Gout Urate Cryst. Depos. Dis., Volume 4, Issue 3 (September 2026) – 3 articles

Gout is a systemic metabolic inflammatory disease driven by hyperuricemia and monosodium urate crystal deposition, and is frequently accompanied by chronic kidney disease and uric acid nephrolithiasis. Current evidence indicates that acidic urine, hypocitraturia, and insufficient ammonium excretion are common in gout patients, and may be associated with insulin resistance, impaired renal ammoniagenesis, and abnormalities in tubular acid-base regulation. Persistent urinary acidification may contribute to the development and progression of uric acid stone formation and gout-related renal injury by reducing uric acid solubility, promoting crystal formation and intratubular deposition, and decreasing renal uric acid clearance. Urinary alkalization therapy can increase urine pH, thereby enhancing uric acid solubility and excretion, and has shown potential in some studies to improve serum urate levels, proteinuria, renal function parameters, and gout flare frequency, especially when using citrate-based alkali. However, the currently available evidence is mainly derived from observational studies and small prospective investigations, and recommendations across international guidelines remain inconsistent. High-quality evidence is still lacking regarding the optimal target population, urine pH range, choice of alkalizing agents, monitoring strategies, and long-term efficacy. Well-designed prospective studies are therefore needed to clarify the clinical role of urinary alkalization in renal protection among patients with gout. Full article

Background and Objectives: Despite evidence demonstrating the advantages of rheumatology-led point-of-care (POC) polarised light microscopy (PLM), it remains underutilised in many hospital settings. We aimed to identify barriers to its use and assess typical caseloads of crystal arthropathy, diagnostic methods and frequency of rheumatology-led POC PLM in practice in Ireland. We also assessed reliance on laboratory-led crystal analysis and the turnaround time for results to be reported. Solutions to improve implementation of rheumatologist-led POC PLM were also explored. Material and Methods: We surveyed 29 rheumatologists registered to the Irish Society of Rheumatology via SurveyMonkey, between May and October 2024. Textual responses were categorised into key themes, and word clouds were generated using Tagcrowd to visualise thematic content. Results: Fifty-five percent of respondents faced challenges using POC PLM for crystal analysis. Common barriers included lack of access to a microscope, lack of a polarising light function and lack of training in performing and interpreting of PLM. Fifty-two percent of rheumatologists highlighted the critical need for accessible and functional microscopes. Ninety-two percent of respondents relied on in-house laboratory crystal analysis. Thirty-two percent received inaccurate or incomplete results from laboratory reports and 28% of respondents reported delays in sample analysis from the laboratory. Laboratory turnaround was 1–2 days for 43% of rheumatologists and 3–5 days for 33%. Sixty-nine percent had not received training on PLM and 48% emphasised the need for improved education on POC PLM, including improved integration into the national rheumatology training. Conclusions: Rheumatology-led POC PLM remains underutilised despite its clinical advantage primarily due to equipment and training deficits. Addressing these barriers through improved infrastructure, education and equipment is essential to ensure effective and timely care for patients with crystal arthropathy. Full article

Calcific tendinitis (CT) is a condition that most commonly affects the rotator cuff tendons of the shoulder joint. Fundamental crystal morphology and composition underlying different radiological stages of CT remained insufficiently characterized. We collected human tendon samples from 33 patients with CT and 12 control patients. CT patients exhibited an increased incidence of comorbidities, especially high blood pressure and disorders of fat metabolism. Based on the Gärtner classification, calcific deposits were classified as type I in two patients, type II in 14 patients, and type III in 17 patients. Tendon calcification of the controls was significantly lower compared to the CT group. No differences in the amount of histological calcification between the Gärtner groups were observed. A correlation between the radiological size of calcification and the amount of calcification detected in histology was found. SEM-EDS and Raman identified basic calcium phosphate to be the predominant crystal type in tendons from CT patients, with only two calcium pyrophosphate detections. CT is mainly associated with BCP deposition. Calcified depot size was associated with pain intensity, while diabetes mellitus was observed more frequently in CT patients than in controls. BCP may be a focus of future mechanistic studies on CT. Full article