A predictive tool for an effective use of F-18-FDG PET in assessing activity of sarcoidosis

作者：Mostard Remy L M; Van Kuijk Sander M J; Verschakelen Johny A; van Kroonenburgh Marinus J P G; Nelemans Patty J; Wijnen Petal A H M; Drent Marjolein^*

来源：BMC Pulmonary Medicine, 2012, 12: 57.

DOI：10.1186/1471-2466-12-57

• Clinical prediction rule
• High-resolution computed tomography
• Soluble interleukin-2 receptor
• PET
• Sarcoidosis

Background: F-18-FDG PET/CT (PET) is useful in assessing inflammatory activity in sarcoidosis. However, no appropriate indications are available. The aim of this study was to develop a prediction rule that can be used to identify symptomatic sarcoidosis patients who have a high probability of PET-positivity. %26lt;br%26gt;Methods: We retrospectively analyzed a cohort of sarcoidosis patients with non organ specific persistent disabling symptoms (n = 95). Results of soluble interleukin-2 receptor (sIL-2R) assessment and high-resolution computed tomography (HRCT) were included in the predefined model. HRCT scans were classified using a semi-quantitative scoring system and PET findings as positive or negative, respectively. A prediction model was derived based on logistic regression analysis. We quantified the model%26apos;s performance using measures of discrimination and calibration. Finally, we constructed a prediction rule that should be easily applicable in clinical practice. %26lt;br%26gt;Results: The prediction rule showed good calibration and good overall performance (goodness-of-fit test, p = 0.78, Brier score 20.1%) and discriminated between patients with positive and negative PET findings (area under the receiver-operating characteristic curve, 0.83). If a positive predictive value for the presence of inflammatory activity of %26gt;= 90% is considered acceptable for clinical decision-making without referral to PET, PET would be indicated in only 29.5% of the patients. Using a positive predictive value of 98%, about half of the patients (46.3%) would require referral to PET. %26lt;br%26gt;Conclusions: The derived and internally validated clinical prediction rule, based on sIL-2R levels and HRCT scoring results, appeared to be useful to identify sarcoidosis patients with a high probability of inflammatory activity. Using this rule may enable a more effective use of PET scan for assessment of inflammatory activity in sarcoidosis.

• 出版日期2012-9-14