Ultrasound imaging for the rheumatologist. XLVII. Ultrasound of the shoulder in patients with gout and calcium pyrophosphate deposition disease

OBJECTIVES

This study was aimed at determining the prevalence of ultrasound (US) morpho-structural changes in the shoulders of patients with crystal-related arthropathies, and at investigating the relationship between them and the clinical findings.

METHODS

Eighty-eight patients with a crystal proven diagnosis of gout or calcium pyrophosphate dihydrate (CPPD) disease attending the in-patient and the out-patient clinics of four Italian Rheumatology Departments were consecutively enrolled in this multi-centre study. All patients were clinically examined by an expert rheumatologist who recorded clinical and laboratory data in addition to the presence/absence of spontaneous shoulder pain and performed the Hawkins, Jobe, Patte, Gerber, and Speed tests. In each centre, US examinations were carried out by a rheumatologist expert in musculoskeletal US blinded to clinical data, using a MyLab TWICE XVG machine (Esaote SpA, Genoa, Italy) equipped with a linear probe operating at 4-13 MHz, and a Logiq 9 machine (General Electrics Medical Systems, Milwaukee, WI, USA) with a linear probe operating at 9-14 MHz. Shoulders were scanned to detect peri-articular inflammation, rotator cuff pathology and joint involvement, and to reveal US signs indicative of crystal deposits.

RESULTS

A total of 88 patients, 39 with gout, 46 with CPPD disease, and 3 with both gout and CPPD disease, were enrolled. In total, 176 shoulders were clinically assessed, of which 54/176 (30%) were painful and 74/176 (42%) were clinically normal shoulders. All US findings indicative of peri-articular synovial inflammation were more frequently detected in patients with CPPD disease than in gouty patients. In 50 out of 176 (28.4%) shoulders, US allowed the detection of at least one finding indicative of synovial inflammation. Chronic tendinopathy was a frequent US finding both in gout patients and in patients with CPPD disease and the supraspinatus tendon was the most frequently involved one. In CPPD disease the supraspinatus tendon was found ruptured in a number of shoulders seven times higher than in gouty patients. The osteophytes were found at acromion-clavicular joint in nearly 80% of the shoulders in CPPD disease and in 60% in the gouty patients.

CONCLUSIONS

The results of this study confirm the high specificity of US findings indicative of crystal deposits at hyaline cartilage level and indicate that the supraspinatus tendon and the fibrocartilage of the acromion-clavicular joint are the most frequently affected structures of the shoulders in patients with crystal-related arthropathies.

Usability of an innovative and interactive electronic system for collection of patient-reported data in axial spondyloarthritis: comparison with the traditional paper-administered format

OBJECTIVE

To evaluate the validity, in terms of the patients' acceptance, preference, feasibility and reliability of an innovative, interactive computerized system for collection of patient-reported outcome (PRO) data on axial SpA against the paper-and-pencil version.

METHODS

Fifty-five patients with axial SpA completed both the touch screen and the paper-and-pencil set of questionnaires. A computerized touch-screen system, SPEAMonitor, was developed to capture PRO data. Variables recorded included demographic data, patient's assessment of general health status, BASDAI, BASFI, BASMI and acute-phase reactant levels. In order to assess the patient's acceptance of, preference for and feasibility of computer-based questionnaires, the participants filled in an additional questionnaire. The time taken to complete both formats was measured. In a further test-retest study, 25 patients were re-evaluated.

RESULTS

The agreement between the paper-administered and computer touch-screen format of the BASFI, BASDAI questionnaires and the Ankylosing Spondylitis Disease Activity Scores was excellent. Intraclass correlation coefficients (ICCs) between data ranged from 0.90 to 0.96. Additionally the test-retest study showed a very good agreement between the scores for the two administrations (ICC ≥ 0.90). Age, computer experience and education level had no significant impact on the results. The computerized questionnaires were reported to be easier to use. The mean time spent completing the questionnaires on a touch screen was 5.1 min and on paper 7.9 min.

CONCLUSION

Our newly developed computer-assisted touch-screen questionnaires for PRO in axial SpA were well accepted by patients, with good data quality, reliability and score agreement.

Diffusion and applications of musculoskeletal ultrasound in Italian Rheumatology Units

The Musculoskeletal Ultrasound Study Group of the Italian Society of Rheumatology (SIR) was founded during the 68th SIR Congress, on November 2011. The request of activation of this group was based on the increasing interest and the widespread diffusion of ultrasound in the scientific rheumatology community and on the solid experience of some Italian rheumatologists in the field. The aims of the Study Group are to stimulate the applications and use of ultrasound in the clinical practice at the level of the Italian rheumatology units and, in addition, to develop research projects at a national level...

Italian Society of Rheumatology recommendations for the management of gout

OBJECTIVE

Gout is the most common arthritis in adults. Despite the availability of valid therapeutic options, the management of patients with gout is still suboptimal. The Italian Society of Rheumatology (SIR) aimed to update, adapt to national contest and disseminate the 2006 EULAR recommendations for the management of gout.

METHODS

The multidisciplinary group of experts included rheumatologists, general practitioners, internists, geriatricians, nephrologists, cardiologists and evidence-based medicine experts. To maintain consistency with EULAR recommendations, a similar methodology was utilized by the Italian group. The original propositions were translated in Italian and priority research queries were identified through a Delphi consensus approach. A systematic search was conducted for selected queries. Efficacy and safety data on drugs reported in RCTs were combined in a meta-analysis where feasible. The strength of recommendation was measured by utilising the EULAR ordinal and visual analogue scales.

RESULTS

The original 12 propositions were translated and adapted to Italian context. Further evidences were collected about the role of diet in the non-pharmacological treatment of gout and the efficacy of oral corticosteroids and low-dose colchicine in the management of acute attacks. Statements concerning uricosuric treatments were withdrawn and replaced with a proposition focused on a new urate lowering agent, febuxostat. A research agenda was developed to identify topics still not adequately investigated concerning the management of gout.

CONCLUSIONS

The SIR has developed updated recommendations for the management of gout adapted to the Italian healthcare system. Their implementation in clinical practice is expected to improve the management of patients with gout.

Tips and tricks to recognize microcrystalline arthritis

US plays a useful role in diagnosing and monitoring therapy in microcrystalline arthritis, as it may detect both monosodium urate and calcium pyrophosphate crystal aggregates. The knowledge of some tips and tricks in the identification of these findings can play a key role in exploiting the relevant potential of US in microcrystalline arthritis, avoiding errors and misinterpretations. This review provides an in-depth description of simple technical and methodological issues to guide the rheumatologist in daily clinical practice.

Ultrasound imaging for the rheumatologist. XLII. Assessment of hip pain in rheumatic patients: the radiologist's view

Hip pain is a common complaint in daily practice and the identification of the underlying pathologic condition is the first step for an adequate treatment. In this review, we discuss the available evidence for the application of conventional radiography, computed tomography and magnetic resonance imaging in rheumatologic patients with painful hip, presenting the main imaging findings due to osteoarthritis, inflammatory arthritis (rheumatoid arthritis and spondyloarthritides), osteonecrosis and some other soft tissue involvement (bursitis and synovial cyst) that could be the cause of hip pain. Because different imaging techniques show different sensitivity and specificity, the choice of technique to use depends on the type and stage of the disease itself.

Ultrasound imaging for the rheumatologist XLI. Sonographic assessment of the hip in OA patients

OBJECTIVES

To investigate the prevalence of ultrasound (US) detectable abnormalities in the hip joints of patients with osteoarthritis (OA) and correlate them with clinical findings and measures of disease severity.

METHODS

Consecutive patients with hip OA were investigated by clinical and US examinations. Bilateral US of the hip joints was performed by using a Logiq9 machine, equipped with a multi-frequency linear probe, operating at 9 MHz; in addition, power Doppler (PD) was applied (frequency 7.5 MHz; PRF 750 Hz). Clinical evaluation included the registration of demographic data, disease duration, current and previous joint pain and Lequesne index. US study included the assessment of both inflammatory and structural abnormalities at the level of hip joint (joint effusion, synovial hypertrophy, local pathologic vascularisation at PD, osteophytes) and periarticular soft tissues (iliopsoas bursitis, trochanteric bursitis, iliopsoas tendinopathy, gluteus medius tendinopathy and gluteus minimus tendinopathy).

RESULTS

One hundred and fifty hips of 75 patients were studied. Clinical examination demonstrated the presence of current hip pain in 80% of patients and previous hip pain in 85.7% of cases. The mean Lequesne Index was 11.9±4.9. US detected effusion in 50% of the joints, synovial hypertrophy in 41.3%, PD signal in 0.7%, osteophytes in 77.3%; at periarticular level, trochanteric bursitis was found in 24.7% of patients, gluteus tendinopathy in 22.7%, iliopsoas tendinopathy in 7.3% and finally iliopsoas bursitis in 1.3%. The presence of current and previous hip pain significantly correlated with the presence of effusion (p=0.01); age and disease duration significantly correlated with the presence of osteophytes (p=0.01). Various US-detected abnormalities were found also in asymptomatic patients. Statistically significant differences between the 2 subgroups of symptomatic and asymptomatic patients were registered for effusion (p=0.003).

CONCLUSIONS

In hip OA, US is a useful imaging tool for analysing both inflammatory and structural damage lesions as well as for differentiating the involvement of joint structures and periarticular soft tissues. In addition, US was able to detect a wide set of abnormalities even in asymptomatic patients, confirming that it is more sensitive than clinical examination in detecting musculoskeletal involvement.

Psoriatic arthritis: need for ultrasound in everyday clinical practice

Ultrasound (US) is a rapidly evolving technique that is gaining increasing success in the assessment of psoriatic arthritis (PsA). It permits early detection and careful characterization of the inflammatory process at different tissues, which is important in diagnostic and therapeutic procedures. US presents several advantages over other imaging techniques: it is patient-friendly, safe, noninvasive, free of ionizing radiation, less expensive, and permits multiple target assessment in real time without the need for external referral. The aim of this report was to analyze the potential role of US in the assessment and management of PsA and to discuss the current evidence supporting its application in daily clinical practice.

Ultrasound in the assessment of pulmonary fibrosis in connective tissue disorders: correlation with high-resolution computed tomography

OBJECTIVE

To investigate the correlation between ultrasound (US) B-lines and high-resolution computed tomography (HRCT) findings in the assessment of pulmonary fibrosis (PF) in patients with connective tissue disorders (CTD).

METHODS

Thirty-four patients with a diagnosis of CTD were included. Each patient underwent clinical examination, pulmonary function test (PFT), chest HRCT, and lung US by an experienced radiologist or rheumatologist. A second rheumatologist carried out US examinations to assess interobserver agreement. In each patient, US B-line lung assessment including 50 intercostal spaces (IS) was performed. For the anterior and lateral chest, the IS were the second to the fifth along the parasternal, mid-clavicular, anterior axillary, and medial axillary lines (the left fifth IS of the anterior and lateral chest was not performed because of the presence of the heart, which limits lung visualization). For the posterior chest, the IS assessed were the seventh to the eighth along the posterior-axillary and subscapular lines. The second to eighth IS were assessed in the paravertebral line. In each IS, the number of US B-lines under the transducer was recorded, summed, and graded according to the following semiquantitative scoring: grade 0 = normal (< 10 B-lines); grade 1 = mild (11 to 20 B-lines); grade 2 = moderate (21 to 50 B-lines); and grade 3 = marked (> 50 B-lines).

RESULTS

A total of 1700 IS in 34 patients were assessed. A significant linear correlation was found between the US score and the HRCT score (p < 0.001; correlation coefficient ρ = 0.875). A positive correlation was found between US B-line assessments and values of DLCO (p = 0.014). Both κ values and overall percentages of interobserver agreement showed excellent agreement.

CONCLUSION

Our study demonstrates that US B-line assessment may be a useful and reliable additional imaging method in the evaluation of PF in patients with CTD.

Ultrasound imaging for the rheumatologist XL. Sonographic assessment of the hip in rheumatoid arthritis patients

OBJECTIVES

The aim of the present study was to correlate clinical and laboratory data with those obtained by ultrasound (US) evaluation of the hip in a cohort of patients with rheumatoid arthritis (RA).

METHODS

Fifty-two RA patients attending the Rheumatology Departments involved in the present study were enrolled. Demographic (age, gender), clinical (body mass index, disease duration, treatments, history or current hip pain, tenderness by internal or external hip rotation or palpation of the greater trochanteric region), laboratory (erythrosedimentation rate, C-reactive protein, rheumatoid factor and antibodies anti-citrullinated peptides) and clinimetric data (disease activity score 28 - DAS28, Health Assessment Questionnaire - HAQ, Lequesne index) were collected. All patients underwent an US examination of both hips according to international guidelines.

RESULTS

A total of 100 hips were scanned in 52 patients with RA. Approximately half of the patients reported a history of hip pain, one fourth complained of current pain, and the physical examination (internal and/or external rotation and palpation of the greater trochanteric region) evocated pain up to 19% and 22% of the patients, respectively. US examination found signs of hip joint abnormalities in 42% of the patients; US changes indicative of hip joint inflammation and damage were detected respectively in 24% and 32% of the cases. No patient presented power Doppler signal in the hip joint. A significant correlation between US pathological findings at hip level was found with clinical data (current pain and evocated pain by internal or external hip rotation). Furthermore, US cartilage lesion correlated with age of the patient, and US bone erosions with the disease duration. No correlation was found between the sonographic assessment and laboratory data, DAS 28, and Lequesne index.

CONCLUSIONS

US abnormalities at hip joint level obtained in the present study correlated with clinical findings, while no correlation was found with DAS28 or laboratory data. Further investigations are encouraged to clarify the US additional value at hip level in patients with RA.

The ability of synovitis to predict structural damage in rheumatoid arthritis: a comparative study between clinical examination and ultrasound

OBJECTIVES

To evaluate synovitis (clinical vs ultrasound (US)) to predict structural progression in rheumatoid arthritis (RA).

METHODS

Patients with RA.

STUDY DESIGN

Prospective, 2-year follow-up.

DATA COLLECTED

Synovitis (32 joints (2 wrists, 10 metacarpophalangeal, 10 proximal interphalangeal, 10 metatarsophalangeal)) at baseline and after 4 months of therapy by clinical, US grey scale (GS-US) and power doppler (PD-US); x-rays at baseline and at year 2.

ANALYSIS

Measures of association (OR) were tested between structural deterioration and the presence of baseline synovitis, or its persistence, after 4 months of therapy using generalised estimating equation analysis.

RESULTS

Structural deterioration was observed in 9% of the 1888 evaluated joints in 59 patients. Baseline synovitis increased the risk of structural progression: OR=2.01 (1.36-2.98) p<0.001 versus 1.61 (1.06-2.45) p=0.026 versus 1.75 (1.18-2.58) p=0.005 for the clinical versus US-GS versus US-PD evaluation, respectively. In the joints with normal baseline examination (clinical or US), an increased probability for structural progression in the presence of synovitis for the other modality was also observed (OR=2.16 (1.16-4.02) p=0.015 and 3.50 (1.77-6.95) p<0.001 for US-GS and US-PD and 2.79 (1.35-5.76) p=0.002) for clinical examination. Persistent (vs disappearance) synovitis after 4 months of therapy was also predictive of subsequent structural progression.

CONCLUSIONS

This study confirms the validity of synovitis for predicting subsequent structural deterioration irrespective of the modality of examination of joints, but also suggests that both clinical and ultrasonographic examinations may be relevant to optimally evaluate the risk of subsequent structural deterioration.

After treat-to-target: can a targeted ultrasound initiative improve RA outcomes?

For patients with rheumatoid arthritis (RA), remission can be achieved with tight control of inflammation and early use of disease modifying agents. The importance of remission as an outcome has been recently highlighted by European League Against Rheumatism recommendations. However, remission when defined by clinical remission criteria (disease activity score, simplified disease activity index, etc) does not always equate to the complete absence of inflammation as measured by new sensitive imaging techniques such as ultrasound (US) . There is evidence that imaging synovitis is frequently found in these patients and associated with adverse clinical and functional outcomes. This article reviews the data regarding remission, ultrasound imaging and outcomes in patients with RA to provide the background to a consensus statement from an international collaboration of ultrasonographers and rheumatologists who have recently formed a research network--the Targeted Ultrasound Initiative (TUI) group. The statement proposes that targeting therapy to PD activity provides superior outcomes compared with treating to clinical targets alone and introduces the rationale for a new randomised trial using targeted ultrasound in RA.

Ultrasound imaging for the rheumatologist XXXIX. Sonographic assessment of the hip in fibromyalgia patients

Fibromyalgia syndrome (FMS) is a common form of non-inflammatory rheumatism within the general population with symptoms often mimicking those of arthritis or muscle disorders. Arthralgic symptoms in the region of the hip are commonly mentioned by patients with FMS and one of the diagnostic trigger points for the condition is found around the greater trochanter. To date, no formal imaging studies using ultrasound (US) have been performed in FMS. This study describes the correlation between clinical and US findings in patients presenting with primary FMS to rheumatology clinics. In the majority of the patients, no significant pathological US abnormalities were detected.

Interreader reliability in assessment of nailfold capillary abnormalities by beginners: pilot study of an intensive videocapillaroscopy training program

OBJECTIVE

To test the learning curve of rheumatologists with different experience in videocapillaroscopy (VCP) attending an intensive training program focused on interpretation of the main capillary nailfold abnormalities, the scleroderma (systemic sclerosis, SSc) pattern, and the normal pattern, and to determine their interreader agreement with an experienced investigator.

METHODS

Five investigators (1 senior, 1 junior, and 3 beginners) participated in the exercise. The study was composed of 2 steps. First, an independent investigator selected representative VCP images of normal patterns and capillary abnormalities. The second step included the training program, which ran 4 hours per day for 7 days. The senior rheumatologist taught investigators to recognize and interpret the normal pattern, the capillary abnormalities, and the different types of SSc pattern. These abnormalities were considered: homogeneously enlarged capillaries, giant capillaries, irregularly enlarged capillaries, microhemorrhages, neoangiogenesis, avascular areas, and capillary density.

RESULTS

A total of 300 VCP images were read from all the investigators. Both κ values and overall agreement percentages of qualitative and quantitative assessments showed progressive improvement from poor to excellent from the beginning to the end of the exercise. The sensitivity and specificity of the participants in the assessment of SSc pattern at the last lecture session were high.

CONCLUSION

Our pilot study suggests that after an intensive 1-week training program, novice investigators with little or no experience in VCP are able to interpret the main capillary abnormalities and SSc pattern and to achieve good interreader agreement rates.

CS injection of tenosynovitis in patients with chronic inflammatory arthritis: the role of US

OBJECTIVE

The main aim of this study was to investigate the short-term efficacy of CS loco-regional treatment performed under US guidance in tenosynovitis of patients with chronic inflammatory arthritis.

METHODS

Thirty consecutive patients affected by chronic arthritis and with clinical suspicion of tenosynovitis were recruited to undergo US assessment. In the sonographically proven cases, US-guided CS injection was performed. A visual analogue scale for pain (ranging from 0 to 10) and a tenderness score (ranging from 0 to 3) were used for the clinical evaluation. Sonographic pathological findings indicative of tenosynovitis were scored using a semi-quantitative 4-grade scoring system, for both grey-scale and power Doppler US, at baseline and during a follow-up visit at 2 weeks after the CS injection.

RESULTS

In 21 (70%) of 30 patients, the clinical suspicion of tenosynovitis was confirmed (9 with RA, 11 with PsA and 1 with ReA). In the other nine patients, US revealed synovitis of the adjacent joints, bursitis, oedema of the s.c. tissue or a partial tear. In all cases the appropriate needle placement and subsequent CS injection into the tendon sheath were obtained with US confirmation. A significant reduction in all clinical and sonographic scorings was found during the follow-up visit.

CONCLUSIONS

The present study shows the efficacy of US-guided peritendinous CS injections in the management of patients with chronic inflammatory arthritis presenting as US-proven tenosynovitis.

Ultrasound imaging for the rheumatologist XXXVIII. Sonographic assessment of the hip in psoriatic arthritis patients

OBJECTIVES

The aims of our study were to investigate the prevalence of ultrasound (US) pathological abnormalities in the hip of psoriatic arthritis (PsA) patients and compare them with the clinical findings.

METHODS

Sixty-five PsA patients were enrolled in the study. Bilateral examination of the hip was performed to detect joint effusion, synovial hypertrophy, irregularity of femoral head and neck profile as seen in erosions and/or osteophytes.

RESULTS

Joint effusion was detected in 20 out of 130 hips (15%). Synovial hypertrophy was present in 12 out of 20 hips (60%) associated with effusion (9.3% of all hip joints) and only 1 of them showed PD signal. Small effusion without synovial proliferation was imaged in 8 out of 20 hips (40%). On the whole 14 out of 65 patients (21%) had joint effusion with or without synovial hypertrophy using US. No erosions of the femoral head and neck profile were detected whilst osteophytes were imaged in 27 joints (20%). No US abnormalities were demonstrated in 18 hips with pain/tenderness on physical examination, whilst joint effusion was seen in 8 joints which were asymptomatic.

CONCLUSIONS

US is a useful imaging method to evaluate hip involvement in PsA that could be integrated into routine PsA management even if patients do not complain of hip involvement.

Different microvascular involvement in dermatomyositis and systemic sclerosis. A preliminary study by a tight videocapillaroscopic assessment

OBJECTIVES

To observe for changes in capillary morphology and architecture by tight sequential videocapillaroscopic (VCP) assessment in patients with dermatomyositis (DM) and systemic sclerosis (SSc).

METHODS

VCP examination was performed in 6 patients with DM and 9 with SSc, at baseline and after one month for three times. Four consecutive fields were examined bilaterally for any single finger (from 2nd to 5th). The best visible image per each digit was selected and images from baseline and follow-up were analysed as a sequence, to allow the same capillaries to be tracked and re-assessed. The following abnormalities were identified: homogeneous enlarged capillaries, giant capillaries, irregularly enlarged capillaries, microhaemorrhages, microaneurysms and neoangiogenesis. Capillary density was also considered.

RESULTS

A significant progressive change of the following abnormalities was detected in DM patients with respect to SSc patients: microhaemorrhages (p=0.009), avascular areas (p=0.024), neoangiogenesis (p=0.001), microaneurysms (0.001), and irregular enlarged capillaries (p=0.044). No significant differences were found for homogeneous enlarged capillaries (p=0.140), giant capillaries (p=1.0) and hairpin/crossed capillaries (0.516).

CONCLUSIONS

Our preliminary study demonstrated a rapid change of the capillary morphology and architecture in DM with respect to SSc patients. Additional investigations involving larger series of patients may be useful to support more strongly our observations.

Development of a preliminary US power Doppler composite score for monitoring treatment in PsA

OBJECTIVE

To develop a preliminary power Doppler (PD) US composite score for global assessment of PsA patients.

METHODS

Sixteen PsA patients receiving anti-TNF-α therapy were enrolled. All patients were involved in multiple psoriatic targets, including joints, tendon, enthesis, skin and nail. The target with the highest PD signal, one for each target area, was selected to be scanned at baseline and at follow-up visit 8 weeks after. For each target, PD was graded according to semi-quantitative scoring systems. Inter- and intra-observer reliability and feasibility was also investigated. The new PD composite score for PsA was called Five Targets PD for Psoriatic Disease (5TPD).

RESULTS

Sixty targets (16 joints, 9 tendons, 11 enthesis, 16 psoriatic plaques and 8 psoriatic onychopathies) were assessed. A significant improvement of the clinical scores was found at follow-up with respect to the baseline: HAQ modified for SpA (HAQ-S) (P = 0.0001); Psoriasis Area and Severity Index (P = 0.0001) and Nail Psoriasis Severity Index (P = 0.35). The 5TPD showed a significant change between baseline and follow-up (P = 0.0001). There was no significant correlation between HAQ-S and 5TPD findings. The inter- and intra-observer κ-values varied from good to excellent at baseline and follow-up. The time spent on baseline US examinations was mean (s.d.) 10.5 (2.0) min and no more than 7 min for follow-up assessment.

CONCLUSION

The present study provides a new working hypothesis that the sonographic core set may be useful to construct a PDUS composite score for the assessment of PsA. The 5TPD formula provides a feasible and reliable approach for multi-target monitoring of psoriatic disease.

Clinical features of gout

Gout is a metabolic disease characterized by hyperuricemia and the deposition of monosodium urate (MSU) crystals in the joints and soft tissues, consisting of a self-limited acute phase characterized by recurrent attacks of synovitis and a chronic phase in which inflammatory and structural changes of the joints and periarticular tissues may lead to persistent symptoms. Acute gout is characterized by a sudden monoarthritis of rapid onset, with intense pain, mostly affecting the big toe (50% of initial attacks), the foot, ankle, midtarsal, knee, wrist, finger, and elbow. Acute flares also occur in periarticular structures, including bursae and tendons. The presence of characteristic MSU crystals in the joint fluid, appearing needle-like and showing strong negative birefringence by polarized microscopy, is pivotal to confirm the diagnosis of gout. The time interval separating the first attack from subsequent episodes of acute synovitis may be widely variable, ranging from a few days to several years. During the period between acute attacks the patient is asymptomatic even if MSU deposition may continue to increase silently. The factors that control the rate, location, and degree of ongoing deposition in gouty patients are not well defined. Chronic gout is the natural evolution of untreated hyperuricemia in patients with gouty attacks followed by pain-free intercritical periods. It is characterized by the deposition of solid MSU crystal aggregates in a variety of tissues including joints, bursae and tendons. Tophi can occur in a variety of locations including the helix of the ear, olecranon bursa, and over the interphalangeal joints. Their development is usually related with both the degree and the duration of hyperuricemia. About 20% of patients with gout have urinary tract stones and can develop an interstitial urate nephropathy. There is a strong association between hyperuricaemia and the metabolic syndrome (the constellation of insulin resistance, hypertension, obesity and dyslipidaemia), and gouty patients often have a medical history of kidney disease, diabetes mellitus and signs of vascular illness such as coronary artery disease, heart failure and stroke, resulting with a poor overall quality of life.

Ultrasound imaging for the rheumatologist XXXVII. Sonographic assessment of the hip in ankylosing spondylitis patients

OBJECTIVES

To investigate the prevalence of ultrasound (US) detectable inflammation in hips of patients with ankylosing spondylitis (AS) and the relationship between US and measures of disease activity and severity.

METHODS

Consecutive patients with AS attending the rheumatology units involved in this study were enrolled. Clinical and demographical data were recorded. US examination of bilateral hips was performed at the same time, evaluating anterior longitudinal scan to search for synovial hypertrophy (SH), joint effusion (JE) or power Doppler (PD) positive synovitis.

RESULTS

A total of 56 patients were included, median age (interquartile range, IQR) 49 (39, 59.5), median disease duration 98 (72, 204) months, 80.3% were treated with TNF-α inhibitors, median BASDAI 2.65 (1.96, 3.95), 30.3% had hip tenderness. US JE was found in 26.7% of patients, US SH in 16%, no patient had detectable PD. The concordance between clinical findings and US abnormalities was moderate, with a kappa of 0.44. Patients with detectable US abnormalities had higher median visual analogue scale (VAS) pain and C-reactive protein (CRP), while there was no significant association with other measures of disease activity and disability. In the subgroup of patients with no hip tenderness, US alterations were still significantly related to higher CRP levels, while in patients with hip tenderness and no US abnormalities CRP was not higher than in the asymptomatic patients.

CONCLUSIONS

US assessment of hip joint in AS patients can be considered of value, as suggested by the correlation with relevant clinical and laboratory measures. In asymptomatic patients, US examination might provide further information on subclinical involvement.