Retrospective Study Comparing WBC scan and 18F-FDG PET/CT in Patients with Suspected Prosthetic Vascular Graft Infection

Abstract

WHAT THIS PAPER ADDS This study is the second and the largest to compare 18 F-fluoro-D-glucose (FDG) positron emission tomography/ computed tomography (PET/CT) and white blood cell scan in the diagnosis of prosthetic vascular graft infections (PVGIs). The white blood cell scan was more accurate than 18 F-FDG PET/CT. Moreover, there was only one false negative 18 F-FDG PET-CT result under antibiotic therapy. Nuclear imaging results should be included in the diagnostic criteria for prosthetic vascular graft infections. Computed tomography angiography still remains the first radiological examination to perform when there is suspicion of PVGI. A white blood cell scan should be considered for patients with a suspicion of prosthetic vascular graft infection and negative or equivocal computed tomography angiography results. If a white blood cell scan is not readily available, 18 F-FDG PET/CT can be performed. If the result is negative, prosthetic vascular graft infections can be ruled out thanks to a good negative predictive value. However, a positive result should be interpreted with caution, especially for thrombosed grafts. Objectives: Prosthetic vascular graft infections (PVGIs) are associated with high mortality rates. To improve treatment outcome, an early and definite diagnosis is critical, and current diagnostic criteria are often insufficient. The accuracy of 2-deoxy-2-[fluorine-18]-fluoro-D-glucose positron emission tomography integrated with computed tomography (18 F-FDG PET/CT) and white blood cell (WBC) scan for the diagnosis of PVGI were compared. Methods: A retrospective single centre study was conducted on patients undergoing WBC scan and 18 F-FDG PET/ CT for a suspected PVGI between

Evidence-based guideline of the European Association of Nuclear Medicine (EANM) on imaging infection in vascular grafts

“…In this study, CT showed high number of false negative scans both in early infections, where the findings were wrongly interpreted as post-surgical changes, and in late infections, where CT did not show any alteration [ 43 ]. In another recent comparative study by Puges et al, radiolabelled WBC scan showed higher accuracy than [ 18 F]FDG PET/CT, even in patients under antibiotic treatment and in thrombosed graft infection [ 44 ].…”

“…For this PICO, 73 papers were retrieved but only 3 studies were finally selected [ 22 , 43 , 44 ]. However, no studies directly comparing patients with and without antibiotic treatment for VGEI exist.…”

(The Role of PET/CT in Angiology)

“…Jak zmíněno výše, přínos FDG PET/CT v diagnostice infekce chirurgických cévních náhrad byl hodnocen řadou studií. [18][19][20][21][22][23][24][25][26][27][28][32][33][34][35][36][37] Separátní data, která by analyzovala přínos FDG PET/CT v diagnostice infekcí stentgraftu (SGI) po EVAR, jsou však v literatuře vzácná, výše uvedené studie jsou provedeny na populacích výhradně s chirurgickými protézami, popř. na populacích smíšených (tedy pacientů s VG spolu s pacienty po EVAR), extrahovat údaje o SGI lze jen výjimečně (např.…”

“…V přímém porovnání diagnostické přesnosti FDG PET/CT a WBC na smíšeném kolektivu vykázala WBC pro diagnózu VGI signifi kantně vyšší diagnostickou přesnost. 37 Parametry diagnostické přesnosti při "per--graft" analýze byly při porovnání FDG PET/CT vs. WBC: senzitivita 85 % vs. 90 % a specifi cita 68 % vs. 91 %. V práci Erba a spol.…”

One Year on: Test Your Knowledge From June 2019

“…Which statements are correct among the following regarding the radiological diagnosis of prosthetic vascular graft infection (PVGI)? 14 A. Computed tomography angiography (CTA) has a good sensitivity in low-grade infections B. Nuclear imaging exams should be performed first, before CTA C. 18F-FDG PET/CT has a good specificity for infections diagnosis D. White blood cell scan has a better accuracy than 18F-FDG PET/CT for PVGI diagnosis E. Positive 18F-FDG PET/CT results should be interpreted with caution in thrombosed grafts.…”