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We looked for predicting factors for the detection of infectious foci on 18F-fluorodeoxyglucose-positron emission tomography in combination with computed tomography (FDG PET/CT) among patients with Staphylococcus aureus bacteremia (SAB) who participated in an interventional study that was conducted at Rambam Health Care Campus, between July 1, 2015 and February 1, 2019. The primary outcome was an infectious focus detected by FDG PET/CT. Independent predictors for detection of focal infection were identified using univariate followed by a logistic regression multivariate analysis. We included 149 patients with 151 separate episodes of SAB who underwent FDG-PET/CT. Focal infections were detected in 107 patients (70.8%). Independent predictors for focal infection detection were community acquisition of bacteremia with odds ratio (OR) 3.03 [95% confidence interval (CI) 1.04–8.77], p-0.042 and C reactive protein (CRP) with OR 1.09 [95% CI 1.04–1.14], p < 0.001. Primary bacteremia was inversely associated with focal infection detection with OR 0.27 [0.10–0.69], p = 0.007, as were the pre-scan blood glucose levels OR 0.9 [0.98–0.99], p-0.004. The latter stayed significant in the subgroup of patients with diabetes mellitus. To conclude, patients with community-acquired bacteremia or high CRP levels should be carefully investigated for focal infection. Patients who present with primary bacteremia seem to be at low risk for focal infection. [ABSTRACT FROM AUTHOR]

Objective: Neoadjuvant chemoradiotherapy (CMRT) is the most effective treatment of stage III non-small-cell lung cancer (NSCLC). The present study aimed at assessing FDG PET/CT for defining the response of N2 disease to neoadjuvant CMRT, as surgical resection after such therapy significantly improves 5-year survival in responding N2 disease.Methods: Forty-five patients with locally advanced NSCLC underwent both pre-neoadjuvant therapy FDG PET/CT and post-neoadjuvant therapy FDG PET/CT followed by anatomical resection of lung and ipsilateral mediastinal lymph nodes (LN). Seventeen of these patients who had PET/CT studies in our institution and were operated after CMRT were retrospectively included in the study group (12 males, ages 43-78 years; stage IIIA: 14 patients, stage IIIB: 3 patients). PET/CT response in N2 was visually scored per-lymph node station and per patient. Quantitative N2 response was evaluated by SUVmax and total lesion glycolysis (TLG) measurements after therapy alone and in comparison with pre-therapy values. PET/CT N2 response was confirmed at surgery.Results: Seventeen NSCLC patients with 29 metastatic N2 lymph nodes (LN) were assessed. Histopathology confirmed 14 responders and 3 non-responders, and was available in 20/29 metastatic LN, showing complete response in 17 and residual disease in 3 LN. LN-based visual analysis of N2 response on PET/CT defined 3 TP, 16 TN and 1 FP, for sensitivity, specificity, accuracy, negative and positive predictive values (NPV and PPV) of 100, 94, 95, 100 and 75%, respectively. Patient-based visual analysis defined 3 TP, 13 TN and 1 FP study, for sensitivity, specificity, accuracy, NPV and PPV of 100, 93, 94, 100 and 75%, respectively. Nodal-based quantitative analysis of FDG uptake in N2 nodes revealed a significant difference between responding and non-responding LN only of SUVmax post-therapy (2.5 ± 1.21 vs. 3.5 ± 2.36, P = 0.04).Conclusion: FDG PET/CT after neoadjuvant therapy accurately defined response in metastatic N2 nodes of NSCLC patients, presenting very high sensitivity and NPV for detecting responding nodes. PET/CT may enable selection of candidates for curative resection of stage III NSCLC. Mediastinoscopy may not be mandatory in patients with a negative PET/CT after neoadjuvant therapy. [ABSTRACT FROM AUTHOR]

Purpose: Fluoro-deoxyglucose positron emmission tomography combined with computed tomography (FDG-PET/CT) is superior to iliac bone marrow biopsy (iBMB) for detection of bone marrow involvement (BMI) in staging of Hodgkin's lymphoma (HL). The present study aims to characterize the patterns and distribution of BMI in HL as determined by FDG-PET/CT. Methods: Reports of FDG-PET/CT studies performed for staging of HL were reviewed. BMI was defined as positive iBMB and/or foci of pathological FDG uptake in the skeleton that behaved in concordance with other sites of lymphoma in studies following chemotherapy. Number of FDG uptake foci, their specific location in the skeleton and the presence of corresponding lesions in the CT component of the study, and stage according to the Ann Arbor staging system, were recorded. Results: The study included 473 patients. iBMB was performed in 336 patients. Nine patients had positive iBMB (9/336, 3 %). Seventy-three patients (73/473, 15 %) had FDG-PET/CT-defined BMI. The BM was the only extranodal site of HL in 52/473 patients (11 %). Forty-five patients had three or more foci of pathological skeletal FDG uptake (45/73, 62 %). Sixty-four patients (64/73, 88 %) had at least one uptake focus in the pelvis or vertebrae. In 60 patients (60/73, 82 %), the number of skeletal FDG uptake foci without corresponding CT lesions was equal to or higher than the number of foci with morphological abnormalities. Conclusion: FDG-PET/CT demonstrated BMI in 15 % of patients with newly diagnosed HL. Diagnosis of BMI in HL by FDG-PET/CT was more sensitive than iBMB with potential upstage in 11 % of patients. The most common pattern of FDG-PET/CT BMI was multifocal (at least three foci) skeletal FDG uptake, with at least one focus in the pelvis or vertebrae and no corresponding CT lesions. [ABSTRACT FROM AUTHOR]

Purpose: Osteomyelitis, the most serious complication of the diabetic foot, occurs in about 20 % of patients. Early diagnosis is crucial. Appropriate treatment will avoid or decrease the likelihood of amputation. The objective of this study was to assess the value of FDG PET/CT in diabetic patients with clinically suspected osteomyelitis. Methods: Enrolled in this prospective study were 39 consecutive diabetic patients (29 men and 10 women, mean age 57 years, range 28-71 years) with 46 suspected sites of foot infection. Of these 39 patients, 38 had type 2 and 1 type 1 diabetes for 4-25 years, and 28 were receiving treatment with insulin. FDG PET/CT was interpreted for the presence, intensity (SUVmax) and localization of increased FDG foci. Final diagnosis was based on histopathology and bacteriology of surgical samples, or clinical and imaging follow-up. Results: Osteomyelitis was correctly diagnosed in 18 and excluded in 21 sites. Of 20 lesions with focal bone FDG uptake, 2 were false-positive with no further evidence of osteomyelitis. Five sites of diffuse FDG uptake involving more than one bone on CT were correctly diagnosed as diabetic osteoarthropathy. FDG PET/CT had a sensitivity, specificity and accuracy of 100 %, 92 % and 95 % in a patient-based analysis and 100 %, 93 % and 96 % in a lesion-based analysis, respectively, for the diagnosis of osteomyelitis in the diabetic foot. Conclusion: FDG PET/CT was found to have high performance indices for evaluation of the diabetic foot. The PET component identified FDG-avid foci in sites of acute infection which were precisely localized on fused PET/CT images allowing correct differentiation between osteomyelitis and soft-tissue infection. [ABSTRACT FROM AUTHOR]

To evaluate whether PET/low-dose CT (ldCT) using 18F-fluorodeoxyglucose (FDG) improves characterization of indeterminate single pulmonary nodules (SPNs) in patients at high risk of lung cancer. Retrospective analysis of 307 patients who underwent FDG-PET/CT for indeterminate SPNs identified 93 (70 men, age range 46–90 years) at high risk of lung cancer (age >40 years, minimum 10 pack-year smokers). SPNs were evaluated for the presence and intensity of FDG avidity and ldCT patterns. The performance of visual and semiquantitative FDG-PET/ldCT algorithms for characterization of SPNs was compared to that of ldCT. Incongruent FDG-PET and ldCT patterns were analyzed for significance in further patient management. Malignancy was diagnosed in 38% patients. FDG avidity defined 33 SPNs as true-positive (TP) and 2 as false-negative (FN) (malignant), and 41 as true-negative (TN) and 17 as false-positive (FP) (benign). For SUVmax of 2.2 (by ROC analysis) there were 27 TP, 8 FN, 48 TN and 10 FP SPNs. LdCT defined 34 TP, 1 FN, 28 TN and 30 FP lesions. Of the FP lesions on ldCT, 60% were FDG-negative. Visual PET/ldCT analysis had a sensitivity of 94%, a specificity of 70%, an accuracy of 80%, a positive predictive value (PPV) of 66%, and a negative predictive value (NPV) of 95% as compared to 77%, 83%, 81%, 73%, 86% for semiquantitative PET/ldCT and 97%, 48%, 66%, 53%, 96% for ldCT, respectively. Both PET/ldCT algorithms had statistically significantly higher specificity and accuracy than ldCT. Semiquantitative analysis showed significantly higher PPV and lower sensitivity and NPV than found with ldCT. A single screening procedure encompassing FDG-PET and ldCT may improve screening for lung cancer in high-risk patients. The significantly improved specificity may potentially reduce FP ldCT results and further unnecessary invasive procedures. [ABSTRACT FROM AUTHOR]

We report a case of acute sacroiliitis with severe disability after only 3 weeks of isotretinoin therapy with graduate reduction of pain, limitation and muscle incompetence after discontinuation of the drug and ACTH-depo injection and Ethodolac therapy. Naranjo probability scale indicated a probable relationship between isotretinoin therapy and bilateral sacroiliitis. We discussed possible mechanisms of sacroiliitis and disability due to isotretinoin treatment. [ABSTRACT FROM AUTHOR]