The role of lung biopsy for diagnosis and prognosis of interstitial lung disease in systemic sclerosis: a systematic literature review

BACKGROUND

The prognostic and theragnostic role of histopathological subsets in systemic sclerosis interstitial lung disease (SSc-ILD) have been largely neglected due to the paucity of treatment options and the risks associated with surgical lung biopsy. The novel drugs for the treatment of ILDs and the availability of transbronchial cryobiopsy provide a new clinical scenario making lung biopsy more feasible and a pivotal guide for treatment. The aim of our study was to investigate the usefulness of lung biopsy in SSc ILD with a systematic literature review (SLR).

METHODS

PubMed, Embase and Cochrane databases were searched up to June 30, 2023. Search terms included both database-specific controlled vocabulary terms and free-text terms relating to lung biopsy and SSc-ILD diagnostic and prognosis. The SLR was conducted according to the Preferred Reporting Items for Systematic Reviews and Meta-analysis (PRISMA). Studies were selected according to the PEO (population, exposure, and outcomes) framework and Quality assessment of diagnostic accuracy studies (QUADAS) were reported.

RESULTS

We selected 14 articles (comprising 364 SSc-ILD patients). The paucity and heterogeneity of the studies prevented a systematic analysis. Diffuse cutaneous SSc was present in 30-100% of cases. Female predominance was observed in all studies (ranging from 64 to 100%). Mean age ranged from 42 to 64 years. Mean FVC was 73.98 (+/-17.3), mean DLCO was 59.49 (+/-16.1). Anti-Scl70 antibodies positivity was detected in 33% of cases (range: 0-69.6). All patients underwent surgical lung biopsies, and multiple lobes were biopsied in a minority of studies (4/14). Poor HRCT-pathologic correlation was reported with HRCT-NSIP showing histopathologic UIP in up to 1/3 of cases. Limited data suggest that SSc-UIP patients may have a worse prognosis and response to immunosuppressive treatment compared to other histopathologic patterns.

CONCLUSIONS

The data from this SLR clearly show the paucity and heterogeneity of the studies reporting lung biopsy in SSc ILD. Moreover, they highlight the need for further research to address whether the lung biopsy can be helpful to refine prognostic prediction and guide therapeutic choices.

POS0132 THE FIRST ALGORITHM TO INTEGRATE ULTRASONOGRAPHY IN THE DIAGNOSTIC PROCESS OF DIFFERENTIAL DIAGNOSIS OF INFLAMMATORY ARTHROPATHY IN CLINICAL PRACTICE: A STUDY FROM THE MSUS WORKING GROUP OF THE ITALIAN SOCIETY OF RHEUMATOLOGY

Background

Musculoskeletal ultrasonography (MSUS) is a useful tool for the diagnosis of several Rheumatic and Musculoskeletal Diseases (RMDs) but its role in the diagnostic pathways in clinical practice is still unclear as feasibility issues limit its application as a bed side technique.

Objectives

To optimize the use of US in clinical practice, the MSUS Study Group of the Italian Society for Rheumatology aimed to develop an algorithm combining US with clinical and laboratory findings to improve the differential diagnosis among patients presenting with joint swelling.

Methods

Based on a systematic literature review1 and experts’ opinion, MSUS Study Group Members attempt to identify a set of statements including the main US elementary lesions useful for US scanning in the suspicion of Rheumatoid arthritis (RA), Psoriatic arthritis (PsA), Rheumatic Polymyalgia (PMR), Gout, Calcium Pyrophosphate Deposition Disease (CPPD), Osteoarthritis (OA). Then, the MSUS Study Group defined through a survey and ranked in a 1000minds exercise the most important clinical/laboratory findings for the differential diagnosis of those diseases. Higher-ranked items were fitted in an algorithm driving the differential diagnosis of RMDs to a reduced spectrum of 2 to 4 possible diseases. Finally, the algorithm supported the performance of US according to the established scans for those specific diseases. To assess the algorithm’s performance, a pilot study was conducted on 59 patients, comparing the algorithm-based diagnosis with the final diagnosis based on rheumatologist’s experience and/or on classification criteria.

Results

Sets of elementary US lesions and a scanning protocol for each included pathology were created (Table 1), optimized towards high sensibility and specificity. Among the findings evaluated, the age (<50 / ≥50 years old), the number of the involved joints (monoarticular/polyarticular), the serology (Rheumatoid Factor [RF] and anti-citrullinated protein antibody [ACPA]); the acute-phase reactants (C-reactive protein [CRP]; erythrocyte sedimentation rate [ESR]) reached the higher ranking in the survey and were introduced in the algorithm, showed in Figure 1. In the pilot study, the algorithm-based diagnosis was consistent with the final diagnosis in 52 cases (accuracy 88.1%). Among the 7 cases in which the algorithm misclassified patients, four patients had a final diagnosis of OA (3 diagnosed by the algorithm as PMR/RA/PSA and one as PSA), one gout (algorithm diagnosis: OA/CPPD/PSA), one RA (algorithm diagnosis: Gout/CPPD/PSA) and one CPPD (algorithm diagnosis: PMR/RA/PSA).

Table 1.

Elementary ultrasound lesions and joints to be scanned for each included pathology

DiseaseSites to scanUS elementary lesionsRAII-IV MCPsSynovial Hypertrophy (SH), Power Doppler (PD), erosionsWristV MTPPsAII-III MCPsPeritendonitisPIPsEnthesitisSoft tissue oedemaFlexor tendons of the handsTenosynovitisSoft tissue oedemaAchille’s tendon enthesisPD, erosionsProximal patellar tendon enthesisCPPDKnees (menisci and Hyaline Cartilage)CPP depositsWrist (triangular fibrocartilage complex)Any involved sitesCPP deposits, SH, PDGoutKneesDouble contour, tophiI MTPInvolved sitesSHPDOAInvolved sitesOsteophytesCartilage changesPMRShouldersBursitisArthritisRotator cuff integrityFigure 1.

The final algorithm

Conclusion

The diagnostic algorithm produced in this pilot study correctly classified patients with the most prevalent RMDs in clinical practice. A longitudinal study on a large sample size is ongoing to evaluate the added value of US when implemented in this algorithm regarding diagnostic certainty, accuracy and early diagnosis.

References

[1]Sakellariou G, Scirè CA, Adinolfi A, Batticciotto A, Bortoluzzi A, Delle Sedie A, et al. Differential Diagnosis of Inflammatory Arthropathies by Musculoskeletal Ultrasonography: A Systematic Literature Review. Front Med. 7 maggio 2020;7:141.

Disclosure of Interests

None declared

POS0278 COMPARISON OF ULTRASOUND BEAM ATTENUATION BY CALCIUM PYROPHOSPHATE, HYDROXYAPATITE AND MONOSODIUM URATE CRYSTALS: A PROOF-OF-CONCEPT STUDY

Background

Ultrasound (US) demonstrated to be reliable and accurate for the diagnosis of crystal induced arthropathies, especially gout and calcium pyrophosphate deposition disease (CPPD) and validated definitions for uric acid and calcium pyrophosphate deposition in joints were released by the Outcome Measures in Rheumatology (OMERACT) US group. Less is known regarding hydroxyapatite (HA) deposition disease (HAAD) and the role of US in the assessment of HA crystal deposition.

It is general belief that HA crystals create posterior acoustic shadowing, monosodium urate could create or not US beam attenuation while CPP crystals generally do not attenuate the US beam.

Objectives

Aim of this proof-of-concept study was to investigate the US appearance in terms of beam attenuation due to increasing concentrations of MSU, CPP and HA crystals.

Methods

Sixteen synthetic crystal suspensions with known concentrations of CPP (26-109 mg/mL), HA (31-153 mg/mL) and MSU (90-500 mg/mL) were prepared. These specific concentrations were selected to replicate the X-ray attenuation characteristics of those crystals when imaged by conventional radiography, computed tomography (CT) and dual-energy CT (DECT) in vivo[1]. The density of the agar-based lipogel background was intentionally increased to mimic the X-ray attenuation of hyaline cartilage (i.e., 100-120 HU at 120 kVp). Each crystal suspension was placed in a plastic container filled with US gel, next to the control (i.e., crystal-free background) calibration phantom. We acquired all US images using a Samsung RS80A system equipped with a high-frequency linear array transducer (4-18 MHz) set at the maximum frequency, by applying the same settings. US scans were performed by a single experienced sonographer, blinded to the crystal type and concentration. For each of the 16 crystal suspensions, at least two images were recorded both in the long- and short-axis views, the latter including the control phantom in the field of view. Interpretation of US images for the extent of US beam attenuation and the presence of acoustic shadowing was performed in consensus with a second experienced sonographer.

Results

None of the five CPP phantoms generated posterior acoustic shadowing or US beam attenuation regardless of CPP concentration. HA 31mg/mL did not generate US beam attenuation, while HA 62, 92 and 123 mg/mL generated a progressively increasing US beam attenuation with posterior acoustic shadow clearly generated by HA 153 mg/mL. Similarly, MSU 90 mg/mL did not generate US beam attenuation. MSU 195 mg/mL generated only a very faint US beam attenuation that became progressively more visible at 270 and 345 mg/mL even if a clear posterior acoustic shadow was detectable only with MSU 420 and 500 mg/mL (Figure 1).

Figure 1.

Short-axis views comparing the US attenuation characteristics, including acoustic shadowing, of increasing concentrations (in mg/mL) of CPP, HA and MSU crystals. The left column shows the US attenuation of the crystal-free (0 mg/mL) agar-based lipogel background for reference

Conclusion

This proof-of-concept study confirmed that in the concentrations of crystals encountered in vivo, CPP do not generate posterior shadowing, while MSU and HA determine US beam attenuation proportionally to the concentration of the crystals. Being this a proof-of-concept study, attenuation of the US beam was assessed empirically and not in a quantitative or semi-quantitative way. However, this study highlights the potential of US to differentiate between CPP, MSU and HA crystals based on their appearance on gray scale imaging. Future studies should be carried out with different crystal concentrations, different US equipment and settings, in order to create a scoring system for US beam attenuation that is actually lacking.

References

[1]Pascart T et al. Dual-energy computed tomography in calcium pyrophosphate deposition: initial clinical experience. Osteoarthritis Cartilage 2019;27:1309–14. doi:10.1016/j.joca.2019.05.007

Disclosure of Interests

None declared

OP0168 DEVELOPMENT OF AN ULTRASOUND SCORING SYSTEM FOR CPPD EXTENT: RESULTS FROM A DELPHI PROCESS AND WEB-RELIABILITY EXERCISE BY THE OMERACT US WORKING GROUP

Background

Ultrasound (US) has proven to be an excellent imaging technique for detecting calcium pyrophosphate (CPP) deposition disease (CPPD); it is also widely available and inexpensive and can be performed during the clinic visit making it the preferred imaging modality for many rheumatologists. However, no validated grading systems have yet been developed allowing for a quantification of the extent of crystal deposition in CPPD.

Objectives

The aim of this study was to develop a scoring system for the quantification of CPP deposition at a patient level according to the OMERACT framework.

Methods

As part of the OMERACT methodology, we performed a systematic literature review (SLR) and meta-analysis aimed to estimate the prevalence of CPP deposition in peripheral joints by imaging, in order to identify relevant joints for CPPD monitoring. A preliminary survey was also circulated among the members of the OMERACT US – CPPD working group to collect their own suggestions according to their personal experience. Subsequently, a Delphi survey was prepared and circulated between members of the group, including statements that reflected both the results of the SLR and of the preliminary survey. In total, 32 statements were generated regarding the type of scoring for single structures, the sites to be included, the final scoring at patient level, and the scanning technique. Participants were asked to reply on a 5-point Likert scale (1, strongly disagree to 5, strongly agree) and agreement was achieved when 4 and 5 grades reached 75% or more of concordance. In case of disagreement, new statements were proposed according to the members’ suggestions and circulated for voting in a subsequent round. After agreement of a scoring system, the validation process began. Two rounds of a web-based exercise on static images were conducted on 120 images representing equally all sites under investigation and all degrees of crystal deposition, to assess the intra- and inter-reader reliability of the new scoring system. Representative images of the scoring system were visible throughout the entire exercise in order to facilitate the scoring of the lesions.

Results

Three Delphi rounds were needed to reach agreement on all items. 32/41 members of the OMERACT US-CPPD working group replied in the first round, 26/32 in the second, and 25/26 in the third round. Twenty statements were approved in the first round, 3 in the second, and 3 in the third round. Only the knees (menisci and hyaline cartilage) and the triangular fibrocartilage of the wrist were included in the final score, using a four-grade system (0-3). It was decided that each anatomical structure should be scored separately and then also summed in order to define the joint score. The sum of the assessed joints was the total score at patient level. The final scoring system with the definitions and the relative technical notes is represented in Figure 1. 33/41 members participated to the reliability exercise. The inter-reader reliability of the scoring was substantial (kappa of 0.72), and the intra-reader reliability was almost perfect (kappa of 0.82).

Conclusion

This is the first study for developing a scoring system for the extent of CPP crystal deposition in patients with CPPD. The scoring system demonstrated to be reliable in static images. The next step of the validation process is to assess the reliability of the scoring system in a patient-based exercise. This study represents a fundamental step in the OMERACT process of validating US as an outcome measure instrument, and above proposed scoring system will hopefully provide a useful tool for clinical practice and research.

Disclosure of Interests

None declared

Building an Artificial Intelligence Laboratory Based on Real World Data: The Experience of Gemelli Generator

The problem of transforming Real World Data into Real World Evidence is becoming increasingly important in the frameworks of Digital Health and Personalized Medicine, especially with the availability of modern algorithms of Artificial Intelligence high computing power, and large storage facilities.Even where Real World Data are well maintained in a hospital data warehouse and are made available for research purposes, many aspects need to be addressed to build an effective architecture enabling researchers to extract knowledge from data.We describe the first year of activity at Gemelli Generator RWD, the challenges we faced and the solutions we put in place to build a Real World Data laboratory at the service of patients and health researchers. Three classes of services are available today: retrospective analysis of existing patient data for descriptive and clustering purposes; automation of knowledge extraction, ranging from text mining, patient selection for trials, to generation of new research hypotheses; and finally the creation of Decision Support Systems, with the integration of data from the hospital data warehouse, apps, and Internet of Things.

POS0618 PERSISTENCE OF REMISSION AFTER TAPERING OF GOLIMUMAB IN INFLAMMATORY JOINT DISEASE (IJD)

Background:

In refractory IJD, remission may be obtained with antiTNFa drugs and other biological disease modifying anti-rheumatic drugs (bDMARDs). The last EULAR recommendations suggest tapering of bDMARD when remission persists1. However, best timing and modality of tapering are uncertain and specific knowledge on patients’ characteristics associated to a better outcome is still lacking.

Objectives:

To evaluate the persistency of remission after increasing the interval between injections of Golimumab in a group of patients affected by rheumatoid arthritis (RA), psoriatic arthritis (PsA), ankylosing spondylitis (AS) and juvenile idiopathic arthritis (JIA) and to identify any variables associated to disease flare after tapering.

Methods:

Between 2011 and July 2020, 80 patients affected by RA, PsA, AS and JIA treated with Golimumab were enrolled. Their demographic and clinical data, including inflammation (ESR and cRP) and clinimetric indices (DAS28 or BASDAI), were collected at baseline and during the follow up visit (T1). In 22/80 patients that reached clinical remission at T1, the time between Golimumab injections has been prolonged (mean time between injection: 43.7 days); ESR and cRP, DAS28/BASDAI, and time since the start of the tapering (weeks) were evaluated in the next control visit (T2).

Results:

80 patients were enrolled (32 male, mean age 50.6 years +/- 13.91), 34 AS, 33 PsA, 9 RA and 4 JIA. At baseline they have an active disease with a DAS 28 of 4.74+/-0.85 and a BASDAI of 5.23+/- 1.31. At T1, 60/80 patients were in remission (75%), with a mean DAS 28 of 1.84+/- 0.6 and an average BASDAI of 1.32+/-0.6, and 22/60 patients started drug tapering. At T2, 20/22 patients (91%) were in remission, (DAS 28 1.9+/-0.49, BASDAI of 0.8+/- 0, 67). A significantly higher BASDAI was observed at T1, even though in the range of absence of disease activity (2.2, +/- 0.28 vs 0.58, +/- 0.47; p <0.001) in patients who, after extending the therapeutic interval (T1) were no longer in remission at T2. Patients with a flare of disease activity (2/22) were taken back to the 28 days window of Golimumab with a prompt recovery of disease remission. Out of the 38 patients maintained at the standard dose, 4 experienced a disease flare with necessity to switch or swope bDMARD, with a retention rate in this group of 90%. Difference of retention rate between patients on standard vs reduced dose was not statistically significative.

Conclusion:

Tapering of Golimumab was successful in 91% of the cases without flare. Moreover, the prolongation of the increase of the treatment window provided the same result as that obtained in patients that continued in the standard time window. This evidence suggests that the extension of the gap between Golimumab administrations may be feasible and safely applied in practice.

References:

[1]Smolen JS, Landewé RBM, Bijlsma JWJ, et al EULAR recommendations for the management of rheumatoid arthritis with synthetic and biological disease-modifying antirheumatic drugs: 2019 update Annals of the Rheumatic Diseases 2020;79:685-699.

Disclosure of Interests:

None declared

Process mining to optimize palliative patient flow in a high-volume radiotherapy department

•

Management of palliative patients can be often out of standard clinical pathways.

•

Process mining methodology has still not been exploited for palliative patients.

•

Process discovery of event-log highlighted current workflow complexity/ weaknesses.

•

Conformance checking evaluated how a set of events-log flow through a given model.

•

Palliative patient patterns of care can be tracked and monitored by process mining.

Introduction

In radiotherapy, palliative patients are often suboptimal managed and patients experience long waiting times. Event-logs (recorded local files) of palliative patients, could provide a continuative decision-making system by means of shared guidelines to improve patient flow. Based on an event-log analysis, we aimed to accurately understand how to successively optimize patient flow in palliative care.

Methods

A process mining methodology was applied on palliative patient flow in a high-volume radiotherapy department. Five hundred palliative radiation treatment plans of patients with bone and brain metastases were included in the study, corresponding to 290 patients treated in our department in 2018. Event-logs and the relative attributes were extracted and organized. A process discovery algorithm was applied to describe the real process model, which produced the event-log. Finally, conformance checking was performed to analyze how the acquired event-log database works in a predefined theoretical process model.

Results

Based on the process discovery algorithm, 53 (10%) plans had a dose prescription of 8 Gy, 249 (49.8%) plans had a dose prescription of 20 Gy and 159 (31.8%) plans had a dose prescription of 30 Gy. The remaining 39 (7.8%) plans had different dose prescriptions. Considering a median value, conformance checking demonstrated that event-logs work in the theoretical model.

Conclusions

The obtained results partially validate and support the palliative patient care guideline implemented in our department. Process mining can be used to provide new insights, which facilitate the improvement of existing palliative patient care flows.

Gastrointestinal stromal tumors and second primary malignancies: a retrospective monocentric analysis

In the post-Imatinib era, the median survival of patients diagnosed with GIST has reached almost 5 years. Prolonging GIST-specific survival, GIST patients have an increased incidence of secondary neoplasia. Data on the prognostic impact of second tumors in GIST patients are very poor with few and small retrospective analyses available in the literature. We conducted a retrospective monocentric analysis on 145 patients diagnosed with GIST between April 2001 and October 2018. Kaplan-Meier and Cox hazard methods were used for survival analysis. A total of 154 GIST patients were included and 31 patients of them (21%) were diagnosed with at least one additional malignancy. The most common second tumors associated with GIST were gastrointestinal tumors. GIST patients with additional malignancies showed to have lower size (>5 cm: 35% vs 45%; p=0.75), higher mitotic rate (>5/50 HPFs: 42% vs 29%; p=0.24), higher presence of c-KIT mutation (85% vs 69%), a lower presence of PDGFRα mutation (8% vs 17%; p=0.05) and shorter survival (mOS: 9.6 vs 15.5 years; p=0.30). In conclusion, our study did not find any significant correlation between clinicopathological characteristics and the development of a second tumor in GIST patients. Further analyses and strict follow up protocols are needed in order to early diagnose and promptly treat a second primary tumor in the GIST population.

Immunoglobulin A antibodies to oxidized collagen type II as a potential biomarker for the stratification of spondyloarthritis from rheumatoid arthritis

OBJECTIVES

The discovery of diseased tissue-specific neoantigens offers the opportunity to develop important disease tissue-specific biomarkers that can help in the prediction, diagnosis, and stratification of diseases. This opportunity is specifically significant for autoimmune diseases where diagnostic biomarkers are not available. Inflammatory autoimmune diseases are commonly associated with local generation of large amounts of reactive oxidants. We have previously identified oxidative post-translationally modified (oxPTM) tissue-specific neoantigens in rheumatoid arthritis (RA) and type 1 diabetes that elicit an immune response. In the current study, we studied the presence and clinical significance of antibodies to oxPTM collagen type II (CII) in patients with spondyloarthritis (SpA).

METHOD

Levels of antibodies specific to native CII and oxPTM-CII were assessed by enzyme-linked immunosorbent assay.

RESULTS

Immunoglobulin G (IgG) binding to oxPTM-CII was observed in 52%, 83%, and 28% of serum samples from patients with axial spondyloarthritis (axSpA), RA, and psoriatic arthritis (PsA), respectively. Importantly, while strong IgA anti-oxPTM-CII responses were detected in axSpA and PsA patients, with 47% and 84% respective binders, no IgA anti-oxPTM-CII was detected in RA patients. IgA anti-oxPTM-CII reactivity in axSpA patients treated with biologics was higher and more frequent, with 85% binders compared to 9% binders in patients treated with synthetic disease-modifying anti-rheumatic drugs.

CONCLUSION

Our data imply that SpA and PsA are associated with the presence of antibodies to oxPTM-CII, suggesting that there may be a humoral component that may distinguish patients with SpA from RA. Our approach could be adapted to other diseases, particularly to inflammatory autoimmune diseases.

Oceanographic Variability induced by Tides, the Intraseasonal Cycle and Warm Subsurface Water intrusions in Maxwell Bay, King George Island (West-Antarctica)

We examine the hydrographic variability induced by tides, winds, and the advance of the austral summer, in Maxwell Bay and tributary fjords, based on two recent oceanographic campaigns. We provide the first description in this area of the intrusion of relatively warm subsurface waters, which have led elsewhere in Antarctica to ice-shelf disintegration and tidewater glacier retreat. During flood tide, meltwater was found to accumulate toward the head of Maxwell Bay, freshening and warming the upper 70 m. Below 70 m, the flood tide enhances the intrusion and mixing of relatively warm modified Upper Circumpolar Deep Water (m-UCDW). Tidal stirring progressively erodes the remnants of Winter Waters found at the bottom of Marian Cove. There is a buoyancy gain through warming and freshening as the summer advances. In Maxwell Bay, the upper 105 m were 0.79 °C warmer and 0.039 PSU fresher in February than in December, changes that cannot be explained by tidal or wind-driven processes. The episodic intrusion of m-UCDW into Maxwell Bay leads to interleaving and eventually to warming, salinification and deoxygenation between 80 and 200 m, with important implications for biological productivity and for the mass balance of tidewater glaciers in the area.

Observations and Projections of Heat Waves in South America

Although Heat Waves (HWs) are expected to increase due to global warming, they are a regional phenomenon that demands for local analyses. In this paper, we assess four HW metrics (HW duration, HW frequency, HW amplitude, and number of HWs per season) as well as the share of extremely warm days (TX95, according to the 95th percentile) in South America (SA). Our analysis included observations as well as simulations from global and regional models. In particular, Regional Climate Models (RCMs) from the Coordinated Regional Climate Downscaling Experiment (CORDEX), and Global Climate Models (GCMs) from the Coupled Model Intercomparison Project Phase 5 (CMIP5) were used to project both TX95 estimates and HW metrics according to two representative concentration pathways (RCP4.5 and RCP8.5). We found that in recent decades the share of extremely warm days has at least doubled over the period December-January-February (DJF) in northern SA; less significant increases have been observed in southern SA. We also found that by midcentury, under the RCP4.5 scenario, extremely warm DJF days (as well as the number of HWs per season) are expected to increase by 5-10 times at locations close to the Equator and in the Atacama Desert. Increases are expected to be less pronounced in southern SA. Projections under the RCP8.5 scenario are more striking, particularly in tropical areas where half or more of the days could be extremely warm by midcentury.

Improved accuracy in DFS pattern interpretation using a novel HEp-2 ELITE system

INTRODUCTION/OBJECTIVES

Accurate interpretation of DFS70 (dense fine speckled 70) and mixed antinuclear antibodies (ANAs) patterns can be challenging using conventional HEp-2 immunofluorescence (IIF) method. We evaluated a novel HEp-2 IIF substrate (HEp-2 ELITE/DFS70-KO) composed of a mixture of engineered HEp-2 devoid of the DFS70 autoantigen and conventional HEp-2 cells. The study assessed the utility of the new substrate in ANA screening and its advantages.

METHOD

One thousand and five consecutive routine samples sent for ANA screening were tested on both standard HEp-2 and the HEp-2 ELITE DFS70 KO substrates (ImmuGlo ANA HEp-2 and HEp-2 ELITE/DFS70-KO, Trinity Biotech, Buffalo, NY). Anti-DFS70 antibody specificity was additionally determined by immunoblot (IB). Clinical and serological data were included in the analysis of the overall impact of the novel HEp-2 substrate on DFS pattern interpretation.

RESULTS

Of the 22 cases suspected as positive for DFS pattern alone or in combination with homogeneous or speckled patterns on conventional HEp-2 cells, 17 were interpreted with a higher accuracy using the new HEp-2 ELITE method as positive for DFS70 (monospecific DFS70 (10), mixed DFS70 (7)), speckled (3), and DFS (2) patterns.

CONCLUSIONS

The new substrate was not only useful in deciphering unclear mixed ANA patterns but also highly sensitive in detecting DFS70 pattern in comparison to the DFS70 positivity obtained using IB.

Effects of soiling on photovoltaic (PV) modules in the Atacama Desert

Soiling by dry deposition affects the power output of photovoltaic (PV) modules, especially under dry and arid conditions that favor natural atmospheric aerosols (wind-blown dust). In this paper, we report on measurements of the soiling effect on the energy yield of grid-connected crystalline silicon PV modules deployed in five cities across a north-south transect of approximately 1300 km in the Atacama Desert ranging from latitude 18°S to latitude 30°S. Energy losses were assessed by comparing side-by-side outputs of four co-planar PV modules. Two of the PV modules of the array were kept clean as a control, while we allowed the other two to naturally accumulate soiling for 12 months (from January 2017 to January 2018). We found that the combination of high deposition rates and infrequent rainfalls led to annual energy losses that peaked at 39% in the northern coastal part of the desert. In contrast, annual energy losses of 3% or less were measured at relatively high-altitude sites and also at locations in the southern part of the desert. For comparison, soiling-induced annual energy losses of about 7% were measured in Santiago, Chile (33°S), a major city with higher rainfall frequency but where urban pollution plays a significant role.

Ultraviolet radiation in the Atacama Desert

The world's highest levels of surface ultraviolet (UV) irradiance have been measured in the Atacama Desert. This area is characterized by its high altitude, prevalent cloudless conditions, and a relatively low total ozone column. In this paper, we provide estimates of the surface UV (monthly UV index at noon and annual doses of UV-B and UV-A) for all sky conditions in the Atacama Desert. We found that the UV index at noon during the austral summer is expected to be greater than 11 in the whole desert. The annual UV-B (UV-A) doses were found to range from about 3.5 kWh/m² (130 kWh/m²) in coastal areas to 5 kWh/m² (160 kWh/m²) on the Andean plateau. Our results confirm significant interhemispherical differences. Typical annual UV-B doses in the Atacama Desert are about 40% greater than typical annual UV-B doses in northern Africa. Mostly due to seasonal changes in the ozone, the differences between the Atacama Desert and northern Africa are expected to be about 60% in the case of peak UV-B levels (i.e. the UV-B irradiances at noon close to the summer solstice in each hemisphere). Interhemispherical differences in the UV-A are significantly lower since the effect of the ozone in this part of the spectrum is minor.

Jaccoud's arthropathy, an unusual manifestation of idiopathic retroperitoneal fibrosis: rapid improvement of symptoms after tocilizumab treatment

Jaccoud's arthropathy (JA) is a chronic, non erosive, rheumatoid-like deformity associated with rheumatic fever (RF) and systemic lupus erythematosus and with other diseases such as psoriatic arthritis, connective tissue diseases, hypocomplementemic urticarial vasculitis, infections, sarcoidosis and neoplasia. We described a case of JA in a patient with cutaneous psoriasis but with a particular disease evolution associated with idiopathic retropritoneal fibrosis (IRF), evaluated with computed tomography, magnetic resonance and 18F-FDG PET/ CT. The patient, following failure with steroids, methotrexate and etanercept, was treated with tocilizumab (8 mg/kg) once every 4 weeks for 6 months. A rapid improvement of symptoms and disappearance of 18F-FDG uptake was shown. We describe a review of literature of rheumatic manifestations of IRF and the possible role of interleukin-6 in the pathway of JA and IRF.

PRODIGE: PRediction models in prOstate cancer for personalized meDIcine challenGE

AIM

Identifying the best care for a patient can be extremely challenging. To support the creation of multifactorial Decision Support Systems (DSSs), we propose an Umbrella Protocol, focusing on prostate cancer.

MATERIALS & METHODS

The PRODIGE project consisted of a workflow for standardizing data, and procedures, to create a consistent dataset useful to elaborate DSSs. Techniques from classical statistics and machine learning will be adopted. The general protocol accepted by our Ethical Committee can be downloaded from cancerdata.org .

RESULTS

A standardized knowledge sharing process has been implemented by using a semi-formal ontology for the representation of relevant clinical variables.

CONCLUSION

The development of DSSs, based on standardized knowledge, could be a tool to achieve a personalized decision-making.

The impact of biological treatments on the anti-dsDNA and anti-nucleosome tests

Background Anti-double stranded DNA antibodies are a very heterogeneous group of antibodies, quite specific for systemic lupus erythematosus. Newer technologies, such as addressable laser bead immunoassays (ALBIA), show great potential as a diagnostic application. The production of anti-double stranded DNA antibodies is often encountered in inflammatory arthritis; however, literature reports that the actual onset of drug induced lupus in patients treated with biological drugs is a rare event. False positive results for anti-double stranded DNA and anti-nucleosome antibodies detected in patients with inflammatory arthritis treated with different biologics prompted the investigation of full autoantibody profiles to evaluate each biomarker's diagnostic performance in systemic lupus erythematosus. The aim of the study was to compare the diagnostic performance of anti-double stranded DNA antibody and anti-nucleosome antibody methods and to evaluate the value of simultaneously measuring anti-double stranded DNA and anti-nucleosome antibodies, along with other anti-nuclear antibody analytes, as biomarkers for systemic lupus erythematosus, using a more appropriate control cohort including inflammatory arthritis patients with a non-clinical drug induced lupus. Methods Anti-double stranded DNA and anti-nucleosome antibody levels were evaluated in 247 patient samples: 70 systemic lupus erythematosus, 177 disease controls (including 97 inflammatory arthritis during treatment with different biologics) using the Bio-Rad BioPlex® 2200. Results Anti-nucleosome antibodies demonstrated greater clinical sensitivity and specificity than anti-double stranded DNA antibodies. At the manufacturers' cut-off range, considering the two markers as a single or combined test, the "anti-double stranded DNA test or anti-nucleosome antibodies" was the most sensitive combination (0.400) with the best negative likelihood ratio (0.62) and negative predictive value (0.803). Conclusion Anti-nucleosome antibodies are a more sensitive and specific biomarker of systemic lupus erythematosus than anti-double stranded DNA antibodies. Anti-nucleosome antibodies and anti-double stranded DNA antibodies are independent and complementary markers of systemic lupus erythematosus diagnosis and, therefore, are strongly suggested as combined tests (positive predictive value = 0.938). Moreover, the combined use of the two tests may help to overcome the decreased specificity percentage of the anti-double stranded DNA test, when considering an inflammatory arthritis cohort under biological therapies. The ALBIA method for anti-nuclear specificity detection allows a full autoantibody assessment, resulting in a much higher clinical specificity for systemic lupus erythematosus in the presence of ≥3 positive markers and significantly more positive likelihood ratio when ≥2 positive markers are present.

Aseptic HLA B27-positive spondylodiscitis: decreased 18F-FDG uptake after etanercept treatment

We observed a 69-year old man suffering from HLA B27 ankylosing spondylitis with persistent night back pain. 18F-FDG-PET/CT showed an increased metabolism at the level of the spinal space of L2-L3, L3-L4 with increased uptake compatible with spondylodiscitis. He started therapy with etanercept 50 mg/week. After six months of treatment repeated testing showed no uptake of the discs and vertebral bodies.

The Solar Spectrum in the Atacama Desert

The Atacama Desert has been pointed out as one of the places on earth where the highest surface irradiance may occur. This area is characterized by its high altitude, prevalent cloudless conditions and relatively low columns of ozone and water vapor. Aimed at the characterization of the solar spectrum in the Atacama Desert, we carried out in February-March 2015 ground-based measurements of the spectral irradiance (from the ultraviolet to the near infrared) at seven locations that ranged from the city of Antofagasta (on the southern pacific coastline) to the Chajnantor Plateau (5,100 m altitude). Our spectral measurements allowed us to retrieve the total ozone column, the precipitable water, and the aerosol properties at each location. We found that changes in these parameters, as well as the shorter optical path length at high-altitude locations, lead to significant increases in the surface irradiance with the altitude. Our measurements show that, in the range 0–5100 m altitude, surface irradiance increases with the altitude by about 27% in the infrared range, 6% in the visible range, and 20% in the ultraviolet range. Spectral measurements carried out at the Izaña Observatory (Tenerife, Spain), in Hannover (Germany) and in Santiago (Chile), were used for further comparisons.

Predictive value of the Diverticular Inflammation and Complication Assessment (DICA) endoscopic classification on the outcome of diverticular disease of the colon: An international study

BACKGROUND

Diverticular Inflammation and Complication Assessment (DICA) endoscopic classification has been recently developed for patients suffering from diverticulosis and diverticular disease.

AIMS

We assessed retrospectively the predictive value of DICA in patients for whom endoscopic data and clinical follow-up were available.

METHODS

For each patient, we recorded: age, severity of DICA, presence of abdominal pain, C-reactive protein and faecal calprotectin test (if available) at the time of diagnosis; months of follow-up; therapy taken during the follow-up to maintain remission (if any); occurrence/recurrence of diverticulitis; need of surgery.

RESULTS

We enrolled 1651 patients (793 M, 858 F, mean age 66.6 ± 11.1 years): 939 (56.9%) patients were classified as DICA 1, 501 (30.3%) patients as DICA 2 and 211 (12.8%) patients as DICA 3. The median follow-up was 24 (9-38) months. Acute diverticulitis (AD) occurred/recurred in 263 (15.9%) patients; surgery was necessary in 57 (21.7%) cases. DICA was the only factor significantly associated to the occurrence/recurrence of diverticulitis and surgery either at univariate (χ(2 )= 405.029; p < 0.0001) or multivariate analysis (hazard ratio = 4.319, 95% confidence interval (CI) 3.639-5.126; p < 0.0001). Only in DICA 2 patients was therapy effective for prevention of AD occurrence/recurrence with a hazard ratio (95% CI) of 0.598 (0.391-0.914) (p = 0.006, log rank test). Mesalazine-based therapies reduced the risk of AD occurrence/recurrence and needs of surgery with a hazard ratio (95% CI) of 0.2103 (0.122-0.364) and 0.459 (0.258-0.818), respectively.

CONCLUSIONS

DICA classification is a valid parameter to predict the risk of diverticulitis occurrence/recurrence in patients suffering from diverticular disease of the colon.