Extracellular vesicle features are associated with COVID-19 severity.

COVID-19 is heterogeneous; therefore, it is crucial to identify early biomarkers for adverse outcomes. Extracellular vesicles (EV) are involved in the pathophysiology of COVID-19 and have both negative and positive effects. The objective of this study was to identify the potential role of EV in the prognostic stratification of COVID-19 patients. A total of 146 patients with severe or critical COVID-19 were enrolled. Demographic and comorbidity characteristics were collected, together with routine haematology, blood chemistry and lymphocyte subpopulation data. Flow cytometric characterization of the dimensional and antigenic properties of COVID-19 patients' plasma EVs was conducted. Elastic net logistic regression with cross-validation was employed to identify the best model for classifying critically ill patients. Features of smaller EVs (i.e. the fraction of EVs smaller than 200 nm expressing either cluster of differentiation [CD] 31, CD 140b or CD 42b), albuminemia and the percentage of monocytes expressing human leukocyte antigen DR (HLA-DR) were associated with a better outcome. Conversely, the proportion of larger EVs expressing N-cadherin, CD 34, CD 56, CD31 or CD 45, interleukin 6, red cell width distribution (RDW), N-terminal pro-brain natriuretic peptide (NT-proBNP), age, procalcitonin, Charlson Comorbidity Index and pro-adrenomedullin were associated with disease severity. Therefore, the simultaneous assessment of EV dimensions and their antigenic properties complements laboratory workup and helps in patient stratification.

Identification of COVID-19 patients at risk of hospital admission and mortality: a European multicentre retrospective analysis of mid-regional pro-adrenomedullin.

BACKGROUND: Mid-Regional pro-Adrenomedullin (MR-proADM) is an inflammatory biomarker that improves the prognostic assessment of patients with sepsis, septic shock and organ failure. Previous studies of MR-proADM have primarily focussed on bacterial infections. A limited number of small and monocentric studies have examined MR-proADM as a prognostic factor in patients infected with SARS-CoV-2, however there is need for multicenter validation. An evaluation of its utility in predicting need for hospitalisation in viral infections was also performed. METHODS: An observational retrospective analysis of 1861 patients, with SARS-CoV-2 confirmed by RT-qPCR, from 10 hospitals across Europe was performed. Biomarkers, taken upon presentation to Emergency Departments (ED), clinical scores, patient demographics and outcomes were collected. Multiclass random forest classifier models were generated as well as calculation of area under the curve analysis. The primary endpoint was hospital admission with and without death. RESULTS: Patients suitable for safe discharge from Emergency Departments could be identified through an MR-proADM value of ≤ 1.02 nmol/L in combination with a CRP (C-Reactive Protein) of ≤ 20.2 mg/L and age ≤ 64, or in combination with a SOFA (Sequential Organ Failure Assessment) score < 2 if MR-proADM was ≤ 0.83 nmol/L regardless of age. Those at an increased risk of mortality could be identified upon presentation to secondary care with an MR-proADM value of > 0.85 nmol/L, in combination with a SOFA score ≥ 2 and LDH > 720 U/L, or in combination with a CRP > 29.26 mg/L and age ≤ 64, when MR-proADM was > 1.02 nmol/L. CONCLUSIONS: This international study suggests that for patients presenting to the ED with confirmed SARS-CoV-2 infection, MR-proADM in combination with age and CRP or with the patient's SOFA score could identify patients at low risk where outpatient treatment may be safe.

Indication of CPAP without a sleep study in patients with high pretest probability of obstructive sleep apnea.

OBJECTIVE: To evaluate the performance of clinical criteria (CC) for diagnosis and initiation of empirical treatment with continuous positive airway pressure (CPAP) in patients with suspected obstructive sleep apnea (OSA) compared with the treatment decision based on sleep studies (polysomnography or respiratory polygraphy), guidelines, and experience of participating physicians. METHODS: This was a simulated intention-to-treat study in a retrospective (G1) and prospective (G2) cohort. Four observers (two per group) called CC1 and CC2 reviewed the sleep questionnaires and indicated CPAP if the patients presented snoring, frequent apneas (≥ 3-4/week), body mass index (BMI) > 25 kg/m2, sleepiness (Epworth > 11), or tiredness (at least 3-4 times per week) and some comorbidity (hypertension, coronary/cerebrovascular event, diabetes). Ten independent observers formed two groups of five (FD1 and FD2) and were blinded to each other's opinion. These observers in FD1 and FD2 decided CPAP treatment based on guidelines of the Spanish Society of Pulmonology and Thoracic Surgery (SEPAR) or guidelines of the American Academy of Sleep Medicine (AASM) and factored in their own opinion. Sensitivity (S), specificity (Sp), and positive/negative likelihood ratios (LR+/-) were calculated with the test method: CC1/2, and the reference method: majority decision of FD1/2. RESULTS: A total of 653 patients (264 women, 40%) were studied. Median age was 54 years, BMI 28 kg/m2, and apnea hypopnea index (AHI) 16.5 events/h. S ranged from 21 to 25% (p 0.60), Sp 96.1 to 97.6% (p 0.39), and LR+ of clinical criteria 6.4 to 8.9 (p 0.52). CONCLUSION: CPAP indication without a previous sleep study showed a low sensitivity (≅ 22%) but a specificity greater than 95% in patients with high pretest probability for OSA (snoring, report of frequent apneas, BMI > 25 kg/m2 and sleepiness or tiredness plus comorbidity).

Autoimmune thyroid disease in Libyan children and young adults with type 1 diabetes mellitus.

UNLABELLED: Diabetes mellitus is a common autoimmune endocrine disorder associated with organ-specific autoantibodies which are frequently detected at the time of diagnosis. Some of these antibodies are specific to the pancreas (GAD, IA2, ICA) while others are related to different autoimmune diseases. AIM OF THE STUDY: To define the prevalence of thyroid autoimmune disease in Libyan patients with type 1 diabetes mellitus (T1DM) since no similar studies have been performed in Libya. MATERIALS AND METHODS: Blood samples were collected from 218 patients with T1DM who are followed by the Pediatric Department, Tripoli Medical Center, Libya. All sera were analyzed in Italy (Laboratory of Immunopathology and Allergy, Udine). The patients were composed of 123 females (56.4%) and 95 males (43.6%), mean age 12.2 ± 4.6 years (range 2.1-24.5 years), mean duration of diabetes 4.7 ± 4.0 years (range 0.1-17.5 years). Sera were tested for anti-thyroperoxidase (TPO) and anti-thyroglobulin antibodies (TG). TSH and FT4 concentrations were measured in all subjects. GAD, IA-2 was also measured. RESULTS: Of the diabetic children, 23.4% were positive for anti-microsomal peroxidase antibodies (TPO-Ab) and 7.8% for antithyroglobulin antibodies (TG-Ab); whereas 6.9% of the patients were positive for both TPO-Ab and TG-Ab. Of the T1DM patients who were positive for TPO-Ab, 66.6% were females. The majority (57%) of the patients who were positive for TPO had diabetes for longer than 5 years. Five patients (2.3%) had evidence of subclinical hypothyroidism whereas two patients (0.9%) had overt hypothyroidism. Two patients had subclinical hyperthyroidism and two (0.9%) had overt hyperthyroidism. Interestingly, 16.2% of patients were positive for both thyroid and pancreatic antibodies. CONCLUSIONS: The prevalence of autoimmune thyroid disease in type 1 diabetic patients is higher than in the general population. A routine screening strategy should be implemented with the determination of anti-thyroid antibodies and TSH in type 1 diabetic patients, particularly in girls, and in patients with diabetes of more than 5 years duration. Patients who have positive TPO antibodies may need the assessment of thyroid function at shorter intervals.

MR-proADM as prognostic factor of outcome in COVID-19 patients.

Mid Regional pro-ADM (MR-proADM) is a promising novel biomarker in the evaluation of deteriorating patients and an emergent prognosis factor in patients with sepsis, septic shock and organ failure. It can be induced by bacteria, fungi or viruses. We hypothesized that the assessment of MR-proADM, with or without other inflammatory cytokines, as part of a clinical assessment of COVID-19 patients at hospital admission, may assist in identifying those likely to develop severe disease. A pragmatic retrospective analysis was performed on a complete data set from 111 patients admitted to Udine University Hospital, in northern Italy, from 25th March to 15th May 2020, affected by SARS-CoV-2 pneumonia. Clinical scoring systems (SOFA score, WHO disease severity class, SIMEU clinical phenotype), cytokines (IL-6, IL-1b, IL-8, TNF-α), and MR-proADM were measured. Demographic, clinical and outcome data were collected for analysis. At multivariate analysis, high MR-proADM levels were significantly associated with negative outcome (death or orotracheal intubation, IOT), with an odds ratio of 4.284 [1.893-11.413], together with increased neutrophil count (OR = 1.029 [1.011-1.049]) and WHO disease severity class (OR = 7.632 [5.871-19.496]). AUROC analysis showed a good discriminative performance of MR-proADM (AUROC: 0.849 [95% Cl 0.771-0.730]; p < 0.0001). The optimal value of MR-proADM to discriminate combined event of death or IOT is 0.895 nmol/l, with a sensitivity of 0.857 [95% Cl 0.728-0.987] and a specificity of 0.687 [95% Cl 0.587-0.787]. This study shows an association between MR-proADM levels and the severity of COVID-19. The assessment of MR-proADM combined with clinical scoring systems could be of great value in triaging, evaluating possible escalation of therapies, and admission avoidance or inclusion into trials. Larger prospective and controlled studies are needed to confirm these findings.

Diagnostic efficacy of the ELISA test for the detection of deamidated anti-gliadin peptide antibodies in the diagnosis and monitoring of celiac disease.

BACKGROUND AND AIM: We evaluated the diagnostic performance of an ELISA test for anti-gliadin IgA and IgG antibodies, which uses synthetic deamidated gliadin peptides (anti-gliadin antibodies, AGAs) as coating; the results were compared with a test that uses extracted gliadin (AGAe). METHODS: The study was conducted on the sera of 144 patients suffering from celiac disease (CD), including 20 patients with IgA deficiency and 9 who were following a gluten-free diet (GFD), and 129 controls. RESULTS: In the 115 CD patients (without IgA deficiency), the sensitivity of AGAe IgA and IgG was 32.2 and 60.9%, whereas that of AGAs IgA and IgG was 59.1 and 72.2%. The specificity for AGAe IgA and IgG, and AGAs IgA and IgG was 93.8 and 89.9%, and 96.9% and 99.2%, respectively. Of the 20 patients with CD and IgA deficiency, 7 tested positive for AGAe IgG and 14 for AGAs IgG. The test using deamidated gliadin peptides performed better in terms of sensitivity and specificity than the AGA tests with extracted antigen. CONCLUSIONS: The very high specificity of the AGAs IgG test (99.2%) also suggests that patients who test positive with this assay require a thorough followup, even if the anti-tissue transglutaminase antibodies (anti-tTG) and anti-endomysial autoantibodies (EMA) assays are negative.

CPAP indication based on clinical data and oximetry for patients with suspicion of obstructive sleep apnea: A multicenter trial.

BACKGROUND AND OBJECTIVE: The usefulness of pulse oximetry for the management of obstructive sleep apnea is controversial. The aim of this study was to assess the accuracy for indication of Continuous Positive Airway Pressure (CPAP) treatment in patients with suspected obstructive sleep apnea (OSA) based on clinical and oximetry data as compared to polysomnography (PSG). METHODS: This multicenter observational study involved seven sleep laboratories. Patients with suspicion of OSA who completed a standardized sleep questionnaire and a diagnostic PSG were enrolled. Eight observers logged on to a website independently and blindly. Seven observers only accessed the clinical data, curve and pulse oximetry results (Os-SO2-test method), while the eighth observer had full access to all indicators of PSG (O-PSG-reference method). Once observers assessed the information available on the website, they had to choose between three CPAP treatment options (yes/no/do not know) based on their knowledge and criteria. RESULTS: 411 subjects (228 men), median age 54 years, were available for evaluation. Os-SO2 had lower sensitivity (S), greater specificity (Sp) and positive likelihood ratio (PLR) to prescribe CPAP in patients more symptomatic (Epworth Sleepiness Scale-ESS > 10 or comorbidities) than those with fewer symptoms (ESS < 11 without comorbidities) (S 45-75% versus 45-91%, p 0.028); Sp 93.8-100% versus 68.5-96.6%, p 0.004; PLR > 10 versus 2.9-17, p<0.01). CONCLUSIONS: Due to its low false positive rate, a strategy based on pulse oximetry and clinical data was a consistent tool to indicate CPAP treatment in most symptomatic patients with a suspicion of OSA.

Interpretative comments on autoantibody tests.

Immunology laboratories perform diagnostic tests to identify the autoantibody markers needed to classify disorders which are complex, often rare, and hard to define. The recent introduction of new markers and the use of increasingly complicated assay procedures can cause difficulty in interpreting test results. Moreover, during the performance of some tests, some autoantibodies which were not requested, and consequently not expected, may be identified by chance. It is advisable for these positive results to be reported only when they have a high predictive value and suggest the possible presence of an autoimmune disease. An interpretative comment on autoantibody test results is crucial in a number of cases: when autoantibodies with a significant clinical correlation (high specificity) are found; when two or more methods are used to determine the same autoantibody and the results disagree; when unexpected autoantibody positivity is found and in case of results generated by further diagnostic tests conducted by the laboratory on its own initiative. The interpretative comment should be based on the patient's personal characteristics (sex, age) and the other laboratory parameters available; it should specify the diagnostic accuracy of the assay methods used, the clinical and diagnostic correlations of the antibodies which tested positive, and any further tests needed to complete the diagnostic process.

Antibodies to the lens and cornea in anti-DFS70-positive subjects.

Autoantibodies against DFS70 (dense fine speckles 70) antigen have recently been identified among antinuclear antibodies (ANA) in patients with various inflammatory diseases and in patients with different types of cancer. These antibodies are recognized using indirect immunofluorescence (IIF) on HEp-2 cells, by a fine speckled nuclear staining in interphase HEp-2 cells and a positive reaction in the chromosome region of mitotic cells. Given that the DFS70 protein is also known as the lens epithelium-derived growth factor, this study was performed with two objectives: (a) to assess the prevalence of these antibodies in patients sent for ANA testing and in 334 patients with different types of neoplasia and (b) to determine whether the lens tissue was a suitable substrate for the detection of antibodies specific to lens proteins. During routine workup for ANA detection by the IIF method, we found 172 DFS70-positive sera among 21,516 consecutive samples (prevalence, 0.8%). In the group of patients with neoplastic disease, 6 of 334 (1.8%) were anti-DFS70-positive. DFS70-positive sera were then assayed by the IIF method on cryostatic sections of mouse eye at a dilution of 1:40 with an anti-human IgG conjugate. Among the 172 DFS70-positive samples detected by the ANA screening, 32 (19%) were strongly reactive against the reticular fibers of the lens; 8 (5%) were positive only to the corneal epithelium (nuclear negative); 5 (3%) were positive both for the cornea and the lens fibers; 13 (7%) stained only the nuclei of lens and cornea cells, and 4 (2%) were positive against the ciliary muscle. Among the patients with neoplastic diseases, only one with lung cancer reacted weakly with the reticular fibers of the lens. Sera from 20 healthy blood donors were negative. In this preliminary study, we have shown that the prevalence of anti-DFS70 antibodies is much lower than previously reported, both in patients screened for ANA and in patients with cancer. We have also seen that some DFS70-positive sera have antibodies that recognize antigens of the lens. Further studies are needed to investigate the fine specificity and the possible significance of these new autoantibodies.

The ANA-reflex test as a model for improving clinical appropriateness in autoimmune diagnostics.

Reflex tests are widely used in clinical laboratories, for example, to diagnose thyroid disorders or in the follow-up of prostate cancer. Reflex tests for antinuclear antibodies (ANA) have recently gained attention as a way to improve appropriateness in the immunological diagnosis of autoimmune rheumatic diseases and avoid waste of resources. However, the ANA-reflex test is not as simple as other consolidated reflex tests (the TSH-reflex tests or the PSA-reflex tests) because of the intrinsic complexity of the ANA test performed by the indirect immunofluorescence method on cellular substrates. The wide heterogeneity of the ANA patterns, which need correct interpretation, and the subsequent choice of the most appropriate confirmatory test (ANA subserology), which depend on the pattern feature and on clinical information, hinder any informatics automation, and require the pathologist's intervention. In this review, the Study Group on Autoimmune Diseases of the Italian Society of Clinical Pathology and Laboratory Medicine provides some indications on the configuration of the ANA-reflex test, using two different approaches depending on whether clinical information is available or not. We further give some suggestions on how to report results of the ANA-reflex test.

Diagnostic accuracy of ELISA methods as an alternative screening test to indirect immunofluorescence for the detection of antinuclear antibodies. Evaluation of five commercial kits.

Detection of antinuclear antibodies (ANA) is a fundamental laboratory test for diagnosing systemic autoimmune diseases. Currently, the method of choice is indirect immunofluorescence (IIF) on a HEp-2 cell substrate. The goal of this study was to evaluate the diagnostic accuracy of five commercially available enzyme immunoassay (EIA) kits for ANA detection and to verify the possibility of using them as an alternative to the IIF method. The study involved 1513 patients, 315 of whom were diagnosed with a systemic autoimmune disease and 1198 in whom an autoimmune disorder was excluded. For all sera, ANA detection was performed via IIF and with five different EIA kits. The results were evaluated in relation to clinical diagnosis and the presence of possible specific autoantibodies (anti-ENA or anti-dsDNA); lastly, they were compared with the results obtained using ANA-IIF as the method of reference. The positive rate of the ANA-IIF test in subjects with systemic autoimmune diseases was 92%, whereas in the five ANA-EIA kits there was broad diversity in terms of response, with positive rates ranging from 74 to 94%. All the EIA kits correctly detected the presence of antibodies (anti-dsDNA, anti-RNP, anti-Ro/SSA) responsible for homogeneous and speckled fluorescence pattern, but at the same time they showed substantial inaccuracy with the nucleolar pattern, with a mean sensitivity of approximately 50% in this case. Instead, there was a large kit-to-kit difference in terms of identification of anti-Scl70 and centromere patterns, for which sensitivities ranged between 45 and 91%, and between 49 and 100%, respectively. The results of the study demonstrate that the commercially available ANA-EIA kits show different levels of sensitivity and specificity. Some of them have a diagnostic accuracy that is comparable and, in some cases, even higher than the IIF method. Consequently, these could be used as an alternative screening test to IIE. However, others do not ensure acceptable results. Therefore, careful evaluation of the various kits on the market is advisable before including any of these methods in the clinical and diagnostic testing.

Tratamiento con presión positiva de la Apnea Obstructiva del Sueño. Posición de la Asociación Argentina de Medicina Respiratoria / Treatment of Obstructive Sleep Apnea with Positive Pressure. Position of the Argentinian Association of Respiratory Medicine

La Sección de Sueño, Oxigenoterapia y Otros Tratamientos Crónicos Domiciliarios, de la Asociación Argentina de Medicina Respiratoria (AAMR) se planteó desarrollar en nuestro país un documento formal que exponga la base científica y costo económica de la cobertura del tratamiento del síndrome de apneas e hipopneas obstructivas durante el sueño (SAHOS). Esta iniciativa se basó en la necesidad de analizar la visión de expertos locales que se desempeñan en la realidad coyuntural cotidiana de nuestro país, para elaborar un documento informativo para miembros del equipo de salud. A su vez, exhorta a los diferentes actores del sistema a determinar pautas claras que sirvan de referencia para la generación de políticas públicas. La agenda se inició en septiembre de 2018 en un grupo de redacción. Luego, revisores de cinco provincias argentinas efectuaron una extensa valoración de la evidencia publicada. Para la edición final se realizó una reunión presencial de discusión y generación de consenso. Se plantearon como objetivos; actualizar la base científica que define al SAHOS como problema de salud de proporciones epidémicas con consecuencias demostrables en la salud, analizar los datos de costo-efectividad del tratamiento con CPAP para las formas moderadas a severas y leves con síntomas y unificar conceptos en relación con la calidad mínima necesaria en los tratamientos que se ofrecen. Finalmente, se analiza la situación en la Argentina sobre la base a datos publicados y se presenta una propuesta de mejora en tres niveles: social y económico, logístico-administrativo y clínico

The Sleep, Oxygen Therapy and Other Home Chronic Treatments Section of the Argentinian Association of Respiratory Medicine (AAMR, for its acronym in Spanish) proposed the development in our country of a formal document exposing the scientific and cost-economical foundation of the coverage for the treatment of obstructive sleep apnea and hypopnea syndrome (OSAHS). This initiative was based on the need to analyze the vision of local experts who work in the daily current reality of our country, in order to create an informative document for the members of the medical staff. In turn, it encourages the different members of the system to determine clear guidelines that could be used as reference for generating public policies. The agenda began in September, 2018 within a writing staff. Then, editors from five Argentinian provinces made a thorough assessment of published evidence. For the final edition, a face-to-face meeting was arranged to discuss and reach a consensus. The suggested objectives were: to update the scientific base that defines the OSAHS as a health problem of epidemic proportions with health consequences; to analyze cost-efficacy data of CPAP treatment for moderate to severe and mild-with-symptoms forms of the disease and to unify concepts in relation to the minimum necessary quality of treatments to be offered. Finally, the situation in Argentina is analyzed basing on published data, and a proposal is presented for improvement in three levels: social and economic, logistic-administrative and clinical.

HLA-DQ types of celiac disease in Libyan children with type 1 diabetes mellitus.

OBJECTIVE: To determine the genetic profile of celiac disease (CD) in Libyan children with type 1 diabetes as there are no data on the frequency of human leukocyte antigen (HLA)-related CD-predisposing genes in diabetic patients in Libya. METHODS: We randomly studied 218 Libyan type 1 diabetic children. The mean age was 12.2±4.6 years; 56% were female patients. The mean duration of diabetes was 4.7±4.0 years. All patients were screened for CD with IgA tissue-transglutaminase (tTG) and endomysium antibodies. Patients with positive immunological screen were programmed for a small-bowel biopsy. HLA-DRB1* and HLA-DQB1* were genotyped in all tTG-positive patients. RESULTS: Twenty-seven (12.4%) out of 218 patients with type1 diabetes had positive tTG, and 20 (9.2%) of these patients were positive for endomysium antibodies. Five patients (5/27) were already known cases of biopsy-proven CD. Biopsy was not performed in two patients. One biopsy result was normal, whereas 19 biopsies demonstrated morphological changes consistent with CD. Forty-eight percent of the anti-tTG-positive group were homozygous for HLA-DQ2, whereas 75% of biopsy-proven CD patients had HLA-DQ2, 21% had HLA-DQ2/DQ8, and 4% had HLA-DQ8. In addition, the majority (70%) carried HLA-DQ2 linkage with HLA-DRB1*03. CONCLUSION: Overall, biopsy-confirmed prevalence of CD was 11% (24 of 218). The present study confirms that CD in the Libyan type 1 diabetic population is high when compared with European and US studies, and for the first time we document that this population shares similar HLA-DQ2 genotype. This supports the theory regarding the role of the environment as an important factor in CD development in this part of the world.

Diagnostic value of faecal calprotectin in unselected outpatients referred for colonoscopy: A multicenter prospective study.

OBJECTIVES: To evaluate the role of faecal calprotectin in consecutive outpatients referred for colonoscopy. METHODS: Outpatients undergoing colonoscopy at five participating institutions were eligible. Demographic and clinical data were collected. Faecal samples were tested at a single laboratory by means of a commercially available kit. RESULTS: We consecutively enrolled 870 patients. Mean levels of calprotectin were significantly higher in patients with neoplastic and inflammatory disorders when compared with subjects with a normal colonoscopy or trivial endoscopic findings. Elevated calprotectin levels (>50mg/dl) were detected in 85% of patients with colorectal cancer, and 81% of those with inflammatory conditions but also in 37% of patients with normal or trivial endoscopic findings. In patients referred for chronic diarrhoea, sensitivity and negative predictive value were 100% in detecting either any organic colonic disease. In patients referred for symptoms of "suspected functional origin" sensitivity and negative predictive value for colorectal cancer were also 100%. CONCLUSIONS: In unselected outpatients referred for colonoscopy, a single measurement of faecal calprotectin is not sufficiently accurate to identify those with significant colorectal disease. However, a normal result can help rule out organic disease among patients with diarrhoea and those with abdominal pain and/or constipation.

Serum levels of anti-CCP antibodies, anti-MCV antibodies and RF IgA in the follow-up of patients with rheumatoid arthritis treated with rituximab.

Rheumatoid arthritis (RA) is characterized by the presence of circulating rheumatoid factor (RF) and anticitrullinated peptide antibodies (ACPA), which are positive in about 70-80% of patients. APCA have a higher specificity and therefore a higher diagnostic power than RF, but are less informative than RF in monitoring the course of the disease in patients under treatment. Recently, it has been reported that the anticitrullinated vimentin (a-MCV) antibody test can identify a particular subgroup of APCA that may be negative for anticyclic citrullinated peptide (a-CCP) antibodies. Concerning RF, the RF IgA isotype has been described as a more specific marker of erosive joint damage than total RF. The aim of our study was to monitor the levels of a-CCP, a-MCV, total RF and RF IgA in the follow-up of patients with RA treated with B-lymphocytedepletive rituximab (RTX), to detect any differences or peculiarities in patterns of these autoantibodies, especially in relation to their potential use as predictive markers of therapeutic response. We studied 30 patients with RA treated with RTX. All patients were previously unresponsive to at least 6 months of therapy with disease-modifying antirheumatic drugs (DMARDs; methotrexate, leflunomide, cyclosporine, chloroquine) and/or at least 6 months of therapy with anti-TNF biologics. The evaluation of response to RTX was made at month +6 using the EULAR criteria (DAS28). a-CCP, a-MCV, total RF and RF IgA were determined at baseline (before the first infusion of RTX) and after 1, 3 and 6 months. In serum samples obtained before treatment two cytokines essential for Blymphocyte proliferation, interleukin 6 (IL-6) and B-lymphocyte stimulator (BLyS) were also determined. In all patients a significant and consistent reduction in all the tested antibodies was found during follow-up, with no differences in respect of the degree of response to RTX. Of note, at baseline, generally a higher titre of all autoantibodies was seen in patients who then showed a better response to RTX. Finally, there were no differences in serum concentrations of IL-6 and BLyS in patients in relation to the presence or absence of the autoantibodies investigated, nor was there any significant correlation between the serum concentrations of the cytokines and the titres of the autoantibodies. Thus, neither a-MCV compared to a- CCP, nor RF IgA compared to routine total RF, provided any additional predictive information in the follow-up of patients with RA treated with RTX.

B-lymphocyte stimulator and a proliferation-inducing ligand serum levels in IgA-deficient patients with and without celiac disease.

IgA deficiency (IgAD) is the most common form of immunodeficiency and frequently associates with autoimmunity, especially with celiac disease (CD). The mechanisms underlying IgAD and the development of autoimmunity are still relatively unknown. Elevated B-lymphocyte stimulator (BLyS) and APRIL (a proliferation-inducing ligand) serum levels characterize several autoimmune diseases. We herein investigated BLyS and APRIL serum levels in IgAD patients with and without CD and compared these patients to CD patients with normal IgA and control patients (HBDs). Compared to HBDs, IgAD patients demonstrated a significant increase of BLyS (P < 0.0001) and APRIL (P = 0.003) levels, and no differences were seen between patients with or without CD. While BLyS appeared similarly overexpressed in IgAD and CD patients, APRIL was significantly increased only in IgAD patients. Because APRIL promotes IgA production, its overexpression may represent a physiological mechanism of compensation. BLyS upregulation may be involved in the increased risk of autoimmune disease development characterizing people carrying IgAD.

Cell lines that express membrane-associated DNA for anti-DNA antibody detection.

BACKGROUND: In this study, we evaluated the analytical reliability and clinical sensitivity of two tests (indirect immunofluorescence and ELISA) for anti-DNA antibodies which use cell membrane DNA (cmDNA) as antigen (Wil2 NS lymphoblastoid B cell line). METHODS: We tested 97 sera of patients with systemic lupus erythematosus (SLE) and 140 control sera from healthy subjects or from patients with other systemic autoimmune diseases or infectious diseases. The results obtained with the two anti-cmDNA kits were compared with those obtained with three other methods: indirect immunofluorescence on Crithidia luciliae, ELISA anti-double-stranded DNA (anti-dsDNA) and ELISA anti-nucleosome. RESULTS: The diagnostic sensitivity was 85% for immunofluorescence cmDNA and 90% for ELISA cmDNA, i.e., much higher than that of Crithidia (51%) and ELISA dsDNA (71%) methods, and the same as that of the ELISA nucleosome test (85%). The specificity of the cmDNA tests proved lower (92% for immunofluorescence and 87% for ELISA) than that found by anti-dsDNA Crithidia (99%), ELISA (99%) and anti-nucleosome tests (100%). CONCLUSIONS: The results of our study indicate that cmDNA tests may be used as screening tests in patients with suspected SLE. The anti-nucleosome test offers the best diagnostic accuracy overall and can play an important role in the serological diagnosis of SLE.

Frecuencia de trastornos respiratorios del sueño en pacientes con enfermedad difusa del parénquima pulmonar / Frecuency of sleep related disorders in patients with diffuse lung diseases

Introducción: Los pacientes con enfermedad pulmonar difusa (EPD) a menudo presentan fragmentación del sueño con microdespertares frecuentes. En este grupo de pacientes, la desaturación nocturna de oxígeno es frecuente con una prevalencia de 50- 80%. Se agrava en el sueño REM y se asocia con una menor calidad de vida, pudiendo contribuir al daño vascular a largo plazo. La presencia de apneas obstructivas del sueño (AOS) se presenta en el 20% de la población adulta general. Objetivos: Describir las características de los parámetros respiratorios clínicos y fisiológicos y la frecuencia de los trastornos respiratorios del sueño (TRS), especialmente de AOS, en pacientes con EPD. Materiales y métodos: Se incluyeron prospectivamente pacientes con diagnóstico establecido de EPD que consultaron en un hospital especializado en enfermedades respiratorias entre julio de 2010 y enero de 2012. Se les realizó polisomnografía (PSG) y estudio de función pulmonar (CVF y DLCO). Resultados: Se estudiaron 41 pacientes con edad promedio de 61.5 ± 12.6 años. El 54% eran hombres (n = 22). Los diagnósticos de EPD fueron neumonía intersticial usual (NIU) en el 70.7%, neumonía intersticial no específica (NINE) en el 14.6%, neumonitis por hipersensibilidad (NHS) en el 9.8% y proteinosis alveolar pulmonar (PAP) en el 4.8%. El índice de masa corporal (IMC) medio fue 29.4 ± 4.4 kg/m². En el 80% fue = 25 y en el 41% = 30. La CVF media fue de 2.18 ± 0.7 l y 64.8 ± 16.8 del porcentaje del predictivo. La DLCO ajustada a la Hb media fue de 10.3±3.6 ml/mmHg/min y 46.9 ± 14 del porcentaje del valor predictivo. Con respecto a la PSG, la SpO2 basal media fue de 93.9 ±3.4%, la saturación media durante el sueño fue 89.8 ±7% y en el 39% de los casos la SpO2 media era < 90%. En el 90% de los casos la SpO>2 mínima durante el sueño fue menor de 90%. El 34% de los casos presentaba CT 90 (tiempo con SpO2 < 90%) > 50%. De los 13 pacientes con SpO2 basal despierto > 95%, 3 presentaron un CT90 = 20% yv de los 27 pacientes con SpO2 basal > 92%, 10 cursaban con un CT90 = 20%.v Del total de los pacientes, el 48.8% presentaba AOS. El índice de apneas-hipoapneasv (IAH) medio fue 11.4 y el 20% de los pacientes presentó IAH = 15. Con respecto a la escala de somnolencia de Epworth (ESE), el 45% de los pacientes conv AOS presentaba una ESE = 10, que resultó significativamente mayor en comparación conv el grupo sin AOS. Del grupo de pacientes con IAH = 15, el 62.5% presentaban ESE < 10. Conclusiones: Un número importante de pacientes sin hipoxemia en reposo presentan desaturación durante el sueño. En este estudio, la frecuencia de AOS fue del 48.8%. Además, el grupo de pacientes con EPD con AOS presentó mayor compromiso oximétrico medido a través de CT90. Globalmente, el grupo de pacientes con AOS presentaba mayores valores de FVC (71.25% vs 58.67 p = 0.019).

Background: Patients with interstitial lung disease (ILD) often have sleep fragmentation with frequent arousals. In this group of patients, nocturnal oxygen desaturation is common, with a prevalence of 50-80%. It is worse in Rapid Eye Movement (REM) sleep, is associated with reduced quality of life and can contribute to long-term vascular damage. The presence of obstructive sleep apnea (OSA) occurs in 20% of the general adult population. Aims: To describe the characteristics of clinical and physiological respiratory parameters and frequency of respiratory sleep disorders (RSD), especially OSA, in patients with ILD. Materials and Methods: We prospectively included ILD patients who attended a specialized hospital between July 2010 and January 2012. Polysomnography (PSG) and study of pulmonary function: Forced Vital Capacity (FVC) and Diffusing Lung Capacity for Carbon Monoxide (DLCO) were performed. Results: We studied 41 patients with a mean age of 61.5 ± 12.6 years. 54% were male (n = 22). ILD diagnoses were usual interstitial pneumonia (UIP) in 70.7%, nonspecific interstitial pneumonia (NSIP) in 14.6%, hypersensitivity pneumonitis (HP) in 9.8% and pulmonary alveolar proteinosis (PAP) in 4.8%. The body mass index (BMI) was 29.4 ± 4.4 kg/m²; it was = 25 in 80% of patients and = 30 in 41%. The mean FVC was 2.18 ± 0.7 l and 64.8 ± 16.8 in the percentage of predictive value. The DLCO adjusted to Hb mean was 10.3 ± 3.6 ml/mmHg/min and 46.9 ± 14 in the percentage of predictive value. Regarding the PSG, the mean baseline SpO2 was 93.9 ± 3.4%, the mean saturation during sleep was 89.8 ± 7%, and the mean SpO2 was < 90% in 39% of cases. In 90% of cases the minimum SpO2 during sleep was less than 90%; 34% of patients had CT 90 (time with SpO2 < 90%) > 50%. In 13 patients with baseline SpO2 > 95%, 3 had CT90 = 20% and 10 of the 27 patients with basal SpO2 > 92%, had CT90 = 20%. Of all patients, 48.8% had OSA. The mean apnea-hypopnea index ...