Limb arteries involvement assessed by FDG/PET CT at diagnosis of giant cell arteritis and risk of relapse: An observational study.

INTRODUCTION: Steroids and anti-IL6 biotherapy are highly effective in obtaining remission in patients with giant cell arteritis (GCA) but the risk of relapses remains high. We aimed to identify predictors of relapse in GCA. METHODS: All consecutive patients admitted with a new diagnosis of GCA - according to the 2022 American College of Rheumatology/EULAR (ACR/EULAR) classification criteria - between May 2011 and May 2022 were eligible for this study. The primary outcome was the GCA relapse rate over the 36-months follow up. Factors associated with the primary outcome and time to first relapse were analyzed. RESULTS: One hundred and eight patients (74 [69-81] years, 64.8% women) with a new diagnosis of GCA were studied. GCA was biopsy-proven in 65 (60.2%) cases. Ninety-eight (90.7%) FDG/PET CT scans performed at diagnosis were available for review. All patients received steroids given for 21.0 [18.0-28.5] months, associated with methotrexate (n=1, 0.9%) or tocilizumab (n=2, 1.9%). During a median follow-up of 27.5 [11.4-35.0] months, relapse occurred in 40 (37%) patients. Multivariable Cox regression model, including general signs, gender, aortic wall thickness, FDG uptake in arterial wall and IV steroid pulse as covariates, showed that both general signs (HR 2.0 [1.0-4.0, P<0.05) and FDG uptake in limb arteries (HR 2.7 [1.3-5.5], P<0.01) at diagnosis were associated with GCA relapse. CONCLUSION: FDG uptake in limb arteries at diagnosis is a predictor of relapse in newly diagnosed GCA.

Prognosis and follow-up of patients with prosthetic valve endocarditis treated conservatively in relation to WBC-SPECT imaging.

BACKGROUND: Our objective was to evaluate in patients with prosthetic valve endocarditis (PVE) treated conservatively, the prognostic value of white blood cell (WBC) signal intensity on SPECT and to describe the evolution of the WBC signal under antibiotics. METHODS: Patients with PVE treated conservatively and positive WBC-SPECT imaging were identified retrospectively. Signal intensity was classified as intense if equal to or higher, or mild if lower, than the liver signal. Clinical, biological, imaging and follow-up information were collected from medical files. RESULTS: Among 47 patients, WBC signal was classified as intense in 10 patients and as mild, in 37. The incidence of the primary composite endpoint (death, late cardiac surgery, or relapse) was significantly higher in patients with intense vs. mild signal (90% vs. 11%). Twenty-five patients underwent a second WBC-SPECT imaging during follow-up. The prevalence of WBC signal decreased progressively from 89% between 3 and 6 weeks to 42% between 6 and 9 weeks and 8% more than 9 weeks after initiation of antibiotics. CONCLUSIONS: In patients with PVE treated conservatively, intense WBC signal was associated with poor outcome. WBC-SPECT imaging appears as an interesting tool for risk stratification and to monitor locally the efficacy of antibiotic treatment.

FDG PET/CT Imaging of Sarcoidosis.

Sarcoidosis is a multisystemic granulomatous disease of unknown etiology. The diagnostic can be made by histological identification of non-caseous granuloma or by a combination of clinical criteria. Active inflammatory granuloma can lead to fibrotic damage. Although 50% of cases resolve spontaneously, systemic treatments are often necessary to decrease symptoms and avoid permanent organ dysfunction, notably in cardiac sarcoidosis. The course of the disease can be punctuated by exacerbations and relapses and the prognostic depends mainly on affected sites and patient management. FDG-PET/CT along with newer FDG-PET/MR have emerged as key imaging modalities in sarcoidosis, namely for certain diagnostic purposes, staging and biopsy guiding. By identifying with a high sensitivity inflammatory active granuloma, FDG hybrid imaging is a main prognostic tool and therapeutic ally in sarcoidosis. This review aims to highlight the actual critical roles of hybrid PET imaging in sarcoidosis and display a brief perspective for the future which appears to include other radiotracers and artificial intelligence applications.

Musculoskeletal Tuberculosis: New Insights on Diagnosis Strategy and Treatment.

BACKGROUND/ OBJECTIVE: Skeletal tuberculosis (TB) is rare. We aimed to report on diagnostic strategy and treatment of skeletal TB. METHODS: In this multidisciplinary single-center medical records review study, all adult patients admitted between January 2009 and December 2019 with microbiologically proven skeletal TB were included. Demographic, medical history, laboratory, imaging, pathologic findings, treatment, and follow-up data were extracted from medical records. RESULTS: Among 184 patients identified with TB, 21 (16 women, 42 years [27, 48 years]) had skeletal involvement. Skeletal TB included spondylitis (n = 11), lytic bone lesions (n = 7), sacroiliitis (n = 5), arthritis (n = 3), osteitis (n = 2), and diffuse muscle abscesses without bone lesion (n = 1). Lytic lesions involved both axial and peripheral skeleton at multiple sites in most cases. 18F-fluorodeoxyglucose positron emission tomography was performed in 13 patients and helped to detect multifocal asymptomatic lesions and to target biopsy. All patients were treated with anti-TB therapy for 7 to 18 months. Fifteen patients (71.4%) received steroids as an adjunct therapy. Eleven patients needed an orthopedic immobilization corset, and 3 patients underwent surgery. All patients clinically improved under treatment, but 2 relapsed over a median follow-up of 24 months (12-30 months). No patient died or suffered long-term disabilities. CONCLUSION: Our study emphasizes the diversity of skeletal involvement in TB. 18F-fluorodeoxyglucose positron emission tomography scanner at diagnosis is key to assess the extension of skeletal involvement and guide extraskeletal biopsy. Neurological complications might be prevented by adding corticosteroids to anti-TB therapy.

Diagnosis and staging of cardiac masses: additional value of CMR with 18F-FDG-PET compared to CMR with CECT.

PURPOSE: Characterization of malignant cardiac masses is usually performed with cardiac magnetic resonance (CMR) and staging with whole-body contrast-enhanced computed tomography (CECT). In this study, our objective was to evaluate the role of 18Fluor-fluorodeoxyglucose positron emission tomography (18F-FDG-PET) with CMR for both characterization and staging of cardiac masses. METHODS: Patients with cardiac masses who underwent CMR, CECT, and 18F-FDG-PET were retrospectively identified. For the characterization of cardiac masses, we calculated the respective performances of CMR alone, 18F-FDG-PET alone, and the combination of 18F-FDG-PET and CMR. For staging, we compared head-to-head the respective performances of 18F-FDG-PET and CECT. Histology served as gold standard for malignancy, and response to anticoagulation for thrombus. RESULTS: In a total of 28 patients (median age 60.5 years, 60.7% women), CMR accurately distinguished malignant from benign masses with sensitivity (Se) of 86.7%, specificity (Sp) of 100%, positive predictive value (PPV) of 100%, negative predictive value (NPV) of 86.7%, and accuracy of 92.9%. 18F-FDG-PET demonstrated 93.3% Se, 84.6% Sp, 87.5% PPV, 91.7% NPV, and 89.3% accuracy. Combining CMR with 18F-FDG-PET allowed to benefit from the high sensitivity of 18F-FDG-PET (92.9%) and the excellent specificity of CMR (100%) for malignant diseases. For staging, 18F-FDG-PET outperformed CECT on per-patient (66.7% vs 55.6% correct diagnosis, respectively), per-organ (10 vs 7 organs, respectively), and per-lesion basis (> 29 vs > 25 lesions, respectively). CONCLUSION: Combining 18F-FDG-PET with CMR improved the characterization of cardiac masses compared to each modality alone. Additionally, the diagnostic performance of 18F-FDG-PET was better than CECT for staging. This study suggests that the combination of CMR and 18F-FDG-PET is the most effective for the characterization of cardiac masses and the staging of these lesions.

Diagnostic performance of White Blood Cell SPECT imaging against intra-operative findings in patients with a suspicion of prosthetic valve endocarditis.

AIM: The objective of this study was to evaluate the diagnostic performance of white blood cells (WBC)-SPECT imaging in patients with suspicion of prosthetic valve endocarditis (PVE) against intra-operative findings. METHODS: 36 consecutive patients who underwent cardiac surgery 30 days after WBC-SPECT imaging were identified retrospectively. Clinical, imaging, and biological results were collected from reports. WBC-SPECT results were classified as positive or negative and, if positive, the intensity of signal graded as intense or mild. Lesions observed during cardiac surgery were collected from surgeons' reports. RESULTS: The 20 patients with positive WBC-SPECT study had confirmed PVE intra-operatively. Patients with intense signal on WBC-SPECT had high prevalence of abscesses (83%) compared to patients with only mild signal (12%). The three patients with negative WBC-SPECT but confirmed PVE had longer duration of antibiotic treatment before imaging and had no perivalvular abscess. Sensitivity, specificity, positive predictive and negative values, and accuracy of WBC-SPECT were measured at 87%, 100%, 100%, 81%, and 92%, respectively. Addition of WBC-SPECT results to the modified Duke score helped re-classify correctly 25% of patients from possible to definite PVE. CONCLUSION: In patients with suspicion of PVE, WBC-SPECT imaging provides excellent diagnostic performance against intra-operative findings.

Squamous cell carcinoma of the tongue with cardiac metastasis on 18F-FDG PET/CT: A case report and literature review.

INTRODUCTION: The most common malignancies metastasizing to the heart are cancers of the lung, breast, mesothelioma, melanoma, leukemia, and lymphoma. Cardiac metastasis from a tongue cancer is a rare finding and only a few cases have been reported previously in the literature. In this case report and literature review, we discuss the main clinical features of patients with cardiac metastases secondary to a tongue cancer and imaging modalities performed, especially the 18F-Fluorodeoxyglucose positron emission tomography/computed tomography (18F-FDG PET/CT). PATIENT CONCERNS: This is a case of a 39-year-old woman who in April 2018 was diagnosed with an invasive well differentiated squamous cell carcinoma of the movable tongue. She underwent a left hemiglossectomy followed by a revision of hemiglossectomy and ipsilateral selective neck lymph nodes dissection levels II to III because of pathological margins. An early inoperable clinical recurrence was diagnosed and she received radiochemotherapy with good clinical and metabolic response. She remained asymptomatic thereafter. DIAGNOSIS: In January 2020, a pre-scheduled 18F-FDG PET/CT showed a diffuse cardiac involvement. In February 2020, a biopsy of the lesion revealed a metastatic squamous cell carcinoma. INTERVENTIONS: She was deemed to not be a cardiac surgical candidate and treated by palliative chemotherapy: taxol-carboplatin associated with cetuximab then cetuximab alone because of adverse effects. A re-evaluation imaging performed in April 2020 evidenced a progression of the cardiac involvement, which led to switch chemotherapy by immunotherapy with nivolumab. OUTCOMES: This patient had a very poor prognosis and succumbed to major heart failure 4 months after the diagnosis of cardiac metastasis. CONCLUSION: In this case report, 18F-FDG PET/CT proved to be useful in detecting cardiac metastasis and changed the therapeutic management of the patient. It suggests that patients with tongue malignancies in a context of poor initial prognosis should be followed-up early by 18F-FDG PET/CT with HFLC diet to facilitate detection of recurrence.

Management of patients with myocardial tuberculosis: A case series.

BACKGROUND: Myocardial Tuberculosis (MT) is exceedingly rare. We aimed to report on myocardial involvement in tuberculosis (TB). METHODS: All adult patients admitted in a department of Internal Medicine over an 8-year period with microbiologically proven MT were retrospectively reviewed. Demographic, medical history, laboratory, imaging, pathologic findings, treatment, and follow-up data were extracted from medical records. RESULTS: Six patients (4 women, 37.6 [21.3-62.1] years) with MT were identified. MT included cardiac mass (n = 1), coronaritis (n = 1), left ventricle spontaneous rupture (n = 1) and myocarditis (n = 3). Pericardial effusion was associated with myocardial involvement in 2 cases. Four patients presented with acute heart failure. CRP serum level was high in all cases. The mean delay between the first symptoms and TB diagnosis was of 6 [1-44] months. The time from admission to diagnosis was of 18 (9-28) days. No patient had human immunodeficiency virus infection. Fluorodeoxyglucose - positron emission tomography (FDG-PET) detected extra-cardiac asymptomatic Mycobacterium tuberculosis infection localization and guided biopsy in 5 cases. As compared to TB patients without cardiac involvement, patients with MT were younger and more frequently women. All patients received antituberculosis therapy for 7.5 to 12 months associated with steroids for at least 6 weeks. Cardiac surgery was required in all but one patient. No patient died over a median follow-up of 1.2 [0.2-4.4] years. CONCLUSION: Our study emphasizes the clinical spectrum of life-threatening MT. Early diagnosis using FDG-PET imaging to target biopsy in extra-cardiac tissues and combined treatment strategy associating antituberculosis therapy, corticosteroids and surgery prevent complications and death.

Diffuse Hypermetabolic Bone Marrow Infiltration in Severe Primary Hyperoxaluria on FDG PET.

A 24-year-old man, with type 1 primary hyperoxaluria (diagnosed at age 20 years after repeated renal lithiasis, due to a I244T mutation frequently encountered in Mediterranean countries) complicated by end-stage renal failure requiring dialysis, was admitted for pancytopenia, refractory to erythropoietin injections. On clinical examination, he presented a hepatosplenomegaly without palpable adenopathy. F-FDG PET/CT revealed intense and diffuse bone marrow uptake in the axial skeleton and preferential long bone metaphyseal uptake. Bone marrow aspiration showed Gaucher-like cells infiltration due to oxalate accumulation in macrophages, leading to the diagnosis of bone marrow involvement by primary hyperoxaluria.

18F-FDG PET/CT in bone sarcoidosis: an observational study.

OBJECTIVE: Bone sarcoidosis is usually rare. Imaging procedures such as fluorine-18 fluorodeoxyglucose positron emission tomography/computed tomography (18F-FDG PET/CT) can reveal bone sarcoidosis with better sensitivity than conventional radiography. We aimed to describe bone sarcoidosis involvement detected with 18F-FDG PET/CT. METHODS: This was an observational retrospective study of individuals with pulmonary sarcoidosis who underwent 18F-FDG PET/CT. According to the ATS/ERS/WASOG criteria, sarcoidosis was diagnosed by the presence of clinical and/or imaging features of sarcoidosis and evidence of non-caseating epithelioid granulomas on a biopsy. We assessed clinical and 18F-FDG PET/CT characteristics. RESULTS: Data for 85 patients with sarcoidosis (56.5% female, median age 47 [range 21-80] years) were analyzed. The median follow-up was 4 years. Among 56 patients, sarcoidosis occurred in more than three organs. According to ATS/ERS/WASOG criteria, bone sarcoidosis was diagnosed in 12 (14%) patients. The spine was the most commonly affected location (92%, n = 11), followed by the pelvis (67%, n = 8), sternum (33%, n = 4), humerus (25%, n = 3), and fingers (17%, n = 2). Only peripheral adenopathy was associated with bone sarcoidosis (p = 0.04). Seven patients had a 18F-FDG PET/CT follow-up, all showing a decrease of bone lesions. CONCLUSION: Bone sarcoidosis occurred in 14% of patients with sarcoidosis, affecting multiple bones and mostly the axial skeleton. 18F-FDG PET/CT seems a sensitive tool for diagnosis and follow-up of bone sarcoidosis.

Nuclear Imaging in Sarcoidosis.

Sarcoidosis is a multisystem granulomatosis which may result in a wide variety of clinical and biological presentations. Symptoms are often nonspecific, and incidental abnormal findings on chest radiography is rather common. Although sarcoidosis resolves favorably in most cases, some localizations can provoke functional impairment or even impact on patients' prognosis. The diagnosis is based on a pathological hallmark which is the non-necrotizing epithelioid-cell rich granuloma. Owing to the ability to detect inflammation throughout the body with a high sensibility, FDG-PET/CT gained a central role in sarcoidosis because it can suggest the diagnosis in certain clinical context, guide biopsy, evaluate the extent of the disease, help assess the prognosis, and monitor immunosuppressive therapy. This review will briefly describe clinical and typical findings of conventional imaging according to organ involvement, in order to highlight the additional information provided by nuclear imaging. In the future, we can expect to further improve diagnostic performance of imaging in some indications through the availability of more specific radiopharmaceuticals and the wider use of combined PET/MRI.

18F-FDG-PET/CT Imaging to Diagnose Septic Emboli and Mycotic Aneurysms in Patients with Endocarditis and Cardiac Device Infections.

PURPOSE OF REVIEW: This review analyzes recent studies evaluating the diagnostic value of 18F-FDG-PET/CT for the detection of peripheral emboli and secondary infectious foci in patients with infective endocarditis and cardiac device infections. RECENT FINDINGS: Detection of extracardiac septic localizations in patients with infective endocarditis and cardiac device infections is crucial, as it may impact the diagnosis, prognosis, and therapeutic management. Recent literature substantiated the clinical usefulness of 18F-FDG-PET/CT in this setting. 18F-FDG-PET/CT has proven its high diagnostic value for the detection of peripheral emboli in patients with infective endocarditis and cardiac device infections, substantially affecting patients' outcome and treatment. A multimodal approach, combining the high sensitivity of 18F-FDG-PET/CT with morphological imaging seems promising.

Uterine intravascular lymphoma as a cause of fever of unknown origin.

Primary intravascular large B cell lymphoma (IVL) remains a diagnostic challenge because of non-specific clinical, laboratory and imaging findings. The aim of the study was to analyse the major characteristics of IVL with uterine involvement. We retrospectively collected features of IVL with uterine involvement that was proven histologically or demonstrated by significant 18FDG uptake on 18FDG-PET/CT. Findings were compared to a comprehensive literature review. Five patients were identified. All of them were admitted for fever of unknown origin (FUO), with haemophagocytic lymphohistiocytosis in three cases. None had gynaecological symptom, contrasting with the literature data. Structural imaging (including whole-body CT scan and pelvic RMI) failed to yield any diagnosis. 18FDG-PET/CT showed intense uterine uptake in all cases. Endometrial biopsy was performed in three cases and was positive in one. Diagnosis was obtained from coelioscopic iliac adenopathy biopsy in one case and from total hysterectomy in another. Punch biopsy of skin lesions led to diagnosis in the two remaining cases. Bone marrow biopsy was normal in all cases. Clinicians should be aware of potential isolated uterine involvement in IVL, especially in elderly women with FUO. Normal structural imaging does not rule out the diagnosis and 18FDG-TEP/CT should be performed to guide high-yielding biopsy.

Characterization of 18F-Fluorodeoxyglucose Uptake Pattern in Noninfected Prosthetic Heart Valves.

BACKGROUND: 18F-Fluorodeoxyglucose (FDG) positron emission tomography/computed tomography (PET/CT) has been recently acknowledged as a diagnostic tool for prosthetic valve endocarditis, but its specificity is limited by uptake on noninfected valves. The objective of this study was to outline the main features of FDG uptake on PET/CT in patients with noninfected prosthetic heart valve (PHV). METHODS AND RESULTS: Our institution's PET/CT database was reviewed to identify patients with PHV, excluding those suspected of infection or who had received antibiotic treatment. PET indication, valve location, and type (biological/mechanical) and time from implantation were collected for each patient. Images with and without attenuation correction were considered for interpretation. The pattern of FDG uptake (absent, homogeneous, or heterogeneous) was recorded. Fifty-four PHVs (51 patients) were identified, including 32 biological valves. Indications for PET were oncology (n=26), suspicion of prosthetic valve endocarditis subsequently excluded (n=17), and history of vasculitis (n=11). A periprosthetic FDG uptake was present in 47 (87%) and 30 (56%) PHVs with and without attenuation correction, respectively, and the pattern was homogeneous in all but 4 (7%) and 3 (6%) PHVs, respectively. On quantitative analysis, maximum standardized uptake values was greater in mechanical than in biological valves (4.0 [2.4-8.0] versus 3.3 [2.1-6.1]; P=0.01) and in patients with vasculitis than in those referred for other indications. The uptake intensity did not differ before and 3 months after valve replacement. CONCLUSIONS: Noninfected PHVs frequently display homogeneous FDG uptake, which remains steady over time. Caution is, therefore, needed when interpreting FDG PET/CT in suspected prosthetic valve endocarditis, with specific attention to uptake pattern.

Positron emission tomography and computed tomography angiography for the diagnosis of giant cell arteritis: A real-life prospective study.

The use of 18F-fluoro-deoxyglucose positron emission tomography scan (FDG-PET) and computed tomography angiography (CTA) to improve accuracy of diagnosis of giant cell arteritis (GCA) is a very important clinical need. We aimed to compare the diagnostic performance of FDG-PET and CTA in patients with GCA.FDG-PET and CTA were acquired in all consecutive patients suspected for GCA. Results of FDG-PET and CTA were compared with the final diagnosis based on clinical judgment, temporal artery biopsy (TAB) findings, and ACR criteria. Sensitivity, specificity, and positive and negative predictive values (PPV, NPV) were calculated for each method.Twenty-four patients suspected for GCA were included. Fifteen (62.5%) were ultimately diagnosed as having GCA. Among them, all fulfilled ACR criteria and 6 had biopsy-proven GCA. Strong FDG uptake in large vessels was found in 10 patients who all had GCA. Mean maximal standard uptake values (SUVmax) per patient measured at all the arterial territories were of 3.7 (range: 2.8-4.7). FDG uptake was negative in 14 patients including 9 and 5 patients without and with GCA, respectively. Mural thickening suggestive of aortitis or branch vessel arteritis was observed on CTA in 11 patients with and 2 patients without GCA. No mural thickening was observed in 11 patients including 7 patients without and 4 patients with GCA. Overall, sensitivity was 66.7% and 73.3%, specificity was 100% and 84.6%, NPV was 64.3% and 64.6%, and PPV was 100% and 84.6% of FDG-PET and CTA, respectively.Both FDG-PET and CTA have a strong diagnostic yield for the diagnosis of GCA. FDG-PET appeared to have a higher PPV as compared to CTA and may be the preferred noninvasive technique to explore patients with suspected GCA.

Tertiary Lymphoid Organs in Takayasu Arteritis.

OBJECTIVE: The role of B cells in the pathogenesis of Takayasu arteritis (TA) is controversial. We aimed to study the presence of tertiary lymphoid organs (TLOs) in the aortic wall of TA patients. METHODS: Hematoxylin and eosin-stained sections from aorta specimens from patients with TA were screened for TLOs. The presence of B cell aggregates (CD20), follicular dendritic cells (FDCs, CD21), and high endothelial venules (HEVs, PNAd) was investigated by immunohistochemistry. Immune cells from the adventitial layer of one patient were characterized by flow cytometry. Demographic, medical history, laboratory, imaging, treatment, and follow-up data were extracted from medical records. RESULTS: Aorta specimens from Bentall procedures were available from seven patients (5 females, aged 22-57 years) with TA. Surgical treatment was performed at TA diagnosis (n = 4) or at a median of 108 months (84-156) after TA diagnosis. Disease was active at surgery in four patients according to NIH score. B cell aggregates-TLOs containing HEVs were observed in the adventitia of all but one patient. Of note, ectopic follicles containing CD21(+) FDCs were found in all patients (4/4) with increased aortic (18)F-fluoro-deoxyglucose (FDG) uptake before surgery but were absent in all but one patients (2/3) with no FDG uptake. In addition, flow cytometry analysis confirmed the accumulation of memory/germinal center-like B cells in the adventitial layer and showed the presence of antigen-experienced T follicular helper cells. CONCLUSION: Ectopic lymphoid neogenesis displaying functional features can be found in the aortic wall of a subset of patients with active TA. The function of these local B cell clusters on the pathogenesis of TA remains to be elucidated.