Prevalence of Hypertension in Sudanese Patients With Gouty Arthritis

Background In this study, we aimed to study the frequency of hypertension in Sudanese patients with gouty arthritis attending the largest three tertiary hospitals in Khartoum and correlate it with serum uric acid levels. Methodology An observational, descriptive, cross-sectional, hospital-based study was conducted in rheumatology clinics in Khartoum state, Sudan, from August 2020 to January 2021 involving 100 participants. Data were collected, prepared, and analyzed using SPSS version 25.0 (IBM Corp., Armonk, NY, USA). Results In this study, 100 participants were enrolled. The majority were males (79%), with 45% of the participants in the age group of 61-75 years. Overall, 89% of participants had symptoms of gouty arthritis, with the knee being the most common joint affected in 27% of participants. Most participants had a uric acid level above the target (6 mg/dL). The most frequently used uric acid lowering agent was found to be allopurinol in 85% of the patients. Furthermore, among those with gouty arthritis, 51% had hypertension with nearly half being insufficiently controlled. The frequency of undiagnosed hypertension among the participants was found to be 19%, which was statistically significant among gouty arthritis patients (p-value < 0.0001). Upon further analysis of our hypertensive participants, 79.5% of males (n = 35) had high blood pressure levels, which was statistically significant as well (p-value = 0.005), with the highest prevalence being among the age group of 61-75 years. Of those who were hypertensive, 51% had a history of concomitant comorbidity. Overall, 90% of the hypertensive participants (n = 40) had joint symptoms. Moreover, serum uric acid level was above the target in 93% of the participants. Conclusions Hypertension was found to be the most frequently recognized comorbidity in gouty arthritic patients, with more than a third remaining undiagnosed. Moreover, the male gender was a significant risk factor for hypertension among the gouty arthritis participants. Nevertheless, most patients with high blood pressure levels had concurrent elevated uric acid levels.

Incidence of allopurinol-induced severe cutaneous adverse drug reaction in Malaysia

AIMS

Allopurinol is known to cause severe cutaneous adverse drug reactions (SCAR) in Malaysia. However, the incidence of allopurinol-induced SCAR is unknown. Therefore, we aimed to determine the incidence of allopurinol-induced SCAR in Malaysia over 5 years from 2015 to 2019.

METHODS

This retrospective analysis was done in collaboration with the National Pharmaceutical Regulatory Agency (NPRA). All allopurinol-induced adverse drug reaction cases reported to NPRA from 2015 to 2019 were extracted. Allopurinol-induced SCAR cases were identified and the incidence over the 5 years was calculated.

RESULTS

Incidence of allopurinol-induced SCAR averaged at 2.5 cases per 1000 new users over the 5-year period, with a reducing trend from 3.2 per 1000 new users in 2015 to 2.25 per 1000 in 2019; despite the increasing number of adverse drug reaction cases being reported over the years. Stevens-Johnson syndrome was the commonest form of allopurinol-induced SCAR reported, at 143 cases (46.8% of total SCAR reported). Among Malaysia's 3 main ethnicities, the Chinese had the highest percentages of allopurinol-induced SCAR when compared to the Bumiputera and Indians (3.18 × 10^-4 %).

CONCLUSION

The estimated incidence of allopurinol-induced SCAR in Malaysia from 2015 to 2019 was 2.5 cases per 1000 new users. This figure is consistent with the incidence reported in other Asian countries, namely Taiwan and Thailand.

A meta-analysis of allopurinol therapy and the risk of prostate cancer

Objective:

The aim of the study was to investigate the risk of prostate cancer among people with gout and/or hyperuricemia who used allopurinol and who did not use allopurinol.

Methods:

We conducted a meta-analysis to identify the cohort and case-control studies by searching PubMed and Web of Science. We used the random-effects model to calculate the pooled risk ratio with 95% confidence interval for the risk of prostate cancer associated with allopurinol treatment.

Results:

There were 5 cohort studies and 2 case-control studies included in the meta-analysis. All 7 eligible studies were published between 2012 and 2021. The study period ranged from 8 to 13years. The number of study subjects ranged from 25,770 to 1,623,550. The age of study subjects ranged from 20 to 99years. Overall, allopurinol treatment was not associated with the risk of prostate cancer (risk ratio = 1.13, 95% confidence interval = 0.96-1.34 and P = .13). The heterogeneity was high between studies (I2 = 93%).

Conclusions:

Our meta-analysis reveals that no association can be found between allopurinol treatment and the risk of prostate cancer among people with gout and/or hyperuricemia. We propose that the inhibition of xanthine oxidase and the reduction of serum uric acid via allopurinol treatment do not affect the probability of developing prostate cancer. Further studies are needed to confirm our findings.

Key Points

Fixed drug eruption in a patient of HLA-B*58:01 negative after allopurinol administration: A case report

WHAT IS KNOWN AND OBJECTIVE

Allopurinol is widely used for hyperuricemia and gouty arthritis, but is associated with cutaneous adverse drug reactions (CADRs). HLA-B*58:01 is a highly specific and effective genetic marker for the detection of allopurinol-induced CADRs, especially for Asian descents.

CASE SUMMARY

A 60-year-old Chinese Han male patient took allopurinol for lowering uric acid after the negative result from HLA-B*58:01 testing. Then, he experienced episodes of well-demarcated pruritic erythematous patches on the whole body that developed into blisters and pustular eruption. Fixed drug eruption (FDE) was diagnosed by skin biopsy and improved with withdrawal and hormone treatments.

WHAT IS NEW AND CONCLUSION

It should be kept in mind that cutaneous drug eruption might occur after allopurinol administration in Asians of HLA-B*58:01 negative. Awareness among medical practitioners about FDE can lead to correct diagnosis, treatment and decreased damage as well as lower therapeutic costs.

Sample preparation and quantification of polar drug, allopurinol, in human plasma using LCMSMS

A fast, selective and reproducible LC-MS/MS method with simple sample preparation was developed and validated for a polar compound, allopurinol in human plasma, using acyclovir as internal standard (IS). Chromatographic separation was achieved using Agilent Poroshell 120 EC-C₁₈ (100 × 2.1 mmID, 2.7 µm) analytical column. The mobile phase was comprised of 0.1%v/v formic acid-methanol (95:05; v/v), at a flow rate of 0.45 mL/min. The effect of different protein precipitation agents used in sample preparation such as methanol, acetonitrile, a mixture of acetonitrile-methanol and a mixture of acetonitrile-acetone were evaluated to optimize the extraction efficiency of allopurinol and IS. The use of acetone-acetonitrile (50:50, v/v) as protein precipitating agent shortened the sample preparation time and improved the recovery of allopurinol to above 93%. The IS-normalised matrix factors at two concentration levels were 1.0, with CV of 5.1% and 4.2%. Allopurinol in plasma was stable at benchtop for 24 h, in autosampler tray for 48 h, in instrumentation room for 48 h, in freezer after 7 freeze-thaw cycles and in freezer for 140 days. Allopurinol stock standard solutions were stable for 140 days at room temperature and in the chiller. The short sample run time of the validated bioanalytical method allowed high throughput analysis of plasma samples in pharmacokinetic study of an allopurinol formulation. The robustness and reproducibility of the bioanalytical method was reaffirmed through incurred sample reanalysis (ISR).

What's new on the front-line of gout pharmacotherapy?

INTRODUCTION

Gout is the most common form of inflammatory arthritis affecting millions of people around the world. Painful flares and tophaceous deposits can be debilitating, reducing quality of life among those affected and putting strain on health care systems.

AREAS COVERED

This review provides an overview of the treatment of gout for flare pain management and lowering serum urate. Firstline agents are discussed with emphasis on emerging evidence. Novel therapies are also covered.

EXPERT OPINION

Lifestyle modifications form a part of gout prevention. Regarding gout flare pharmacotherapy NSAIDs, colchicine and glucocorticoids are first line agents. The IL-1β antagonists also are highly effective for arresting flares but their cost-effectiveness render them as salvage therapies. Allopurinol is an agent of first choice for urate lowering therapy (ULT). In South East Asian and Black populations screening for HLA*B58:01 mutation is a cost-effective approach to decrease the occurrence of the rare but potentially very serious allopurinol hypersensitivity syndrome (AHS.). Febuxostat is another efficacious urate lowering therapy but it has received U.S. FDA black box warning for cardiovascular safety and careful consideration is warranted before its initiation in patients with high cardiovascular risk. Novel uricosurics are a class for continued drug development; verinurad and arhalofenate are agents with future promise. For patients with recalcitrant gout, pegloticase is another effective option in the rheumatologist's armamentarium. Its immunogenicity significantly threatens the achievement of sustained urate lowering responses. Abrogating pegloticase's immunogenicity with immunomodulatory co-therapy may lend to sustained efficacy.

Genotyping for HLA Risk Alleles to Prevent Drug Hypersensitivity Reactions: Impact Analysis

Human Leukocyte Antigen (HLA) variants can be a risk factor for developing potentially fatal drug hypersensitivity reactions. Our aim was to estimate the potential impact of genotyping for the HLA risk alleles incorporated in the Dutch Pharmacogenetics Working Group (DPWG) guidelines in The Netherlands. We estimated the number of hypersensitivity reactions and associated deaths that can be avoided annually by genotyping for these HLA risk alleles. Additionally, the cost-effectiveness was estimated. Nationwide implementation of genotyping HLA risk alleles before initiating drugs with an actionable drug-gene interaction can potentially save the life of seven allopurinol initiators and two flucloxacillin initiators each year in The Netherlands. Besides these deaths, 28 cases of abacavir hypersensitivity, 24 cases of allopurinol induced SCARs, 6 cases of carbamazepine induced DRESS and 22 cases of flucloxacillin induced DILI can be prevented. Genotyping HLA-B*5701 in abacavir initiators has a number needed to genotype of 31 to prevent one case of abacavir hypersensitivity and is cost-saving. Genotyping HLA-B*5801 in allopurinol initiators has a number needed to genotype of 1149 to prevent one case of SCAR but is still cost-effective. Genotyping before initiating antiepileptic drugs or flucloxacillin is not cost-effective. Our results confirm the need for mandatory testing of HLA-B*5701 in abacavir initiators, as indicated in the drug label, and show genotyping of HLA-B*5801 in allopurinol initiators should be considered.

Topical Allopurinol-Loaded Nanostructured Lipid Carriers: A Novel Approach for Wound Healing Management

Nanostructured lipid carriers (NLC) have been widely studied as delivery systems for a variety of routes, including the skin. Their composition results in an imperfect lipid matrix, allowing increased drug encapsulation. Allopurinol (AP), a xanthine oxidase inhibitor, is characterized by low water solubility and high melting point, which has hampered its use through the topical route. In this work, AP was incorporated in a NLC formulation to enhance drug-carrier association and skin delivery as a topical approach to treat wounds. AP-NLC system was characterized in terms of size, charge, rheological behavior, and in vitro skin permeation. The in vitro cytotoxicity was evaluated using HaCaT cells. The wound healing efficacy of the AP-NLC formulation on animal skin lesions was evaluated in male Wistar rats. The AP-NLC presented a mean size of 193 ± 15 nm with a PdI of 0.240 ± 0.02, zeta potential values around −49.6 mV, and an encapsulation efficiency of 52.2%. The AP-NLC formulation presented an adequate profile to be used topically, since epidermal and dermal drug retention were achieved. No reduction in HaCaT cells viability was observed at the tested concentrations (AP < 10 μg/mL). The in vivo application of the AP-NLC formulation resulted in the regeneration of skin lesions when compared with non-treated controls.

A Novel Use of Allopurinol as A Quorum-Sensing Inhibitor in Pseudomonas aeruginosa

Pseudomonas aeruginosa can cause a variety of healthcare-associated infections by its arsenal of virulence factors. Virulence factor production is largely controlled by the cell-to-cell communication system termed quorum sensing (QS). Targeting QS may be a good approach to inhibit the production of virulence factors and attenuate pathogenicity without exerting selective stress on bacterial growth. This will greatly reduce the emergence of resistant mutants. In this work, we investigated the anti-virulence and anti-QS activities of the FDA-approved drug allopurinol against the P. aeruginosa PAO1 strain. Allopurinol at 200 µg/mL (1/10 MIC) significantly decreased the production of the QS-controlled Chromobacterium violaceum CV026 violet pigment violacein and other P. aeruginosa QS-controlled virulence factors phenotypically. Furthermore, allopurinol reduced the infiltration of P. aeruginosa and leucocytes and diminished the congestion in the liver and kidney tissues of infected mice. In silico study showed that allopurinol could compete with the autoinducers on binding to the receptors LasR and RhlR by hydrogen bonding. On the molecular level, qRT-PCR proved that allopurinol showed a significant downregulating effect on all tested QS-encoding genes that regulate virulence factor production. In summary, allopurinol is a promising QS inhibitor that may be useful in the future treatment of P. aeruginosa infection.

Risk of Hematologic Events With Coadministration of Methotrexate and the Breast Cancer Resistance Protein Inhibitor Febuxostat

BACKGROUND

The breast cancer resistance protein (BCRP) is a key drug transporter found in the liver, kidney, central nervous system, and gastrointestinal tract. Due to the wide expression of BCRP, interactions of other drugs with methotrexate (MTX) may differ in oral and intravenous MTX users, and understanding of these interactions may be useful in preventing severe adverse events. Febuxostat, a urate-lowering drug, inhibits BCRP.

OBJECTIVE

The objective of this study was to clarify the differences in the drug-drug interaction profiles of oral and intravenous methotrexate, associated with BCRP.

METHODS

We analyzed the Japanese Adverse Drug Event Report database and compared the frequency of hematologic events in patients taking oral and intravenous MTX, with or without the concomitant use of febuxostat or allopurinol. Hematologic events were defined as pancytopenia and neutropenia. Multiple logistic regression analysis was then used to identify the risk factors for hematologic events in oral and intravenous MTX users.

RESULTS

We identified 8 453 oral and 810 intravenous MTX users with 546 and 126 cases of hematologic events, respectively. Compared with those not using febuxostat, a disproportionate number of hematologic events was observed in intravenous MTX users concomitantly using febuxostat (P < 0.01). The multivariate logistic analysis of intravenous MTX users showed that hematologic events were significantly associated with febuxostat use (P < 0.01) and age ≥ 60 years (P < 0.01).

CONCLUSION AND RELEVANCE

Our findings suggest that patients being treated with intravenous MTX who concomitantly use febuxostat may be at an increased risk of hematologic events, presumably due to BCRP-mediated drug-drug interaction.

Left Ventricular Hypertrophy in Diabetic Cardiomyopathy: A Target for Intervention

Heart failure is an important manifestation of diabetic heart disease. Before the development of symptomatic heart failure, as much as 50% of patients with type 2 diabetes mellitus (T2DM) develop asymptomatic left ventricular dysfunction including left ventricular hypertrophy (LVH). Left ventricular hypertrophy (LVH) is highly prevalent in patients with T2DM and is a strong predictor of adverse cardiovascular outcomes including heart failure. Importantly regression of LVH with antihypertensive treatment especially renin angiotensin system blockers reduces cardiovascular morbidity and mortality. However, this approach is only partially effective since LVH persists in 20% of patients with hypertension who attain target blood pressure, implicating the role of other potential mechanisms in the development of LVH. Moreover, the pathophysiology of LVH in T2DM remains unclear and is not fully explained by the hyperglycemia-associated cellular alterations. There is a growing body of evidence that supports the role of inflammation, oxidative stress, AMP-activated kinase (AMPK) and insulin resistance in mediating the development of LVH. The recognition of asymptomatic LVH may offer an opportune target for intervention with cardio-protective therapy in these at-risk patients. In this article, we provide a review of some of the key clinical studies that evaluated the effects of allopurinol, SGLT2 inhibitor and metformin in regressing LVH in patients with and without T2DM.

A Head-To-Head Comparison of Benzbromarone and Allopurinol on the Risk of Type 2 Diabetes Mellitus in People With Asymptomatic Hyperuricemia

Objective: The study aimed to thoroughly address the influence of benzbromarone and allopurinol on the risk of the development of type 2 diabetes mellitus (T2DM) in people with asymptomatic hyperuricemia. Methods: We conducted a retrospective cohort study to examine the 2000-2015 national dataset containing all claims data of 23 million beneficiaries in Taiwan. Subjects who already had diabetes mellitus, gout-related diseases, and any cancer prior to the index date were excluded. Asymptomatic hyperuricemia was defined as subjects taking urate-lowering drugs who never had a gout flare. Subjects aged 20-84 with asymptomatic hyperuricemia who had benzbromarone prescriptions were selected as the benzbromarone group. Sex-matched and age-matched subjects with asymptomatic hyperuricemia who had allopurinol prescriptions were identified as the allopurinol group. The maximum follow-up duration was set as 5 years in our study. The outcome was set as subjects who had a new diagnosis of T2DM. The incidence density of T2DM was calculated in the benzbromarone and allopurinol groups. The hazard ratio (HR) and 95% confidence interval (CI) for T2DM was utilized to estimate the association between medications and the risk of T2DM. Results: The incidence of T2DM among benzbromarone users was significantly lower than that of allopurinol users (7.91 versus 8.48 per 100 person-years, incidence rate ratio = 0.93, and 95% CI = 0.87-0.99). After adjustment for co-variables, the adjusted HR of T2DM would be 0.91 (95% CI = 0.85-0.98 and p = 0.008) in benzbromarone users as compared to allopurinol users. Conclusion: There is a small but statistically significant risk reduction of developing T2DM in people with asymptomatic hyperuricemia taking benzbromarone as compared to those taking allopurinol during 5 years of follow-up. It indicates a future research direction for the use of individual urate-lowering drugs on the prevention of T2DM in the general population.

Optimizing Thiopurine Therapy with a Xanthine Oxidase Inhibitor in Patients with Systemic Autoimmune Diseases: A Single-Centre Experience

Background

Thiopurines are a mainstay of therapy for autoimmune diseases. However, up to 20% to 30% of patients experience overproduction of the methylated metabolites, known as 6-MMP, to the detriment of the active metabolite, 6-thioguanine nucleotide (6-TGN). These patients, commonly referred to as "shunters", are predisposed to thiopurine resistance and hepatotoxicity. In patients with inflammatory bowel diseases, the combination of thiopurine with a xanthine oxidase inhibitor (XOI) is used to reverse this skewed metabolism and to prevent treatment failure or hepatotoxicity. Data on the use of this strategy for patients with other diseases are limited.

Objectives

To investigate and describe the use of thiopurine-XOI combination therapy in shunters with systemic autoimmune diseases.

Methods

Shunters treated in the study hospital between January 1, 2005, and December 31, 2015, were identified using the hospital's laboratory database, and clinical data were collected retrospectively. For each patient with optimization of thiopurine therapy, clinical and laboratory data were assessed over a 6-month period.

Results

Thirty-four patients were identified as shunters; for 14 of these patients, thiopurine therapy was optimized with an XOI. In these 14 patients, the median dose of azathioprine was reduced from 1.95 to 0.78 mg/kg with combination therapy. In addition, median 6-TGN level increased from 135 to 385 pmol/8 × 10⁸ erythrocytes (p = 0.001); furthermore, 6-TGN levels rose to above 235 pmol/8 ×10⁸ erythrocytes for 11 of the 14 patients. Conversely, the median 6-MMP level decreased from 6267 to 271 pmol/8 × 10⁸ erythrocytes (p = 0.001). Except for a 12% increase in mean corpuscular volume, no clinically significant changes in blood count were recorded. Notable infections were reported in 3 patients, and 1 patient had to discontinue treatment because of cytopenia. After 6 months, median prednisone daily dose was reduced by 74%, from 16.7 mg to 4.4 mg (p = 0.005), and 4 patients had been weaned off corticosteroids. Of the 14 patients, 11 (79%) were in full remission, and 2 (14%) were in partial remission.

Conclusion

Optimizing thiopurine therapy with an XOI may be a safe and effective strategy for patients with systemic autoimmune diseases.

Fabrication and characterization of dissolving microneedles for transdermal drug delivery of allopurinol

Allopurinol (AP) is the first line drug in treating hyperuricemia and gout in clinical by oral drug delivery, which is associated with severe adverse effects and the hepatic first-pass effect. Herein, we first proposed AP encapsulated dissolving microneedles (DMNs) for transdermal drug delivery to realize the sustained drug release and avoid the hepatic first-pass effect, which will help to reduce the adverse effects and improve the bioavailability of AP. DMNs were fabricated by a suspension solution casting method with precisely controlled dose. They had sufficient mechanical strength to penetrate through the skin and resulted in the formation of hundreds of micropores in skin. The results of in vitro and ex vivo release experiments demonstrated that the release profile of DMNs was independent with the dose of AP, and they indeed had much higher drug delivery efficiency (DDE) than the equal amount of AP in solutions. In vivo DDE reached to 38.9% within 1 h, and the drug residual can be served as a drug reservoir for sustained drug release. The result of pharmacodynamic study further confirmed that the sustained release and the anti-hyperuricemia effect of DMNs encapsulating AP were achieved. Moreover, transepidermal water loss significantly increased to 49.50 ± 3.82 g/m²·h after the application of DMNs and returned to normal levels (12.25 ± 0.21 g/m²·h) after 8 h, indicating that the DMNs were well tolerated. These results suggest that transdermal drug delivery of AP by using DMNs is an efficient and safe alternative to currently available routes of administration.

Effects of Hypothermia and Allopurinol on Oxidative Status in a Rat Model of Hypoxic Ischemic Encephalopathy

Hypoxic ischemic encephalopathy (HIE) is one of the main causes of morbidity and mortality during the neonatal period, despite treatment with hypothermia. There is evidence that oxidative damage plays an important role in the pathophysiology of hypoxic-ischemic (HI) brain injury. Our aim was to investigate whether postnatal allopurinol administration in combination with hypothermia would reduce oxidative stress (OS) biomarkers in an animal model of HIE. Postnatal 10-day rat pups underwent unilateral HI of moderate severity. Pups were randomized into: Sham operated, hypoxic-ischemic (HI), HI + allopurinol (HIA), HI + hypothermia (HIH), and HI + hypothermia + allopurinol (HIHA). Biomarkers of OS and antioxidants were evaluated: GSH/GSSG ratio and carbonyl groups were tested in plasma. Total antioxidant capacity (TAC) was analyzed in plasma and cerebrospinal fluid, and 8-iso-prostaglandin F2α was measured in brain tissue. Plasma 2,2′–azinobis-(3-ethyl-benzothiazoline-6-sulfonic acid) (ABTS) levels were preserved in those groups that received allopurinol and dual therapy. In cerebrospinal fluid, only the HIA group presented normal ferric reducing ability of plasma (FRAP) levels. Protein oxidation and lipid peroxidation were significantly reduced in all groups treated with hypothermia and allopurinol, thus enhancing neuroprotection in HIE.

Hyperuricemia and Progression of Chronic Kidney Disease: A Review from Physiology and Pathogenesis to the Role of Urate-Lowering Therapy

The relationship between hyperuricemia, gout, and renal disease has been investigated for several years. From the beginning, kidney disease has been considered a complication of gout; however, the viewpoints changed, claiming that hypertension and elevated uric acid (UA) levels are caused by decreased urate excretion in patients with renal impairment. To date, several examples of evidence support the role of hyperuricemia in cardiovascular or renal diseases. Several mechanisms have been identified that explain the relationship between hyperuricemia and chronic kidney disease, including the crystal effect, renin-angiotensin-aldosterone system activation, nitric oxide synthesis inhibition, and intracellular oxidative stress stimulation, and urate-lowering therapy (ULT) has been proven to reduce renal disease progression in the past few years. In this comprehensive review, the source and physiology of UA are introduced, and the mechanisms that explain the reciprocal relationship between hyperuricemia and kidney disease are reviewed. Lastly, current evidence supporting the use of ULT to postpone renal disease progression in patients with hyperuricemia and gout are summarized.

The major cardiovascular events of febuxostat versus allopurinol in treating gout or asymptomatic hyperuricemia: a systematic review and meta-analysis

BACKGROUND

To evaluate the major cardiovascular (CV) events of febuxostat compared to allopurinol for the treatment of gout or asymptomatic hyperuricemia.

METHODS

Relevant studies published until August 15, 2020 were identified by a systematic search of the PubMed and Wiley Online Library databases. Any controlled clinical trial, randomised controlled trial (RCT), retrospective cohort study or open label trial (OLT) comparing febuxostat in patients with gout or hyperuricemia with allopurinol. The quality of all identified studies was assessed based on Cochrane Collaboration's risk of bias tool. Odds ratios (OR) were calculated with random effects and reported with corresponding 95% confidence intervals (CI).

RESULTS

Eighteen studies were ultimately included in the analysis, among them 6 articles mentioned serum uric acid (sUA) level before and after treatment, 14 articles mentioned major cardiovascular events, 5 articles mentioned cardiovascular death, 6 articles mentioned skin reactions, 6 articles mentioned musculoskeletal and connective tissue signs and symptoms, 4 articles mentioned joint-related signs and symptoms, 6 articles mentioned upper respiratory infection, 5 articles mentioned gastrointestinal reaction and 7 articles mentioned all-cause mortality. The febuxostat group showed significantly lower sUA levels than allopurinol group (MD =-0.83, 95% CI: -1.22 to -0.44, P<0.0001, I2=98%). There was no markedly difference between the febuxostat and allopurinol (OR 1.01, 95% CI: 0.83 to 1.23, P=0.84, I2=95%) in the major cardiovascular events. The occurrence of skin reactions of febuxostat was significantly fewer than allopurinol (OR 0.55, 95% CI: 0.42 to 0.73, P<0.0001, I2=49%). Regarding to occurrence of CV death, musculoskeletal and connective tissue signs and symptoms, febuxostat group was higher than allopurinol group. However, among patients with gout or hyperuricemia, treatment with febuxostat resulted in other adverse reactions, including all-causes mortality similar to those associated with allopurinol.

DISCUSSION

The limitation of the study was the included studies show high heterogeneity in regard to their design. There was no difference in the incidence of major cardiovascular events between febuxostat and allopurinol, and febuxostat was better in lowering uric acid and has less adverse skin reactions than allopurinol, but the risk of CV death of febuxostat was higher than allopurinol.

Predominant HLA Alleles and Haplotypes in Mild Adverse Drug Reactions Caused by Allopurinol in Vietnamese Patients with Gout

Allopurinol (ALP) is commonly used as a drug for gout treatment. However, ALP is known to cause cutaneous adverse reactions (CARs) in patients. The HLA-B^*58:01 allele is considered a biomarker of severe CAR (SCAR) in patients with gout, with symptoms of Stevens Johnson syndrome, and with toxic epidermal necrolysis. However, in patients with gout and mild cutaneous adverse drug reactions (MCARs), the role of HLA-allele polymorphisms has not been thoroughly investigated. In this study, 50 samples from ALP-tolerant patients and ALP-induced MCARs patients were genotyped in order to examine the polymorphisms of their HLA-A and HLA-B alleles. Our results showed that the frequencies of HLA-A^*02:01/HLA-A^*24:02 and HLA-A^*02:01/HLA-A^*29:01, the dual haplotypes in HLA-A, in patients with ALP-induced MCARs were relatively high, at 33.3% (7/21), which was HLA-B^*58:01-independent, while the frequency of these dual haplotypes in the HLA-A locus in ALP-tolerant patients was only 3.45% (1/29). The HLA-B^*58:01 allele was detected in 38% (8/21) of patients with ALP-induced MCARs, and in 3.45% (1/29) of ALP-tolerant patients. Notably, although HLA-B^*58:01 may be a cause for the occurrence of MCARs in patients with gout, this correlation was not as strong as that previously reported in patients with SCAR. In conclusion, in addition to the HLA-B^*58:01 allele, the presence of the dual haplotypes of HLA-A^*02:01/HLA-A^*24:02 and/or HLA-A^*02:01/HLA-A^*29:01 in the HLA-A locus may also play an important role in the appearance of ALP-induced MCARs in the Vietnamese population. The obtained primary data may contribute to the development of suitable treatments for patients with gout not only in Vietnam but also in other Asian countries.

Effectiveness of Drug Treatments for Lowering Uric Acid on Renal Function in Patients With Chronic Kidney Disease and Hyperuricemia: A Network Meta-Analysis of Randomized Controlled Trials

Background: Hyperuricemia is very common in patients with chronic kidney disease (CKD); the role of hyperuricemia in the occurrence and progression of kidney disease remains an interesting and unresolved issue for nephrologists, and whether urate-lowering therapy (ULT) is warranted in CKD patients is still in controversy. To summarize and compare the clinical outcomes and adverse events (AEs) of three common ULT drugs, we performed a systematic review and network meta-analysis of randomized clinical trials (RCTs). Method: PubMed, MEDLINE, Clinical Trials.gov, EMBASE, and the Cochrane Central Register of Controlled Trials electronic databases were searched. The network meta-analysis was performed using the "gemtc 0.8-7" and its dependent packages in R software. The primary outcome was the change of renal function and uric acid; creatinine, proteinuria, blood pressure, and adverse events were assessed as the secondary outcomes. Results: 16 RCTs involving 1,943 patients were included in the final network analysis. Febuxostat, allopurinol, and benzbromarone were not found to exert superior effects over placebo upon renoprotective effect. With respect to lowering urate, the three drugs showed to be statistically superior to placebo, while febuxostat could better lower urate than allopurinol (MD: -1.547; 95% CrI: -2.473 to -0.626). It is also indicated that febuxostat was superior to placebo at controlling blood pressure, while no differences were observed when allopurinol and benzbromarone were compared to placebo. These results are stable in subgroup analysis. Conclusion: There is insufficient evidence to support the renoprotective effects of the three urate-lowering agents in CKD patients with hyperuricemia; febuxostat shows a tendency to be superior to allopurinol on lowering the decline of eGFR and increment of proteinturia, but the difference does not reach a statistical significance. Regarding its urate-lowering effect, febuxostat appears to be a satisfactory alternative to allopurinol and benzbromarone, and can control blood pressure better.

Allopurinol Protects Against Cholestatic Liver Injury in Mice Not Through Depletion of Uric Acid

Cholestasis is one of the most severe manifestations of liver injury and has limited therapeutic options. Allopurinol (AP), an inhibitor of uric acid (UA) synthesis, was reported to prevent liver damage in several liver diseases. However, whether AP protects against intrahepatic cholestatic liver injury and what is the role of UA in the pathogenesis of cholestasis remain unknown. In this study, we reported that AP attenuated liver injury in a mouse model of intrahepatic cholestasis induced by alpha-naphthylisothiocyanate (ANIT). AP showed no significant effect on glutathione depletion, inflammation, or bile acid metabolism in livers of ANIT-treated mice. Instead, AP significantly improved fatty acid β-oxidation in livers of ANIT-treated mice, which was associated with activation of PPARα. The protective effect of AP on cholestatic liver injury was not attributable to the depletion of UA, because both exogenous and endogenous UA prevented liver injury in ANIT-treated mice via inhibition of NF-kB-mediated inflammation. In conclusion, the present study provides a new perspective for the therapeutic use of AP and the role of UA in cholestatic liver injury.

Quality of care in people requiring hospital admission for gout in Aotearoa New Zealand: a nationwide analysis

AIMS

To understand national trends in hospital admission for a primary diagnosis of gout in Aotearoa New Zealand over the past 10 years and the quality of care for gout received by these patients before and after the admission.

METHODS

Data from the Aotearoa New Zealand National Collections from 1 January 2007 to 31 December 2019 were analysed to determine rates of hospital admission for a primary diagnosis of gout. Admission data including cost-weight analysis, as well as quality of care data including gout-specific medication dispensing in the year prior and year after admission.

RESULTS

There were 13,721 admissions with a primary diagnosis of gout over the analysis period, with an average cost per admission in 2019 of NZD 4,301. The rate of admission per 100,000 population was highest in Pacific peoples followed by MĀori. Although dispensing of any allopurinol increased in the year after admission, rates of regular allopurinol dispensing remained low; 38.1% for admissions in 2018. Patients who were younger (especially 20-44 years), not enrolled in a primary health organisation before admission, and female had lower rate of regular allopurinol after admission.

CONCLUSION

In this nationwide study, rates of admission for gout were highest in Pacific peoples and in MĀori. Rates of regular allopurinol dispensing was low even after admission for a primary diagnosis of gout. These findings highlight the need for improvements in gout management in Aotearoa New Zealand, including in post-discharge planning from secondary care inpatient services. This article is protected by copyright. All rights reserved.

Azathioprine-induced severe myelosuppression accompanied by massive hair loss and painful oral ulcer in an autoimmune hepatitis patient with NUDT15 minor variant: A case report

This report highlights azathioprine-induced severe myelosuppression in the patient with NUDT15 minor variant. This case report is particularly instructive because several typical symptoms are the clues to this critical adverse drug reaction.

Improving outcomes for patients hospitalised with gout: a systematic review

Objectives

Hospital admissions for gout flares have increased dramatically in recent years, despite widely available, effective medications for the treatment and prevention of flares. We conducted a systematic review to evaluate the effectiveness and implementation of interventions in patients hospitalized for gout flares.

Methods

A search was conducted in MEDLINE, Embase and the Cochrane library, from database inception to 8 April 2021, using the terms ‘gout’ and ‘hospital’ and their synonyms. Studies were included if they evaluated the effectiveness and/or implementation of interventions during hospital admissions or emergency department attendances for gout flares. Risk of bias assessments were performed for included studies.

Results

Nineteen articles were included. Most studies were small, retrospective analyses performed in single centres, with concerns for bias. Eleven studies (including five randomized controlled trials) reported improved patient outcomes following pharmacological interventions with known efficacy in gout, including allopurinol, prednisolone, NSAIDs and anakinra. Eight studies reported improved outcomes associated with non-pharmacological interventions: inpatient rheumatology consultation and a hospital gout management protocol. No studies to date have prospectively evaluated strategies designed to prevent re-admissions of patients hospitalized for gout flares.

Conclusion

There is an urgent need for high-quality, prospective studies of strategies for improving uptake of urate-lowering therapies in hospitalized patients, incorporating prophylaxis against flares and treat-to-target optimization of serum urate levels. Such studies are essential if the epidemic of hospital admissions from this treatable condition is to be countered.

Allopurinol ameliorates liver injury in type 1 diabetic rats through activating Nrf2

Hyperglycemia-induced oxidative stress plays important roles in the development of non-alcoholic fatty liver disease (NAFLD), which is a common complication in diabetic patients. The Nrf2-Keap1 pathway is important for cell antioxidant protection, while its role in exogenous antioxidant mediated protection against NAFLD is unclear. We thus, postulated that antioxidant treatment with allopurinol (ALP) may attenuate diabetic liver injury and explored the underlying mechanisms. Control (C) and streptozotocin (STZ)-induced diabetes rats (D) were untreated or treated with ALP for 4 weeks starting at 1 week after diabetes induction. Serum levels of alanine aminotransferase (ALT) and aspartate transaminase (AST), production of lipid peroxidation product malondialdehyde (MDA), and serum superoxide dismutase (SOD) were detected. Liver protein expressions of cleaved-caspase 3, IL-1β, nuclear factor-erythroid-2-related factor-2 (Nrf2), heme oxygenase-1 (HO-1), P62, Kelch-like ECH-associated protein 1 (Keap1), and LC3 were analyzed. In vitro, cultured rat normal hepatocytes BRL-3A were grouped to normal glucose (5.5 mM, NG) or high glucose (25 mM, HG) and treated with or without allopurinol (100 µM) for 48 h. Rats in the D group demonstrated liver injury evidenced as increased serum levels of ALT and AST. Diabetes increased apoptotic cell death, enhanced liver protein expressions of cleaved-caspase 3 and IL-1β with concomitantly increased production of MDA while serum SOD content was significantly reduced (all P < 0.05 vs C). In the meantime, protein levels of Nrf2, HO-1, and P62 were reduced while Keap1 and LC3 were increased in the untreated D group as compared to control (P < 0.05 vs C). And all the above alterations were significantly attenuated by ALP. Similar to our findings obtained from in vivo study, we got the same results in in vitro experiments. It is concluded that ALP activates the Nrf2/p62 pathway to ameliorate oxidative stress and liver injury in diabetic rats.

Cardiovascular Safety of Febuxostat and Allopurinol in Hyperuricemic Patients With or Without Gout: A Network Meta-Analysis

Background: Hyperuricemia is a common metabolic disease and has become a public health problem because of its increasing prevalence and association with comorbidities. Allopurinol and febuxostat are recommended as the first-line treatments for hyperuricemia and gout. But cardiovascular safety between febuxostat and allopurinol is still controversial. The purpose of this study is to compare the cardiovascular safety of XOIs and placebo in hyperuricemic patients with or without gout. Methods: PubMed, Embase via OVID, Cochrane Library, CNKI, Wanfang, and VIP were searched from their earliest records to February 8th 2021. ClinicalTrials.gov was also searched for unpublished data. The reference lists of included studies and relevant review articles investigating the cardiovascular safety of XOIs in hyperuricemia patients are screened for potentially eligible studies. Randomized controlled trials (RCTs) evaluating allopurinol (100~900 mg/d), febuxostat (20~120 mg/d), or placebo for hyperuricemia were included. The outcomes were incidence of MACE, non-fatal MI, non-fatal stroke, and cardiovascular death. We conducted a Bayesian random-effects network meta-analysis on the included randomized controlled trials using the Markov Chain Monte Carlo simulation method. The grading of recommendations assessment, development, and evaluation (GRADE) approach was used to assesses the certainty of the evidence. Results: Ten RCTs with 18,004 participants were included. The network estimates showed that there was no significant difference observed among febuxostat, allopurinol, and placebo regarding outcomes. The certainty of the evidence ranged from very low to moderate. The probabilities of rankings and SUCRA showed that compared to placebo, febuxostat, and allopurinol might prevent adverse cardiovascular events. Conclusion: Febuxostat is not associated with increasing risk of adverse cardiovascular events compared to allopurinol; and compared to placebo, whether febuxostat and allopurinol reduce the risk of adverse cardiovascular events remains uncertain.