The advancing role of ¹⁸F-FDG labeled autologous leukocytes PET/CT scan in patients with cardiac interventions and infections

Cardiac infections are difficult to detect on imaging. ¹⁸F-FDG PET/CT is a sensitive technique, however, variable physiological ¹⁸F-FDG uptake in the normal myocardium reduces its specificity and necessitates exhaustive patient preparation for the scan. ¹⁸F-FDG LAL PET/ CT, combining high sensitivity and specificity of radio-labeled leukocytes with excellent resolution of PET/CT, is useful in abdominal and skeletal infection imaging. ¹⁸F-FDG LAL PET/CT scans performed on patients for pacemaker and pacemaker lead infections, suspected post-Bentall's procedure infection, rheumatic heart disease (RHD) post valve replacement, cardiac transplant with stent graft infection, infective endocarditis, vascular graft infection and abdominal aorta mycotic aneurysm infection. Blood culture was considered the gold standard; if it was negative, overall clinical, biochemical, and radiological investigations were used to assess concordance with the ¹⁸F-FDG LAL PET/CT scan. ¹⁸F-FDG LAL PET/CT showed a sensitivity of 91.3% false negative (likely due to prolonged antibiotic course before the scan) and 2/30 (6.67%) false positive results. ¹⁸F-FDG LAL PET/CT was concordant in 86.6 % of patients with overall diagnosis based on clinical, biochemical, and radiological features. Within the different sub-groups, the highest sensitivity (100%) and specificity (100%) were found in patients with infective endocarditis. The results of this initial study indicate that ¹⁸F-FDG LAL PET/CT is a reliable non-invasive imaging technique to accurately localize and direct medical or surgical intervention in patients with suspected cardiac infection