Atteinte rénale au cours de la spondylarthrite ankylosante

Relative risk of end-stage renal disease requiring dialysis in treated ankylosing spondylitis patients compared with individuals without ankylosing spondylitis: A nationwide, population-based, matched-cohort study

Objective

To examine the relative risk of end-stage renal disease (ESRD) requiring dialysis among treated ankylosing spondylitis (AS) patients compared with non-AS individuals.

Methods

We used claims data from Taiwan’s National Health Insurance Research Database obtained between 2003 and 2012, and enrolled 37,070 newly treated AS patients and randomly selected 370,700 non-AS individuals matched (1:10) for age, sex and year of index date. Those with a history of chronic renal failure or dialysis were excluded. After adjusting for age, sex, diabetes mellitus, hypertension, IgA nephropathy, frequency of serum creatinine examinations, use of methotrexate, sulfasalazine, ciclosporis, corticosteroid, aminoglycoside, amphotericin B, cisplatin, contrast agents and annual cumulative defined daily dose (cDDD) of traditional NSAIDs, selective cyclooxygenase-2 inhibitors (COX-2i) and preferential COX-2i, we calculated the adjusted hazard ratios (aHRs) with 95% confidence intervals using the Cox proportional hazard model to quantify the risk of ESRD in AS patients. We re-selected 6621 AS patients and 6621 non-AS subjects by further matching (1:1) for cDDDs of three groups of NSAIDs to re-estimate the aHRs for ESRD.

Results

Fifty-one (0.14%) of the 37,070 AS patients and 1417 (0.38%) of the non-AS individuals developed ESRD after a follow-up of 158,846 and 1,707,757 person-years, respectively. The aHR for ESRD was 0.59 (0.42–0.81) in AS patients compared with non-AS individuals. However, after further matching for cDDD of NSAIDs, the aHR of ESRD was 1.02 (0.41–2.53). Significant risk factors included hypertension, IgA nephropathy and use of COX-2i.

Conclusions

The risk of ESRD was not significantly different between treated AS patients and non-AS individuals matched for age, sex, year of index date and dose of NSAID.

Spondyloarthritis Patients Suffer Increased Risk of Renal Complications Compared With General Population: A Retrospective Observational Study

The objective of this study was to identify the prevalence and risk factors of renal complications of spondyloarthritis (SpA) patients, and to assess increased risks compared to general people. We conducted a retrospective study enrolled with consecutive SpA patients from an inpatient department and age, sex-matched general population (GP). The renal disorders investigated in this study contained decreased estimated glomerular filtration rate (eGFR), hematuria, proteinuria and nephrolithiasis. A total of 350 admitted SpA patients with complete medical records and 323 age and sex-matched GP were enrolled. Most SpA patients were male (n = 283, 80.9%) and the mean age was 31.61 ± 10.73 years old. Among 350 SpA patients, 29 (8.8%) suffered from hematuria, six (1.8%) suffered from proteinuria, one (0.3%) had decreased eGFR, and 27 (13.0%) presented with nephrolithiasis. The relative risk (RR) of nephrolithiasis in SpA compared to the GP was 2.24 (95% CI, 1.00-4.98), and the RR of renal insufficiency was 2.04 (95% CI, 1.11-3.77). In a univariate analysis, nephrolithiasis was significantly associated with age, age of onset, smoking, extra-articular manifestation and a bamboo spine. Renal insufficiency was significantly associated with age, peripheral manifestation, serum albumin, C-reactive protein and erythrocyte sedimentation rate. In a multivariable analysis, only extra-articular manifestation (OR = 8.43, 95% CI, 1.65-43.06, p = 0.010) and bamboo spine (OR = 3.47, 95% CI, 1.01-12.06, p = 0.049) remained significantly associated with nephrolithiasis. However, no variable was recognized as an independent risk factor for renal insufficiency. Renal complications are more common in SpA patients, with more than two-fold increased risk compared with GP. Extra-articular manifestation and bamboo spine are independent risk factors of renal disease in SpA patients.

The Prevalence of Renal Impairment in Patients with Spondyloarthritis: Results from the International ASAS-COMOSPA Study

OBJECTIVE

To assess the prevalence and association of renal dysfunction in patients with spondyloarthritis (SpA).

METHODS

The ASAS-COMOSPA (Assessment of Spondyloarthritis international Society-COMOrbidities in SPondyloArthritis) was an international study (22 participating countries from 4 continents) investigating comorbidities in SpA. Renal function was assessed based on estimated glomerular filtration rate (eGFR) calculated using the Modification of Diet in Renal Disease equation. SpA characteristics and risk factors for renal impairment were collected. Nonsteroidal antiinflammatory drug (NSAID) use was assessed based on current intake (last 3 mos).

RESULTS

Of the 3984 patients recruited, 2098 (52.6%) were analyzed after excluding outliers and patients with no available eGFR measurement [male sex: 63.5%; age: 45.3 yrs; disease duration: 8.6 years; HLA-B27+: 73.1%; Bath Ankylosing Spondylitis Activity Index (BASDAI): 3.6/10]. Overall, 153 patients (5.2%, mean age: 53.6 yrs) exhibited an eGFR < 60 ml/min/1.73 m2. In univariate analysis, renal impairment was associated with age (p < 0.001), HLA-B27 positivity (p = 0.003), several cardiovascular (CV) risk factors (history of hypertension, p < 0.001; systolic blood pressure, p = 0.009; diabetes, p = 0.005; and Framingham risk score, p < 0.001), disease activity scores [BASDAI, p = 0.001; Ankylosing Spondylitis Disease Activity Score-C-reactive protein (ASDAS-CRP), p < 0.001], functional variables (Bath Ankylosing Spondylitis Functional Index, p < 0.001), inflammatory biomarkers (erythrocyte and CRP, both p < 0.001), and NSAID intake since onset of disease (percentage of days, p = 0.008). However, there was no association with disease duration, disease severity, or ASAS-NSAID score. In multivariate analysis, age (45-59 yrs: OR 1.9, > 60 yrs: OR 6.2), HLA-B27 positivity (OR 0.51), and CRP (OR 1.3) remained significantly associated with eGFR < 60 ml/min/1.73 m2.

CONCLUSION

Renal impairment was associated with age, HLA-B27 positivity, and inflammation, though not with CV risk factors, disease severity, or NSAID intake in patients with SpA.

Prevalence and risk factors for osteoporosis and fractures in axial spondyloarthritis: A systematic review and meta-analysis

OBJECTIVES

To describe the prevalence of osteoporosis, the prevalence and incidence of fractures, and the frequency of risk factors for low bone mineral density (BMD) in axial spondyloarthritis (Ax-SpA).

METHODS

A systematic review and meta-analysis of observational studies was conducted. Medline, Embase, and Cochrane Library databases were searched with a sensitive strategy. Large cross-sectional and longitudinal studies published in the last 10 years (January 2006-2016) with representative samples of patients with Ax-SpA estimating the frequency of osteoporosis, risk factors or fractures were selected.

RESULTS

After screening 3597 titles and abstracts, 46 studies were reviewed in detail, of which 35 studies had a cross-sectional design, 5 were prospective and 6 retrospective; 21 studies compared Ax-SpA patients with a control group-either healthy individuals (18 studies) or subjects with other diseases (6 studies). The prevalence of osteoporosis varied from 11.7% to 34.4% and that of fractures from 11% to 24.6%. Alcohol intake (58-61%), use of corticosteroids (11.7-66.9%), and 25-OH vitamin D deficiency (26-76%) were unexpectedly high in Ax-SpA patients.

CONCLUSION

The prevalence of osteoporosis and fractures in Ax-SpA varies between 11.7% and 34.4% and 11-24.6%, respectively. Alcohol intake, steroid use, and low levels of 25-OH-vitamin D should be taken into account in osteoporosis assessment in patients with Ax-SpA. Inconsistent results, lack of bone quality assessment, and high likelihood of bias of the published studies confirm the need for performing well-designed studies.

Membranous nephropathy in a patient with ankylosing spondylitis: A case report

RATIONALE

Renal complications in ankylosing spondylitis (AS) were rarely observed, and proteinuria associated with AS can be seen often due to amyloidosis in this kind of complications, while membranous nephropathy (MN) is seldom considered. This article reports a case of coexistence of AS and MN, to provide the exact relationship of these 2 entities and recognized some causes of renal involvement in AS.

PATIENT CONCERNS

A 44-year-old female presented with pain of the left leg for 4 years and pedal edema for 2 weeks.

DIAGNOSES

AS was diagnosed according to the patient's clinical manifestation and sacroiliitis observed on computed tomography (CT) scan. Nephrotic syndrome was found and MN was diagnosed according to kidney biopsy in which thickened capillary loops were observed with light microscopy, granular deposits of IgG along the capillary wall were observed using immunofluorescence staining, and subepithelial electron-dense deposits were observed with electron microscopy. No other secondary causes of MN were found on extensive investigations.

INTERVENTION

Given the diagnoses, the patient received nonimmunosuppressive therapy for MN and adalimumab for AS.

OUTCOMES

The patient got pain relief, as well as urinary protein reduction.

LESSONS

This case suggested a secondary MN in association with AS and the relationship between these 2 diseases needed more concern and further illumination.

MEFV M694V mutation has a role in susceptibility to ankylosing spondylitis: A meta-analysis

OBJECTIVE

The aim of the current study was to determine the contributions of several common mutations in the Mediterranean fever (MEFV) gene, namely, E148Q, M680I, M694V and V726A, to ankylosing spondylitis (AS) susceptibility.

METHODS

Two investigators independently searched the literature regarding the association of MEFV with AS in the PubMed, EMBASE, Web of Science, and Scopus databases. They independently selected eligible articles and then extracted data from the included studies. The associations between MEFV mutations and AS risk were assessed with odds ratios (ORs) and 95% confidence intervals (95% CI). Further analyses were conducted with STATA 12.0 software (Stata Corp.; College Station, Texas, USA).

RESULTS

Four mutations (E148Q, M680I, M694V and V726A) were genotyped in 869 AS cases and 879 controls from the 8 eligible studies. Of the four mutations, M694V (pooled OR: 3.330, 95% CI: 2.129-5.208) was found to be associated with AS through overall analysis. However, the other mutations demonstrated no relation with AS (pooled ORs: 1.295, 1.258, 1.778; 95% CI: 0.886-1.891, 0.688-2.298 and 0.938-3.371). No significant publication bias was discovered in the meta-analysis.

CONCLUSIONS

The present study indicates that the MEFV M694V mutation may contribute to the pathogenesis of AS. The associations between the other mutations and AS need to be validated with more relevant and well-designed studies.

Short-Term Non-Steroid Anti-Inflammatory Drug Use in Spondyloarthritis Patients Induces Subclinical Acute Kidney Injury: Biomarkers Study

BACKGROUND

Non-steroid anti-inflammatory drug (NSAID) usage is associated with kidney injury. Rise in serum creatinine (sCr) often represents irreversible process. Thus to assess the early effects of regular NSAID use, we studied sensitive serum and urine biomarkers of kidney injury.

METHODS

In a protocol-based intervention study, 103 subjects were enrolled in 3 mutually exclusive groups. Group 1 included 37 healthy controls having minimal baseline NSAID exposure as per a definition, and group 2 had 41 spondyloarthritis (SpA) patients on regular NSAID therapy for >3 months. Group 3 included 25 SpA patients having minimal NSAID exposure at baseline. Blood and urine samples were collected from all the 3 groups at baseline. Furthermore, group 3 was started on 6-week regular NSAID therapy, and blood and urine samples were re-collected at 1, 6, and 12 weeks. Baseline normal kidney function as per the definition was ensured in all the subjects. Creatinine, neutrophil gelatinase-associated lipocalin (NGAL), kidney injury molecule-1 (KIM-1), cystatin-C, and microalbumin were measured in urine and serum samples to assess kidney injury.

RESULTS

Kidney injury biomarkers were 2-3-fold higher in SpA patients using regular NSAID therapy compared to healthy controls and SpA patients having minimal NSAID exposure (uKIM-1 and uNGAL p < 0.0001, sKIM-1 and sNGAL p = 0.001). There was no difference in sCr and estimated glomerular filtration rate using Cockcroft-Gault equation between the groups. In SpA patients started on 6 weeks of regular NSAID (group 3), biomarker levels started rising at week 1 and showed a significant rise at week 6. The levels in the patients that stopped NSAID use at 6 weeks showed reversibility at 12 weeks.

CONCLUSIONS

Regular NSAID use in SpA patients induces subclinical kidney injury represented by rise in biomarkers. These levels start rising as early as 7 days of regular NSAID use and are reversible on stopping the drug.