Polymyalgia rheumatica (PMR) and giant cell arteritis (GCA) are closely related chronic inflammatory diseases. Glucocorticoids (GCs) are first-choice drugs for PMR and GCA, although some patients show poor responsiveness to the initial GC regimen or experience flares after GC tapering. To date, no valid biomarkers have been found to predict which patients are at most risk for developing GC resistance. In this review, we summarize PMR- and GCA-related gene polymorphisms and we associate these gene variants with GC resistance and therapeutic outcomes. A limited number of GC resistance associated-polymorphisms have been published so far, mostly related to HLA-DRB1*04 allele. Other genes such ICAM-1, TLR4 and 9, VEGF, and INFG may play a role, although discrepancies are often found among different populations. We conclude that more studies are required to identify reliable biomarkers of GC resistance. Such biomarkers could help distinguish non-responders from responders to GC treatment, with concomitant consequences for therapeutic strategy.

• Klíčová slova
• giant cell arteritis, glucocorticoid resistance, pharmacogenetics, polymyalgia rheumatica,
• Publikační typ
• časopisecké články MeSH
• přehledy MeSH

Polymyalgia rheumatica (PMR) is one of the inflammatory rheumatic diseases that can potentially be detected by positron emission tomography/CT. High fluorine-18 fludeoxyglucose (18F-FDG) accumulation around the shoulders, sternoclavicular and hip joints are the most common pre-treatment features of patients with PMR. Another common sign is increased 18F-FDG uptake in extra-articular regions between columnal spinous processes, near ischial tuberosities and in the praepubic area. Some patients also present with high 18F-FDG uptake in main arteries, corresponding to the characteristics of giant cell arteritis. It is possible to observe a decrease or even a disappearance of 18F-FDG uptake after effective therapy, an event which may be useful for the monitoring of treatment as well as for detection of PMR relapse.

• MeSH
• fluorodeoxyglukosa F18 * MeSH
• kyčelní kloub diagnostické zobrazování   MeSH
• lidé MeSH
• PET/CT metody   MeSH
• polymyalgia rheumatica diagnostické zobrazování   MeSH
• radiofarmaka * MeSH
• ramenní kloub diagnostické zobrazování   MeSH
• sternoklavikulární kloub diagnostické zobrazování   MeSH
• Check Tag
• lidé MeSH
• Publikační typ
• časopisecké články MeSH
• přehledy MeSH
• Názvy látek
• fluorodeoxyglukosa F18 * MeSH
• radiofarmaka * MeSH

BACKGROUND: The role of 18F-fluorodeoxyglucose positron emission computed tomography (18F-FDG PET/CT) is increasing in the diagnosis of polymyalgia rheumatica (PMR), one of the most common inflammatory rheumatic diseases. In addition to other locations, increased 18F-FDG accumulation has been detected in the praepubic region in some patients. However, a deeper description and pathophysiological explanation of this increased praepubic accumulation has been lacking. The aim of the presented study is to confirm a decrease in praepubic 18F-FDG accumulation in response to therapy and to describe potential correlations to other 18F-FDG PET/CT scan characteristics during the course of disease. As a secondary objective, we describe the pathological aspects of the observed praepubic 18F-FDG uptake. PATIENTS AND METHODS: A retrospective review of patients with newly suspected PMR undergoing baseline and follow up 18F-FDG PET/CT between February 2010 and March 2016 is given. Those with a visually detected presence of praepubic 18F-FDG accumulation were further analysed. The uptake was assessed visually and also semi-quantitatively in the defined region of interest by calculation of target-to-liver ratios. Other regions typical for PMR were systematically described as well (shoulders, hips, sternoclavicular joints, ischiogluteal bursae, spinous interspaces). RESULTS: Twenty-three out of 89 screened patients (26%) presented with initial praepubic 18F-FDG PET/CT positivity, 15 of whom also underwent follow up 18F-FDG PET/CT examination. Five out of 15 patients presented with increased 18F-FDG accumulation in large arteries as a sign of giant cell arteritis. During follow up examination, decrease in 18F-FDG accumulation caused by therapeutic intervention was observed in all evaluated locations in all analysed patients and no new positivity was indicated, including periarticular, extraarticular tissues or target large vessels. Praepubical accumulation of 18F-FDG was diminished in all patients (15/15, 100%) after treatment with steroids. CONCLUSIONS: Increased praepubic 18F-FDG uptake in patients with PMR is relatively common and this region should be systematically evaluated during differential diagnosis of rheumatic and malignant disease. Praepubic inflammation is probably related to enthesitis and tenosynovitis at the origin of pectineus and adductor longus muscles ventrally from the pubis.

• Klíčová slova
• enthesitis, fluorodeoxyglucose, polymyalgia rheumatica, positron emission tomography, tenosynovitis,
• Publikační typ
• časopisecké články MeSH

• MeSH
• fluorodeoxyglukosa F18 farmakologie   MeSH
• lidé MeSH
• počítačová rentgenová tomografie * MeSH
• pozitronová emisní tomografie * MeSH
• vaskulitida diagnóza   diagnostické zobrazování   MeSH
• Check Tag
• lidé MeSH
• ženské pohlaví MeSH
• Publikační typ
• dopisy MeSH
• komentáře MeSH
• práce podpořená grantem MeSH
• Názvy látek
• fluorodeoxyglukosa F18 MeSH