Retrospective longitudinal assessment of ultrasound gout lesions using the OMERACT semi-quantitative scoring system.

OBJECTIVES: The objectives of this study were (i) to evaluate the responsiveness of gout-specific US lesions representing urate deposition in patients receiving treat-to-target urate-lowering therapy using a binary and the OMERACT-defined semi-quantitative scoring systems; (ii) to determine the most responsive US measure for urate deposition and the optimal joint/tendon set for monitoring this. METHODS: US (28 joints, 14 tendons) was performed in microscopically verified gout patients initiating/increasing urate-lowering therapy and repeated after 6 and 12 months. Static images/videos of pathologies were stored and scored binarily and semi-quantitatively for tophus, double contour sign (DC) and aggregates. Lesion scores were calculated at patient level, as were combined crystal sum scores. Responsiveness of lesions-scored binarily and semi-quantitatively-was calculated at both patient and joint/tendon levels. RESULTS: Sixty-three patients underwent longitudinal evaluation. The static images/videos assessed retrospectively showed statistically significant decreases in tophus and DC, when scored binarily and semi-quantitatively, whereas aggregates were almost unchanged during follow-up. The responsiveness of the semi-quantitative tophus and DC sum scores were markedly higher than when using binary scoring. The most responsive measure for urate deposition was a combined semi-quantitative tophus-DC-sum score. A feasible joint/tendon set for monitoring included knee and first-second MTP joints and peroneus and distal patella tendons (all bilateral), representing the most prevalent and responsive sites. CONCLUSION: The OMERACT consensus-based semi-quantitative US gout scoring system showed longitudinal validity with both tophus and DC being highly responsive to treatment when assessed in static images/videos. A responsive US measure for urate deposition and a feasible joint/tendon set for monitoring were proposed and may prove valuable in future longitudinal studies.

Foot structure, pain and functional ability in people with gout in primary care: cross-sectional findings from the Clinical Assessment Study of the Foot.

BACKGROUND: Gout frequently affects the foot yet relatively little is known about the effects of gout on foot structure, pain and functional ability. This study aimed to describe the impact of gout in a UK primary care population. METHODS: A cross-sectional study was nested within an observational cohort study of adults aged ≥50 years with foot pain. Participants with gout were identified through their primary care medical records and each matched on age (±2 years) and gender to four participants without gout. Differences in person-level variables (SF-12 Physical Component Score, Manchester Foot Pain and Disability Index and Short Physical Performance Battery) between gout and non-gout participants were determined using regression models. Differences in foot-level variables (pain regions, skin lesions, deformities, foot posture, and non-weightbearing range of motion) were determined using multi-level regression models. All models were adjusted for body mass index. Means and probabilities with 95% confidence intervals were calculated. RESULTS: Twenty-six participants with gout were compared to 102 participants without gout (77% male; mean age 66 years, standard deviation 11). Subtalar joint inversion and eversion and 1st metatarsophalangeal joint (MTPJ) dorsiflexion range of motion were significantly lower in the gout participants compared to the non-gout participants. Gout participants were more likely to have mallet toes and less likely to have claw toes compared to non-gout participants. There were no statistically significant differences in person-level variables, foot posture, ankle dorsiflexion range of motion, hallux valgus, pain regions, or skin lesions. CONCLUSIONS: Non-weightbearing range of motion at the subtalar joint and 1st MTPJ was reduced in people with gout. Patients with gout who present with chronic foot problems should therefore undergo appropriate clinical assessment of foot structure.

An MRI assessment of chronic synovial-based inflammation in gout and its correlation with serum urate levels.

It is unclear when the synovial-based inflammatory process of gout begins. The aim of this study was to determine the percentage of patients with inter-critical gout who have chronic synovial-based inflammation as evidenced by synovial pannus on a contrast-enhanced magnetic resonance imaging (MRI) of their most involved joint and determine if the presence and/or severity correlates with their serum urate levels. All patients received a 3 T MRI of their index joint, serum urate level, CRP, and creatinine. The primary endpoint was to determine the prevalence of synovial pannus and the correlation of serum urate levels with the presence and/or severity of the synovial pannus on that same joint. MRI erosions, tophi, swelling, effusion, and osteitis were also documented. Seventy-two of 74 subjects (90% men) completed the protocol. Fifty-three of 72 (74%) index joints were the first metatarsophalangeal joint. Thirty-nine (54.2%) of the patients were on urate-lowering therapy; 15 (20.8%) and 7 (9.7%) were taking colchicine or a NSAID daily, respectively. Of the 72 subjects, 63 (87.5%) had synovial pannus on their MRI with good inter-reader agreement between the two radiologists. The mean serum urate level was 7.93 mg/dL. There was no correlation with the presence (p = 0.33) or severity (p = 0.34) of synovial pannus and serum urate levels. There was also no correlation with the presence or severity of synovial pannus and the secondary endpoints. The majority of patients with inter-critical gout have evidence of chronic synovial-based inflammation. However, the presence and severity of this inflammation do not appear to correlate with serum urate levels.

Comorbidity burden, healthcare resource utilization, and costs in chronic gout patients refractory to conventional urate-lowering therapy.

Patients with chronic gout refractory to conventional urate-lowering therapy have high rates of flares and incidence of tophi, which impose a significant disease and potentially economic burden. This study examined healthcare resource use and costs stratified by disease burden. Adult patients diagnosed with gout (ICD-9-CM:274.xx) and having had ≥3 flares defined by clinical surrogates within a 12-month period were selected for the case cohort from the Thomson MarketScan databases (2003/Q3-2008/Q3). Only patients who had received allopurinol treatment and a diagnosis of tophi (ICD-9-CM:274.8x) at any time before the first flare (index date) or within 12 months postindex were included and were matched in a 1:1 ratio with control gout-free subjects. The comorbidity burden, healthcare resource use, and annual healthcare costs (2008 US$) in the 12-month postindex period were compared between both cohorts using regression models adjusted for demographic characteristic and stratified for patients with ≥6 flares. A total of 679 gout patients met the inclusion criteria for the study and had a higher prevalence of comorbidities than their matched controls. Gout cohort had a significantly higher incidence of emergency room, hospitalizations, outpatient visits, and other medical services than did their matched controls (all comparisons, uncorrected P < 0.01). After adjusting for baseline characteristics, the refractory gout cohort incurred an incremental total annual healthcare cost of $10,222 where 40% of the annual medical cost was for gout-related care compared with control cohort (P < 0.01). Patients with refractory gout have a significant economic burden compared with a gout-free population.

Ultrasound imaging for the rheumatologist XXXVI. Sonographic assessment of the foot in gout patients.

OBJECTIVES: This study aims to investigate the relationship between clinical and US findings together with the prevalence and distribution of US findings indicative of monosodium urate (MSU) crystal deposition within the foot in patients with gout. METHODS: A total of 50 patients with gout attending the in-patient and the out-patient clinics of the Rheumatology Departments were prospectively enrolled in this multi-centre study. Multiplanar examination of the following 15 joints was performed: talo-navicular, navicular-cuneiform (medial, intermediate and lateral), calcaneo-cuboid, medial, intermediate and lateral cuneiform-metatarsal, cuboid-4th metatarsal, cuboid-5th metatarsal and all five metatarsophalangeal (MTP) joints. RESULTS: The following US findings were indicative of gout: enhancement of the superficial margin of the hyaline cartilage, intra-articular tophus, and extraarticular tophus. In 46 patients, a total of 1380 foot joints were investigated. In 1309 joints that were not clinically involved, US detected signs indicative of joint inflammation in 9% (121/1309). Talo-navicular joint and the first MTP joint were the joints in which the highest number of US findings were found at mid-foot and fore-foot, respectively. At MTP joint level, dorsal scans allowed the detection of a higher number of US findings indicative of joint inflammation, and MSU crystal deposits rather than on the volar plane. CONCLUSIONS: This study demonstrated that US detected a higher number of inflamed foot joints than clinical examination, and that the first MTP and the talo-navicular joints were the anatomic sites with the highest prevalence of US signs of MSU crystal aggregates.

Methods of tophus assessment in clinical trials of chronic gout: a systematic literature review and pictorial reference guide.

OBJECTIVE: To identify methods of tophus measurement for gout studies, summarise the properties of these methods and compile a detailed pictorial reference guide to demonstrate the methods. METHODS: A systematic search strategy for methods of tophus measurement was formulated. For each method, papers were assessed by two reviewers to summarise information according to the specific components of the Outcomes Measures in Rheumatology (OMERACT) filter: feasibility, truth and discrimination. Detailed images were obtained to construct the reference guide. RESULTS: Eight methods of tophus measurement were identified: counting the total number of tophi, physical measurement using tape measure, physical measurement using Vernier callipers, digital photography, ultrasonography (US), MRI, CT and dual energy CT. Feasibility aspects of the methods are well documented. Physical measurement techniques are more feasible than advanced imaging methods, but do not allow for assessment of intra-articular tophi or for data storage and central reading. The truth aspect of the filter has been documented for many methods, particularly Vernier callipers, US, MRI and CT. Reliability of most methods has been reported as very good or excellent. Sensitivity to change has been reported for all methods except MRI and CT. CONCLUSION: A variety of methods of tophus assessment have been described for use in clinical trials of chronic gout. Physical measurement techniques (particularly the Vernier calliper method) and US measurement of tophus size appear to meet most aspects of the OMERACT filter.

Nonsteroidal anti-inflammatory drugs and colchicine to prevent gout flare during early urate-lowering therapy: perspectives on alternative therapies and costs.

Published evidence in the literature, regulatory status, and relative costs of colchicine and nonsteroidal anti-inflammatory drugs (NSAIDs) for prophylaxis of gouty flares during early urate-lowering therapy are reviewed.

Chronic gout: epidemiology, disease progression, treatment and disease burden.

BACKGROUND: Gout is a painful and disabling inflammatory arthritis of increasing prevalence associated with hyperuricemia and the deposition of monosodium urate crystals in soft tissues and joints. Diagnosed gout cases have been estimated at 2.13% of the 2009 US population. The highest incidence occurs in the 65+ year age group, with males more than twice as likely to be afflicted as females. OBJECTIVE: To present the epidemiology of chronic gout and to discuss its disease burden. METHODS: This commentary is based on expert opinion and supplemented with published/presented information identified through PubMed and rheumatology associations. RESULTS: The steady rise of diagnosed gout cases can generally be linked to an aging population with multiple comorbidities, the use of certain prescription medications, and changes in diet and lifestyle. Progression to chronic gout has numerous causes such as poor compliance with, ineffectiveness of, or inability to tolerate prescribed regimens. Despite the availability of urate-lowering therapies (ULT), patients may either have contraindications to them or may not adequately respond. Patients with high flare frequency, tophi, and the inability to maintain serum urate levels below 6 mg/dL with ULT can be categorized as having chronic gout that is refractory, with a substantial disease burden. Based on lack of therapeutic options for urate-lowering for patients with chronic gout refractory to conventional therapy, the economic burden of this small but substantial population contributes disproportionately to the overall economic burden of chronic gout. Recent availability of gout-specific ICD-9-CM codes capturing the cost intense and impactful aspects of the disease - flares and tophi - is likely contribute to understanding the full health economic burden in gout. CONCLUSION: The impact of chronic gout, especially if refractory to treatment, on functionality, productivity, quality of life and health care costs can be substantial and is deserving of future research.

[The current role of ultrasound in the assessment of crystal-related arthropathies]. / Il ruolo attuale dell'ecografia nelle artropatie da microcristalli.

Over last few years, the ultrasonography (US) generated an increasing popularity among rheumatologists due to excellent potentiality and numerous applications in rheumatology. Most of the published papers focus mainly to demonstrate the utility of US in early and chronic arthritis, short-term therapy monitoring and guidance for invasive procedures. Less attention has been paid to the potential of this technique in the field of crystal-related arthropathies. By virtue of the high resolution of "new generation" equipments, minimal crystal deposits can be detected even sometime when the radiography was negative. The aim of this paper was to present the principal findings in patients with crystal-related arthropathies.

Severe tophaceous gout. Characterization of low socioeconomic level patients from México.

OBJECTIVE: To describe a group of patients with frequent tophaceous gout, the variables associated with severe tophaceous gout and to compare them with other patients with gout described elsewhere. METHODS: We looked for 65 demographic clinical and paraclinical variables from patients with gout who attended our gout clinic from 1995-2000 and were evaluated by the same group of physicians. RESULTS: Three hundred and sixteen patients were included, 98% males, 82% live in México city, the mean age at onset, educational level and disease duration were 37.5 +/- 12.4, 6.3 +/- 3.9 and 12.6 +/- 10.3 years respectively. Tophaceous gout was present in 62% of the patients with a mean tophi number of 4.7 +/- 6.3 and mean HAQ score 0.13 +/- 0.37. Severe tophaceous gout (>or= 5 tophi) was found in 34% and these patients had significantly: earlier age at onset, longer duration of the disease, lesser frequency of obesity and higher frequency of: intradermal tophi, HAQ > 0.5, hospitalizations, radiographic score III/IV, uric acid under-excretion, renal function impairment and previous (oral and parenteral) auto-prescribed chronic glucocorticoid treatment compared with patients with non-severe tophaceous gout. In the multiple logistic regression the significant variables were renal function impairment (p = 0.000) and previous chronic parenteral glucocorticoid treatment (p = 0.011) . CONCLUSION: Our patients compared with those from other countries who have earlier age at onset, very low frequency of gout among females, frequent tophaceous gout and severe tophaceous gout. Severe tophaceous gout in this group is associated with renal function impairment and previous chronic parenteral glucocorticoid treatment.