Reliability assessment of ultrasound muscle echogenicity in patients with rheumatic diseases: Results of a multicenter international web-based study

Objectives

To investigate the inter/intra-reliability of ultrasound (US) muscle echogenicity in patients with rheumatic diseases.

Methods

Forty-two rheumatologists and 2 radiologists from 13 countries were asked to assess US muscle echogenicity of quadriceps muscle in 80 static images and 20 clips from 64 patients with different rheumatic diseases and 8 healthy subjects. Two visual scales were evaluated, a visual semi-quantitative scale (0-3) and a continuous quantitative measurement ("VAS echogenicity," 0-100). The same assessment was repeated to calculate intra-observer reliability. US muscle echogenicity was also calculated by an independent research assistant using a software for the analysis of scientific images (ImageJ). Inter and intra reliabilities were assessed by means of prevalence-adjusted bias-adjusted Kappa (PABAK), intraclass correlation coefficient (ICC) and correlations through Kendall's Tau and Pearson's Rho coefficients.

Results

The semi-quantitative scale showed a moderate inter-reliability [PABAK = 0.58 (0.57-0.59)] and a substantial intra-reliability [PABAK = 0.71 (0.68-0.73)]. The lowest inter and intra-reliability results were obtained for the intermediate grades (i.e., grade 1 and 2) of the semi-quantitative scale. "VAS echogenicity" showed a high reliability both in the inter-observer [ICC = 0.80 (0.75-0.85)] and intra-observer [ICC = 0.88 (0.88-0.89)] evaluations. A substantial association was found between the participants assessment of the semi-quantitative scale and "VAS echogenicity" [ICC = 0.52 (0.50-0.54)]. The correlation between these two visual scales and ImageJ analysis was high (tau = 0.76 and rho = 0.89, respectively).

Conclusion

The results of this large, multicenter study highlighted the overall good inter and intra-reliability of the US assessment of muscle echogenicity in patients with different rheumatic diseases.

Reliability assessment of the definition of ultrasound enthesitis in SpA: results of a large, multicentre, international, web-based study

OBJECTIVES

To investigate the reliability of the OMERACT US Task Force definition of US enthesitis in SpA.

METHODS

In this web exercise, based on the evaluation of 101 images and 39 clips of the main entheses of the lower limbs, the elementary components included in the OMERACT definition of US enthesitis in SpA (hypoechoic areas, entheseal thickening, power Doppler signal at the enthesis, enthesophytes/calcifications, bone erosions) were assessed by 47 rheumatologists from 37 rheumatology centres in 15 countries. Inter- and intra-observer reliability of the US components of enthesitis was calculated using Light's kappa, Cohen's kappa, Prevalence And Bias Adjusted Kappa (PABAK) and their 95% CIs.

RESULTS

Bone erosions and power Doppler signal at the enthesis showed the highest overall inter-reliability [Light's kappa: 0.77 (0.76-0.78), 0.72 (0.71-0.73), respectively; PABAK: 0.86 (0.86-0.87), 0.73 (0.73-0.74), respectively], followed by enthesophytes/calcifications [Light's kappa: 0.65 (0.64-0.65), PABAK: 0.67 (0.67-0.68)]. This was moderate for entheseal thickening [Light's kappa: 0.41 (0.41-0.42), PABAK: 0.41 (0.40-0.42)], and fair for hypoechoic areas [Light's kappa: 0.37 (0.36-0.38); PABAK: 0.37 (0.37-0.38)]. A similar trend was observed in the intra-reliability exercise, although this was characterized by an overall higher degree of reliability for all US elementary components compared with the inter-observer evaluation.

CONCLUSIONS

The results of this multicentre, international, web-based study show a good reliability of the OMERACT US definition of bone erosions, power Doppler signal at the enthesis and enthesophytes/calcifications. The low reliability of entheseal thickening and hypoechoic areas raises questions about the opportunity to revise the definition of these two major components for the US diagnosis of enthesitis.

The Reliability of Ultrasound in the Assessment of Hyaline Cartilage in Rheumatoid Arthritis and Healthy Metacarpal Heads

PURPOSE

 i) To assess the inter- and intra-observer reliability of ultrasound (US) in the evaluation of the hyaline cartilage (HC) of the metacarpal head (MH) in patients with rheumatoid arthritis (RA) and in healthy subjects (HS) both qualitatively and quantitatively. ii) To calculate the smallest detectable difference (SDD) of the MH cartilage thickness measurement. iii) To correlate the qualitative scoring system and the quantitative assessment.

MATERIALS AND METHODS

 US examination was performed on 280 MHs of 20 patients with RA and 15 HS using a very high frequency probe (up to 22 MHz). HC status was evaluated both qualitatively (using a five-grade scoring system) and quantitatively (using the average value of the longitudinal and transverse measures). The HC of MHs from II to V metacarpophalangeal joint of both hands were scanned independently on the same day by two rheumatologists to assess inter-observer reliability. All subjects were re-examined using the same scanning protocol and the same US setting by one sonographer after a week to assess intra-observer reliability.

RESULTS

 The inter-observer agreement and intra-observer agreement were moderate to substantial (k = 0.66 and k = 0.73) for the qualitative scoring system and high (ICC = 0.93 and ICC = 0.94) for the quantitative assessment. The SDD of the MH cartilage thickness measurement was 0.09 mm. A significant correlation between the two scoring systems was found (r = -0.35; p < 0.001).

CONCLUSION

 The present study describes the main methodological issues of HC assessment. Using a standardized protocol, both the qualitative and the quantitative scoring systems can be reliable.

Clinical and Serological Features in Latin American IgG4-Related Disease Patients Differ According to Sex, Ethnicity, and Clinical Phenotype

BACKGROUND/OBJECTIVE

Data on IgG4-related disease (IgG4-RD) come almost exclusively from cohorts from Asia, Europe, and North America. We conducted this study to describe the clinical presentation, phenotype distribution, and association with sex, ethnicity, and serological markers in a large cohort of Latin American patients with IgG4-RD.

METHODS

We performed a multicenter medical records review study including 184 Latin American IgG4-RD patients. We assigned patients to clinical phenotypes: group 1 (pancreato-hepato-biliary), group 2 (retroperitoneal/aortic), group 3 (head and neck-limited), group 4 (Mikulicz/systemic), and group 5 (undefined). We focused the analysis on how sex, ethnicity, and clinical phenotype may influence the clinical and serological presentation.

RESULTS

The mean age was 50.8 ± 15 years. Men and women were equally affected (52.2% vs 48.8%). Fifty-four patients (29.3%) were assigned to group 1, 21 (11.4%) to group 2, 57 (30.9%) to group 3, 32 (17.4%) to group 4, and 20 (10.8%) to group 5. Male sex was associated with biliary tract (odds ratio [OR], 3.4; 95% confidence interval [CI], 1.36-8.26), kidney (OR, 3.4; 95% CI, 1.28-9.25), and retroperitoneal involvement (OR, 5.3; 95% CI, 1.45-20). Amerindian patients presented more frequently with atopy history and gallbladder involvement. Group 3 had a female predominance.

CONCLUSIONS

Latin American patients with IgG4-RD were younger, and men and women were equally affected compared with White and Asian cohorts. They belonged more commonly to group 1 and group 3. Retroperitoneal and aortic involvement was infrequent. Clinical and serological features differed according to sex, ethnicity, and clinical phenotype.

Ultrasound-Guided Procedures in Rheumatology Daily Practice: Feasibility, Accuracy, and Safety Issues

BACKGROUND/OBJECTIVE

The aims of this study were to describe in detail the ultrasound (US)-guided procedures in our daily rheumatology practice, to evaluate the feasibility and accuracy of US-guided procedures, and to test the efficacy of our disinfection protocol in preventing infectious complications.

METHODS

This was a cross-sectional and monocentric study. Information regarding patients' age, sex, body mass index, rheumatic disease, US pathological findings, aspirated and/or injected anatomical site, US equipment (ie, probe type and frequency), and needle type was consecutively collected for each US-guided procedure in a third-level rheumatology center.

RESULTS

A total of 643 US-guided procedures were performed, with a mean of 5.2 procedures per working-day. In 94.2% of the patients, only one procedure was carried out, whereas in 5.8%, more than one. The mean time was 7 ± 2.5 minutes. Ultrasound-guided procedures were highly accurate (accuracy rate higher than 95%) and safe (adverse events were reported in 0.8%). Our disinfection protocol was effective in preventing infectious complications. Probes with frequency values between 8 to 13 MHz and 20-, 21-, and 22-gauge needles were the most frequently used at shoulder, knee, wrist, elbow, and ankle level. High-frequency linear probes (ranging between 18 and 22 MHz) and 23- and 25-gauge needles were used for injecting small joints of the hands and feet. Convex low-frequency probe (2-7 MHz) and 18- and 20-gauge needles were the most used for performing hip joint aspirations and/or injections.

CONCLUSIONS

This study reports useful information for setting up a service providing US-guided procedures in rheumatology and supports the feasibility, accuracy, and safety of US-guided procedures.

Multicenter study to assess presenteeism in systemic lupus erythematosus and its relationship with clinical and sociodemographic features

Objective The aim of this study was to measure presenteeism (productivity impairment while the patient is at work) and the related risk factors in patients with systemic lupus erythematosus (SLE) from Argentina. Methods A total of 130 consecutive (1997 American College of Rheumatology (ACR) criteria) working patients with SLE were assessed using a standardized data collection form. Sociodemographic, disease and work-related variables were collected. The Work Productivity and Activity Impairment (WPAI) questionnaire was performed. Results Overall, 130 patients were included in the analysis; 91% were women, and the mean age was 39 years (range 19-77). A total of 43% were White, 43% Mestizo and 13% Amerindian. Overall, 38% were single and 38% were married. A total of 75% had more than 12 years of formal education. The median disease duration was 7 years (interquartile range 25-75 (IQR) 4-13). Median Systemic Lupus Erythematosus Disease Activity Index (SLEDAI) score was 0 (IQR 0-2), and median Systemic Lupus International Collaborating Clinics/ACR Damage Index (SLICC-SDI) score was 0 (IQR 0-1). Lupus quality of life (LupusQoL) domains scores were: physical health 87 (IQR 70-96), emotional health 78 (IQR 54-91), burden to others 75 (IQR 50-92), intimate relationships 87 (IQR 50-100), and body image 85 (IQR 70-100). Absenteeism was 8%, presenteeism was 19%, and overall work impairment (absenteeism + presenteeism) was 26%. In the multiple regression analysis, considering presenteeism as dependent variable, (adjusting by age, disease duration, >12 years of education, Non-white race, Visual Analogue Scale (VAS) pain, VAS fatigue, SLICC-SDI, LupusQoL, physical and emotional domains), we found that SLICC-SDI (odds ratio (OR) 1.68, confidence interval (CI) 1-2.7) and Non-white race (OR 3.27, CI 1.04-10) were related to presenteeism and >12 years of education (OR 0.30, CI 0.09-0.98) and higher scores of LupusQoL emotional health domain (OR 0.95, CI 0.92-0.98) were protective. Conclusions organ damage and Non-white race were significantly associated with presenteeism while >12 years of education and higher scores of LupusQoL emotional health domain were protective.

B Cell Lymphoma mimicking Rheumatoid Arthritis

Non Hodking´s lymphoma (NHL) may involve bones but synovial involvement is uncommon. We describe a patient who presented with polyarthritis, sicca symptoms and rash suggestive of rheumatoid arthritis. An atypical skin rash prompted skin and synovial biopsies. A diagnosis of synovial and skin malignant large B-cell lymphoma anaplastic subtype was performed. Chemotherapy with dexamethasone, vincristine and rituximab was started. Following treatment the patient had complete resolution of cutaneous and articular lymphoma manifestations.