Radiographic damage scores predict grip strength in patients with tophaceous gout

Intensive serum urate lowering with oral urate-lowering therapy for erosive gout: A randomized double-blind controlled trial

OBJECTIVE

To determine whether intensive serum urate lowering results in improved bone erosion scores in erosive gout.

METHODS

Two-year, double-blind, randomized, controlled trial of 104 participants with erosive gout on oral urate-lowering therapy (ULT) and serum urate ≥ 0.30mmol/L was undertaken. Participants were randomly assigned to serum urate target <0.20mmol/L (intensive target) or <0.30mmol/L (standard target, according to rheumatology guidelines). Oral ULT was titrated to target using a standardized protocol (using maximum approved doses of allopurinol, probenecid, febuxostat, and benzbromarone). The primary endpoint was total CT erosion score. OMERACT gout core outcome domains were secondary endpoints.

RESULTS

Although the serum urate was significantly lower in the intensive target group compared to the standard target group (P=0.002), fewer participants in the intensive group achieved the randomized serum urate target (at Year 2, 62% vs 83%, P<0.05). The intensive target group required higher allopurinol doses (mean (SD) 746 (210) mg/day vs 496 (185) mg/day, P<0.001), and used more combination therapy (P=0.0004). Small increases in CT erosion scores were observed in both groups over two years, with no between-group difference (P=0.20). OMERACT core outcome domains (gout flares, tophus, pain, patient global assessment, health-related quality of life, and activity limitation) improved in both groups, with no between-group differences. Adverse event and serious adverse event rates were similar between groups.

CONCLUSION

Compared with a serum urate target below 0.30mmol/L, more intensive serum urate-lowering is difficult to achieve with oral ULT, leads to high medication burden, and does not improve bone erosion scores in erosive gout.

Development of a radiographic scoring system for new bone formation in gout

Background

Features of new bone formation (NBF) are common in tophaceous gout. The aim of this project was to develop a plain radiographic scoring system for NBF in gout.

Methods

Informed by a literature review, scoring systems were tested in 80 individual 1st and 5th metatarsophalangeal joints. Plain radiography scores were compared with computed tomography (CT) measurements of the same joints. The best-performing scoring system was then tested in paired sets of hand and foot radiographs obtained over 2 years from an additional 25 patients. Inter-reader reproducibility was assessed using intraclass correlation coefficients (ICC). NBF scores were correlated with plain radiographic erosion scores (using the gout-modified Sharp-van der Heijde system).

Results

Following a series of structured reviews of plain radiographs and scoring exercises, a semi-quantitative scoring system for sclerosis and spur was developed. In the individual joint analysis, the inter-observer ICC (95% CI) was 0.84 (0.76–0.89) for sclerosis and 0.81 (0.72–0.87) for spur. Plain radiographic sclerosis and spur scores correlated with CT measurements (r = 0.65–0.74, P < 0.001 for all analyses). For the hand and foot radiograph sets, the inter-observer ICC (95% CI) was 0.94 (0.90–0.98) for sclerosis score and 0.76 (0.65–0.84) for spur score. Sclerosis and spur scores correlated highly with plain radiographic erosion scores (r = 0.87 and 0.71 respectively), but not with change in erosion scores over 2 years (r = −0.04–0.15).

Conclusion

A semi-quantitative plain radiographic scoring method for the assessment of NBF in gout is feasible, valid, and reproducible. This method may facilitate consistent measurement of NBF in gout.

Supplementary Information

The online version contains supplementary material available at 10.1186/s13075-021-02683-9.

Denosumab did not improve computerized tomography erosion scores when added to intensive urate-lowering therapy in gout: Results from a pilot randomized controlled trial

BACKGROUND/PURPOSE

Disordered osteoclast activity has been implicated in the pathogenesis of gouty bone erosion. We sought to determine if the addition of denosumab (a monoclonal antibody targeting the receptor activator of nuclear factor kappa-B ligand - RANKL) to intensive urate-lowering therapy (ULT) improves gouty bone erosion.

METHODS

Open-label, parallel-group pilot randomized controlled trial in which 20 participants with gout with at least one confirmed conventional radiographic foot bone erosion were assigned in a 1:1 allocation to receive denosumab (60 mg subcutaneous every 6 months) added to intensive ULT (serum urate ≤5 mg/dL or 300 µmol/L at the time of randomization and continued for the duration of the study), or intensive ULT alone. The primary outcome was the change in the bilateral foot and ankle computed tomography (CT) bone erosion score from baseline to 12 months, assessed by an experienced musculoskeletal radiologist blinded to study assignment. Secondary outcomes included change in serum C-terminal telopeptide (CTX), and patient reported outcomes of pain and function.

RESULTS

Although serum CTX declined markedly in the denosumab/ULT group compared with the ULT alone group, there was no interval change in CT erosion score in either the denosumab/ULT or ULT alone group after one year of follow-up. Other secondary outcomes did not differ between groups. There were two severe adverse events: One patient developed atrial fibrillation (on denosumab/ULT) and another atrial flutter (on ULT alone).

CONCLUSIONS

In this pilot study, denosumab did not offer additional benefit to intensive urate lowering therapy for gouty bone erosion.