Characteristics of monosodium urate crystal deposition in the foot in the different stages of gout by dual-energy computed tomography.

OBJECTIVE: To compare the characteristics of monosodium urate (MSU) crystal deposition at specific anatomical sites of the foot detected by dual-energy computed tomography in patients with different stages of gout. MATERIALS AND METHODS: This study included 101 patients with gout, 64 had early gout (<3 years) and 37 had late gout (>3 years). We retrospectively compared the total volumes of MSU crystals, the detection rates, and the morphology of MSU crystals at specific anatomical sites in the foot of the patients with different gout durations. RESULTS: The total volume of MSU crystals in patients with early gout was significantly smaller than that in patients with late gout (P < 0.05). The detection rates and morphology of MSU crystals in the anterior calf tendons, ankle joints, tarsometatarsal joints, and metatarsophalangeal joints differed significantly between the patients with early and late gout (P < 0.05). There were no significant differences in the detection rates of submillimeter MSU crystals at the other specific anatomical sites, except for the tendons of the anterior calf, the ankle joint, and the metatarsal joint (P > 0.05). The submillimeter MSU crystal deposition was most common in the tendons of the posterior calf, the proportions in patients with early gout and late gout were 85.9% and 70.3%. Only submillimeter deposition existed in 52 patients (81.3%) with early gout and 11 patients (29.7%) with late gout at all sites of the foot. CONCLUSION: Dual-energy computed tomography detection of submillimeter MSU crystal deposits in the foot is of great significance for the diagnosis of gout, especially along tendons.

Study on the compatibility effect and active constituents of Atractylodis Rhizoma in Ermiao Wan against Acute Gouty Arthritis.

ETHNOPHARMACOLOGICAL RELEVANCE: Ermiao Wan (EMW), composed of Atractylodis Rhizoma (AR) and Phellodendri Chinensis Cortex (PC), is a classical traditional Chinese medicine prescription having been used to treat the disease named "Tong Feng", which is described as "ache in bones and joints" with the same symptom of modern disease named acute gouty arthritis for many years in TCM clinical practice. Besides, both PC and AR were considered to be effective in anti-inflammatory according to modern pharmacological research. AIM OF THE STUDY: Present study was undertaken to probe the compatibility rationality between the two herbs PC and AR in EMW and the active constituents of AR against acute gouty arthritis (AGA). MATERIALS AND METHODS: Rat model of AGA was induced by intra-articular injection of monosodium urate (MSU) crystal suspension, and PC combined with or without different AR extracts were used for AGA treatment. Ankle joint swelling, proinflammatory cytokines in serum and pathological changes of synovium were investigated. Using the developed UHPLC-QQQ-MS method, the plasma concentrations of the primary alkaloids in PC, such as berberine, phellodendrine, magnoflorine, jatrorrhizine, berberrubine, palmatine, and tetrahydropalmatine, in AGA rat were determined, and pharmacokinetics properties were compared following oral administration of PC, PC combined with or without different AR extracts. RESULTS: PC, PC combined with AR volatile oil (VO) extract or PC combined with whole AR extract significantly attenuated the ankle joint swelling of AGA rats. Besides, the combination of PC and VO extract of AR showed superior efficacy than other groups in ameliorating ankle joint swelling, reducing the IL-6 expression in serum and improving tissue lesions of ankle joints. Furthermore, it turned out that the VO extract of AR increased the blood exposure level of PC related alkaloids than non-volatile oil (NVO) extract of AR, by comparing the pharmacokinetic results of each group. CONCLUSIONS: The VO components of AR were the key compatible materials to combine with PC in EMW for AGA treatment. Moreover, the enhanced anti-AGA activity of PC after combining with VO extract of AR may attribute to the influence of VO on the pharmacokinetics of PC. This study may provide useful information for elucidating the compatibility effects of AR in EMW against AGA.

Effect of canakinumab on clinical and biochemical parameters in acute gouty arthritis: a meta-analysis.

BACKGROUND: Targeted anti-IL-1ß therapy may be a valuable option for the management of gouty arthritis. The present meta-analysis has evaluated the effect of canakinumab, an anti-IL-1ß monoclonal antibody in gouty arthritis. METHODS: A standard meta-analysis protocol was developed and after performing a comprehensive literature search in MEDLINE, Cochrane, and International Clinical Trial Registry Platform (ICTRP), reviewers assessed eligibility and extracted data from three relevant articles. A random-effects model was used to estimate the pooled effect size as the mean difference in Visual Analouge Scale (VAS) score, serum hsCRP, serum Amyloid A, and risk ratio for global assessment between the groups. Quality assessment was done using the risk of bias assessment tool and summary of findings was prepared using standard Cochrane methodology with GradePro GDT. RESULTS: Treatment with canakinumab showed a mean reduction of VAS score by 14.59 mm [95% CI - 19.42 to - 9.77], serum hsCRP by 15.36 mg/L [95% CI 1.62-29.11], serum Amyloid A by 67.18 mg/L [95% CI 17.06-117.31], and improvement in patient global assessment (RR = 1.478; 95% CI 1.29-1.67) and physician global assessment (RR = 1.44; 95% CI 1.28-1.61). The probability that future studies may have a mean difference in VAS score less than zero has been calculated to be 27.3% using a cumulative distribution function (CDF) calculator. CONCLUSION: This meta-analysis shows the beneficial effect of canakinumab over triamcinolone by reducing VAS score, serum hsCRP, serum amyloid A, and improvement in global assessments in acute gouty arthritis.

Characteristics of voltage-gated potassium currents in monosodium urate induced gouty arthritis in mice.

OBJECTIVE: To evaluate the role of K+ channels in pain following gouty arthritis. METHODS: The model of acute gouty arthritis was induced by monosodium urate (MSU) in mice. The swelling degree was determined by measuring the circumference of the ankle joint. Mechanical hyperalgesia was detected by von Frey filaments. Two types of K+ currents, A-type currents (IA) and delayed rectifier currents (IK), were recorded in dorsal root ganglion (DRG) neurons using patch-clamp techniques. RESULTS: The swelling degree reached its maximum at 10 h and the minimum pain threshold was maintained between 8 and 48 h after MSU treatment in mice. The amplitudes of IA and IK in DRG neurons were moderately increased on day 1 after MSU treatment, and then, they were gradually decreased with times and reached their minimums on day 4 (for IA) or 5 (for IK). Compared with control group, the activation curve of IA was significantly shifted to more positive potential and the recovery time of IA from inactivation was markedly prolonged, but inactivation and frequency dependence of IA appeared unaffected in MSU-treated group. Additionally, no change was observed in the activation curve of IK after MSU treatment. The excitability was significantly higher in the MSU group than in the control group. CONCLUSIONS: MSU-induced gout pain may be related to the hyperexcitability of DRG neurons elicited by decreasing K+ currents.

MiR-146a alleviates inflammation of acute gouty arthritis rats through TLR4/MyD88 signal transduction pathway.

OBJECTIVE: The aim of this study was to explore the effect of micro-ribonucleic acid (miR)-146a on acute gouty arthritis rats through Toll-like receptor-4/myeloid differentiation factor 88 (TLR4/MyD88) signal transduction pathway. MATERIALS AND METHODS: A total of 30 clean-grade Sprague-Dawley rats were divided into three groups, including agomiR-146a group (n=10), antagomiR-146a group (n=10) and negative control group (NC, n=10). The model was successfully established via a one-time injection of sodium urate into ankle joint cavity. Subsequently, agomiR-146a (10 µL), antagomiR-146a (10 µL) and normal saline (10 µL) were intrathecally injected into rats in the three groups at 1 h before injection and 12 h, 24 h, 48 h and 72 h after injection, respectively. The ankle joint swelling index, joint dysfunction index and joint inflammation index of rats in the three groups were closely monitored. After 72 h of observation, the rats were euthanized, and synovial tissues were collected from the knee joint. The expression and distribution of nuclear factor-κB (NF-κB) in synovial tissues were detected using the immunohistochemical method. Meanwhile, the expression levels of inflammatory factors, including tumor necrosis factor-α (TNF-α), interleukin-1 (IL-1) and interleukin-6 (IL-6) were detected via enzyme-linked immunosorbent assay. Furthermore, the mRNA and protein expression levels of TLR4 and MyD88 were detected via quantitative Real Time-Polymerase Chain Reaction (qRT-PCR) and Western blotting, respectively. RESULTS: No statistically significant differences in the joint swelling index, joint dysfunction index, joint inflammation index, TLR4 and MyD88 and related inflammatory factors were found between the NC group and antagomiR-146a group. Compared with the NC group, agomiR-146a group showed markedly reduced ankle joint swelling index (p<0.05). Meanwhile, joint landing behavior and inflammatory swelling were significantly relieved in the agomiR-146a group (p<0.05). The mRNA and protein expression levels of TLR4 and MyD88 were remarkably decreased as well (p<0.05). Furthermore, the expression and distribution of NF-κB in synovial tissues of agomiR-146a group was markedly reduced when compared with the NC group (p<0.05). In addition, agomiR-146a group exhibited significantly lower expression levels of inflammatory factors (TNF-α, IL-1 and IL-6) in synovial tissues (p<0.05). CONCLUSIONS: MiR-146a alleviates joint inflammation of acute arthritis in rats through the TLR4/MyD88/NF-κB signaling pathway, which may become a new therapeutic target.

Better understanding of acute gouty attack using CT perfusion in a rabbit model.

OBJECTIVE: To assess hemodynamic changes related to acute gouty knee arthritis in a rabbit with CT perfusion (CTP) METHODS: Forty-two rabbits were randomly separated into two groups: the treated group of 30 and the control group of 12. The right knee was injected with monosodium urate solution and polymyxin in the treated group and saline and polymyxin in the control group. At 2, 16, 32, 48, 60, and 72 h after injection, five rabbits from the treated group and two rabbits from the control group were selected for CTP. At each time point, blood flow (BF), blood volume (BV), and clearance rate (CL) were measured, and microvessel density (MVD) was evaluated with a microscope. RESULTS: In the treated group, BF, BV, CL, and MVD were significantly higher than in the control group (p < 0.001). Differences within paired comparison of BV, BF, CL, and MVD were all significant (all p < 0.001). Peak time of BV, BF, and MVD was 32 h and 48 h for CL. After multivariate stepwise linear regression analysis, BV was linearly associated with MVD and vice versa, which also applied to BF with MVD and BF with CL, separately. The ascending rate of MVD was the highest among that of all parameters; so was the descending rate of CL. CONCLUSION: CTP in this rabbit knee model accurately detected hemodynamic changes during a gouty attack. KEY POINTS: • Acute gouty arthritis can be evaluated with CTP in a rabbit knee model. • Following injection of MSU crystals, producing an acute gouty attack, CTP successfully assessed hemodynamic changes. • The ascending rate of MVD was the highest among that of all parameters; so was the descending rate of CL.

Renal excretion is a cause of decreased serum uric acid during acute gout.

AIMS: To evaluate the fluctuation of serum uric acid (SUA) during acute gout (AG) and explore its potential mechanisms. METHODS: Data such as SUA, urinary uric acid and 24-hour uric acid urinary excretion were collected from 126 patients diagnosed with gout and were analyzed. RESULTS: Serum uric acid was negatively correlated with age in gout patients, and significantly elevated in patients aged ≤50 years. Twenty-four-hour uric acid urinary excretion was affected by SUA, creatinine clearance, age, body mass index and urine volume. In contrast, clearance of uric acid and fractional excretion of uric acid (FEur) were more stable. SUA was significantly downregulated during acute attacks. Of the AG patients, 34.92% had detected SUA <420 µmol/L. Clearance of uric acid and FEur were notably increased in patients during acute attacks, especially in patients with SUA <420 µmol/L. CONCLUSION: This study demonstrated that the level of SUA was remarkably upregulated in young gout patients. Therefore, early onset of gout should be considered of great importance. SUA was downregulated during acute gouty arthritis, which might be associated with increased urinary excretion of uric acid.

Dysadipokinemia in patients with gout and its association with the disease activity.

OBJECTIVE: Introduction: In recent years, the role of adipokines in the development of rheumatic diseases has been a pressing issue. The available data suggest the dysadipokinemia in patients with rheumatoid arthritis, osteoarthritis and psoriatic arthritis. However, there is no data on changes in the levels of adipokines in patients with gout and their association with the activity of inflammatory process. The aim was to study the levels of adipokines in gout patients and evaluate their association with the disease activity. PATIENTS AND METHODS: Materials and methods: We examined 151 male patients with gout. The control group consisted of 31 practically healthy men, represented by age. We used the Gout Activity Score (GAS) to assess gout severity. The levels of leptin and adiponectin were determined using the ELISA kit. For comprehensive evaluation of dysadipokinemia, we used a logarithmic ratio of leptin to adiponectin (lg A/L). Primary processing of results was carried out using MS Excel and Statistica SPSS22 statistical software packages. RESULTS: Results: The patients with gout demonstrated higher leptin levels, lower levels of adiponectin, and lower lg A/L compared to practically healthy individuals. Among patients with gout, the disturbance of adipokin status was most pronounced in patients with tophi. Patients with high GAS activity had maximum disturbance of adipokin profile by lg A/L, while the manifestations of dysadipokinemia were minimal in the group with low activity of the disease. It was established that GAS disease activity, BMI, and the number of joints under attack may be considered the most significant independent predictors of dysadipokinemia. CONCLUSION: Conclusions: The patients with gout presented an increase in leptin level, a decrease in adiponectin level, and a decrease in the ratio lg A/L. Dysadipokinemia was associated with high disease activity and could serve as a prognostic factor for assessing the severity of the disease.

Effects of pharmacological reversal of hyperuricemia on features of the metabolic syndrome in patients with gouty arthritis.

Hyperuricemia has been associated in epidemiological studies with the development of obesity, hypertension, insulin resistance and type 2 diabetes. Nevertheless, it remains unclear whether lowering of serum uric acid (UA) alters any of the features of the metabolic syndrome. In this prospective study (ClinicalTrials.gov identifier: NCT01654276), 24 patients with gouty arthritis and hyperuricemia were treated for 6 months with the xanthine oxidase inhibitor febuxostat to lower serum UA to <6 mg/dL. Measurements of 24 hours ambulatory blood pressure (ABP) and serum and urine markers of the metabolic syndrome were measured at baseline and at the end of 6 months of febuxostat. The study population consisted of 18 men and 6 women, 18 of which completed the baseline and 6 months visits. Serum UA decreased significantly from 8.7±1.5 mg/dL at baseline to 4.4±1.1 mg/dL at 6 months (P<0.0001). During that time frame, there was no significant change in body mass index, systolic or diastolic blood pressure measured by 24 hours ABP monitor, serum glucose, insulin or homeostatic model assessment for insulin resistance, serum total and high-density lipoprotein-cholesterol, serum triglycerides or urine pH (P>0.05 for all). There was no correlation between parameters of the metabolic syndrome and the decline in serum UA or serum UA achieved at study end. In conclusion, in patients with gouty arthritis, UA lowering with febuxostat below 6 mg/dL had no significant impact on features of the metabolic syndrome.

Effects of Mollugo pentaphylla extract on monosodium urate crystal-induced gouty arthritis in mice.

BACKGROUND: Gout is an inflammatory condition induced by the deposition of monosodium urate (MSU) crystals in joints and soft tissues, and it can lead to acute or chronic arthritis. MSU are pro-inflammatory stimuli that can initiate, amplify and sustain an intense inflammatory response. In this study, we evaluated the anti-inflammatory effect of an extract of Mollugo pentaphylla (MPE) on MSU-induced gouty arthritis in a mouse model. METHOD: An MSU crystal suspension (4 mg/50 µL) was injected intradermally into the right paw. The mice were orally administered MPE (150 mg/kg or 300 mg/kg) or the positive control drug colchicine (1 mg/kg) 1 h before the MSU crystals were injected and then once daily for 3 days. The effects of MPE included inflammatory paw edema and pain upon weight-bearing activity, and we evaluated the inflammatory cytokine expression and paw tissue inflammation-related gene expression. RESULTS: MPE suppressed inflammatory paw edema and pain in the MSU-induced mice. MPE showed anti-inflammatory activity by inhibiting the production of TNF-α, interleukin (IL)-1ß, NLRP3 inflammasome and NF-κB. CONCLUSION: These results suggest that MPE has potent anti-inflammatory activities and may be useful as a therapeutic agent against gouty arthritis.

[Clinical observation of arthroscopic debridement for acute gouty arthritis of the ankle].

OBJECTIVE: To evaluate the effects of arthroscopic debridement for acute gouty arthritis of the ankle. METHODS: Forty-one patients with acute gouty arthritis of the ankle were treated under arthroscopy from January 2010 to June 2012. All the patients were male, age in ranging from 28 to 69 years with an average of 43 years. Eighteen patients were in the left ankles and 23 in the right ankles; 12 cases were firstly attack and 29 cases were recurrent attack. Course of disease was from 2 weeks to 30 months. The American Orthopedic Foot and Ankle Society (AOFAS) Ankle-Hindfoot Scale score was used to evaluate the clinical effects. Number of acute attacks of gouty arthritis were observed. RESULTS: All the patients were followed up at least 12 months. The mean AOFAS Ankle-Hindfoot Scale score increased from 58.44 +/- 9.45 preoperatively to 86.15 +/- 7.36, 83.41 +/- 9.22, 84.10 +/- 8.22 postoperatively at 6, 12, months and the last follow-up respectively. Swelling of the ankle were improved significantly, pain was relieved and the mean number of acute attacks of gouty arthritis decreased significantly. CONCLUSION: Arthroscopy is helpful for the diagnosis of acute gouty arthritis of the ankle and improvement of clinical symptoms and ankle function.

[Histopathophysiology of Gout]. / Histo-Pathophysiologie der Gichtarthritis.

Despite being a frequent cause of arthritis and bone erosions, the underlying cellular and subcellular reaction in gout is insufficiently understood. The inflammasome as intracellular sensor for crystals plays an important role, notably resulting in interleukin (IL)-1 production. Morphologically, hyperplasia of the synovial membrane with joint effusion, along with fibrinogen deposition and influx of neutrophils and lymphocytes are observed. Extracellular NET formation by neutrophils is involved in the regulation of inflammatory tissue reaction. Furthermore, the release of IL-10 and tumor necrosis factor (TNF)-receptors along with lymphocyte proliferation induce the natural resolution of acute gouty arthritis which typically occurs after several days. In contrast to acute gout, tophi consisting of urate crystals are surrounded by histiocytes and multinucleated cells, resembling a foreign body reaction. The deposition of extracellular matrix by fibrocytes is usually observed around tophi. This fibrotic reaction is likely enhanced by Th2-lymphocytes. Bone erosions in gout occur around tophi and are triggered by osteoclast activation through RANK-ligand expression by lymphocytes. In conclusion, understanding the orchestration of inflammation in gout might help to identify new therapeutic targets.

The effect of resveratrol on the recurrent attacks of gouty arthritis.

Gouty arthritis is characterized by inflammation induced by monosodium urate (MSU) crystal deposition, which is resulted by an increase of serum urate concentration. The management of gout, especially the recurrent acute attacks of chronic gouty arthritis, is still a problem to be resolved. In this study, we aimed to develop the preventive and therapeutic effect of resveratrol on gouty arthritis. MSU was used to induce gouty arthritis in the foot pad of C57BL/6 mice. Yeast polysaccharide and potassium oxonate were used to induce hyperuricemia in Kunming mice. Resveratrol was intraperitoneal injected to the mice in the treatment group. The pad inflammation and the level of serum uric acid were investigated to estimate the effect of resveratrol in gouty arthritis. Hyperuricemia was significantly detected in the mice treated with yeast polysaccharide and potassium oxonate, and gouty arthritis was successfully induced with MSU in mice. We further identified that resveratrol inhibited pad swelling and pad 99mTc uptake in gouty mice. Moreover, serum uric acid level was also decreased by resveratrol in hyperuricemia mice. This study highlighted that resveratrol might be applied to prevent the recurrent acute attack of gouty arthritis because of its inhibition of articular inflammation and down-regulation of serum uric acid.

Salivary uric acid as a noninvasive biomarker for monitoring the efficacy of urate-lowering therapy in a patient with chronic gouty arthropathy.

BACKGROUND: Monitoring blood uric acid (UA) is important in all patients on urate-lowering therapy so that the selection of the effective drugs and dosage adjustments could be made until the target level is reached. The issue is that frequent needle jabs are unacceptable. Reported mean levels of salivary UA were 185-240 µmol/l in healthy adults. A linear correlation was demonstrated between UA concentrations in saliva and plasma. We monitored salivary UA instead of plasmatic UA in a patient with gout. METHODS: Allopurinol and benzbromarone were used as the therapeutic drugs. Salivary UA; urinary UA and creatinine; and plasmatic UA, creatinine, kynurenine and tryptophan were measured by HPLC. RESULTS: Salivary UA indicated the efficacy of therapy accurately and conveniently. After eight weeks therapy, the weekly mean levels of salivary UA were reduced and maintained to <300 µmol/l, which was equivalent to <360 µmol/l of plasmatic UA according to the salivary UA/plasmatic UA ratio of this patient. CONCLUSION: Measurement of salivary UA is a noninvasive and useful way for monitoring the status of hyperuricemia and the therapeutic efficacy of urate-lowering therapy. It has value for the management of hyperuricemia and gout.

[Time course of changes in the clinical manifestations of gout in men: data of a 7-year retrospective follow-up].

AIM: To estimate the time course of changes in the clinical manifestations of gout and their risk factors during a long-term follow-up. SUBJECTS AND METHODS: A total of 160 male patients with gout were examined and followed up for a mean of 6.9 ± 2.0 years. Their clinical assessment included determination of the type of arthritis over time, the frequency of arthritis attacks during one year prior to the examination, the presence and number of subcutaneous tophi, inflamed joints, comorbid or co-occurring diseases (CD), allopurinol adherence, dietary compliance, frequency of taking non-steroidal anti-inflammatory drugs (NSAIDs), diuretics, and alcohol. The serum levels of uric acid (UA), glucose, total cholesterol, and glomerular filtration rate were estimated. RESULTS: The number of patients taking allopurinol increased from 19% to 64% (p < 0.0001), its average daily dose was 167.6 ± 94.6 mg. The serum level of UA decreased; 16% of the patients achieved its target level. The number of patients with chronic arthritis was not significantly changed. Their serum level of UA was unchanged; the detection rate of subcutaneous tophi and CD rose. During one year, arthritis attacks were absent in 13% of the patients; 90% of them took allopurinol. In these patients, serum UA levels and body mass index significantly declined and the rate of CD was unchanged. None of 18 patients who had their diet and no allopurinol achieved the target level of UA. CONCLUSION: Among the gouty patients, 36% refrain from the use of allopurinol, only 23% out of them require that its dose be adjusted to achieve the target level of UA. Dietary compliance is insufficient to reach the target level of UA. Chronic arthritis is associated with the increased incidence of CD.

[The specific features of gout in the elderly].

AIM: To determine the specific feature of gout at its onset in the elderly. SUBJECTS AND METHODS: The investigation included 100 patients (74 men and 26 women) with primary gout on the basis of the criteria proposed by S. Wallace et al. (1977). The patients were divided into 2 groups: 1) 51 patients aged over 60 years; 2) 49 patients aged less than 60 years. In Groups 1 and 2, the mean age at gout onset was 66.1 +/- 4.8 and 41.6 +/- 10.0 years, respectively. A comparative retrospective analysis was made to analyze the detection rate for the site of onset gout, the pattern of arthritis, the number of tophus forms, the use of diuretics, small-dose acetylsalicylic acid (ASA), comorbidities, such as hypertension, type 2 diabetes mellitus (T2DM), obesity, chronic renal failure, coronary heart disease, chronic heart failure, and prior myocardial infarction. RESULTS: The disease duration in both groups averaged 8 years. In Groups 1 and 2, first metatarsophalangeal joint arthritis was diagnosed at its onset in 77 and 61%, respectively. In these groups, chronic arthritis was also diagnosed in 19 (37%) and 19 (39%). Examinations revealed tophi in 21 and 37% of cases in Groups 1 and 2, respectively. The administration of diuretics was recorded in 25 (49%) and 17 (35%) patients in these groups. Group 1 patients took low-dose ASA more frequently than Group 2 ones (19 (37%) and 7 (14%) patients, respectively; p = 0.013). Hypertension was identified in 23 (45%) examinees in Group 1 and 17 (40%) ones in Group 2. Both groups were matched for the number of patients with obesity (41 and 43%) and for that of patients with T2DM (15 and 10%, respectively). There were significant differences between the compared groups in the incidence of coronary heart disease, myocardial infarction, and chronic heart disease. CONCLUSION: The patients' age of gout onset does not affect substantial differences in the clinical features of gout with its comparable duration in the young and elderly patients. The main clinical features of gout are unique to both young and elderly patients. Cardiovascular diseases are more common at gout onset in the elderly.

Pain and microcrystalline arthritis.

Microcrystals are responsible for some of the most common and complex arthropathies which are often accompanied by intense, severe pain and inflammatory reactions. The main pathogens are crystals of monosodium urate (MSU), responsible for the gout, calcium pyrophosphate (CPP), which deposits also in various clinical forms of arthopathies, and basic calcium phosphate associated with osteoarthritis. In this context, the microcrystal arthritis is characterized by multiple, acute attacks followed by chronic pain, disability, impaired quality of life, and increased mortality. Given their chronic nature, they represent an ever more urgent public health problem. MSU and CPP crystals are also able to activate nociceptors. The pain in mycrocrystalline arthritis (MCA) is an expression of the inflammatory process. In the course of these diseases there is an abundant release of inflammatory molecules, including prostaglandins 2 and kinins. Interleukin-1 represents the most important cytokine released during the crystal-induced inflammatory process. Therefore, clinically, pain is the most important component of MCA, which lead to functional impairment and disability in a large proportion of the population. It is fundamental to diagnose these diseases as early as possible, and to this aim, to identify appropriate and specific targets for a timely therapeutic intervention.

The effect of bariatric surgery on gout: a comparative study.

BACKGROUND: Obesity is a risk factor for the development of gout. An increased incidence of early gouty attacks after bariatric surgery has been reported, but the data is sparse. The effect of weight loss surgery on the behavior of gout beyond the immediate postoperative phase remains unclear. The objective of this study was to evaluate the pre- and postoperative frequency and features of gouty attacks in bariatric surgery patients. METHODS: Charts were reviewed to identify patients who had gout before bariatric surgery. Demographic and gout-related parameters were recorded. The comparison group consisted of obese individuals with gout who underwent nonbariatric upper abdominal procedures. RESULTS: Ninety-nine morbidly obese patients who underwent bariatric surgery had gout. The comparison group consisted of 56 patients. The incidence of early gouty attack in the first month after surgery was significantly higher in the bariatric group than the nonbariatric group (17.5% versus 1.8%, P = .003). In the bariatric group, 23.8% of patients had at least one gouty attack during the 12-month period before surgery, which dropped to 8.0% during postoperative months 1-13 (P = .005). There was no significant difference in the number of gouty attacks in the comparison group before and after surgery (18.2% versus 11.1%, P = .33). There was a significant reduction in uric acid levels 13-months after bariatric surgery compared with baseline values (9.1±2.0 versus 5.6±2.5 mg/dL, P = .007). CONCLUSION: The frequency of early postoperative gout attacks after bariatric surgery is significantly higher than that of patients undergoing other procedures. However, the incidence decreases significantly after the first postoperative month up to 1 year.