Seasonal Variations and Associated Factors of Gout Attacks: a Prospective Multicenter Study in Korea.

BACKGROUND: We purposed to evaluate the seasonality and associated factors of the incidence of gout attacks in Korea. METHODS: We prospectively enrolled patients with gout attacks who were treated at nine rheumatology clinics between January 2015 and July 2018 and followed them for 1-year. Demographic data, clinical and laboratory features, and meteorological data including seasonality were collected. RESULTS: Two hundred-five patients (men, 94.1%) were enrolled. The proportion of patients with initial gout attacks was 46.8% (n = 96). The median age, body mass index, attack duration, and serum uric acid level at enrollment were 50.0 years, 25.4, 5.0 days, and 7.4 mg/dL, respectively. Gout attacks were most common during spring (43.4%, P < 0.001) and in March (23.4%, P < 0.001). A similar pattern of seasonality was observed in the group with initial gout attacks. Alcohol was the most common provoking factor (39.0%), particularly during summer (50.0%). The median diurnal temperature change on the day of the attack was highest in the spring (9.8°C), followed by winter (9.3°C), fall (8.6°C), and summer (7.1°C) (P = 0.027). The median change in humidity between the 2 consecutive days (the day before and the day of the attack) was significantly different among the seasons (3.0%, spring; 0.3%, summer; -0.9%, fall; -1.2%, winter; P = 0.015). One hundred twenty-five (61%) patients completed 1-year follow-up (51% in the initial attack group). During the follow-up period, 64 gout flares developed (21 in the initial attack group). No significant seasonal variation in the follow-up flares was found. CONCLUSION: In this prospective study, the most common season and month of gout attacks in Korea are spring and March, respectively. Alcohol is the most common provoking factor, particularly during summer. Diurnal temperature changes on the day of the attack and humidity changes from the day before the attack to the day of the attack are associated with gout attack in our cohort.

Clinical outcomes of patients with active rheumatoid arthritis with normal acute phase reactant values.

AIM: Despite high clinical disease activity, some patients with active rheumatoid arthritis (RA) have normal acute phase reactant (APR) values. This study aimed to determine the clinical outcomes of active RA patients with normal APR values. METHOD: Of 5376 patients with RA enrolled in the Korean observational study network for arthritis (KORONA) registry, 400 patients with disease duration of <2 years who had Clinical Disease Activity Index (CDAI) score of >2.8 at baseline, biologic-naïve, and erythrocyte sedimentation rate (ESR) and C-reactive protein (CRP) drawn at both baseline and 2-year follow-up visits were identified. Patients were grouped according to baseline APR levels: normal APRs, one APR elevated, and both APRs elevated. RESULTS: Baseline tender and swollen joint counts, mean CDAI and Health Assessment Questionnaire-Disability Index (HAQ-DI) scores were significantly lower in the normal APRs group compared with APR-elevated groups (P < 0.0001). At 2-year follow-up, mean CDAI scores, HAQ-DI, and percentage of the patient achieving remission were not significantly different between the normal APRs group compared with the APR-elevated groups regardless of the baseline disease activity. However, in patients with baseline CDAI moderate to high disease activity, the normal APRs group less frequently required initiation of the biologic disease-modifying anti-rheumatic drugs compared with the APR-elevated groups (P = 0.044). CONCLUSION: Active RA patients with normal APR values have milder disease presentation, but similar clinical outcomes to those with elevated APRs.

Associations between trabecular bone score and vertebral fractures in patients with axial spondyloarthritis.

OBJECTIVES: To compare trabecular bone scores (TBS) between axial SpA (axSpA) patients with and without vertebral fractures and investigate associations between TBS and vertebral fractures. METHODS: Two hundred and fifty-five patients fulfilling the imaging arm of the Assessment of SpondyloArthritis International Society axSpA criteria were enrolled. TBS and BMD were assessed using dual-energy X-ray absorptiometry. Vertebral fracture of the thoracic and lumbar spine was defined according to the Genant criteria. Osteoporosis risk factors, inflammatory markers, DAS and spinal structural damage were also assessed. Univariate logistic regression analysis was performed to identify factors associated with vertebral fractures. RESULTS: There were 31 vertebral fractures in 28/255 axSpA patients (11%). The mean (s.d.) TBS was 1.39 (0.11) and 1.30 (0.13) in patients without and with vertebral fractures, respectively (P < 0.001). BMD in the femoral neck was lower in patients with vertebral fractures (P = 0.027), but BMDs in the lumbar spine and total hip were not. Univariate logistic regression analyses identified old age (⩾50 years), TNF inhibitor treatment, the presence of syndesmophytes and a low TBS (<1.23) as associated with prevalent vertebral fractures [odds ratio (95% CI): 6.9 (2.0, 24.4), 2.4 (1.0, 5.5), 5.5 (2.2, 13.5) and 5.3 (2.0, 14.1), respectively]. TBS has a better discriminatory value than BMD at the total hip for prediction of vertebral fractures in axSpA patients (P = 0.034). CONCLUSION: Similar to individuals with primary osteoporosis, axSpA patients with vertebral fractures have a lower TBS. This suggests that TBS has the potential to predict future vertebral fractures in patients with axSpA.

Low Skeletal Muscle Mass is Associated with the Risk of Low Bone Mineral Density in Urban Dwelling Premenopausal Women.

To evaluate the relationship between skeletal muscle mass and bone mineral density (BMD) and to determine the association between low skeletal muscle mass and low BMD in urban dwelling young adults. This study was based on data from the 2008-2011 Korea National Health and Nutrition Examination Surveys. The subjects were 1702 20-49-year-old men and 2192 premenopausal women (age 20-55 years). BMD at the lumbar spine, femoral neck, and total hip and the appendicular skeletal muscle mass (ASM) were measured by dual-energy X-ray absorptiometry. Skeletal muscle mass index (SMI) was defined as weight-adjusted ASM. Mildly and severely low muscle skeletal mass were defined as SMI that was 1-2 and >2 standard deviations below the sex-specific mean ASM of young adults, respectively. Low BMD was defined as T score of less than -1.0 at the lumbar spine, femoral neck, and/or total hip. After adjusting for confounders, skeletal muscle mass was positively associated with BMD at the lumbar spine, femoral neck, and total hip in both men and women. Mildly and severely low skeletal muscle mass increased the risk of low BMD in premenopausal women [OR (95% CI) = 1.4 (1.1-1.9) and 2.4 (1.2-4.6), respectively] but not men. In women, low skeletal muscle mass independently was associated with the risk of low BMD at the femoral neck and total hip but not the lumbar spine. Skeletal muscle mass was independently associated with BMD in urban dwelling young men and women, but low skeletal muscle mass was associated with the risk of low BMD in premenopausal women only.

A Case of Rheumatoid Vasculitis Involving Hepatic Artery in Early Rheumatoid Arthritis.

Rheumatoid vasculitis is a rare, but most serious extra-articular complications of long-standing, seropositive rheumatoid arthritis (RA). Vasculitis of hepatic artery is an extremely rare but severe manifestation of rheumatoid vasculitis. A 72-year-old woman who presented with polyarthralgia for 2 months was diagnosed with early RA. Since she had manifestations of livedo reticularis, and liver dysfunction which was atypical for RA patients, a percutaneous needle liver biopsy was performed revealing arteritis of a medium-sized hepatic artery. Extensive investigations did not reveal evidences of other systemic causes such as malignancy or systemic vasculitis. The patient was diagnosed with rheumatoid vasculitis involving hepatic arteries based on Bacon and Scott criteria for rheumatoid vasculitis. With high dose corticosteroid and cyclophosphamide induction and methotrexate and tacrolimus maintenance treatment, she was successfully recovered. Association of rheumatoid vasculitis at very early stages of the disease may represent an early aggressive form of RA.

Impact of Childbearing Decisions on Family Size of Korean Women with Systemic Lupus Erythematosus.

Systemic lupus erythematosus (SLE) predominantly affects women in their reproductive years and has a significant impact on childbearing. We investigated the influence of personal decision on family size among Korean women with SLE and factors that affect the decisions. A case-control study comparing childbearing history and decisions of 112 SLE patients and 135 controls was performed. Women with SLE participating in the Network for Lupus Clinical Research in South Korea and matching controls between ages of 18-45, who are/were married or living with a partner were included. Data regarding socio-demographics, reproductive history, and childbearing decisions were collected through a survey using a standardized questionnaire and medical record review. More women with SLE reported at least one pregnancy (85.7% vs. 71.9%, P = 0.009) or at least one live birth (85.7% vs. 71.9%, P = 0.003) compared with controls. Mean number of pregnancies was significantly higher (2.4 ± 1.6 vs. 1.4 ± 1.3, P < 0.001), and mean number of live births was significantly lower in women with SLE (1.2 ± 0.8 vs. 1.6 ± 0.8, P < 0.001). Significantly more women with SLE made the decision not to have children compared with controls (54.5% vs. 40.7%, P = 0.031), and health-related concerns were the major cause of the decision. Other socio-demographic factors did not influence the decision to limit childbearing in SLE women. The disease-related concerns had significant impact on family size and childbearing decisions among Korean women with SLE.

The prevalence of periarticular lesions detected on magnetic resonance imaging in middle-aged and elderly persons: a cross-sectional study.

BACKGROUND: Previous studies showed that among persons with radiographic knee OA, periarticular lesions were significantly more common among participants with knee pain than those without. However, data were derived mostly from persons with knee OA, and there were few normal participants without knee OA in the data analyses. The objectives of this study were to investigate the prevalence of periarticular lesions detected by magnetic resonance imaging (MRI), and to examine their prevalence according to the presence of knee pain and radiographic knee osteoarthritis (OA) in community residents in Korea. METHODS: Demographic and knee pain data were obtained by questionnaire from 358 participants of the population-based Hallym Aging Study who were recruited irrespective of the presence of knee OA or pain. Radiographic evaluations consisted of weight-bearing knee anteroposterior radiographs and 1.5-T MRI scans. Periarticular lesions included prepatellar or anserine bursitis, Baker's cyst, and tibiofibular cyst. The prevalence of each lesion in subjects with knee OA or knee pain compared to those without was examined by a chi-square test. RESULTS: The mean age of the subjects was 72 years and 50.6% were female. Radiographic knee OA was present in 34.5%. The most prevalent peri-articular lesion was Baker's cyst (27.9%), followed by tibiofibular cyst (9.5%). Anserine bursitis and tibulofibular cyst were more common in subjects with knee OA (17.5% vs 2.2% for anserine bursitis, 15.8% vs 6.1% for tibiofibular cyst in subjects with and without OA, respectively), while Baker's cyst and anserine bursitis were more common in subjects with knee pain (36.3% vs 21.8% for Baker's cyst, 14.4% vs 2.5% for anserine bursitis in subjects with and without knee pain, respectively). CONCLUSIONS: Periarticular lesions on MRI of the knee are common in middle-aged and elderly persons. Anserine bursitis and Baker's cysts are more common in subjects with knee pain compared to those without.

Fat Metaplasia on Sacroiliac Joint Magnetic Resonance Imaging at Baseline Is Associated with Spinal Radiographic Progression in Patients with Axial Spondyloarthritis.

OBJECTIVE: To study the relationship between inflammatory and structural lesions in the sacroiliac joints (SIJs) on MRI and spinal progression observed on conventional radiographs in patients with axial spondyloarthritis (axSpA). METHODS: One hundred and ten patients who fulfilled the ASAS axSpA criteria were enrolled. All underwent SIJ MRI at baseline and lumbar spine radiographs at baseline and after 2 years. Inflammatory and structural lesions on SIJ MRI were scored using the SPondyloArthritis Research Consortium of Canada (SPARCC) method. Spinal radiographs were scored using the Stoke AS Spinal Score (SASSS). Multivariate logistic regression analysis was performed to identify predictors of spinal progression. RESULTS: Among the 110 patients, 25 (23%) showed significant radiographic progression (change of SASSS≥2) over 2 years. There was no change in the SASSS over 2 years according to the type of inflammatory lesion. Patients with fat metaplasia or ankyloses on baseline MRI showed a significantly higher SASSS at 2 years than those without (p<0.001). According to univariate logistic regression analysis, age at diagnosis, HLA-B27 positivity, the presence of fat metaplasia, erosion, and ankyloses on SIJ MRI, increased baseline CRP levels, and the presence of syndesmophytes at baseline were associated with spinal progression over 2 years. Multivariate analysis identified syndesmophytes and severe fat metaplasia on baseline SIJ MRI as predictive of spinal radiographic progression (OR, 14.74 and 5.66, respectively). CONCLUSION: Inflammatory lesions in the SIJs on baseline MRI were not associated with spinal radiographic progression. However, fat metaplasia at baseline was significantly associated with spinal progression after 2 years.

Autoregulatory function of interleukin-10-producing pre-naïve B cells is defective in systemic lupus erythematosus.

INTRODUCTION: Pre-naïve B cells represent an intermediate stage in human B-cell development with some functions of mature cells, but their involvement in immune responses is unknown. The aim of this study was to determine the functional role of normal pre-naïve B cells during immune responses and possible abnormalities in systemic lupus erythematosus (SLE) that might contribute to disease pathogenesis. METHODS: Pre-naïve, naïve, and memory B cells from healthy individuals and SLE patients were stimulated through CD40 and were analyzed for interleukin-10 (IL-10) production and co-stimulatory molecule expression and their regulation of T-cell activation. Autoreactivity of antibodies produced by pre-naïve B cells was tested by measuring immunoglobulin M (IgM) autoantibodies in culture supernatants after differentiation. RESULTS: CD40-stimulated pre-naïve B cells produce larger amounts of IL-10 but did not suppress CD4(+) T-cell cytokine production. Activated pre-naïve B cells demonstrated IL-10-mediated ineffective promotion of CD4(+) T-cell proliferation and induction of CD4(+)FoxP3(+) T cells and IL-10 independent impairment of co-stimulatory molecule expression and tumor necrosis factor-alpha (TNF-α) and IL-6 production. IgM antibodies produced by differentiated pre-naïve B cells were reactive to single-stranded deoxyribonucleic acid. SLE pre-naïve B cells were defective in producing IL-10, and co-stimulatory molecule expression was enhanced, resulting in promotion of robust CD4(+) T-cell proliferation. CONCLUSIONS: There is an inherent and IL-10-mediated mechanism that limits the capacity of normal pre-naïve B cells from participating in cellular immune response, but these cells can differentiate into autoantibody-secreting plasma cells. In SLE, defects in IL-10 secretion permit pre-naïve B cells to promote CD4(+) T-cell activation and may thereby enhance the development of autoimmunity.

Peripheral immature B cells: modulators of autoimmunity.

B cells play an essential role in humoral immunity by producing antigen-specific antibodies. However, B cells also participate in cellular immune responses by presenting antigens, providing costimulation, and producing cytokines to activate and expand effectors and memory T cell populations. Recent identification of antibody-independent functions of B cells has reawakened interest in the many roles of B cells in normal immune responses as well as in autoimmune diseases. B cells interact with other immunocompetent cells during a tightly regulated immune activation process, acting as both effector and regulator. If this balance between effector and regulatory B cell functions is disrupted, harmful effects of immune activation such as autoimmunity can occur. In this review, we will discuss the role of human peripheral immature B cells in normal immune responses as a modulator of autoimmunity. We will also discuss abnormalities of these cells in pathogenesis of systemic autoimmunity with particular focus on systemic lupus erythematosus pathogenesis.

HOXB13 regulates the prostate-derived Ets factor: implications for prostate cancer cell invasion.

HOXB13 has been shown to enhance the invasive potential of breast and endometrial tumors. HOXB13 is also abundant in castration-resistant prostate tumors. To determine the invasive potential of HOXB13 in prostate tumors, highly metastatic PC3 prostate cancer cells were manipulated to express HOXB13 and/or the prostate-derived Ets factor (PDEF). The PDEF is believed to reduce the invasive potential of various tumors, including prostate tumors. To further demonstrate the functional correlation between HOXB13 and PDEF, transwell invasion and gelatin zymography assays were performed. In addition, the western blot analysis was used to demonstrate the expression of PDEF target proteins involved in cancer cell migration and invasion, MMP-9 and survivin. According to the results, HOXB13 promoted PC3 cell migration and invasion. The DNA microarray analysis demonstrated that HOXB13 significantly suppressed the expression of the PDEF. Accordingly, the expression of MMP-9 and survivin was regulated by HOXB13. In addition, HOXB13 promoted the invasive potential of PC3 cells while inhibiting the PDEF. The coexpression of HOXB13 and the PDEF led to moderate retardation of the number of invasive cells, indicating that HOXB13 functionally counteracted cell invasion by reducing PDEF expression. The western blot analysis demonstrated that HOXB13 counteracted the PDEF-mediated inhibition of the expression of PDEF target proteins such as MMP-9 and survivin. The results suggest that the HOXB13-mediated promotion of tumor cell invasion is accomplished mainly through the downregulation of PDEF expression.

Incidence and predictors of morphometric vertebral fractures in patients with ankylosing spondylitis.

INTRODUCTION: Ankylosing spondylitis (AS) is associated with an increased incidence of vertebral fractures (VFs); however the actual incidence and predictors of morphometric VFs are unknown. The present study examined the incidence and predictors of new VFs in a large AS cohort. METHODS: In total, 298 AS patients who fulfilled the modified New York criteria were enrolled and spinal radiographs were evaluated biennially. Clinical and laboratory data and radiographic progression were assessed according to the Bath AS Disease Activity Index, erythrocyte sedimentation rate, C-reactive protein (CRP), and the Stoke AS spine score (SASSS). VF was defined according to the Genant criteria. The incidence of VFs at 2 and 4 years was evaluated using the Kaplan-Meier method. The age-specific standardized prevalence ratio (SPR) for AS patients in comparison with the general population was calculated. RESULTS: Of 298 patients, 31 (10.8%) had previous VFs at baseline. A total of 30 new VFs occurred in 26 patients over 4 years. The incidence of morphometric VFs was 4.7% at 2 years and 13.6% at 4 years. Multivariate logistic regression analysis showed that previous VFs at baseline and increased CRP levels at 2 years were predictors of new VFs (odds ratio (OR) =12.8, 95% confidence interval (CI) = 3.6-45.3 and OR = 5.4, 95% CI = 1.4-15.9). The age-specific specific standardized prevalence ratio of morphometric VFs in AS was 3.3 (95% CI 2.1-4.5). CONCLUSIONS: The incidence of morphometric VFs increased in AS. Previous VFs and increased CRP levels predicted future VFs. Further studies are needed to identify the effects of treatment interventions on the prevention of new VFs.

Prevalence of systemic lupus erythematosus in South Korea: an administrative database study.

BACKGROUND: Systemic lupus erythematosus (SLE) is a rare autoimmune disease for which a population-based survey on the prevalence of the disease in South Korea has not yet been conducted. Our goal was to estimate the nationwide prevalence of SLE. METHODS: The International Classification of Diseases, Tenth Revision (ICD-10) code for SLE diagnosis-M32-was tentatively given when patients were suspected to have SLE before 2009. As such, the positive predictive value (PPV) of the M32 code shown in medical bills reflecting true SLE was uncertain. We attempted to estimate the prevalence of SLE in South Korea using national administrative database data from 2004-2006. We approximated the actual number of SLE patients by analyzing a list of SLE-coded patients provided by the National Health Insurance (NHI) and Health Insurance Review and Assessment Service. Prevalence was estimated by multiplying the PPV of the M32 diagnostic code by the number of patients receiving the code. The PPV was determined by three methods: direct investigation of the medical records of patients randomly selected from the SLE-coded patients list; assessment of all SLE patients treated at 56 selected hospitals in South Korea; and extrapolation from sub-groups at a single institute to the sub-groups of the national NHI data. RESULTS: The estimated number of national SLE cases was between 9000 and 11,000, depending on the method of ascertainment, corresponding to a prevalence of 18.8-21.7 per 100,000 people. CONCLUSIONS: This is the first report of a nationwide prevalence survey of SLE in South Korea. National databases may serve as a resource for epidemiologic studies of rare autoimmune diseases like SLE.

Metformin downregulates Th17 cells differentiation and attenuates murine autoimmune arthritis.

INTRODUCTION: This study was undertaken to determine whether metformin has anti-inflammatory effects in the collagen antibody-induced arthritis (CAIA) murine model. The effect of metformin on Th17 cell differentiation was also investigated. METHODS: CAIA mice were treated with 100 and 150 mg/kg i.p. metformin (low- and high-dose groups, respectively). Arthritis activity and histological joint destruction were studied. Flow cytometry was used to (i) determine RORγt-expressing CD4+ percentages in draining axillary lymph nodes (ALNs) from metformin-treated and untreated mice with CAIA, (ii) determine Th17 percentages in splenic CD4+ T cells cultured ex vivo for 3 days in Th17-differentiation-inducing conditions, and (iii) determine the percentages of RORγt+CD4+ T cells when normal splenic T cells from DBA/1 mice were cultured in Th17-differentiation-inducing conditions together with various metformin doses. Western blot analysis was used to assess the intracellular signaling of the metformin-treated splenocytes. RESULTS: Metformin attenuated both arthritis scores and bone destruction in CAIA mice, decreased the serum levels of the pro-inflammatory cytokines, TNF-α and IL-1, and reduced the number of RORγt+CD4+ T cells in the ALNs. Splenocytes from metformin-treated CAIA mice differentiated less readily into Th17 cells upon ex vivo stimulation. Metformin treatment of normal cells cultured in Th17-differentiation-inducing conditions decreased the number of RORγt-expressing CD4+ cells in a dose-dependent manner and downregulated STAT3 phosphorylation via the AMPK pathway. CONCLUSIONS: Metformin had an anti-inflammatory effect on murine autoimmune arthritis due to the inhibition of Th17 cell differentiation. Metformin may have a possible therapeutic value for treatment of rheumatoid arthritis.

Prevalence of knee pain and its influence on quality of life and physical function in the Korean elderly population: a community based cross-sectional study.

To investigate the prevalence of knee pain and its influence on physical function and quality of life (QOL), we examined 504 community residents of Chuncheon, aged ≥ 50 yr. Demographic information was obtained by questionnaire, and radiographic evaluations consisted of weight-bearing semi-flexed knee anteroposterior radiographs. Self-reported QOL and function were assessed using the Western Ontario and McMaster Universities Osteoarthritis (WOMAC) Index and Short Form 12 (SF-12). Performance-based lower extremity function was assessed using the tests consisting of standing balance, usual walk and chair stands. The prevalence of knee pain was 46.2% (32.2% in men and 58.0% in women) and increased with age in women. After adjustment of confounders including the presence of knee OA, the subjects with knee pain had significantly worse WOMAC function and SF-12 scores compared to subjects without knee pain. Among the subjects with knee pain, women had worse WOMAC and SF-12 scores than men. Subjects with knee pain had worse physical performance score compared to those without knee pain, especially among females. In conclusion, the prevalence of knee pain is high (32.2% in men and 58.0% in women) in this elderly community population in Korea. Independent of knee OA and other confounding factors, subjects with knee pain have more than 5-fold increase in the risk of belonging to the worst lower extremity function compared to subjects without knee pain.

HOXB13 is co-localized with androgen receptor to suppress androgen-stimulated prostate-specific antigen expression.

During the prostate cancer (PCa) development and its progression into hormone independency, androgen receptor (AR) signals play a central role by triggering the regulation of target genes, including prostate-specific antigen. However, the regulation of these AR-mediated target genes is not fully understood. We have previously demonstrated a unique role of HOXB13 homeodomain protein as an AR repressor. Expression of HOXB13 was highly restricted to the prostate and its suppression dramatically increased hormone-activated AR transactivation, suggesting that prostate-specific HOXB13 was a highly potent transcriptional regulator. In this report, we demonstrated the action mechanism of HOXB13 as an AR repressor. HOXB13 suppressed androgen-stimulated AR activity by interacting with AR. HOXB13 did neither bind to AR responsive elements nor disturb nuclear translocation of AR in response to androgen. In PCa specimen, we also observed mutual expression pattern of HOXB13 and AR. These results suggest that HOXB13 not only serve as a DNA-bound transcription factor but play an important role as an AR-interacting repressor to modulate hormone-activated androgen receptor signals. Further extensive studies will uncover a novel mechanism for regulating AR-signaling pathway to lead to expose new role of HOXB13 as a non-DNA-binding transcriptional repressor.

Three-dimensional ultrasonographic application for analyzing synovial hypertrophy of the knee in patients with osteoarthritis.

OBJECTIVE: The purpose of this study was to evaluate 3-dimensional (3D) ultrasonography for the visualization of intra-articular synovial hypertrophy in patients with osteoarthritis. METHODS: Knee joints of 22 patients with osteoarthritis were examined by 3D ultrasonography, and their synovial fluids were analyzed. Ultrasonographic image patterns, vascular endothelial growth factor and transforming growth factor beta concentrations in synovial fluid, and serum inflammatory markers were analyzed. RESULTS: It was possible to visualize the intra-articular structure by 3D ultrasonography. Three-dimensional ultrasonography revealed various interesting stereoscopic views of the synovial structures, and the patterns of synovial proliferation ranged from simple proliferations to complex shrubby structures. Patients with a more complex and proliferative pattern in the synovium tended to have higher C-reactive protein concentrations, but this difference was not significant (P = .09). The concentrations of vascular endothelial growth factor and transforming growth factor beta in synovial fluid were significantly higher in patients with complex hypertrophy (P < .05). CONCLUSIONS: Three-dimensional technology was useful in delineating the shape of the synovium. It may have a possible impact on future imaging in rheumatology.

Visualization and localization of rheumatoid knee synovitis with FDG-PET/CT images.

We annually evaluated (18)F-fluorodeoxyglucose-positron emission tomography/ computed tomography (FDG-PET/CT) scans for three consecutive years in a patient with rheumatoid arthritis. The inflammatory activity of the rheumatoid synovium was visualized in coronal and transverse sections by FDG-PET/CT. The extent and area of the synovial inflammation was relatively well delineated, and this technique was more informative in detecting inflammation than were conventional X-rays.

Application of three-dimensional computed tomography for the rheumatoid wrist.

Recent technical advances in computed tomography (CT) and the introduction of three-dimensional (3D) image reconstruction through computer systems make distinct visualization of tiny defects in the hand and wrist a feasible task. Three wrists from three patients -- two of whom are patients with rheumatoid arthritis and one with osteoarthritis -- were evaluated by 3D CT. Images were obtained with a multidetector-row CT scanner. Bony wrist structures including erosions were observed in the patients with arthritis by means of 3D CT. 3D CT could clearly visualize bone-erosive lesions. It also revealed various interesting stereoscopic views of bony structures unattainable with conventional radiographic studies. 3D CT may serve to be interesting in future imaging studies in the rheumatology field.