Diagnostic modalities in sarcoidosis: BAL, EBUS, and PET.
Advances have been made in minimally invasive diagnostic procedures in sarcoidosis, including bronchoalveolar lavage (BAL), endobronchial ultrasonography-guided transbronchial needle aspiration (EBUS-TBNA), and positron emission tomography (PET). Several independent groups found almost identical predictive values of the CD4:CD8 ratio in BAL for the diagnosis of sarcoidosis. A CD4:CD8 ratio greater than 3.5 shows a high specificity of 93 to 96% for sarcoidosis, but the sensitivity is low (53 to 59%). EBUS-TBNA is a safe and useful tool for diagnosing sarcoidosis stage I and II with a sensitivity of 83 to 93% and a specificity of 100%. Novel imaging techniques have been explored, such as PET using L-[3- (18)F] fluoro-alpha-methyltyrosine ( (18)F-F MT), which is more specific for malignancy than (18)F-fluorodeoxyglucose ( (18)F-FDG)-PET. The combined modality of FMT-PET with FDG-PET could successfully discriminate sarcoidosis from malignancy. These recent developments including novel biopsy procedures and novel imaging techniques could be of value to diagnosing sarcoidosis.
Costabel
Ulrich
U
Medical Faculty, University of Duisburg-Essen, Department of Pneumology/Allergy, Ruhrlandklinik, Essen, Germany. ulrich.costabel@ruhrlandklinik.uk-essen.de
Bonella
Francesco
F
Ohshimo
Shinichiro
S
Guzman
Josune
J
D001707:Biopsy, Needle / Q000379:methods; D018893:Bronchoalveolar Lavage / Q000379:methods; D016516:CD4-CD8 Ratio / Q000379:methods*; D006801:Humans; D049268:Positron-Emission Tomography / Q000379:methods*; D011237:Predictive Value of Tests; D012507:Sarcoidosis / Q000175:diagnosis* / Q000473:pathology; D012680:Sensitivity and Specificity; D018084:Ultrasonography, Interventional / Q000379:methods