antibody-negative group, there were significantly higher TUpro and lower Alb levels in the anti-PLA2R antibody-positive group (P<0.05). However, Ccr was comparatively lower in the anti-PLA2R antibody-positive group, but the difference was not statistically significant (P>0.05). There were 24 patients with negative anti-PLA2R antibody and 14 patients had complete remission in the positive anti-PLA2R antibody group, while anti-PLA2R antibody of all 14 patients became negative. Eight out of 16 patients without anti-PLA2R antibody went into complete remission.ConclusionsSerum anti-PLA2R antibody, as determined by non-invasive technique, is a specific biomarker for diagnosis of IMN. Our results suggest that serum anti-PLA2R antibody has great potential to guide clinical diagnosis and treatment, as well as prognosis determination, in IMN patients.

The Effect of Hepatitis B Virus Antibody on Clinical Outcome and Prognosis in Patients with Diffuse Large B-Cell Lymphoma

Introduction: Diffuse large B-cell lymphoma (DLBCL), the most common subtype of non-Hodgkin lymphoma (NHL), is strongly correlated with virus infection and host immunity status. To date, several kinds of virus infection have been involved in the tumorigenesis and progression of NHL, such as Epstein-Barr virus, hepatitis C virus, human immunodeficiency virus and so on. Hepatitis B virus (HBV) infection is a significant public health problem around the world, especially in China. HBV infection has been found to have an epidemiologic association with NHL and HBsAg status has been shown to be associated with the clinical feature and prognosis of DLBCL patients. However, no literature has been reported regarding the effect of HBV antibody in DLBCL. This study was to evaluate the impact of HBV antibody status on clinical outcome and prognosis in DLBCL patients. Methods: In this retrospective study, we investigated the clinical data of 190 patients with newly diagnosed and untreated DLBCL, who had received histological diagnosis and standard treatment at Shandong Provincial Hospital from May 2013 to May 2018. 127 DLBCL patients were effectively followed up to September 2018. Various statistical analyses were used to determine the significance of HBV antibody status in DLBCL patients. Results: The prevalence of HBsAg, HBsAb and HBcAb were increased in DLBCL patients compared with that in general Chinese population (Table 1).Compared with HBeAb-negative patients, HBeAb-positive patients displayed unique clinical features, such as more advanced disease stage (p=0.031) and higher International Prognostic Index (IPI) score (p=0.015, Table 2). Besides, patients in HBsAb-positive group displayed younger onset age (Figure 1). Patients in HBV antibody-negative group had better therapeutic efficiency than the positive group (Table 3), including HBsAb (p=0.013), HBeAb (p=0.013), combined HBsAb and HBcAb (p=0.019). The media progression-free survival (PFS) of HBeAb-positive group (p=0.004), HBcAb-positive group (p=0.038), HBsAb-positive and HBcAb-positive group (p=0.008) and the media overall survival (OS) of HBeAb-positive group (p=0.007), HBcAb-positive group (p=0.103), HBsAb-positive and HBcAb-positive group (p=0.035) were shorter than the negative group, respectively (Figure 2). We found the positive association between the expression of CD21 and HBsAb status (p=0.06, Table 4), both of which had no statistical significance in prognostic prediction. However, the media PFS (p=0.035) and OS (p=0.079) of patients with positive HBsAb and positive CD21 expression were worse than the negative group (Figure 3). Patients in Rituximab-containing group had better therapeutic efficiency (p=0.05), better PFS (p=0.015) and OS (p=0.008) than patients in Rituximab-free group (Figure 4). Interestingly, there were significant differences of Rituximab effect on clinical prognosis depending on the status of HBV antibody (Figure 5 and 6). For example, the positive effect of Rituximab on PFS (p=0.019) and OS (p=0.001) in HBsAb-positive patients was statistically significant while no difference was observed in PFS (p=0.251) and OS (p=0.987) in HBsAb-negative patients. In HBcAb-positive group, patients with Rituximab had better PFS (p=0.019) and OS (p=0.004) than patients without Rituximab. However, for HBcAb-negative patients, the PFS (p=0.596) and OS (p=0.80) were similar in Rituximab-containing group and Rituximab-free group. Similarly, the PFS (p=0.004 vs p=0.479) and OS (p&lt;0.001 vs p=0.936) according to the use of Rituximab displayed significant difference in HBsAb-positive and HBcAb-positive group rather than the negative group. Conclusions: The prevalence of HBV was increased in DLBCL patients and patients with positive HBV antibody displayed unique clinical features. Our investigations identified for the first time that HBV antibody had a negative effect on clinical outcome and prognosis in DLBCL patients. Interestingly, the effect of Rituximab in prognostic prediction was more significant in HBV antibody-positive group than the negative group. Therefore, our findings lead to a novel understanding of the association between HBV antibody and DLBCL development and provide promising factors for the prognostic prediction in DLBCL patients. Disclosures No relevant conflicts of interest to declare.

Early typing diagnostic and predictive value of AKA, APF and ACPA in juvenile idiopathic arthritis

Objective To investigate the early typing diagnostic and predictive value of anti-keratin antibodies(AKA), anti-perinuclear factor(APF) and anti-citrullinated protein antibodies(ACPA) in patients of juvenile idiopathic arthritis (JIA). Methods A retrospective study was conducted to collect 144 cases of JIA who were hospitalized in Capital Institute of Pediatrics from December 2013 to June 2016 and followed up for at least one year.Among them,66 were males (46%) and 78 were females (54%).The age at diagnosis was between 1 year 5 months to 15 years 9 months.144 patients were tested for AKA,ACPA,APF and TNFα upon admission. Chi-square test or Fisher exact test were used to compare the positive rates of three antibodies among different subtypes. Mann-Whitney nonparametric test and Chi-square test or Fisher exact test were used to analyze the data of prognosis between antibody-positive group and antibody-negative group in the course of disease. Results In 144 patients, 49(34%) were classified as systemic arthritis, 28 (19.4%) as polyarthritis, 61(42.3%) as oligoarthritis, and 6(4.2%) as enthesitis-associated arthritis. 52 cases (36.1%) were positive for one antibody or more antibodies of AKA/APF/ACPA at the early stage, 14(9.7%) were AKA positive, 44(30.6%) were ACPA positive and 12(8.3%) were APF positive. The positive rates of ACPA/AKA/APF antibodies were significantly different among different subtypes(χ2=33.863,26.860,14.395; P<0.01,<0.01,<0.05).The rates in polyarthritis were higher than those in systemic arthritis and oligoarthritis; In 95 children with non-systemic form, the level of TNFα in antibody-positive group (43 cases) was higher than that in antibody-negative group (52 cases) at the early stage(Z=4.785, P<0.01);144 patients were followed up for at least one year,the rates of patients who accepted biologic therapies were significantly different between antibody-positive group and antibody-negative group (50% vs 25%). So do the rates of patients with joint deformities (17.3% vs 2.2%) and with important joints involvement (hip and axis joints) (59.6% vs 14.1%) (χ2=9.249,10.875,32.392; P<0.01,<0.01,<0.01). Further more, the number of joints involved in the antibody-positive group (7.07±3.85) was significantly more than that in the antibody-negative group (2.31±1.64) (F=63.822, P<0.01). Conclusions AKA,APF and ACPA are important in the early typing diagnosis of JIA,and may be closely related to the prognosis of patients with JIA. Key words: Arthritis, juvenile; Keratins; Autoantibodies; Antibodies, Antinuclear; Anti-citrullinated protein antibodies; Early diagnosis; Prognosis

Circulating metabolites in progression to islet autoimmunity and type 1 diabetes

Aims/hypothesisMetabolic dysregulation may precede the onset of type 1 diabetes. However, these metabolic disturbances and their specific role in disease initiation remain poorly understood. In this study, we examined whether children who progress to type 1 diabetes have a circulatory polar metabolite profile distinct from that of children who later progress to islet autoimmunity but not type 1 diabetes and a matched control group.MethodsWe analysed polar metabolites from 415 longitudinal plasma samples in a prospective cohort of children in three study groups: those who progressed to type 1 diabetes; those who seroconverted to one islet autoantibody but not to type 1 diabetes; and an antibody-negative control group. Metabolites were measured using two-dimensional GC high-speed time of flight MS.ResultsIn early infancy, progression to type 1 diabetes was associated with downregulated amino acids, sugar derivatives and fatty acids, including catabolites of microbial origin, compared with the control group. Methionine remained persistently upregulated in those progressing to type 1 diabetes compared with the control group and those who seroconverted to one islet autoantibody. The appearance of islet autoantibodies was associated with decreased glutamic and aspartic acids.Conclusions/interpretationOur findings suggest that children who progress to type 1 diabetes have a unique metabolic profile, which is, however, altered with the appearance of islet autoantibodies. Our findings may assist with early prediction of the disease.

Clinical Characterization of Definite Autoimmune Limbic Encephalitis: A 30-case Series.

Objective Limbic encephalitis (LE) is an inflammatory condition of the limbic system that has an acute or subacute onset. Several types of antibodies are related to the onset of LE, including anti-N-methyl D-aspartate receptor (NMDAR) antibodies and voltage-gated potassium channel (VGKC)-complex antibodies. However, the characteristics and prevalence of LE remain unclear, especially in Asian cohorts, due to the rarity. We aimed to survey their characteristics. Materials and Methods Data of 30 cases clinically defined as “definite autoimmune LE” (based on the standard criteria) were retrospectively collected. These patients were categorized into four subtypes: NMDAR (+) (n=8), VGKC (+) (n=2), antibodies related to paraneoplastic syndrome (n=2), and an antibody-negative group (uncategorized) (n=18). Results LE is rare in Japan, and affected only 30 of 16,759 hospital patients (0.2%) over a ten-year period. The NMDAR (+) group showed distinctive symptoms, while the other three groups had similar indications. Brain MRI indicated significant medial temporal lobe atrophy at one year follow up after discharge. The prevalence of cognitive dysfunction as a complication was 64% (9/14). First-line immunotherapy resulted in a good outcome. A drastic improvement was seen from 4.0±1.1 to 1.1+ on the modified Rankin Scale. A good treatment outcome was observed in all groups (NMDAR, VGKC, and uncategorized), suggesting the importance of an early clinical diagnosis and the early initiation of treatment. Furthermore, we reviewed 26 cases that were clinically diagnosed as definitive autoimmune LE in previous case reports. Conclusion Our findings show that the establishment of a clinical diagnosis based on the clinical criteria of definitive autoimmune LE is important for the initiation of immunotherapy.

Reduced Anti-Histone Antibodies and Increased Risk of Rheumatoid Arthritis Associated with a Single Nucleotide Polymorphism in PADI4 in North Americans.

Autoantibodies against citrullinated proteins are a hallmark of rheumatoid arthritis, a destructive inflammatory arthritis. Peptidylarginine deiminase 4 (PAD4) has been hypothesized to contribute to rheumatoid arthritis by citrullinating histones to induce neutrophil extracellular traps (NETs), which display citrullinated proteins that are targeted by autoantibodies to drive inflammation and arthritis. Consistent with this theory, PAD4-deficient mice have reduced NETs, autoantibodies, and arthritis. However, PAD4′s role in human rheumatoid arthritis is less clear. Here, we determine if single nucleotide polymorphism rs2240335 in PADI4, whose G allele is associated with reduced PAD4 in neutrophils, correlates with NETs, anti-histone antibodies, and rheumatoid arthritis susceptibility in North Americans. Control and rheumatoid arthritis subjects, divided into anti-cyclic citrullinated peptide (CCP) antibody positive and negative groups, were genotyped at rs2240335. In homozygotes, in vitro NETosis was quantified in immunofluorescent images and circulating NET and anti-histone antibody levels by enzyme linked immunosorbent assay (ELISA). Results were compared by t-test and correlation of rheumatoid arthritis diagnosis with rs2240335 by Armitage trend test. NET levels did not significantly correlate with genotype. G allele homozygotes in the CCP− rheumatoid arthritis group had reduced anti-native and anti-citrullinated histone antibodies. However, the G allele conferred increased risk for rheumatoid arthritis diagnosis, suggesting a complex role for PAD4 in human rheumatoid arthritis.

Antinuclear Antibody-Negative Systemic Lupus Erythematosus in an International Inception Cohort.

The spectrum of antinuclear antibodies (ANAs) is changing to include both nuclear staining as well as cytoplasmic and mitotic cell patterns (CMPs) and accordingly a change is occurring in terminology to anticellular antibodies. This study examined the prevalence of indirect immunofluorescence (IIF) anticellular antibody staining using the Systemic Lupus International Collaborating Clinics inception cohort. Anticellular antibodies were detected by IIF on HEp-2000 substrate using the baseline serum. Three serologic subsets were examined: ANA positive (presence of either nuclear or mixed nuclear/CMP staining), anticellular antibody negative (absence of any intracellular staining), and isolated CMP staining. The odds of being anticellular antibody negative versus ANA or isolated CMP positive was assessed by multivariable analysis. A total of 1,137 patients were included; 1,049 (92.3%) were ANA positive, 71 (6.2%) were anticellular antibody negative, and 17 (1.5%) had an isolated CMP. The isolated CMP-positive group did not differ from the ANA-positive or anticellular antibody-negative groups in clinical, demographic, or serologic features. Patients who were older (odds ratio [OR] 1.02 [95% confidence interval (95% CI) 1.00, 1.04]), of white race/ethnicity (OR 3.53 [95% CI 1.77, 7.03]), or receiving high-dose glucocorticoids at or prior to enrollment (OR 2.39 [95% CI 1.39, 4.12]) were more likely to be anticellular antibody negative. Patients on immunosuppressants (OR 0.35 [95% CI 0.19, 0.64]) or with anti-SSA/Ro 60 (OR 0.41 [95% CI 0.23, 0.74]) or anti-U1 RNP (OR 0.43 [95% CI 0.20, 0.93]) were less likely to be anticellular antibody negative. In newly diagnosed systemic lupus erythematosus, 6.2% of patients were anticellular antibody negative, and 1.5% had an isolated CMP. The prevalence of anticellular antibody-negative systemic lupus erythematosus will likely decrease as emerging nomenclature guidelines recommend that non-nuclear patterns should also be reported as a positive ANA.

1683-P: Analysis of Type 1 Diabetes Genetic Risk Score Shows 1 in 8 People with Clinically Diagnosed Adult-Onset T1D Are Misdiagnosed, and Presenting Features at Diagnosis Do Not Identify Those Misdiagnosed

Aims: Accurate initial diagnosis of adult-onset type 1 diabetes (T1D) is important. We aimed to estimate the rate of misdiagnosis in clinically-diagnosed adult T1D. We also assessed the utility of Islet autoantibodies and presenting features to identify misdiagnosed-T1D. Methods: We used a T1D-genetic risk score (T1D-GRS) to estimate misdiagnosed-T1D in 1112 white-Europeans adults clinically-diagnosed with T1D (age diagnosis &amp;gt;18y) from the ADDRESS-2 study. We used 1924 gold-standard T2D as a non-T1D control. All patients were recruited &amp;lt;6m from diagnosis and insulin treated. We assessed clinical features and autoantibodies (GADA, IA-2A, ZNT8A) in misdiagnosed and true-T1D. Results: People with one (n=309), two (n=285) or three (n=300) autoantibodies had a similar T1D-GRS suggesting people with ≥1 antibody positive had true-T1D (mean GRS 0.270 vs. 0.269 vs. 0.273, p=0.13). People without antibody had T1D-GRS (0.243, n=218) between true-T1D (0.271, n=894, ≥1ab+ve) and T2D (0.229, n=1924, p&amp;lt;0.0001) suggesting presence of non-T1D in antibody negative group. The estimated proportion of non-T1D in antibody negative group was 67% (n=146/218) which was 13% of the whole cohort (95% CI 11-15%). Misdiagnosis was higher in people diagnosed 30-75y (21%) vs. 18-30y (6%, p&amp;lt;0.001). Misdiagnosed-T1D and true-T1D had similar rates of polyuria (91% vs. 95%), weight loss (85% vs. 88%) and DKA (38% vs. 43%) (all p&amp;gt;0.05). Misdiagnosed-T1D were more likely to be male (81% vs. 59%), older (40y vs. 32y), had higher BMI (28 vs. 24) and HbA1c (105 vs. 91 mmol/mol) compared to true-T1D (all p&amp;lt;0.001). Conclusion: Initial misdiagnosis of T1D is common in people diagnosed &amp;gt;30y (21%). When clinically-diagnosed with T1D at diagnosis, negative islet autoantibodies but not severe hyperglycaemia/DKA identify misdiagnosed people. Disclosure K.A. Patel: None. N. Thomas: None. M.N. Weedon: None. H.C. Walkey: None. A. Kaur: None. A.J. Williams: None. S. Misra: None. N. Oliver: Advisory Panel; Self; Roche Diabetes Care. Research Support; Self; Dexcom, Inc., Roche Diabetes Care. Speaker's Bureau; Self; Dexcom, Inc., Sanofi. D.G. Johnston: None. A.T. Hattersley: None. Funding Diabetes UK; JDRF; Diabetes Research &amp; Wellness Foundation

Relationship between infection of Toxoplasma gondii and metabolic syndrome

Objective To investigate the relationship between Toxoplasma gondii (T.gondii) infection and metabolic syndrome (MS). Methods A total of 20 577 patients who received serum test of anti-T.gondii IgG antibody in the National Health and Nutrition Examination Survey (NHANES) of the United States from 2009 to 2014 were collected to analyze the clinical features of anti-T.gondii IgG antibody positive patients, and to compare metabolic related indicators in the antibody IgG positive and negative groups. The independent sample t-test, chi-square test, and logistic regression analysis were used to explore the risk factors of MS. Results A total of 2 746 participants were positive for the T. gondii antibody (13.34%), with a higher prevalence of male (14.44% vs 12.27%, χ2=15.99, P< 0.01). Meanwhile, the prevalence of T. gondii increased with age and body mass index (BMI) (χ2=979.98 and 50.85, respectively, both P<0.01). Among the 2 191 patients with MS, 449 (20.49%) patients were positive for T. gondii. While 2 297(12.49%) patients were anti-T.gondii positive in 18 386 non-MS patients. The difference was statistically significant (χ2=78.504, P<0.01). Age (t=-37.37), BMI (t=-4.28), glycosylated hemoglobin (t=-11.81), fasting blood glucose (t=-9.38), triacylglycerol (t=-6.32), cholesterol (t=-7.16), serum uric acid (t=-5.25) and serum creatinine (t=-7.69) in the seropositive group were all higher than those in the seronegative group (all P<0.01). After adjusting for age and gender, the prevalence of T. gondii was an independent risk factor for MS (odds ratio [OR]=1.147, P=0.023). Conclusions BMI, blood lipids, blood uric acid and blood glucose are significantly increased in patients with T. gondii infection. T. gondii infection is an independent risk factor for MS. Key words: Metabolic syndrome; Risk factors; Toxoplasma gondii

Tacrolimus Variability: A Cause of Donor-Specific Anti-HLA Antibody Formation in Children.

The most important determinant of long-term graft survival in renal transplantation is adequate immunosuppression. Inadequate immunosuppression may lead to graft loss due to the presence of anti-HLA antibody. The aim of this study was to investigate the effect of variability in tacrolimus blood concentration on anti-HLA antibody development in pediatric recipients of living-donor renal transplants. Pediatric recipients of living-donor renal transplants were retrospectively evaluated. Patients with a minimum of two years of follow-up who were administered tacrolimus were included in the study. Patients who had pretransplant anti-HLA antibody were excluded. Variability in tacrolimus blood concentration was assessed using the coefficient of variation ("tacrolimus CV") method. Tacrolimus CV was calculated separately for the first 6months post-transplant, between 6 and 12months post-transplant, and from the end of the first year post-transplant to the last follow-up. We constructed receiver operating characteristic (ROC) curves of the tacrolimus CV for each group to find the best cutoff value. A total of 67 patients (including 48 males; 72%) with a mean age of 15.16 ± 4.43years were included in the study. Anti-HLA antibody positivity was detected in 12 patients (18%). More than three HLA mismatches and the presence of acute cellular rejection correlated with the development of anti-HLA antibody (p = 0.056, 0.009). Tacrolimus CVs for the three periods were 0.37 ± 0.11, 0.31 ± 0.18, and 0.35 ± 0.12, respectively. The cutoff value of tacrolimus CV for anti-HLA antibody development was calculated as 0.32 with a sensitivity of 90.91% and specificity of 50.94% [AUC (area under the curve) 0.713, p = 0.023]. During the second 6-month period and after a year post-transplant, the percentage of patients with tacrolimus CV >0.32 was significantly higher in the anti-HLA antibody positive group than in the antibody negative group (67% vs 31%, p = 0.027; 83% vs 47%, p = 0.033). The eGFR (estimated glomerular filtration rate) was similar for the anti-HLA antibody negative and positive groups (78.72 ± 2.86 vs 77.45 ± 8.08, p > 0.05). High tacrolimus concentration variability appears to be associated with anti-HLAantibody formation in pediatric recipients of living-donor renal transplants.

Serum phospholipase A2 receptor antibodies and immunoglobulin G subtypes in adult idiopathic membranous nephropathy: Clinical value assessment

BackgroundIdiopathic membranous nephropathy (IMN) is widely considered as an organ-specific autoimmune disorder. Implicated in its pathogenesis are the phospholipase A2 receptors (PLA2R) expressed on glomerular podocytes against which serum antibodies are formed. In this study we quantified and assessed the clinical value of total serum PLA2R antibodies and the subtype antibodies in IMN. MethodsWe measured serum levels of total PLA2R antibodies and IgG subtype antibodies by Enzyme Linked Immunosorbent Assay (ELISA) in 146 biopsy-proven IMN patients, 51 non-IMN patients and 62 healthy controls. We went ahead and determined the diagnostic potential of total serum PLA2R antibodies and assessed if a relationship exists between the dominat subtype antibody and the clinical parameters. ResultsThe diagnostic sensitivity and specificity of total serum PLA2R antibody for IMN were found at 69.9% and 100% respectively. Significant differences in systolic blood pressure, serum Cystatin C, serum albumin and estimated glomerular filtration rate (eGFR) were found between the antibody-positive and antibody-negative groups of IMN patients. Subtype antibody 4 and 1 exhibited the highest positive rates of 94.4% and 91.6% respectively. The mean serum proportion of subtype antibodies was 65.4, 12.7, 7.6 and 4.6% for subtype 4, 1, 3 and 2 respectively. Serum levels of total protein and albumin were significantly decreased among patients with high serum titres of antibody subtype 4. ConclusionOur findings underscore the diagnostic potential of total serum PLA2R antibodies and highlight the importance of antibody subtype 4 over other subtype antibodies in IMN.

Do Immune-Mediated TTP Patients Presenting with No Detectable ADAMTS13 Antibody Represent a Unique Clinical Phenotype?

Background:Immune-mediated thrombotic thrombocytopenic purpura (iTTP) is characterised by antibody mediated activity against ADAMTS13. Prompt diagnosis and treatment is critical in this rare condition which has an untreated mortality of around 90%. An ADAMTS13 activity level of <10% is consistent with a diagnosis of TTP and for a significant proportion of patients, ADAMTS13 antibodies can also be demonstrated, confirming iTTP. Recent literature suggests that the sub-group of patients with low ADAMTS13 antigen levels and high ADAMTS13 antibody have the highest mortality (Ferras et al., Blood 2017.); however, the sub-group of patients who have never had a detectable inhibitor remain poorly defined. With therapies becoming increasingly available as adjuvants to plasma exchange, in addition to elective agents for suspected relapsing disease, there is a need to better risk stratify this heterogeneous patient group and identify which patients may benefit most from additional therapies. In most literature to date, patients with low ADAMTS13 inhibitor levels have been excluded from further data analysis and therefore remain an under-represented population. Aim: To define the characteristics of the iTTP patient sub-group where an ADAMTS13 inhibitor has never been demonstrated throughout their clinical course Methods: This was retrospective study of data from a single UK TTP tertiary referral centre from 2011 to 2018. Inclusion criteria for patients with iTTP included ADAMTS13 activity ≤10% at acute presentation. Patients with congenital TTP were excluded from data analysis. A positive ADAMTS13 antibody was defined as >12 U/ml using the Technoclone ADAMTS13 inhibitor ELISA assay. Data collected included patient demographics, presenting symptoms, laboratory markers at first presentation, ADAMTS13 activity and antibody and number of relapses. Clinical relapse was defined as reappearance of clinical manifestations or laboratory parameters consistent with acute TTP and serological relapse was defined as ADAMTS13 activity of <15%. Patients with no detectable antibody were compared with a like group of TTP patients with a detectable ADAMTS13 antibody. Results: A total of 61 patients and 72 acute patient episodes were analysed, of which 7 patients had never demonstrated an ADAMTS13 inhibitor in 10 acute episodes. This sub-group was subsequently compared to an equal sample size of patients with a detectable ADAMTS13 antibody and similar demographics. The average antibody level for the antibody negative group was 5.8 U/ml (range 3 - 10 U/ml) compared to 98.7 U/ml (range 37 - 147U/ml) in the antibody positive group. The respective average ADAMTS13 activity was 4.5% (0-10%), compared with 0.3% (0-1%). 100% of the patients in the antibody positive group had neurological symptoms at presentation compared with 43% of the patients with no detectable antibody. The average presenting platelet count and Troponin T for the antibody negative cohort was 27 x 109/L and 21 ng/L respectively; compared with 10 x 109/L and 206 ng/L in the antibody positive group. 43% of patients in the antibody negative group had multiple acute clinical relapses (1-3) compared with 0% patients presenting with a detectable antibody. 14% of the antibody positive group had a serological relapse treated with elective Rituximab compared with 43% of the patients in the antibody negative group. Conclusion: This data specifically reports the apparent characteristics of patients with ADAMTS13 antibody negative iTTP. Up to 10% of patients may never demonstrate an inhibitor against ADAMTS13 and appear to have a less severe clinical presentation with fewer neurological and cardiac manifestations. This study further suggests that this sub-group may represent a more ‘grumbling‘/ relapsing phenotype with a tendency for more frequent clinical or serological relapse of TTP. Although TTP is rare, further study of this sub-population of iTTP patients is important in risk stratification, and to support treatment decisions, in particular towards preventing future relapse. DisclosuresNo relevant conflicts of interest to declare.

Relationship between thyrotropin and urine iodine in Han and Uygur nationalities pregnancy women in People's Hospital of Xinjiang Uygur Autonomous Region

Objective: To investigate the relationship between thyrotropin (TSH) and urine iodine in pregnant women of Han and Uygur ethnic groups in People's Hospital of Xinjiang Uygur Autonomous Region. Methods: A total of 1 568 pregnant who completed screening of TSH and urine iodine in People's Hospital of Xinjiang Uygur Autonomous Region hospital from August 2014 to December 2017 were included in the study, 956 cases were Han and the other 612 were Uygur. Basic clinical data, serum TSH, thyroid peroxidase autoantibody (TPOAb) , and urine iodine levels were retrospectively analyzed. Results: (1) General results: The median urine iodine level was 162.6 μg/L (53.4-539.3 μg/L) , and the distribution of urine iodine classification was iodine deficiency 42.9% (672/1 568) , iodine appropriate 36.7% (576/1 568) , iodine slightly high 17.1% (268/1 568) and iodine excess 3.3% (52/1 568) respectively. (2) The median urine iodine levels of Han and Uygur pregnant women were 169.1 μg/L (54.6-583.4 μg/L) and 156.3 μg/L (53.1-539.3 μg/L) respectively, and the difference was statistically significant (P<0.05) .The distribution of urine iodine status in pregnancy between Han and Uygur was significantly different, which were 40.9% (391/956) vs. 45.9% (281/612) in iodine deficiency, 35.4% (338/956) vs. 38.9% (238/612) in iodine appropriate, 20.2% (193/956) vs. 12.3% (75/612) in iodine slightly high and 3.6% (34/956) vs. 2.9% (18/612) in iodine excess. (3) High serum TSH level proportion was significantly higher in Uygur ethnic group, early pregnancy, thyroid peroxidase antibody positive and anti-thyroglobulin antibody positive group when compared with Han, late pregnancy, thyroid peroxidase antibody negative and anti-thyroglobulin antibody negative groups (all P<0.05) . There were no significant differences in different age groups and iodine nutrition groups (P>0.05) . (4) There was no correlation between urinary iodine and TSH levels in all pregnant women (P>0.05) , neither in Han or Uygur group. When further stratified by gestational age, age, and antibody level, there was a positive correlation between urine iodine and serum TSH level in Han pregnant women >30 years old (P<0.05) , and there was a negative correlation in the third trimester in Uygur (P<0.05) . When serum antibody level, gestational week and age were controlled. There was no correlation between urine iodine and serum TSH level in neither group. Conclusions: (1) In Han and Uygur pregnant women, the median urine iodine level and the distribution of urine iodine classification between two ethnic groups are significantly different. (2) The correlation between urine iodine and serum TSH is not identified in Han or Uygur pregnant women.

Effects of Hepatitis C Virus Antibody-Positivity on Cardiac Function and Long-Term Prognosis in Patients With Adult Congenital Heart Disease

It was reported that hepatitis C virus (HCV) antibody-positivity adversely affects cardiac function. As the screening for HCV began in 1992, we hypothesized that HCV antibody-positive rate would be high in adult congenital heart disease (ACHD) patients who underwent heart surgery before 1992 and adversely affected cardiac function and long-term prognosis. We retrospectively enrolled 243 ACHD patients (mean age 25.9 years) who underwent cardiac surgery before 1992 and visited our hospital from 1995 to 2015. We compared clinical characteristics including cardiac function and long-term prognosis between HCV antibody-positive (n = 48) and antibody-negative (n = 195) patients. The composite end point (CEP) included cardiac death, heart failure hospitalization, lethal ventricular arrhythmias, and cardiac reoperation. The prevalence of reduced systemic ventricular ejection fraction <50% was significantly higher in the HCV antibody-positive group compared with the HCV antibody-negative group (17 vs 5.4%, p = 0.014). During a mean follow-up period of 10.1 years (interquartile range 6 to 14 years), the CEP was noted in 51 patients. Kaplan-Meier analysis showed the HCV antibody-positive group had significantly poor event-free survival than the HCV antibody-negative group (log-rank, p = 0.002). In contrast, HCV ribonucleic acid-positivity was not a significant predictor of the CEP in the HCV antibody-positive group (log-rank, p = 0.442). Furthermore, the HCV antibody-positivity was significantly associated with the CEP in both univariable and multivariable Cox regression models (hazard ratio 2.37, 95% confident interval 1.32 to 4.15, p = 0.005 and 1.96, 1.06 to 3.63, p = 0.032, respectively). In conclusion, these results suggest that more attention should be paid to HCV antibody-positivity in the management of ACHD patients.

Anti MICA Antibody (major histocompatibility complex class I related Chain A) Whether to Treat or Avoid?

Aims To study the role of MICA antibody in living renal transplantation in the absence of anti HLA antibodies. Methods A retrospective study of patients undergone living renal transplantation between 2000-2014 was performed. Recipients were classified in two groups, pre transplantation Anti MICA antibody positive group (n=17) and antibody negative comparison group (n=17). Patients with anti HLA antibodies were excluded and only isolated MICA positive patients were included in the study group. All recipients undergone tolerance protocol and post transplant T-regulatory cells, and were comparable in recipient age, donor age, donor relation, HLA and immunosuppression including induction. Results Patients with pre transplant MICA antibody positivity were associated with increased acute rejection as compared to comparison group (47% vs 11.7 %, p value= 0.02 ). Renal function in MICA positive group and comparison group were comparable over a mean follow up of 6.5 years (mean s.creatinine 1.58 vs 1.53 mg/dl ). Rate of chronic rejection was same in both groups (5.8% ). No patient or graft loss in either group over mean follow up of 6.5 years. Conclusion Isolated Anti MICA antibody positivity is uncommon event. Pre transplant anti MICA antibody positivity is associated with increased acute rejection rates. However chronic rejection rates and renal function are comparable in both groups. Thus our study emphasizes that MICA antibody positive patients may require more aggressive immunosuppression, role of desensitization has to be defined.

Neuroimaging evaluation of pattern of brain involvement in Japanese encephalitis and other viral encephalitis in paediatric age group

Introduction: Japanese encephalitis virus, a flavivirus is a significant cause of arboviral encephalitis worldwide. The virus is transmitted to humans via the bite of infected Culex mosquitoes especially C. tritaeniorhynchus, they prefer to bite outdoors and are extremely active and are extremely active in the evening and night. Neuroimaging reveals by MRI and CT scan of patients of Japanese encephalitis shows characteristic lesions particularly in the thalami, substantia nigra, basal ganglia, cerebral cortex, cerebellum, brainstem and white matter.Material &amp; Method: A total of 50 patients divided in 25 anti JE antibody positive patients and another 25 in anti JE antibody negative group. A cross sectional observational analytical study was performed in the time period of January 2015 to August 2016, the patients was studied using IgM capture ELISA and 1.5T MRI machine.Result Analysis: The results were analysed using chi square test and p values. It was found that gray matter structures were the most commonly affected, the thalamus, basal ganglia but white matter lesions were also noted. The thalamus was the most commonly involved structure, followed by the brainstem and cerebral cortex. Haemorrhagic lesions were noted in the cortex, midbrain and cerebellum.Conclusion: Involvement of the thalamus showed the most significant difference between JE and non JE patients with 64% of the JE patients showed thalamic involvement. No other part of the brain showed such significant difference.

Association of Anti Phospholipid Antibodies in The Patients With Ischemic Stroke Under 45 Years of Age In Tertiary Level Hospital: A Case Control Study

Background: Antiphospholipid antibodies have been associated with a clinical syndrome consisting of thrombosis and recurrent, unexplained fetal loss. Stroke may be caused by Antiphospholipid Antibodies (APLA) especially in young persons without other conventional risk factors like Diabetes mellitus, Hypertension, Dyslipidemia, Smoking etc. The aim of this study was to evaluate the association of antiphospholipid antibodies (Anticardiolipin antibody and lupus anticoagulant) in young ischemic stroke patients presenting with sudden neurological deficit. Materials and methods: This was a case-control study performed in Medicine and Neurology department of Chittagong Medical College Hospital, Chittagong, a tertiary care government hospital. A total no. of 195 respondents consisting of 95 consecutive young patients (Age less than 45 years) diagnosed as ischemic stroke and 100 age and sex matched healthy controls were included in this study. The clinical details and related investigations of the respondents were reviewed. Anticardiolipin antibodies (IgM, IgG isotypes) were evaluated by an Enzyme-Linked Immunosorbent Assay (ELISA) and lupus anticoagulant by phospholipid dependent coagulation test Activated Partial Thromboplastin Time (APTT). When APTT was found more than 5 sec prolonged than control value, mixing studies using a 50:50 mixture of patient and normal plasma were performed and the result was considered positive if prolongation of APTT was not corrected which were needed to be confirmed after 12 weeks. The tests of Anticardiolipin antibodies (aCL) were repeated after 12 weeks when prior results were abnormal and the tests were considered positive when both results of aCL were found above normal value (IgM &gt; 7.2 MPL/ml, IgG&gt;14.4 GPL/ml). Results: Anticardiolipin antibodies Anticardiolipin antibodies (aCL) were present in 10.5% of the patients (IgM in 3 cases, IgG in 6 cases, IgM/IgG both in 1 case) and in 1% (IgG type) of control, but none of the study subjects were found LA positive. The odds ratio of aCL was 11.647 (95% Confidence interval= 1.461 – 92.852). Overall, the risk factors profile in cases were, Hypertension (32.6%) Diabetes mellitus (10.5%) Cigarette smoking (26.3%) and Dyslipidaemia (25.3%). Among the 10 aCL positive cases, 3 were Hypertensive, 1 was Diabetic, 2 were Smoker and 2 were Dyslipidemic but anticardiolipin antibody positive group did not differ significantly with respect to distribution of major risk factor frequency from anticardiolipin antibody negative group. Conclusion: Anticardiolipin antibodies are associated significantly with ischemic stroke in young patients less than 45 years of age (p= 0.004). Hence screening for anti-cardiolipin antibodies in young patients with stroke is recommended.&#x0D; JCMCTA 2017 ; 28 (2) : 27-33

Effects of steroids on circulating follicular helper T cell-like CD4+ T cells in patients with systemic lupus erythematosus

Objective To analyze changes in the percentages of circulating follicular helper T (Tfh) cells and Tfh subsets in patients with systemic lupus erythematosus (SLE) for better understanding their relationships with SLE, and to investigate effects of steroids on circulating Tfh cells. Methods Peripheral blood mononuclear cells (PBMCs) from 27 patients with SLE (including 10 inactive patients and 17 active patients) and 21 sex- and age-matched healthy donors were analyzed by flow cytometry to detect the percentage of CD4+ CD45RA-CXCR5+ Tfh-like cells. Disease activity and the concentration of anti-double-stranded DNA (anti-dsDNA) antibody were evaluated by SLEDAI score (SLE disease activity index) and ELISA, respectively. PBMCs from healthy donors were treated with or without prednisone to evaluate its effects on circulating Tfh cells. Twelve patients with SLE were treated with high-dose steriods (200-500 mg/d, 2-3 d) and the percentages of circulating Tfh cells and Tfh subsets in them were analyzed before and after treatment. Results No significant difference in the percentage of circulating Tfh cells was observed between patients with SLE and healthy donors (P>0.05), but the percentage of Tfh17 cells in patients with SLE was significantly higher than that in healthy donors (P<0.05). Compared with patients with inactive SLE and healthy donors, patients with active SLE had a lower percentage of Tfh1 cells (P<0.05). Moreover, the percentage of Tfh1 cells was negatively correlated with SLEDAI score (r=-0.44, P<0.05). The percentage of Tfh2 cells in anti-dsDNA antibody-positive group was significantly higher than that in anti-dsDNA antibody-negative group (P<0.05). In vitro treatment of PBMCs from healthy donors with prednisone could significantly down-regulate the percentage of circulating Tfh (P<0.01), Tfh1 (P<0.05) and Tfh2 cells (P<0.01), and up-regulate the percentage of Tfh17 cells (P<0.01). In vivo treatment of patients with SLE with steriods could significantly down-regulate the percentage of circulating Tfh (P<0.01), Tfh1 (P<0.05) and Tfh2 cells (P<0.01) and up-regulate the percentage of Tfh17 cells (P<0.01). Conclusion Abnormal distribution of Tfh subsets is correlated with SLE disease activity and anti-dsDNA antibody. Steroids in the treatment of SLE could affect the percentage of circulating Tfh cells and the distribution of Tfh subsets. Key words: Systemic lupus erythematosus; Follicular helper T cell; Prednisone

The significance of anti-PLA2R antibody for the diagnosis and treatment of idiopathic membranous nephropathy

Objective To observe the expression of serum anti-PLA2R antibody and analyze its clinical significance in patients with idiopathic membranous nephropathy (IMN). Methods A total of 36 patients with nephrotic syndrome were diagnosed as IMN by renal biopsy in our hospital from April 2015 to November 2016, and enrolled in the study. All these patients were treated with prednisone and cyclosporine A for 6 months. Creatinine clearance rate(Ccr), 24-hour total proteinuria(TUpro) and plasma albumin(Alb) were collected before and after treatment. Serum anti-PLA2R antibody was also assayed by enzyme-linked immuno sorbent assay (ELISA) at the same time. All the data were prepared for statistical analysis. Results Among the 36 patients with IMN, positive serum anti-PLA2R antibody in 28(77.7%) cases were found, and there were no significant differences in age, gender, prevalence of hypertension and type 2 diabetes mellitus between anti-PLA2R antibody positive and negative groups(P>0.05). The initial and post-therapeutic values of anti-PLA2R antibody was significantly correlated with corresponding values of both TUpro and serum albumin levels, respectively(P 0.05). In comparison with anti-PLA2R antibody negative group, there were significantly higher TUpro and lower Alb levels in anti-PLA2R antibody positive group (P 0.05). Twelve patients got anti-PLA2R antibody negative and 7 patients had complete remission in anti-PLA2R antibody positive group after treatment, all the 7 patients′ anti-PLA2R antibody became negative. Fore out of eight patients without anti-PLA2R antibody entered into complete remission, accounted for 50%. The prevalence of remission in anti-PLA2R antibody negative group was higher than that in anti-PLA2R antibody positive one, but there was no statistic significance(P>0.05). Conclusions The serum anti-PLA2R antibody by non-invasive technic is a specific biomarker for diagnosis of IMN. It is of tremendous significance for serum anti-PLA2R antibody to guide clinical diagnosis and predict prognosis in IMN patients. Key words: Glomerulonephritis, Membranous; Receptors, Phospholipase A2