Deterministic storage and retrieval of telecom light from a quantum dot single-photon source interfaced with an atomic quantum memory

A hybrid interface of solid-state single-photon sources and atomic quantum memories is a long sought-after goal in photonic quantum technologies. Here, we demonstrate deterministic storage and retrieval of light from a semiconductor quantum dot in an atomic ensemble quantum memory at telecommunications wavelengths. We store single photons from an indium arsenide quantum dot in a high-bandwidth rubidium vapor-based quantum memory, with a total internal memory efficiency of (12.9 ± 0.4)%. The signal-to-noise ratio of the retrieved light field is 18.2 ± 0.6, limited only by detector dark counts.

Machine learning enhanced evaluation of semiconductor quantum dots

A key challenge in quantum photonics today is the efficient and on-demand generation of high-quality single photons and entangled photon pairs. In this regard, one of the most promising types of emitters are semiconductor quantum dots, fluorescent nanostructures also described as artificial atoms. The main technological challenge in upscaling to an industrial level is the typically random spatial and spectral distribution in their growth. Furthermore, depending on the intended application, different requirements are imposed on a quantum dot, which are reflected in its spectral properties. Given that an in-depth suitability analysis is lengthy and costly, it is common practice to pre-select promising candidate quantum dots using their emission spectrum. Currently, this is done by hand. Therefore, to automate and expedite this process, in this paper, we propose a data-driven machine-learning-based method of evaluating the applicability of a semiconductor quantum dot as single photon source. For this, first, a minimally redundant, but maximally relevant feature representation for quantum dot emission spectra is derived by combining conventional spectral analysis with an autoencoding convolutional neural network. The obtained feature vector is subsequently used as input to a neural network regression model, which is specifically designed to not only return a rating score, gauging the technical suitability of a quantum dot, but also a measure of confidence for its evaluation. For training and testing, a large dataset of self-assembled InAs/GaAs semiconductor quantum dot emission spectra is used, partially labelled by a team of experts in the field. Overall, highly convincing results are achieved, as quantum dots are reliably evaluated correctly. Note, that the presented methodology can account for different spectral requirements and is applicable regardless of the underlying photonic structure, fabrication method and material composition. We therefore consider it the first step towards a fully integrated evaluation framework for quantum dots, proving the use of machine learning beneficial in the advancement of future quantum technologies.

POS0173 DATA-DRIVEN MRI DEFINITIONS FOR ACTIVE AND STRUCTURAL SACROILIAC JOINT LESIONS IN JUVENILE SPONDYLOARTHRITIS TYPICAL OF AXIAL DISEASE

Background

For classification in juvenile spondyloarthritis (JSpA), it is important to develop cut-offs for active and structural lesions typical of axial disease on MRI that are readily and consistently interpreted. Since the maturing sacroiliac joint (SIJ) looks different from the adult SIJ, the criteria developed for positive MRI in adults may not be applicable in JSpA.

Objectives

As part of a study developing classification criteria for axial disease in JSpA, we aimed to determine quantitative SIJ imaging lesion cut-offs for inflammatory and structural lesions typical of axial JSpA using majority imaging expert decision as the reference criterion.

Methods

Subjects were a retrospective cohort of children with SpA who met the provisional Pediatric Rheumatology International Trials Organization criteria for enthesitis/spondylitis-related juvenile idiopathic arthritis or had a rheumatologist JSpA diagnosis. All subjects had symptom onset prior to age 18 years and underwent MRI as part of a diagnostic evaluation for axial disease. To enable SIJ quadrant-based scoring, all MRIs included semi-coronal slices through the cartilaginous part of the joint on fluid sensitive sequences and on T1-weighted sequences for the assessment of inflammation and structural lesions, respectively. MRIs were reviewed by 6 musculoskeletal imaging experts who were blinded to clinical details. MRI evaluation of the SIJ was based on standardized lesion definitions that were decided by consensus of the central imaging team and represented a mix of definitions from ASAS and the Juvenile Arthritis MRI Score Outcome Measures in Rheumatology working group. Using a web-based interface, raters globally assessed the presence or absence of lesions typical of axial SpA and performed SIJ quadrant or joint based scoring. Lesion scores were generated by averaging the scores of all raters. Sensitivity and specificity of lesion cut-offs were calculated using rater majority (≥4/6 raters) on a global assessment of the presence/absence of active or structural lesions typical of axial SpA with high confidence (confidence of ±3 or stronger on confidence scale from -5, “Definitely No”, to +5, “Definitely Yes”) as the reference standard.

Results

Imaging from 243 subjects, 61% male, median age 14.9 years, had sequences available for detailed MRI scoring. Active inflammatory lesion typical of axial disease in JSpA was defined as bone marrow edema (BME) in at least 3 SIJ quadrants (sensitivity 98.6%, specificity 96.5%). For structural lesion typical of axial JSpA, the optimal cut-off was erosion in at least 3 quadrants or at least one of the following lesions in at least 2 SIJ quadrants: sclerosis, fat lesion, backfill, ankylosis (sensitivity 98.6%, specificity 95.5%).

Conclusion

We propose data-driven cut-offs for active inflammatory and structural lesions on MRI typical of axial disease in JSpA that have high specificity and sensitivity using central imaging global assessment as the reference standard.

Table 1.

Performance of cut-offs for inflammatory and structural lesions of axial disease

Cut-offs for number of SIJ quadrants (any location)Sensitivity (95% CI)Specificity (95% CI)Definite active lesionBME score ≥2100 (95.0-100)93.5 (88.7-96.7)BME score ≥398.6 (92.5-100)96.5 (92.5-98.7)BME, same location on ≥3 consecutive slices88.6 (78.7-94.9)98.8 (95.8-99.9)Definite structural lesionErosion ≥295.7 (88-99.1)96.8 (92.7-99)Erosion, same location on ≥2 consecutive slices94.3 (86-98.4)98.1 (94.5-99.6)Erosion ≥391.4 (82.3-96.8)98.7 (95.4-99.8)Sclerosis ≥262.9 (50.5-74.1)98.1 (94.5-99.6)Fat lesion ≥222.9 (13.7-34.4%)98.7 (95.4-99.8%)Backfill ≥220 (11.4-31.3)100 (97.7-100)Ankylosis ≥21.3 (0.2-4.7)100 (94.9-100)ANY of the following in ≥2 SIJ quadrants: erosion, sclerosis, fat lesion, backfill, ankylosis98.6 (92.3-100)93.6 (88.5-96.9)Erosion ≥3 quadrants OR ≥2 quadrants of at least one of the following lesions: sclerosis, fat, backfill, ankylosis98.6 (92.3-100.0)95.5 (91.0-98.2)

Disclosure of Interests

Pamela F. Weiss Consultant of: Pfizer

Novartis

Biogen

Lilly

(All <$5K in the past fiscal year), Timothy G. Brandon: None declared, Amita Aggarwal: None declared, Ruben Burgos-Vargas Speakers bureau: Not in the last three years.

Novartis, Consultant of: Not in the last four years.

BMS, Lilly, Novartis, Robert A. Colbert: None declared, Gerd Horneff Speakers bureau: Pfizer, Novartis, Janssen, Chugai, Abbvie, Grant/research support from: Pfizer, Novartis, MSD, Chugai, Roche, Abbvie, Rik Joos Speakers bureau: Galapagos, Pfizer, AbbVie, Novartis, Amgen, BMS, Lilly, Grant/research support from: Pfizer, AbbVie, Roche, Ronald Laxer Consultant of: Abbvie, Novartis, Sobi, Sanofi, Eli Lilly Canada, Eli Lilly, Kirsten Minden Speakers bureau: Pfizer, Novartis, Consultant of: Pfizer, Novartis, Angelo Ravelli Speakers bureau: Abbvie, Novartis, SOBI, Angelini, Reckitt-Benkiser, Roche, Pfizer, Alexion, Grant/research support from: Novartis, Pfizer, Nicolino Ruperto Speakers bureau: NR has received honoraria for consultancies or speaker bureaus from the following pharmaceutical companies in the past 3 years: 2 Bridge, Amgen, AstraZeneca, Aurinia, Bayer, Brystol Myers and Squibb, Celgene, inMed, Cambridge Healthcare Research, Domain Therapeutic, EMD Serono, Glaxo Smith Kline, Idorsia, Janssen, Eli Lilly, Novartis, Pfizer, Sobi, UCB., Consultant of: NR has received honoraria for consultancies or speaker bureaus from the following pharmaceutical companies in the past 3 years: 2 Bridge, Amgen, AstraZeneca, Aurinia, Bayer, Brystol Myers and Squibb, Celgene, inMed, Cambridge Healthcare Research, Domain Therapeutic, EMD Serono, Glaxo Smith Kline, Idorsia, Janssen, Eli Lilly, Novartis, Pfizer, Sobi, UCB., Grant/research support from: The IRCCS Istituto Giannina Gaslini (IGG), where NR works as full-time public employee has received contributions from the following industries in the last 3 years: Bristol Myers and Squibb, Eli-Lilly, F Hoffmann-La Roche, Novartis, Pfizer, Sobi. This funding has been reinvested for the research activities of the hospital in a fully independent manner, without any commitment with third parties., Judith Smith Consultant of: Consulting panel of pediatric rheumatologists identifying issues in juvenile spondyloarthritis for Novartis. Paid < $5000, Matthew L. Stoll Consultant of: Currently consulting for Novartis, Shirley ML Tse: None declared, Filip van den Bosch Speakers bureau: Abbvie, Eli Lilly, Galapagos, Janssen, Novartis, Pfizer, UCB, Paid instructor for: Amgen, Eli Lilly, Consultant of: Abbvie, Eli Lilly, Galapagos, Janssen, Novartis, Pfizer, UCB, Robert G Lambert Paid instructor for: Novartis, Consultant of: CARE Arthritis, Calyx, Image Analysis Group, Novartis, David M. Biko Employee of: Merck (1998-2000), Nancy A. Chauvin Employee of: Forest Pharmaceuticals - Research scientist (1996) and Novartis - Pharmaceutical sales representative (1997), Michael L. Francavilla: None declared, Jacob L Jaremko: None declared, Nele Herregods: None declared, Ozgur Kasapcopur Speakers bureau: Pfizer, Abbvie, Novartis and Roche, Mehmet YILDIZ: None declared, Alison M. Hendry: None declared, Walter P Maksymowych Speakers bureau: Abbvie, Eli-Lilly, Janssen, Novartis, Pfizer, UCB Pharma, Consultant of: AbbVie, Boehringer Ingelheim, Celgene, Eli Lilly, Galapagos, Janssen, Novartis, Pfizer, UCB Pharma, Grant/research support from: Abbvie, Novartis, Pfizer

Highly Polarized Single Photons from Strain-Induced Quasi-1D Localized Excitons in WSe2

Single photon emission from localized excitons in two-dimensional (2D) materials has been extensively investigated because of its relevance for quantum information applications. Prerequisites are the availability of photons with high purity polarization and controllable polarization orientation that can be integrated with optical cavities. Here, deformation strain along edges of prepatterned square-shaped substrate protrusions is exploited to induce quasi-one-dimensional (1D) localized excitons in WSe₂ monolayers as an elegant way to get photons that fulfill these requirements. At zero magnetic field, the emission is linearly polarized with 95% purity because exciton states are valley hybridized with equal shares of both valleys and predominant emission from excitons with a dipole moment along the elongated direction. In a strong field, one valley is favored and the linear polarization is converted to high-purity circular polarization. This deterministic control over polarization purity and orientation is a valuable asset in the context of integrated quantum photonics.

Quantum dot-based broadband optical antenna for efficient extraction of single photons in the telecom O-band

Long-distance fiber-based quantum communication relies on efficient non-classical light sources operating at telecommunication wavelengths. Semiconductor quantum dots are promising candidates for on-demand generation of single photons and entangled photon pairs for such applications. However, their brightness is strongly limited due to total internal reflection at the semiconductor/vacuum interface. Here we overcome this limitation using a dielectric antenna structure. The non-classical light source consists of a gallium phosphide solid immersion lens in combination with a quantum dot nanomembrane emitting single photons in the telecom O-band. With this device, the photon extraction is strongly increased in a broad spectral range. A brightness of 17% (numerical aperture of 0.6) is obtained experimentally, with a single photon purity of g⁽²⁾(0)=0.049±0.02 at saturation power. This brings the practical implementation of quantum communication networks one step closer.

Diagnositic value of pelvic enthesitis on MRI of the sacroiliac joints in enthesitis related arthritis

BACKGROUND

To determine the prevalence and diagnostic value of pelvic enthesitis on MRI of the sacroiliac (SI) joints in enthesitis related arthritis (ERA).

METHODS

We retrospectively studied 143 patients aged 6-18 years old who underwent MRI of the SI joints for clinically suspected sacroiliitis between 2006-2014. Patients were diagnosed with ERA according to the International League of Associations for Rheumatology (ILAR) criteria. All MRI studies were reassessed for the presence of pelvic enthesitis, which was correlated to the presence of sacroiliitis on MRI and to the final clinical diagnosis. The added value for detection of pelvic enthesitis and fulfilment of criteria for the diagnosis of ERA was studied.

RESULTS

Pelvic enthesitis was seen in 23 of 143 (16 %) patients. The most commonly affected sites were the entheses around the hip (35 % of affected entheses) and the retroarticular interosseous ligaments (32 % of affected entheses). MRI showed pelvic enthesitis in 21 % of patients with ERA and in 13 % of patients without ERA. Pelvic enthesitis was seen on MRI in 7/51 (14 %) patients with clinically evident enthesitis, and 16/92 (17 %) patients without clinically evident enthesitis. In 7 of 11 ERA-negative patients without clinical enthesitis but with pelvic enthesitis on MRI, the ILAR criteria could have been fulfilled, if pelvic enthesitis on MRI was included in the criteria. There is a high correlation between pelvic enthesitis and sacroiliitis, with sacroiliitis present in 17/23 (74 %) patients with pelvic enthesitis.

CONCLUSIONS

Pelvic enthesitis may be present in children with or without clinically evident peripheral enthesitis. There is a high correlation between pelvic enthesitis and sacroiliitis on MRI of the sacroiliac joints in children. As pelvic enthesitis indicates active inflammation, it may play a role in assessment of the inflammatory status. Therefore, it should be carefully sought and noted by radiologists examining MRI of the sacroiliac joints in children.

Methotrexate in combination with other DMARDs is not superior to methotrexate alone for remission induction with moderate-to-high-dose glucocorticoid bridging in early rheumatoid arthritis after 16 weeks of treatment: the CareRA trial

Objectives

To compare the efficacy and safety of intensive combination strategies with glucocorticoids (GCs) in the first 16 weeks (W) of early rheumatoid arthritis (eRA) treatment, focusing on high-risk patients, in the Care in early RA trial.

Methods

400 disease-modifying antirheumatic drugs (DMARD)-naive patients with eRA were recruited and stratified into high risk or low risk according to classical prognostic markers. High-risk patients (n=290) were randomised to 1/3 treatment strategies: combination therapy for early rheumatoid arthritis (COBRA) Classic (methotrexate (MTX)+ sulfasalazine+60 mg prednisone tapered to 7.5 mg daily from W7), COBRA Slim (MTX+30 mg prednisone tapered to 5 mg from W6) and COBRA Avant-Garde (MTX+leflunomide+30 mg prednisone tapered to 5 mg from W6). Treatment modifications to target low-disease activity were mandatory from W8, if desirable and feasible according to the rheumatologist. The primary outcome was remission (28 joint disease activity score calculated with C-reactive protein <2.6) at W16 (intention-to-treat analysis). Secondary endpoints were good European League Against Rheumatism response, clinically meaningful health assessment questionnaire (HAQ) response and HAQ equal to zero. Adverse events (AEs) were registered.

Results

Data from 98 Classic, 98 Slim and 94 Avant-Garde patients were analysed. At W16, remission was reached in 70.4% Classic, 73.6% Slim and 68.1% Avant-Garde patients (p=0.713). Likewise, no significant differences were shown in other secondary endpoints. However, therapy-related AEs were reported in 61.2% of Classic, in 46.9% of Slim and in 69.1% of Avant-Garde patients (p=0.006).

Conclusions

For high-risk eRA, MTX associated with a moderate step-down dose of GCs was as effective in inducing remission at W16 as DMARD combination therapies with moderate or high step-down GC doses and it showed a more favourable short-term safety profile.

EudraCT number:

2008-007225-39.

Sensitivity and specificity of criteria for spondyloarthritis in children with late onset pauciarticular juvenile chronic arthritis as well as their characteristics

OBJECTIVE

To evaluate the sensitivity and specificity of criteria designed for spondyloarthritis in a university hospital treated population of children with late onset pauciarticular juvenile chronic arthritis and a control population.

METHODS

Four sets of criteria especially designed for juvenile patients: Garmisch-Partenkirchen juvenile spondylitis criteria (= Garmisch), SEA (=seronegative enthesopathy and arthritis) syndrome, Enthesitis Related Arthritis (ERA), Atypical spondyloarthritis for children and two sets of criteria for patients without age specification (European spondyloarthropathy Study Group - ESSG and Amor) were evaluated in a cross-sectional way in a group of 43 consecutive patients with late onset pauciarticular juvenile chronic arthritis (LOPA) seen over a six-month period in the outpatient clinic. These criteria were analysed in 69 patients with other forms of juvenile chronic arthritis as well. The sensitivity and specificity were calculated for each set, as well as positive predictive value and likelihood ratio. The characteristics described in the different sets of criteria were separately evaluated in the LOPA patients and the other patients.

RESULTS

For sensitivity, the Garmisch criteria scored the highest value (97.7%). However, sensitivity was significantly lower in two of the juvenile sets (SEA syndrome and Atypical spondyloarthritis), respectively 44.2% and 51.2%, as opposed to the other criteria (>85%; p<0.01 by Mc Nemar test). Specificity and positive predictive value (PPV) was the highest for the SEA syndrome criteria (98.5%, vs. 95.0%) followed by the ERA (95.6 % vs. 92.1 %) and the Garmisch criteria (94.2% vs. 91.3%). The positive likelihood ratio (LR+) was >10 in SEA (30.5), ERA (18.7) and Garmisch (16.8). The negative likelihood ratio (LR-) was <0.1 only in the Garmisch criteria (0.02).

CONCLUSION

Sensitivity, specificity, PPV, LR+ and LR- for the Garmisch-Partenkirchen criteria suggest that they classify almost the same population as defined by LOPA. The SEA syndrome criteria, which were not designed to be classification criteria, being very specific, cannot be used in this patient population to classify a sufficient number of patients. The sensitivity and specificity for the ESSG criteria being similar in these children as in adults suggest they have similar characteristics. The Garmisch-Partenkirchen criteria and/or LOPA definition are major candidates for future research in identifying spondyloarthritis in juvenile patients.

Juvenile-onset systemic lupus erythematosus: different clinical and serological pattern than adult-onset systemic lupus erythematosus

OBJECTIVE

To investigate differences in clinical signs and symptoms, and in antinuclear antibodies (ANA), between patients with juvenile-onset and adult-onset systemic lupus erythematosus (SLE).

METHODS

Clinical and serological data of 56 patients with juvenile-onset SLE were compared with data of 194 patients with adult-onset SLE. ANA were determined by line immunoassay and by indirect immunofluorescence on Crithidia luciliae.

RESULTS

Renal involvement, encephalopathy and haemolytic anaemia were seen, and anti-dsDNA, anti-ribosomal P and antihistone antibodies found, significantly more often in juvenile-onset SLE. Anti-dsDNA antibodies were directly associated, and anti-ribosomal P antibodies inversely associated, with renal involvement in juvenile-onset SLE. In juvenile patients with SLE and anti-dsDNA and without anti-ribosomal P antibodies the odds ratio for glomerulonephritis was 9.00; no patients with anti-ribosomal P but without anti-dsDNA had renal involvement.

CONCLUSION

Patients with juvenile-onset SLE more often have renal involvement and encephalopathy than patients with adult-onset SLE. Anti-ribosomal P, anti-dsDNA and antihistone antibodies are more often found in patients with juvenile-onset SLE.

Expressive dimensions of pain catastrophizing: a comparative analysis of school children and children with clinical pain

We investigated the role of the child's pain catastrophizing in explaining (1) children's self-reported tendency to verbally share their pain experience with others and (2) different dimensions of pain expression, as described by the mother and the father, including non-verbal and verbal communicative pain behaviour and protective pain behaviour. Participants were school children, children with chronic or recurrent pain, and their parents. The results showed that: (1) Pain catastrophizing was associated with children's greater self-acknowledged tendency to verbally share their pain experience with others. (2) Mothers and fathers perceived highly catastrophizing children to be more communicative about their pain. (3) The role of pain catastrophizing in the child's verbal sharing of pain experiences and in explaining expressive behaviour as rated by parents did not differ between the school children and children with recurrent and chronic pain. (4) Nevertheless, findings indicated marked differences between school children and the clinical sample. Children of the clinical sample experienced more severe pain, more pain catastrophizing, more protective pain behaviour, but less verbal communications about their pain. These results further corroborate the position that catastrophic thoughts about pain have interpersonal consequences. Findings are discussed in terms of the possible functions and effects upon others of pain catastrophizing and associated categories of pain behaviour.

Effect of age on prevalence of anticitrullinated protein/peptide antibodies in polyarticular juvenile idiopathic arthritis

OBJECTIVES

Anticitrullinated protein/peptide antibodies (ACPA) have an excellent diagnostic performance for rheumatoid arthritis (RA). Despite similarities between RA and polyarticular juvenile idiopathic arthritis (JIA), the prevalence of ACPA in polyarticular JIA is low. We wanted to evaluate the influence of age, disease duration and total immunoglobulin G (IgG) concentration on ACPA positivity in this cohort.

METHODS

Patients with JIA were classified according to age and International League of Associations for Rheumatology classification. Sixty-one JIA patients aged less than 16 yr were included and classified as polyarticular JIA (poly JIA <16; n=23) or non-polyarticular JIA (n=38). In addition, a group of 21 polyarticular JIA patients, aged more than 16 yr (poly JIA >16) and a group of 51 RA patients were included. Antibodies to the synthetic citrullinated peptides pepA and pepB were detected by line immunoassay and antibodies to cyclic citrullinated peptides (CCP2) by enzyme-linked immunosorbent assay. Serum IgG was measured by fixed-time immunonephelometry.

RESULTS

No ACPA reactivity was observed in the non-polyarticular group. In poly JIA <16, only 1/23 had anti-CCP2 antibody, whereas in poly JIA >16 patients a significantly higher fraction was detected (6/21). All but one of the anti-CCP2 reactive patients were rheumatoid factor (RF) positive. Assessing anti-CCP2 antibody concentration as a continuous variable, significantly higher titres were found in poly JIA >16 compared with poly JIA <16. No correlation between anti-CCP2 concentration and total IgG was detected. Four patients demonstrated immunoreactivity against pepA and pepB; all of them were anti-CCP2 reactive, poly JIA >16 patients.

CONCLUSIONS

ACPA are present in low prevalence in polyarticular JIA and are particularly found in the RF-positive subset. With age, a significant increase in anti-CCP2 positivity is observed in polyarticular JIA patients.

The Belgian-Flemish version of the Childhood Health Assessment Questionnaire (CHAQ) and the Child Health Questionnaire (CHQ)

We report herein the results of the cross-cultural adaptation and validation into the Belgian-Flemish language of the parent's version of two health related quality of life instruments. The Childhood Health Assessment Questionnaire (CHAQ) is a disease specific health instrument that measures functional ability in daily living activities in children with juvenile idiopathic arthritis (JIA). The Child Health Questionnaire (CHQ) is a generic health instrument designed to capture the physical and psychosocial well-being of children independently from the underlying disease. The Belgian-Flemish CHAQ was fully validated with 3 forward and 3 backward translations, while the Belgian-Flemish CHQ was equal to the Dutch version and revalidated in this study. The French version of both CHAQ and CHQ was exactly the same as the one used in France. A total of 199 subjects were enrolled: 53 patients with JIA (11% systemic onset, 40% polyarticular onset, 13% extended oligoarticular subtype, and 36% persistent oligoarticular subtype) and 146 healthy children. The CHAQ clinically discriminated between healthy subjects and JIA patients, with the polyarticular onset, and extended oligoarticular subtypes having a higher degree of disability, pain, and a lower overall well-being when compared to their healthy peers. Also the CHQ clinically discriminated between healthy subjects and JIA patients, with the polyarticular onset and extended oligoarticular subtypes having a lower physical and psychosocial well-being when compared to their healthy peers. In conclusion the Belgian-Flemish version of the CHAQ-CHQ is a reliable, and valid tool for the functional, physical and psychosocial assessment of children with JIA.

Occurrence of scleroderma in monozygotic twins

Familial occurrence of scleroderma is rare and concordance for the disease in twins has been reported exceptionally. We describe 2 female identical twin pairs concordant for scleroderma. The first twin pair was diagnosed with the systemic form of scleroderma, the second pair with the localized form.

Favourable outcome in 135 children with juvenile systemic sclerosis: results of a multi-national survey

OBJECTIVE

To increase the current knowledge of the outcome of juvenile systemic sclerosis (jSSc), which is currently limited.

METHODS

In order to investigate the patient outcome and prognostic factors, starting October 1994, we distributed questionnaires to 324 paediatric rheumatology centres.

RESULTS

Until 15 May 1998 responses from 46 centres were received, 34 of which returned completed questionnaires on a total of 135 patients. One hundred and twenty-two of the 135 patients were Caucasian, 100 were female. The mean age at disease onset was 8.8 yr (S.D. +/- 3.3 yr). The mean disease duration at the last follow-up was 5 yr(S.D. +/- 3.3 yr). At the last follow-up the disease was still active and required medication in 82 patients, 36 had inactive disease on medication, and 16 were in remission. Ninety per cent of the living patients were fully active in daily life at the last follow-up. Eight of the 135 patients had died. These patients had a median age at onset of the disease of 10.5 yr (range 6.7-15.8 yr). The median disease duration until death was 2 yr (range 1-8 yr). The causes of death were heart failure (five), renal failure (one), sepsis (one) and in one case the cause was not defined. The 1 yr survival rate was 99%, the 2 yr was 97% and the 4 yr was 95%.

CONCLUSIONS

At a mean follow-up of 5 yr, the current results show a favourable outcome in most patients with childhood onset jSSc and a significantly better survival than in the adult SSc patients.

Eosinophilic myositis resulting from sarcocystosis

Muscle sarcocystosis is a parasitic infection acquired by ingestion of sporocysts of Sarcocystis species. A case is described where symptoms of fever, chronic myositis and eosinophilia were present. Diagnosis was made via muscle biopsy. Improvement and cure coincided with treatment with cotrimoxazole. A limited review of human muscle sarcocystosis and an outline of the gaps in the knowledge of this infection is presented.

Gut inflammation in children with late onset pauciarticular juvenile chronic arthritis and evolution to adult spondyloarthropathy--a prospective study

Ileocolonoscopy with biopsy of the colon and terminal ileum was performed prospectively on 12 patients under age 16 with late onset juvenile chronic arthritis (JCA). Inflammatory gut lesions were seen in 9 of these 12 patients; 4 were of the acute type, 5 of the chronic type. Chronic gut inflammation was related to axial inflammatory complaints, inflammatory serum variables, thrombocytosis and sacroiliac radiological abnormalities. A 2nd ileocolonoscopy was performed on 5 of the 12 patients, and a 3rd ileocolonoscopy on 2 of these with persistent synovitis. Gut inflammation and joint inflammation were related; moreover, all 5 patients had chronic inflammatory lesions by the time of the last investigation, one presented with Crohn's disease. The 12 patients were reviewed 3 to 9 years after the first ileocolonoscopy. Four patients were in remission, including the 3 patients with initial normal gut histology. Five patients had developed ankylosing spondylitis (AS), a 6th patient possible AS. Axial inflammatory complaints, a family history of spondyloarthropathies, HLA-B27 positivity, early sacroiliac and peripheral joints radiographic changes, persistence of inflammatory serum variables, thrombocytosis and chronic inflammatory lesions on gut biopsy, are predictive factors in juveniles for evolution to AS. Late onset pauciarticular JCA represents a form of spondyloarthropathy similar to adolescent forms. Persistent gut inflammation could play a role in the pathogenesis of the disease and persistent synovitis.

Juvenile spondyloarthropathies in 1992

There is some evidence that patients with late onset pauciarticular juvenile chronic arthritis (JCA) should be included among those with spondyloarthropathies, at least during the course of their disease, even if at the onset of the disease we prefer to label them as patients with JCA. The clinical symptoms which could allow us to classify them as spondyloarthritic are frequently absent at the onset of the disease. The gut seems to play a role in the pathogenesis of this form of JCA, though the exact mechanisms must be elucidated further.

Sulfasalazine treatment in juvenile chronic arthritis: an open study

In an open study, the effect of sulfasalazine was evaluated in the treatment of juvenile chronic arthritis (JCA). Forty-one patients, i.e., 27 boys and 14 girls with JCA under 16 years of age, were included in the study. In all of them, treatment with nonsteroidal antiinflammatory drugs (NSAID) had been unable to control the disease. The patients were divided in 4 subgroups depending on the mode of onset and evolution (Type I = systemic onset, Type II = polyarticular form. Type IIIa and Type IIIb = pauciarticular form). Remission was achieved in 21 patients, significant improvement in 12. Status was unchanged in 4 patients and worsened in 3. In 5 patients side effects were observed, which forced interruption of treatment in 4. Sulfasalazine was stopped in 7 patients: for toxicity in 4 and for inefficacy in 3. In 7 other patients the treatment was terminated after a prolonged remission. These promising results must be confirmed in a double blind versus placebo study, preferably restricted to type III JCA.

Gold-induced aplastic anemia

Three patients receiving gold salt treatment for rheumatoid arthritis developed severe aplastic anemia. All three patients experienced remission of their disease at the time of the occurrence of marrow aplasia. Reviewing data on these patients and recent literature indicate that fatal marrow aplasia seems to occur more frequently in sero-negative women who respond well to therapy with gold salts. Frequent blood monitoring in search for any pronounced or sustained drop in red, white or platelet count, even within normal range could serve as a warning sign for myelotoxicity. Despite intensive supportive measures and specific therapeutic attempts, all three patients eventually died of septic shock.

Late onset pauciarticular juvenile chronic arthritis: relation to gut inflammation

Ileocolonoscopy with biopsy of the ileum, ileocecal valve and cecum was performed on 32 patients (22 males, 10 females) with juvenile chronic arthritis (JCA) with pauciarticular onset. Mean age at onset of disease was 12 years. Ankylosing spondylitis (AS) was diagnosed in 13 patients; the other 19 cases were classified as reactive arthritis with recurrent or persistent pauciarticular synovitis. Twenty-two patients (68%) were HLA-B27 positive; 8 patients (25%) carried the HLA-Bw62 antigen. Ileocolonoscopy was performed 6 months to 32 years after the initial manifestation of the disease (mean : 9 years). Fourteen patients had macroscopic lesions of the ileum and ileocecal valve although only 8 of these had a history of intestinal complaints. Twenty-six patients (81%) presented histological signs of gut inflammation. Most of the gut abnormalities were classified as active chronic or Crohn-like lesions (19/26). Only 7 patients had acute or bacterial enteritis-like lesions. Acute lesions were seen in only one patient with AS. All but 2 patients with sacroiliitis, in whom signs of gut inflammation were found, had active chronic lesions. All the 8 HLA-Bw62 positive patients had histological evidence of gut inflammation. Only chronic or Crohn-like lesions were found. In the majority of patients with JCA with pauciarticular onset, gut inflammation was found on ileum biopsy. Some of their lesions are related to Crohn's disease, and the presence of the HLA-Bw62 antigen could predispose to the arthritis seen in these cases.

HLA antigens in seronegative spondylarthropathies. Reactive arthritis and arthritis in ankylosing spondylitis: relation to gut inflammation

The prevalence of HLA-A, B, C and DR antigens was determined and compared in 94 patients with reactive arthritis, 54 patients with ankylosing spondylitis (AS), 37 patients with inflammatory bowel disease (IBD) and in 1,010 apparently normal blood donors. The 185 patients all underwent ileocolonoscopy with biopsy of ileum, ileocecal valve and cecum. HLA-B27 was found elevated in the groups with reactive arthritis (48%, chi 2 = 82, p less than 0.0005) and the AS groups (78%, chi 2 = 157, p less than 0.0005), compared to healthy controls. HLA-Bw62 was significantly raised in the patients with reactive arthritis (34%, chi 2 = 73, p less than 0.0005) (particularly the HLA-B27 negatives (48%, chi 2 = 90, p less than 0.0005) and in the HLA-B27 negative patients with AS (25%, chi 2 = 5.5, p less than 0.02). This did not apply to the other patients with AS (4.7% NS). HLA-Bw62 could be associated with a specific clinical picture of asymmetrical pauciarticular arthritis, accompanied by enthesopathies and sacroiliitis classified as idiopathic reactive arthritis, especially when the disease is of enterogenic origin. The frequency of HLA-Bw62 was very high in patients with reactive arthritis and in patients with AS with active chronic (n = 39, 23%, chi 2 = 13, p less than 0.0005) and Crohn-like lesions (n = 14, 50%, chi 2 = 35, p less than 0.0005) on gut biopsy, normal in patients with acute lesions (n = 35, 11%, NS).(ABSTRACT TRUNCATED AT 250 WORDS)

Repeat ileocolonoscopy in reactive arthritis

Ileocolonoscopy on patients with HLA-B27 related disease, reactive arthritis and ankylosing spondylitis (AS) with peripheral arthritis, revealed the presence of inflammatory lesions in biopsy specimens from the ileum in 71 and 60% of the cases, respectively. A 2nd ileocolonoscopy was performed on 14 patients, 4 to 22 months after the first. In 6 of the 7 patients in articular clinical remission, the inflammatory gut lesions had disappeared. The gut biopsies of the 7 patients with active joint disease continued to show inflammatory lesions. One of these patients underwent a 3rd ileocolonoscopy after having gone into clinical remission, possibly secondary to treatment with sulfasalazine; the histology was completely normal. The strong relationship between clinical articular inflammation and gut inflammation seems to support the hypothesis that in B27 related diseases, repetitive exogenous triggering causing transgression of oral tolerance by increased gut permeability, provokes and maintains the joint inflammation.

Familial aggregation in seronegative spondyloarthritis of enterogenic origin. A family study

A family study of 2 probands, suffering from seronegative spondyloarthritis with ileocolonoscopic evidence of chronic inflammation of the ileum, is presented. On the father's side 2 brothers carry the HLA-Bw62 antigen. One developed typical Crohn's disease, the other showed chronic inflammatory signs of the ileum on biopsy. These lesions have frequently been demonstrated in reactive arthritis and ankylosing spondylitis (AS) with peripheral arthritis, in the absence of gastrointestinal symptoms. On the mother's side there were no clinical or histological signs of ileum inflammation, or spondyloarthritic features, although the mother carries the HLA-B27 antigen. The 4 children are all HLA-Bw62 and B27 positive, but only 2 of them have developed seronegative spondyloarthritis associated with histological evidence of chronic ileum inflammation. The familial aggregation of the seronegative spondyloarthritides is demonstrated. The lesions found on ileal biopsy in reactive synovitis and AS with peripheral arthritis may be related to Crohn's disease.

Sulphasalazine (Salazopyrin) in the treatment of enterogenic reactive synovitis and ankylosing spondylitis with peripheral arthritis

Sulphasalazine was administered to 48 patients with reactive synovitis (RS) and ankylosing spondylitis (AS) with peripheral arthritis, resistant to nonsteroidal anti-inflammatory drugs. Thirty-seven patients underwent an ileocolonoscopy and in 33 patients signs of chronic or active inflammation of the ileum and/or ileocecal valve were found. Forty-two patients improved after 3 to 12 months of treatment; 50 per cent of them went into remission. In most of the patients improvement failed to occur in the first 2 months of treatment. There was no recurrent disease activity in patients responding to the treatment. Adverse reactions were rare and did not necessitate interruption of treatment. The beneficial effect of sulphasalazine in the treatment of RS and AS with peripheral arthritis needs to be confirmed in double-blind controlled studies.