Myositis autoantibodies detected by line blot immunoassay: clinical associations and correlation with antibody signal intensity.

The aim of this study is to assess the relationship between myositis specific (MSA) and myositis associated (MAA) antibodies and diagnosis (including idiopathic inflammatory myopathies [IIM] and other systemic autoimmune diseases [SAID]), and to explore the impact of antibody signal intensity in diagnostic accuracy. We retrospectively reviewed all the serum samples obtained from patients tested for MSA/MAA by line immunoassay (LIA) between 01/01/2018 and 31/12/2020 in Ramón y Cajal University Hospital (Spain). Clinical true positive (CTP) MSAs and MAAs were defined as those patients with IIM or SAID with phenotypes expected of that MSA/MAA. Patients who did not have a phenotype compatible with that antibody were classified as clinical false positive (CFP). One hundred and thirty positive samples were analysed. Forty-six patients (33.38%) were classified as IIM, forty-two (32.3%) as SAID and forty-two (32.3%) as non-IIM/SAID. Among these 130 patients, 164 MSA/MAA were detected. Eighty-five (51.8%) positive MSA/MAA were classified as CTP, and seventy-nine (48.2%) as CFP. Strongly positive antibodies were more frequently CTP (35/47, 74.5%) than weak positives (54/68, 36.8%), (p ˂ 0.001). Antibodies classified as CTP had a higher signal intensity than CFP (36.77 AU vs 20.00 AU, CI95% 7.79-22.09, p ˂ 0.001). The probability of a CFP was associated to negative ANA, low ANA titer, and multiple positive MSA/MAA (p Ë‚ 0.001). In this study, we confirmed that CFP results using LIA are frequent, and are associated with low signal intensity MSA/MAA, negative ANA, lower titer ANA, and with multiple positive samples.

Rheumatoid meningitis in a patient with overlap syndrome: The usefulness of anti-citrullinated peptide antibodies determination in CSF.

Rheumatoid meningitis (RM) is a rare complication of rheumatoid arthritis that can manifest as stroke-like episodes. We present the case of a 63-year-old woman with a past history of overlap syndrome and clinical manifestations suggestive of amyopathic dermatomyositis, rheumatoid arthritis, and systemic lupus erythematosus. She presented to the emergency department with sudden onset right-sided clumsiness and numbness, as well as a 2-week history of left hemicranial headache. Laboratory workup revealed positive serum antinuclear antibodies, anti-Ro antibodies, anti-citrullinated peptide antibodies (ACPA), and elevated rheumatoid factor. Lymphocytic pleocytosis, positive ACPA and anti-Ro antibodies with passive diffusion pattern, and negative microbiological studies were demonstrated in the CSF. Brain magnetic resonance imaging showed predominant left fronto-parieto-occipital leptomeningeal and pachimeningeal enhancement. She was diagnosed with RM and received methylprednisolone IV mg/kg once daily. Stroke-like episodes in the setting of a patient with lymphocytic pleocytosis in the cerebrospinal fluid (CSF) and meningeal enhancement should raise suspicion of RM. In this context, serum rheumatoid factor and ACPA levels should always be measured and ACPA should also be measured in CSF. To our knowledge, this is the first reported case of RM in the context of an overlap syndrome. ACPA levels in CSF could be a relevant diagnostic clue in the setting of central nervous system disturbance and overlapping autoimmune conditions that include rheumatoid arthritis. In our case, the presence of a suggestive clinical scenario of RM reinforces the probable pathogenic role of ACPA when it is present in the central nervous system, even without intrathecal synthesis evidence.

The Intracellular Intensity of CD3 on Aberrant Intraepithelial Lymphocytes Is a Prognostic Factor of the Progression to Overt Lymphoma in Refractory Celiac Disease Type II (Pre-Enteropathy-Associated T Cell Lymphoma).

BACKGROUND: Refractory celiac disease type II (RCD-II) is a very rare yet severe complication of celiac disease (CD) with a 50% rate of progression to Enteropathy-associated T-cell lymphoma (EATL). Timely diagnosis and treatment of RCD-II is of the essence and requires the identification of a population of frequently clonal, phenotypically aberrant intraepithelial lymphocytes (IELs). Flow Cytometry of intestinal IELs is the recommended method to identify the aberrant surface CD3-negative (sCD3-) intracytoplasmic CD3-positive (icCD3ε+) IELs, and a proportion of >20% is diagnostic of RCD-II. There is substantial heterogeneity in the clinical course of RCD-II, and insufficient information on prognostic factors. AIM: To establish flow cytometric predictors of the clinical evolution of RCD-II, to help guide treatment approaches. PATIENTS AND METHODS: Retrospective single-center study of clinical and immunological features of 6 RCD-II patients and a control group, both identified from a 2,000-patient cohort over 16 years. IEL subset frequencies and the intensity of staining for surface (s) and intracytoplasmic (ic) CD3ε+ on IEL subsets were quantified and correlated with the clinical outcome. RESULTS: Unexpectedly, the frequency of aberrant sCD3- icCD3ε+ cells at diagnosis did not correlate with histological or clinical affection. However, a higher intensity of icCD3ε+ staining in the aberrant IELs relative to expression on normal IELs correlated with monoclonality and with worse clinical outcomes. CONCLUSION: The ratio of icCD3ε+ on aberrant IELs vs. normal IELs appears to be a useful indicator of prognosis at the time of diagnosis, and may represent a novel tool in the follow-up of RCD-II patients after therapy.

Genetic and flow cytometry analysis of seronegative celiac disease: a cohort study.

Background: Seronegative celiac disease (CD) poses a diagnostic challenge. Aims: Characterize and identify differences between seronegative and seropositive CD. Patients and methods: Retrospective cohort study examining adult patients diagnosed with CD (1980-2017). Clinical, analytical, histological, genetic and immunophenotypic data were compiled. Seronegative CD was defined as a anti-tissue transglutaminase type 2 IgA and endomysial antibodies (EMA) negative and HLA-DQ2 and/or DQ8 positive, showing clinical signs of CD plus an abnormal duodenal biopsy, and responding to a gluten-free diet (GFD). Factors associated with seronegative CD were identified through binomial logistic regression. Results: Of 315 CD patients, 289 were seropositive (91.7%) and 26 seronegative (8.3%). Among the seronegative patients, higher prevalence was observed for autoimmune thyroiditis (26.9% vs. 9.7%, p = .016), HLA-DQ8 heterozygosity (23.1% vs. 2.5%, p ˂ .001) and Marsh I lesion (34.6% vs. 3.7%, p ˂ .001). The two groups showed similar flow cytometry-determined duodenal immunophenotypes and rates of refractory CD. Conclusions: Seronegative CD differs mostly in genetic (more HLA-DQ8) and histologic (milder atrophy) features as compared with seropositive. Intestinal intraepithelial immunophenotype by flow cytometry, similar in both modalities, is a useful tool to diagnose seronegative CD.

Linfoma T asociado a enteropatía: un reto diagnóstico / Enteropathy-associated T-cell lymphoma: a diagnostic challenge

El diagnóstico de la enfermedad celíaca resistente (ECR) se establece, tras la exclusión de otras entidades, ante la persistencia de datos clínicos de malabsorción y atrofia vellositaria durante 6-12meses a pesar de una estricta dieta sin gluten (DSG). La detección de alteraciones en la población linfocitaria intraepitelial es importante para su diagnóstico. Un subgrupo de pacientes con ECR pueden desarrollar complicaciones severas, como linfoma T asociado a enteropatía (LTAE). Presentamos el caso de un paciente con EC silente de larga evolución que finalmente derivó en LTAE y que evidencia el reto que supone para el clínico tanto el diagnóstico como el tratamiento de esta entidad (AU)

Diagnosis of refractory celiac disease (CD) is based on exclusion of other disorders, persistence of malabsorptive symptoms and villous atrophy, despite a strict gluten-free diet for at least 6-12months. Detection of alterations in the intraepithelial lymphocyte population is crucial for diagnosis. A subgroup of patients with refractory CD may develop severe complications such as enteropathy-associated T cell lymphoma (EATL). We present the case of a patient with longstanding silent CD who developed EALT, highlighting the challenge posed by the diagnosis and treatment of this entity (AU)

[Enteropathy-associated T-cell lymphoma: a diagnostic challenge]. / Linfoma T asociado a enteropatía: un reto diagnóstico.

Diagnosis of refractory celiac disease (CD) is based on exclusion of other disorders, persistence of malabsorptive symptoms and villous atrophy, despite a strict gluten-free diet for at least 6-12 months. Detection of alterations in the intraepithelial lymphocyte population is crucial for diagnosis. A subgroup of patients with refractory CD may develop severe complications such as enteropathy-associated T cell lymphoma (EATL). We present the case of a patient with longstanding silent CD who developed EALT, highlighting the challenge posed by the diagnosis and treatment of this entity.

[Adult celiac disease and intraepithelial lymphocytes. New options for diagnosis?]. / Enfermedad celíaca del adulto y linfocitos intraepiteliales. Nuevas opciones para el diagnóstico?

BACKGROUND: Permanent changes have been found in intraepithelial lymphocyte (IEL) subsets in patients with celiac disease. OBJECTIVE: The main aim of this study was to demonstrate the utility of determining CD3()/CD7(+) and T cell receptor (TCR) gamma-delta IEL subsets by flow cytometry as a diagnostic marker of adult celiac disease. PATIENTS AND METHODS: We performed a prospective study in a sample of 128 adult patients (70 with celiac disease and 58 controls). In all patients, distal duodenal biopsy was performed and IEL subsets were determined by flow cytometry. RESULTS: Patients with celiac disease showed an increase in gamma-delta IEL subsets and a decrease in CD3(-)/CD7(+) IEL subsets in comparison with the control group, independently of diet. CONCLUSIONS: The results indicate that IEL subset determination by flow cytometry could be useful to confirm diagnosis of celiac disease. IEL subsets should be investigated in diseases other than celiac disease, as well as in patients with potential or latent celiac disease.

Enfermedad celíaca del adulto y linfocitos intraepiteliales. ¿Nuevas opciones para el diagnóstico? / Adult celiac disease and intraepithelial lymphocytes. New options for diagnosis?

INTRODUCCIÓN: Se han apreciado cambios permanentes enlas subpoblaciones de linfocitos intraepiteliales (LIE) en lospacientes con enfermedad celíaca.OBJETIVO: El objetivo principal de este estudio fue demostrarla utilidad de la determinación de las subpoblaciones deLIE receptores de células T gamma-delta y CD3–/CD7+, mediantecitometría de flujo, como marcador diagnóstico de laenfermedad celíaca del adulto.PACIENTES Y MÉTODOS: Para ello, hemos realizado un estudioprospectivo sobre una muestra de 128 pacientes adultos (70con enfermedad celíaca y 58 controles). A todos ellos se lesrealizaron biopsias de duodeno distal, que fueron procesadasmediante citometría de flujo para la determinación desubpoblaciones de LIE.RESULTADOS: Según los resultados obtenidos, la muestra depacientes celíacos presenta un aumento de la subpoblaciónde LIE gamma-delta y un descenso en la subpoblación deLIE CD3–/CD7+, independientemente de la dieta realizada,cuando se comparan con el grupo control.CONCLUSIONES: Según los datos obtenidos, se puede concluirque la determinación de subpoblaciones de LIE mediante citometríade flujo podría resultar de utilidad para confirmarel diagnóstico de enfermedad celíaca. Sería necesario investigarlas subpoblaciones de linfocitos intraepiteliales en otrasenfermedades distintas de la enfermedad celíaca, así como enpacientes con enfermedad celíaca latente o potencial

BACKGROUND: Permanent changes have been found in intraepitheliallymphocyte (IEL) subsets in patients with celiacdisease.OBJECTIVE: The main aim of this study was to demonstratethe utility of determining CD3–/CD7+ and T cell receptor(TCR) gamma-delta IEL subsets by flow cytometry as adiagnostic marker of adult celiac disease.PATIENTS AND METHODS: We performed a prospective studyin a sample of 128 adult patients (70 with celiac disease and58 controls). In all patients, distal duodenal biopsy was performedand IEL subsets were determined by flow cytometry.RESULTS: Patients with celiac disease showed an increase ingamma-delta IEL subsets and a decrease in CD3–/CD7+ IELsubsets in comparison with the control group, independentlyof diet.CONCLUSIONS: The results indicate that IEL subset determinationby flow cytometry could be useful to confirm diagnosisof celiac disease. IEL subsets should be investigated in diseasesother than celiac disease, as well as in patients withpotential or latent celiac disease