Ultrasound and magnetic resonance imaging assessment of joint disease in symptomatic patients with cystic fibrosis arthropathy.

OBJECTIVES: Cystic fibrosis arthropathy (CFA) is a term commonly used for joint pain with and without swelling seen in some patients with CF. Early studies into CFA focused on the presence of rheumatoid factor and immunological changes on synovial biopsy, with parallels drawn between respiratory and joint activity. Identification of anti-cyclic citrullinated peptide antibodies (anti-CCP) as a marker of rheumatoid arthritis (RA), along with increased access to sensitive imaging techniques including ultrasound (US) and magnetic resonance imaging (MRI), offer great potential to investigate and more accurately understand the type(s) of inflammatory arthritis that may underlie CFA. The aim of this study was to phenotype an active CFA cohort using serology and imaging, as a basis for further work in this understudied area. METHODS: This was a prospective observational cohort study of symptomatic CFA patients presenting with joint pain. Participants underwent serological testing, clinical and US joint and entheseal assessment, as well as MRI of the most symptomatic joint/joint area. RESULTS: Ten symptomatic patients were studied with 9/10 having positive clinical findings. Inflammatory changes on US were seen in 8/10 cases. Five patients had positive findings on MRI (3 of whom had received IV gadolinium contrast). This included patients with significant erosive changes. One patient was anti-CCP positive suggestive of RA, and two were anti-nuclear antibody positive. CONCLUSION: Imaging, and to a lesser extent serology, identified inflammatory joint pathology in a proportion of cases, providing important data to explore in a large CFA cohort examining the clinical and imaging phenotype of this group.

Is there subclinical enthesitis in early psoriatic arthritis? A clinical comparison with power doppler ultrasound.

OBJECTIVE: Enthesitis is a recognized feature of spondylarthritides (SpA), including psoriatic arthritis (PsA). Previously, ultrasound imaging has highlighted the presence of subclinical enthesitis in established SpA, but there are little data on ultrasound findings in early PsA. The aim of our study was to compare ultrasound and clinical examination (CE) for the detection of entheseal abnormalities in an early PsA cohort. METHODS: Forty-two patients with new-onset PsA and 10 control subjects underwent CE of entheses for tenderness and swelling, as well as gray-scale (GS) and power Doppler (PD) ultrasound of a standard set of entheses. Bilateral elbow lateral epicondyles, Achilles tendons, and plantar fascia were assessed by both CE and ultrasound, the latter scored using a semiquantitative (SQ) scale. Inferior patellar tendons were assessed by ultrasound alone. A GS SQ score of >1 and/or a PD score of >0 was used to describe significant ultrasound entheseal abnormality. RESULTS: A total of 24 (57.1%) of 42 patients in the PsA group and 0 (0%) of 10 controls had clinical evidence of at least 1 tender enthesis. In the PsA group, for sites assessed by both CE and ultrasound, 4% (7 of 177) of nontender entheses had a GS score >1 and/or a PD score >0 compared to 24% (9 of 37) of tender entheses. CE overestimated activity in 28 (13%) of 214 of entheses. All the nontender ultrasound-abnormal entheses were in the lower extremity. CONCLUSION: The prevalence of subclinical enthesitis in this early PsA cohort was low. CE may overestimate active enthesitis. The few subclinically inflamed entheses were in the lower extremity, where mechanical stress is likely to be more significant.

Ultrasound evaluation of fluid in knee recesses at varying degrees of flexion.

OBJECTIVE: Various methods are utilized in daily practice to obtain optimal information on effusion in the knee. Our aim is to investigate which scanning position provides the best information about synovial fluid in the knee by using ultrasound and to evaluate the magnitude of difference for measuring synovial fluid in 3 major recesses (suprapatellar, medial parapatellar, and lateral parapatellar) of the knee according to various degrees of flexion. METHODS: Sonographers in 14 European centers documented bilateral knee joint ultrasound examinations on a total of 148 knee joints. The largest sagittal diameter of fluid was measured in scans corresponding to the 3 major recesses at different (0°, 15°, 30°, 45°, 60°, and 90°) degrees of flexion of the knee. The difference of measurement of effusion according to transducer position, knee position, and the interaction between them was investigated by analysis of variance followed by Tukey's test. RESULTS: No correlation was noted between patient characteristics and ultrasound detection of effusion. The sagittal diameter of synovial fluid in all 3 recesses was greatest at 30° flexion. Analysis of variance and Tukey's test revealed that the suprapatellar scan and 30° flexion is the best combination for detecting effusion as confirmed by receiver operator characteristic curve analysis. CONCLUSION: The suprapatellar scan of the knee in 30° flexion was the most sensitive position to detect fluid in knee joints. Sagittal diameter of fluid in all 3 recesses increased with the knee in the 30° flexed position as compared to the extended position.

Which knee and probe position determines the final diagnosis of knee inflammation by ultrasound? Results from a European multicenter study.

PURPOSE: To investigate which knee and probe position best identifies knee inflammation and to determine a cut-off level for abnormal synovial effusion. MATERIALS AND METHODS: 18 experienced sonographers (all rheumatologists) performed ultrasound examinations of the knee joint in patients with knee symptoms and in healthy controls. Each sonographer performed longitudinal suprapatellar ultrasound scans using 9 different configurations at each knee: Midline, parapatallar lateral and parapatellar medial from midline in neutral position (0°) with and without quadriceps muscle contraction and in 30° flexion of the knee. The presence of synovial effusion (SE), the effusion measured in millimeters and the presence of synovial hypertrophy (SH) was noted. RESULTS: A total of 298 knees of 149 subjects (129 patients and 20 controls) were examined. The detection of SH is more sensitive and specific than the detection of SE, independently of the knee and probe position, for the final diagnosis of abnormality. The detection of both synovial hypertrophy and effusion in the knee in neutral position (0°) with quadriceps contraction and with the probe in the midline position, are the best independent predictors for knee abnormalities. Knee effusion > 3.2 mm measured with the probe in the lateral aspect of the knee is the best diagnostic characteristics for predicting pathological SE. CONCLUSION: The best combination for detecting SH and SE is obtained by placing the probe in the midline position with the knee in 0° with quadriceps contraction. A cut-off value for pathological effusion may be obtained in the lateral aspect of the knee.

Urinary type II collagen C-terminal peptide is associated with synovitis and predicts structural bone loss in very early inflammatory arthritis.

OBJECTIVES: In rheumatoid arthritis, high levels of the cartilage turnover biomarker C-terminal cross-linking telopeptide of type II collagen (CTX-II) predict an increased risk of radiological progression. In very early inflammatory arthritis erosions are uncommon, therefore CTX-II requires validation against early markers of inflammatory arthritis such as power Doppler ultrasound (PDUS) synovitis and bone mineral density (BMD) loss. METHODS: In 50 subjects with 12 weeks or less of inflammatory hand symptoms, urinary CTX-II and PDUS were performed at baseline and hand BMD at baseline and 12 months. CTX-II data were log transformed to a normal distribution. Associations between variables were examined using Pearson's r/Spearman's ρ correlations. RESULTS: The mean 12- month change in BMD was -0.0068 g/cm² and the geometric mean for baseline CTX-II/creatinine was 245.89 ng/mmol. Log-transformed baseline CTX-II showed a substantive negative association with change in average BMD over 12 months, controlling for baseline BMD and erythrocyte sedimentation rate (r=-0.359, p=0.044). The median total PDUS score was 3.0 and baseline CTX-II was significantly associated with baseline total PDUS (Spearman's ρ=0.482, p=0.002). CONCLUSION: Urinary CTX-II correlates with PDUS synovitis and hand BMD reduction very early in the course of inflammatory arthritis, suggesting that CTX-II has potential as a biomarker in very early inflammatory arthritis.

A diagnostic algorithm for persistence of very early inflammatory arthritis: the utility of power Doppler ultrasound when added to conventional assessment tools.

OBJECTIVES: The aim of this study was to assess the value of power Doppler ultrasound (PDUS) in combination with routine management in a cohort of patients with very early inflammatory arthritis (IA). METHODS: 50 patients with < or =12 weeks of inflammatory symptoms with or without signs had clinical, laboratory and imaging assessments. Diagnosis was recorded at 12 months. Assuming a 15% pre-test probability of IA, post-test probabilities for various assessments were calculated and used to develop a diagnostic algorithm. RESULTS: All patients positive for rheumatoid factor (RF) and/or cyclic citrullinated peptide (CCP) developed persistent IA, so the added value of PDUS was assessed in the seronegative (RF and CCP negative) group. The probability of IA in a seronegative patient was 6%. The addition of clinical and radiographic features raised the probability of IA to 30% and, with certain ultrasound features, this rose to 94%. CONCLUSIONS: In seronegative patients with early IA, combining PDUS with routine assessment can have a major impact on the certainty of diagnosis.

The optimal assessment of the rheumatoid arthritis hindfoot: a comparative study of clinical examination, ultrasound and high field MRI.

OBJECTIVES: The aim of this pilot study was to compare clinical examination (CE) and ultrasound (US) with high field MRI (as the reference standard) for the detection of rearfoot and midtarsal joint synovitis and secondly tenosynovitis of the ankle tendons in patients with established rheumatoid arthritis (RA). METHODS: Patients with RA (as determined by the modified American College of Rheumatology (ACR) criteria) with symptoms of midfoot and rearfoot disease were recruited. Demographic data were collected. All underwent CE, US and high field MRI (with intravenous gadolinium contrast) of their right foot. Percentage exact agreement (PEA), sensitivity and specificity were calculated for CE and US when compared to MRI. Inter-reader reliability for CE and US was also assessed. RESULTS: Compared to the gold standard of MRI, for CE (joint synovitis) the ranges for sensitivity, specificity and PEA were 55-83%, 23-46% and 46-60%, and for US were 64-89%, 60-80% and 64-78%, respectively. Compared to the gold standard of MRI, for CE (tenosynovitis) the ranges for sensitivity, specificity and PEA were 0-100%, 20-91% and 55-91%, and for US were 0-67%, 86-100% and 59-86%, respectively. CONCLUSION: CE was sensitive but US more specific in identifying hindfoot pathology in RA when compared to the reference standard of MRI. There was poor interobserver variability between ultrasonographers suggesting a need for standardisation of acquisition and interpretation of US images of the hindfoot.

Does extremity-MRI improve erosion detection in severely damaged joints? A study of long-standing rheumatoid arthritis using three imaging modalities.

BACKGROUND: Long-standing rheumatoid arthritis produces unique challenges when assessing damage due to joint deformity. The use of extremity magnetic resonance imaging (eMRI) offers the possibility of improved disease assessment because of greater patient tolerability. OBJECTIVES: The aim of this cross-sectional study was to compare the identification of wrist erosions in a severe rheumatoid arthritis cohort by eMRI with a restricted field of view (eMRI-RV) to radiography and high field MRI, using the latter as the reference. METHODS: Fifteen patients (87% female, median age 56 years) with active rheumatoid arthritis (median DAS28 7.01 and disease duration 11 years) on leflunomide were enrolled. Radiography of hands, eMRI-RV (0.2 T MagneVu MV 1000) and high field MRI of unilateral wrist joints were performed. RESULTS: Of 86 comparable wrist joint areas, high field MRI identified 70 erosions, eMRI-RV 32 and radiography 4. With high field MRI considered the reference, the sensitivity, specificity and accuracy of eMRI-RV for erosions were 46%, 94% and 55%, and the corresponding values for x ray were 6%, 100% and 23%, respectively. CONCLUSIONS: In severely damaged rheumatoid arthritis joints, sensitivity of erosion detection was markedly higher for eMRI-RV than radiography, using high field MRI as the reference. eMRI-RV was, however, less sensitive than high field MRI.