The validity of pathology codes for biopsy-confirmed kidney disease in the Danish National Patobank.

Background: This study validates the application of Systematized Nomenclature of Medicine second edition (SNOMED II) codes used to describe medical kidney biopsies in Denmark in encoded form, aiming to support robust epidemiological research on the causes, treatments and prognosis of kidney diseases.

Methods: Kidney biopsy reports from 1 January 1998 to 31 December 2018 were randomly extracted from the Danish National Patobank, using SNOMED codes. A 5% sample was selected, and nephrologists assessed the corresponding medical records, assigning each case the applied clinical diagnoses.

Age- and time-dependent increases in incident anti-glomerular basement membrane disease: a nationwide cohort study.

Background: Epidemiologic assessments of anti-glomerular basement membrane (GBM) disease have been challenging due to its rare occurrence. We examined changes in the incidence and outcomes from 1998 to 2018 using nationwide healthcare registries.

Methods: All patients with incident anti-GBM disease were identified using the International Classification of Diseases, 10th Revision code DM31.

Long-term cardiovascular outcomes and temporal trends in patients diagnosed with ANCA-associated vasculitis: a Danish nationwide registry study.

Objectives: To examine long-term cardiovascular outcomes and temporal trends among patients with ANCA-associated vasculitis (AAV) using Danish nationwide registries.

Methods: Using a cohort design, we examined patients with granulomatosis with polyangiitis (ICD-10: DM31.3) and microscopic polyangiitis (ICD-10: DM3.

Patient-reported outcome measures in systemic lupus erythematosus by a web-based application: A randomized, crossover, agreement study.

Objectives: Patient-reported outcome measures (PROMs) are evaluated in randomized controlled trials (RCTs) in patients with systemic lupus erythematosus (SLE), but not widely used in clinical practice. However, interest in incorporating PROMs into the management of SLE is increasing as PROMs provide a unique insight into the patient's perception of lupus disease activity. The objective was to assess agreement in PROMs answered using a web app versus an outpatient touchscreen among patients with SLE.

Increasing incidence and improved survival in ANCA-associated vasculitis-a Danish nationwide study.

Background: Anti-neutrophil cytoplasmic antibody (ANCA)-associated vasculitis (AAV) carries a high risk of morbidity and mortality, with outcomes modified by treatment and an incidence that may be increasing. We examined temporal changes in incidence and mortality during 2000-15 using nationwide healthcare registries.

Methods: Patients with incident AAV were identified using International Classification of Diseases Version 10 (ICD10) codes and grouped according to inclusion year (Period 1: 2000-04, Period 2: 2005-09, Period 3: 2010-15).

Prophylactic anticoagulation in nephrotic syndrome prevents thromboembolic complications.

Background: An increased incidence of thromboembolic events (TE) are reported in nephrotic syndrome (NS) leading to recommendations for prophylactic anticoagulation (PAC). However, as no randomized clinical trial has established the efficacy or risks associated with PAC, guidelines are empiric or substantiated only by estimates of risks and benefits. This study evaluates the risk of TE and hemorrhagic complications in patients with NS treated with PAC and compares to patients not receiving PAC.

PR3-ANCA-associated vasculitis is associated with a specific motif in the peptide-binding cleft of HLA-DP molecules.

Objectives: This study aimed to characterize the association between HLA alleles and ANCA-associated vasculitis (AAV) in a genetically homogeneous population, and to analyse the contribution of specific HLA molecule amino acid sequences to the risk of AAV.

Methods: We included 187 Danish patients with AAV and 1070 healthy controls. All were HLA typed at two-field resolution.

High levels of urinary complement proteins are associated with chronic renal damage and proximal tubule dysfunction in immunoglobulin A nephropathy.

Aim: Complement activation is involved in the pathogenesis and progression of immunoglobulin A nephropathy (IgAN); however, the clinical implication of abnormal complement protein levels in serum and urine is not clear. To address this we analyzed the correlation between disease activity and complement proteins in serum and urine from IgAN patients, and compared to patients with other types of chronic kidney disease (CKD) as well as healthy controls.

Methods: We included 85 Chinese patients with IgAN, 23 patients with non-proliferative CKD, and 20 healthy individuals.

Dominant protection from HLA-linked autoimmunity by antigen-specific regulatory T cells.

Susceptibility and protection against human autoimmune diseases, including type I diabetes, multiple sclerosis, and Goodpasture disease, is associated with particular human leukocyte antigen (HLA) alleles. However, the mechanisms underpinning such HLA-mediated effects on self-tolerance remain unclear. Here we investigate the molecular mechanism of Goodpasture disease, an HLA-linked autoimmune renal disorder characterized by an immunodominant CD4 T-cell self-epitope derived from the α3 chain of type IV collagen (α3).

The relation between histopathological classification and renal outcome, ANCA subtype and treatment regimens in ANCA-associated vasculitis.

Objectives: ANCA-associated vasculitis (AAV) is associated with an increased risk of death and end stage renal disease (ESRD). The aim of this study was to examine the correlation between a histopathological classification and renal outcome and to describe the interaction with ANCA subtype and initial treatment.

Methods: Eighty-seven patients with AAV from 1999-2010 from two centres in Denmark were included in the study and had a 3 year follow-up.

Recovery of renal function succeeding stem cell transplant: a case of C3 Glomerulonephiritis secondary to monoclonal gammopathy.

Membranoproliferative glomerulonephritis (MPGN) and C3 glomerulonephritis (C3 GN) can be secondary to monoclonal gammopathy and multiple myeloma. MPGN Type 1 is caused by activation of the classical pathway by immune complex formation, and C3 GN results from abnormalities in the alternative pathway of complement. In previously reported cases of MPGN and C3 GN secondary to monoclonal gammopathy/multiple myeloma, renal outcome has been poor.

[Immunoglobulin G4-related disease is a newly recognized inflammatory disease].

IgG4-related disease is a newly recognized inflammatory disease characterized by tissue infiltrates of IgG4 positive plasma cells. The disease was first recognized in pancreas but has now been described in nearly every organ. The diagnosis is based on the presence of dense lymphoplasmocytic infiltrates rich in IgG4 positive plasma cells.

B-cell depletion in the treatment of lupus nephritis.

Systemic lupus erythematosus (SLE) is a systemic autoimmune disease that is clinically heterogeneous and affects multiple organs. Lupus nephritis is the most frequent severe manifestation of SLE. Conventional immunosuppressive therapy has increased the life expectancy of patients diagnosed with lupus nephritis, but only 70-80% of patients respond to this treatment and its adverse effects are considerable.

Early plasma exchange improves outcome in PR3-ANCA-positive renal vasculitis.

Objectives: Plasma exchange (PE) has been shown to improve renal outcome in anti-neutrophil cytoplasm antibody (ANCA)-associated vasculitis (AAV) and severe renal failure; however the effect of PE in AAV with moderate renal impairment is controversial.

Methods: A single-centre, retrospective one-year follow-up study, including patients with renal AAV and eGFR <60 ml/min/1.73 m2.

T cell-mediated autoimmune disease due to low-affinity crossreactivity to common microbial peptides.

Environmental factors account for 75% of the risk of developing multiple sclerosis (MS). Numerous infections have been suspected as environmental disease triggers, but none of them has consistently been incriminated, and it is unclear how so many different infections may play a role. We show that a microbial peptide, common to several major classes of bacteria, can induce MS-like disease in humanized mice by crossreacting with a T cell receptor (TCR) that also recognizes a peptide from myelin basic protein, a candidate MS autoantigen.

Functional epistasis on a common MHC haplotype associated with multiple sclerosis.

Genes in the major histocompatibility complex (MHC) encode proteins important in activating antigen-specific immune responses. Alleles at adjacent MHC loci are often in strong linkage disequilibrium; however, little is known about the mechanisms responsible for this linkage disequilibrium. Here we report that the human MHC HLA-DR2 haplotype, which predisposes to multiple sclerosis, shows more extensive linkage disequilibrium than other common caucasian HLA haplotypes in the DR region and thus seems likely to have been maintained through positive selection.

Acetaminophen-induced toxic epidermal necrolysis in a child.

Toxic epidermal necrolysis (TEN) is a severe, life-threatening disorder that usually affects adults. It is often drug induced. We report an instance of a severe case of TEN in a 6-year-old boy, probably induced by acetaminophen, and less likely by codeine.