Calcium Pyrophosphate Crystals In Synovial Fluid Research Articles

Association of mutations in hemochromatosis genes with clinical severity of calcium pyrophosphate arthritis

Aims: To study factors associated with the development of calcium pyrophosphate (CPP) arthritis and the severity phenotype. Methods: Transversal case-control study. Cases had to be confirmed by both X-ray chondrocalcinosis and CPP crystals in synovial fluid. Controls had neither chondrocalcinosis nor CPP crystals in synovial fluid. Patients and controls with hemochromatosis or primary hyperparathyroidism were not included. Mutations of hemochromatosis genes (HFE), magnesium (Mg), calcium (Ca), phosphate, iron (Fe), transferrin saturation, ferritin, parathyroid hormone (PTH), and calcifediol levels were studied. Results: Three hundred patients and 300 sex and age matched controls were compared. Lower serum Mg (sMg) and higher ferritin levels were found among patients. Hypomagnesemia (HypoMg) and HFE mutations were more frequent among patients. Involvement of over one joint was observed in 199 (66.4%) patients whereas persistent joint inflammation was retrieved in 154 (51.4%) of the patients. Initial analysis showed that the frequency of polyarticular and inflammatory phenotypes seemed to be progressively overrepresented in patients with HFE mutations. Further bivariate and multivariate analysis adjusted for the time from onset disclosed that the presence of genotypes with C282Y mutations was associated with polyarticular disease (hazard risk 3.501, 95% confidence interval 1.862–6.581, P < 0.001). Although C282Y mutations also seemed to be associated with inflammatory patterns, the association did not reach statistical significance (P = 0.173). Conclusions: Low sMg and high ferritin levels are associated with CPP arthritis (CPPA). In patients without hemochromatosis, HFE mutations, and specifically C282Y mutations seem to associate with the polyarticular disease phenotype, and plausibly with the chronic inflammatory phenotype.

Age-related features of calcium pyrophosphate deposition disease

Calcium pyrophosphate deposition disease (CPPD) is more common at an old age. The age-related features of the disease have not been studied. Objective : to study age-related features of CPPD. Subjects and methods . A total of 113 patients (54 men and 59 women) who had received inpatient or outpatient treatment at the V.A. Nasonova Research Institute of Rheumatology were retrospectively analyzed. The inclusion criteria were age older than 18 years, crystal-verified diagnosis of CPPD, and a signed informed consent. The patients were divided into two groups: 1) older than 55 years (n=38) and younger than 55 years (n=75). The investigators compared the frequency of clinical symptoms, including phenotypes in accordance with the EULAR recommendations, the intensity of pain with a visual analogue scale (VAS), the need for symptomatic therapy, detection rates for chondrocalcinosis (CC) in the knee and wrist joints by radiography, anthropometric and laboratory (the serum levels of C-reactive protein (CRP), creatinine, uric acid, parathyroid hormone, magnesium, phosphorus, and total calcium) features, the presence of CPPD-associated factors (a history of joint injuries, family CC cases, hypomagnesemia, hyperparathyroidism (HPT), hemochromatosis, hypomagnesemia, rheumatoid arthritis (RA), gout, chronic kidney disease (CKD) Stage >3, and use of diuretics). Results and discussion . Thirty-eight (33.6%) of the 113 examined patients with CPPD were aged less than 55 years. The most common clinical form of CPPD was chronic arthritis (n=54; 47.8%), the less common forms were osteoarthritis (OA) with calcium pyrophosphate (CPP) crystals (n=35; 31%) and acute arthritis (n=24; 21.2 %); their rates did not differ in the formed groups. In patients older than 55 years, the pain intensity according to VAS was higher than that at a younger age (50 [40; 70] mm and 40 [25; 54] mm, respectively; p 5 mg/dL was comparable for both groups. Family CPPD cases were recorded in two patients less than 55 years of age. Knee joint radiography significantly more frequently revealed CC in 65 (57.5%) patients aged older than 55 years than that at a younger age (68 and 36.8%, respectively; p=0.001). Hand radiography detected CC in 21 (18.6%) patients, it was also more common in those aged older than 55 years (25.3 and 5.3%, respectively; p=0.001). The CPPD-associated factors include OA, gout, HPT, RA, and CKD >3 Stage; these diseases detected in this study were seen in 91 (80.5%), 28 (24.8%), 14 (12.4%), 5 (4.4%), and 12 (11%) cases, respectively. There were no significant differences in the detection rates for these diseases in patients younger and older than 55 years of age. Also, one patient had hypomagnesemia and one patient had hemochromatosis; both were younger than 55 years old. Conclusion. The prevalence of CPPD at a young age can be underestimated: 33.6% of the patients with CPPD confirmed by the detection of CPP crystals in synovial fluid were aged less than 55 years. Moreover, the frequency of individual phenotypes and main CPPD-associated factors is identical in different age groups. At the age of older than 55 years, CPPD is characterized by the more frequent detection of radiographic signs of CC, a greater need for NSAIDs and colchicine, and a high level of CRP.

Comparison of ultrasonography and radiography of the wrist for diagnosis of calcium pyrophosphate deposition

ObjectiveUltrasound (US) seems a useful tool for diagnosis of calcium pyrophosphate (CPP) deposition (CPPD). We aimed to compare the performance of US and conventional radiography of the wrist for diagnosis of CPPD. MethodsPatients with CPP crystals identified in synovial fluid (SF) (knee, hip, shoulder, ankle or wrist) were consecutively included and compared to patients without CPP crystals in synovial fluid considered as controls. As recommended, we used the term chondrocalcinosis (CC) to assess imaging features suggesting CPPD. In all patients, US and radiographic assessment of CC of the wrists was performed by two distinct operators blinded each other (one operator by imaging modality). The two operators were blinded to clinical data, SF analysis and US or radiography findings. ResultsWe included 32 CPPD patients and 26 controls. Among CPPD patients, US revealed CC in 30 (93.7%) and radiography in 17 (53.1%) (P<0.001). The sensitivity and specificity of US for the diagnosis of CPPD were 94% and 85%, respectively; the positive likelihood ratio (LR+) was 6.1. The sensitivity and specificity of radiography were 53.1% and 100%, respectively. At joints level independently of SF analysis, US revealed CC in 35 joints without radiographic CC whereas X-rays showed CC in 3 joints without US CC. The κ coefficient between US and radiography for CC was moderate: 0.33 (0.171–0.408). ConclusionOur study suggests that wrist US should be considered as a relevant tool for the diagnosis of CPPD, with higher sensitivity than radiography for detecting CPP deposits.

SAT0535 Sensitivity and Reproducibility of Ultrasonography in Calcium Pyrophosphate Crystal Deposition: A Case-Control Study

BackgroundCalcium pyrophosphate disease (CPPD) is a common disease characterized by deposition of calcium pyrophosphate (CPP) crystals in joints and tendons. The diagnosis is made by identification of CPP crystal in...

AB0839 The Characteristic of Joint Involvement in Calcium Pyrophosphate Deposition Disease

BackgroundCalcium Pyrophosphate Deposition Disease (CPPD) is a metabolic disorder caused by calcium pyrophosphate (CPP) formation in joints. The diagnosis of CPPD is based on clinical manifestations and/or the presence of...

SAT0354 Usefulness of Imaging Techniques in Mixed Crystal Deposition (Pilot Study).

BackgroundThe coexistence of both urate and calcium pyrophosphate (CPP) crystals in the same synovial fluid has been reported by many authors. The evaluation of crystal deposits in mixed microcrystallic arthropathy...

Prevalence of calcium pyrophosphate and monosodium urate crystals in synovial fluid of patients with previously diagnosed joint diseases

ObjectiveThe main aim of this study was to investigate the frequency of monosodium urate (MSU) and calcium pyrophosphate (CPP) crystals in synovial fluid (SF) obtained from patients with previously diagnosed joint diseases. MethodsWe reviewed the results of SF analysis of 5020 samples identifying those collected from patients with a previously definite diagnosis (2370 samples). SF analysis results, age, sex, diagnosis and disease duration were recorded from computerized records of patients’ archives. ResultsThe prevalence of CPP crystals in SF was 22.28% in osteoarthritis (OA), 8.28% in rheumatoid arthritis (RA), 3.82% in psoriatic arthritis (PsA), 2.79% in other spondyloarthropathies (SpA), 10% in septic arthritis (SeA), 0.66% in gout and 9.18% in the miscellanea of joint diseases, respectively. The prevalence of MSU crystals in SF was 0.30% in RA, 3.34% in PsA, 0.70% in other SpA, 0.80% in acute CPP crystal arthritis (CPP-CA), 0% in OA, reactive arthritis (ReA), SeA, juvenile idiopathic arthritis (JIA) and miscellanea.In OA group, we observed that age and SF inflammatory indices were higher in SF positive to CPP crystals with respect to those without crystals (P<0.0001). In RA, we found that the group of patients with CPP crystals was significantly older (P=0.001) and had a SF less inflammatory (P=0.022) with respect to that without crystals but with a higher disease duration than those without crystals. ConclusionCrystals can be detected more frequently than expected in SF from joint diseases with a previous established diagnosis. This highlights the importance of SF analysis for the diagnosis of possible comorbidities linked to the presence of crystals.