Systemic lupus erythematosus and gouty arthritis: an uncommon association

Nutritional, biochemical, and clinical determinants of hyperuricemia in systemic lupus erythematosus patients: Relationship with clinical and renal disease activity

Systemic lupus erythematosus (SLE) is the prototypical autoimmune disease considered as an independent risk factor for mortality by cardiovascular disease. Currently, uric acid is described as a novel biomarker associated with cardiometabolic risk. However, nutritional and serum determinants that influence hyperuricemia development in autoimmune diseases have not been fully elucidated. This study aimed to assess the nutritional, biochemical, and cardiometabolic determinants of hyperuricemia and its relationship with clinical variables in SLE patients. A cross-sectional study was conducted in 167 SLE patients and 195 control subjects (CS). Nutrient intake, anthropometry, biochemical, and cardiometabolic indexes were evaluated. In SLE patients, adequate protein (OR = 0.4; p = 0.04) and carbohydrate (OR = 0.2; p = 0.01) intakes were associated with a lower risk of hyperuricemia. SLE patients with hyperuricemia presented a higher risk of clinical (OR = 2.2; p = 0.03) and renal activity (OR = 3.4; p < 0.01), as well as triglycerides ≥150 mg/dL (OR = 3.6; p < 0.01), hs-CRP ≥1 mg/L (OR = 3.1; p < 0.01), Kannel score ≥3 (OR = 2.5; p = 0.02), and BMI ≥25 kg/m² (OR = 2.2; p = 0.02). Oppositely, serum levels of HDL-C ≥40 mg/dL (OR = 0.2; p < 0.01) were associated with a lower risk of hyperuricemia. According to the pharmacotherapy administered, prednisone treatment was associated with a high risk of hyperuricemia (OR = 4.7; p < 0.001). In contrast, the hydroxychloroquine treatment was associated with a lower risk of hyperuricemia (OR = 0.4; p = 0.02). In conclusion, SLE patients with hyperuricemia presented a high risk of clinical and renal activity as well as worse cardiometabolic status. Notably, an adequate intake of protein, carbohydrates, healthy HDL-C serum levels, and hydroxychloroquine treatment could be determinants of lower risk of hyperuricemia.

Efficacy and safety of gout flare prophylaxis and therapy use in people with chronic kidney disease: a Gout, Hyperuricemia and Crystal-Associated Disease Network (G-CAN)-initiated literature review

Gout flare prophylaxis and therapy use in people with underlying chronic kidney disease (CKD) is challenging, given limited treatment options and risk of worsening renal function with inappropriate treatment dosing. This literature review aimed to describe the current literature on the efficacy and safety of gout flare prophylaxis and therapy use in people with CKD stages 3-5. A literature search via PubMed, the Cochrane Library, and EMBASE was performed from 1 January 1959 to 31 January 2018. Inclusion criteria were studies with people with gout and renal impairment (i.e. estimated glomerular filtration rate (eGFR) or creatinine clearance (CrCl) < 60 ml/min/1.73 m²), and with exposure to colchicine, interleukin-1 inhibitors, non-steroidal anti-inflammatory drugs (NSAIDs), and glucocorticoids. All study designs were included. A total of 33 studies with efficacy and/or safety analysis stratified by renal function were reviewed-colchicine (n = 20), anakinra (n = 7), canakinumab (n = 1), NSAIDs (n = 3), and glucocorticoids (n = 2). A total of 58 studies reported these primary outcomes without renal function stratification-colchicine (n = 29), anakinra (n = 10), canakinumab (n = 6), rilonacept (n = 2), NSAIDs (n = 1), and glucocorticoids (n = 10). Most clinical trials excluded study participants with severe CKD (i.e. eGFR or CrCl of < 30 mL/min/1.73 m²). Information on the efficacy and safety outcomes of gout flare prophylaxis and therapy use stratified by renal function is lacking. Clinical trial results cannot be extrapolated for those with advanced CKD. Where possible, current and future gout flare studies should include patients with CKD and with study outcomes reported based on renal function and using standardised gout flare definition.

Low expression of estrogen receptor β in renal tubular epithelial cells may cause hyperuricemia in premenopausal patients with systemic lupus erythematosus

We investigated the impact of estrogen receptor (ER) expression in renal tubular epithelial cells on serum uric acid (UA) levels in premenopausal patients with systemic lupus erythematosus (SLE). Thirty patients underwent renal biopsy: 18 with SLE (LN group) and 12 with IgA nephritis (IgAN group). ERs (ERα and ERβ) in renal tubular epithelial cells were measured using immunohistochemistry. The ER expression levels of the two groups were compared, and the relationship between the expression of ERs and serum UA levels was analyzed. Mean serum UA levels in the LN group were significantly higher than those of the IgA nephropathy group, while the mean creatinine levels and GFRs of the two groups were similar. Pathological changes in the LN group were significantly more severe than those in the IgAN group. ERβ was expressed in renal tubular epithelial cells in both groups, but not in the glomeruli. ERβ expression in the LN group was significantly lower than that in the IgAN group. ERβ expression scores significantly negatively correlated with serum UA levels. These findings suggest that the expression of ERβ in premenopausal female SLE patients may cause hyperuricemia, and may subsequently promote glomerular damage, suggesting that ERβ may be involved in UA excretion.

Pregnancy-related complications and risk of postpartum readmission for seizures and epilepsy: A national study

OBJECTIVE

Peripartum seizures remain a leading cause of maternal morbidity and mortality worldwide. Therefore, recognition of high-risk individuals is essential. We aimed to determine the rate and identify risk factors for postpartum seizure/epilepsy readmissions.

METHODS

In this retrospective cohort study, the Nationwide Readmissions Database was used to identify index admissions for delivery and readmissions for seizures in the year 2013, defined by International Classification of Disease, Ninth Revision, Clinical Modification codes for epilepsy, convulsions, and eclampsia in the primary diagnostic position. Logistic regression analysis was used to examine 30-day readmission for seizures as well as associations between demographic, medical, psychiatric, and pregnancy-related factors.

RESULTS

There were 1 633 714 index admissions for delivery, with a 30-day readmission rate for seizures/epilepsy of 19.69 per 100 000 index admissions. The mean age of index participants was 28.6 years (SD = 5.8). Postpartum 30-day readmissions for eclampsia represented 80% of seizure/epilepsy readmissions. Higher income was associated with lower odds of seizure/epilepsy readmission (odds ratio [OR] = 0.50, 95% confidence interval [CI] = 0.34-0.72, P = .03) for the highest income group. Eclampsia (OR = 19.9, 95% CI = 9.38-42.2, P < .001), preexisting epilepsy (OR = 10.63, 95% CI = 6.43-17.56, P < .001), pre-eclampsia (OR = 3.23, 95% CI = 2.31-4.51, P < .001), and gestational hypertension (OR = 2.78, 95% CI = 1.94-3.98, P < .001) were associated with readmission for seizures.

SIGNIFICANCE

Readmissions for seizures are fortunately rare, but are important to minimize given morbidity and mortality. Most seizure readmissions occurring within 30 days postpartum were coded as eclampsia rather than convulsions or pre-existing epilepsy. These findings suggest that early identification of women with pre-eclampsia and eclampsia may play a role in the prevention of postpartum seizures. Women with these risk factors should be identified to optimize care and monitored closely for seizure-associated complications.

The coexistence of gout in ankylosing spondylitis patients: a case control study

Ankylosing spondylitis (AS) and gout are common inflammatory arthropathies. It had been claimed previously that the two conditions rarely coexist. The aim of this study was to compare the prevalence of gout in a population of AS patients to its prevalence in the general population. To conduct this population-based case-control study, data of adult patients with a physician diagnosis of AS were retrieved from the database of the largest health-care provider organization in Israel, Clalit Health Services. For each patient with AS, five age- and sex-matched subjects without AS were randomly selected from the same database. Different parameters including the existence of gout, hypertension, body mass index, socioeconomic status, and smoking were evaluated in both the AS and the control groups. The study included 3763 patients with AS and 19,214 controls. The proportion of gout in the AS group was higher than in the control group: 73 subjects in the AS group had gout, while only 107 subjects in the non-AS group had gout (1.94% and 0.56%, respectively, OR 3.53, P < 0.001). Logistic regression adjusting for possible confounding variables found that AS was independently associated with gout (OR 1.41, P = 0.037). Our study suggests that gout is not less common in AS patients in comparison with the general population, and that it might even be more common in AS patients.

Levels of uric acid may predict the future development of pulmonary hypertension in systemic lupus erythematosus: a seven-year follow-up study

OBJECTIVE

The objective of this paper is to assess whether pulmonary hypertension (PH) may be detected at one point in time or longitudinally predicted by serum uric acid (sUA) levels in systemic lupus erythematosus (SLE).

METHODS

We conducted a post-hoc analysis of a long-term followed cohort of Mexican SLE patients. Echocardiography-based definitions of PH by the ESC/ERS/ISHLT and its associations with clinical and laboratory data on enrollment were studied. Especially, the impact that sUA levels at baseline may have on the future development of PH in patients with normal pulmonary artery systolic pressure (PASP) was explored.

RESULTS

Out of the 156 SLE patients originally enrolled in the cohort, 44 met the inclusion criteria for the present study and were grouped as having (n =10) or not having (n = 34) PH. At baseline, sUA levels of 5.83 ± 1.79 and 5.82 ± 1.97 mg/dl (p = ns) were found in patients with and without PH, respectively. No association between PASP and other markers was found. In patients with normal PASP, the presence of sUA ≥ 7 mg/dl at baseline predicted future development of PH (relative risk 8.5, 1.0009 to 72; p = 0.04).

CONCLUSION

In SLE, sUA levels at one point in time are useless to detect PH. However, steady hyperuricemia may predict the future development of PH in patients with normal PASP at baseline.

Correlation of asymptomatic hyperuricaemia and serum uric acid levels with arterial stiffness in women with systemic lupus erythematosus without clinically evident atherosclerotic cardiovascular disease

The objective of this article was to evaluate whether serum uric acid (SUA) correlates with arterial stiffness and inflammation markers in a cohort of women with systemic lupus erythematosus (SLE) without overt atherosclerotic cardiovascular diseases, who attended a community hospital. One hundred and two women with SLE were assessed as part of this cross-sectional study. Carotid-femoral pulse wave velocity (PWV) was measured using an automatic device (Complior). C-reactive protein (CRP), fibrinogen and homocysteine levels as well as other metabolic results were recorded. Duration and activity of SLE, damage accrual and treatments were recorded. SLE women were categorized as having or not having hyperuricaemia (HU) according to SUA levels (greater than or up to 6.2 mg/dl, respectively). A multiple linear regression analysis was used to determine the independent link between SUA levels and other variables. Women with SLE and HU (n = 15, 15%) had a worse cardiovascular risk profile that included ageing, hypertension, obesity, higher total cholesterol levels, renal failure and presence of metabolic syndrome. Also, the duration of SLE was increased and damage accrual was greater. In the unadjusted analysis, SUA levels correlated with PWV, CRP, fibrinogen and homocysteine. However, in a multivariate linear regression analysis, SUA levels independently correlated with the duration of SLE, creatinine, total cholesterol and homocysteine levels but did not correlate with PWV. In conclusion, SUA was associated with arterial stiffness, but not independently of age and homocysteine levels. Nevertheless, SUA might be an ancillary indicator of subclinical atherosclerosis in SLE women without clinically evident atherosclerotic cardiovascular disease.