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1.
Brain Behav ; 10(3): e01540, 2020 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-31985135

RESUMO

INTRODUCTION: 18 F-fluorodeoxyglucose (FDG)-PET metabolic patterns of brain differ among autoimmune encephalitis with different neuronal surface antigens. In this case report, we compared the topographical relationship of cerebral glucose metabolism and antigen distribution in the patients with anti-NMDAR and anti-AMPAR encephalitis. Literature review summarized the common features of brain metabolism of autoimmune encephalitis. METHODS: The cerebral glucose metabolism was evaluated by FDG-PET/CT during acute-to-subacute stage of autoimmune encephalitis and after treatment. The stereo and quantitative analysis of cerebral metabolism used standardized z-score and visualized on three-dimensional stereotactic surface projection. To map NMDAR and AMPAR in human brain, we adopted genetic atlases from the Allen Institute and protein atlases from Zilles's receptor densities. RESULTS: The three-dimensional stereotactic surface projection displayed frontal-dominant hypometabolism in a 66-year-old female patient with anti-AMPAR encephalitis and occipital-dominant hypometabolism in a 29-year-old female patient with anti-NMDAR encephalitis. Receptor density maps revealed opposite frontal-occipital gradients of AMPAR and NMDAR, which reflect reduced metabolism in the correspondent encephalitis. FDG-PET hypometabolic areas possibly represent receptor hypofunction with spatial correspondence to receptor distributions of the autoimmune encephalitis. The reversibility of hypometabolism was in line with patients' cognitive improvement. The literature review summarized six features of metabolic anomalies of autoimmune encephalitis: (a) temporal hypermetabolism, (b) frontal hypermetabolism and (c) occipital hypometabolism in anti-NMDAR encephalitis, (d) hypometabolism in association cortices, (e) sparing of unimodal primary motor cortex, and (e) reversibility in recovery. CONCLUSIONS: The distinct cerebral hypometabolic patterns of autoimmune encephalitis were representative for receptor hypofunction and topographical distribution of antigenic receptors. The reversibility of hypometabolism marked the clinical recovery of autoimmune encephalitis and made FDG-PET of brain a valuable diagnostic tool.

2.
EJNMMI Res ; 9(1): 2, 2019 Jan 03.
Artigo em Inglês | MEDLINE | ID: mdl-30607646

RESUMO

BACKGROUND: Prosthetic joint infections may lead to failures of total joint arthroplasty. Radionuclide imaging can play a diagnostic role in identifying such infections, which require two-stage exchange arthroplasty (instead of simple revision surgery performed in non-infected cases). Although 18F-FDG PET/CT has emerged as a novel diagnostic tool in this setting, the clinical usefulness of 68Ga-citrate PET/CT has not been previously investigated. This single-center prospective study was designed to address this issue. METHODS: Between January 2016 and October 2017, we examined 34 patients with clinically proven or suspected prosthetic hip/knee joint infections scheduled to undergo surgery. All patients underwent 68Ga-citrate PET/CT scans and sequential 18F-FDG PET/CT imaging for comparative purposes. Intraoperative findings and the results of microbiological analyses of surgical specimens served as gold standard. The diagnostic results were examined according to (1) image interpretation based on radiotracer uptake patterns and (2) quantitative analysis using volumes of interest (VOIs) to calculate standard uptake values (SUVs) and metabolic volumes (MVs). RESULTS: A total of 26 (76%) patients were diagnosed as having infections. Based on radiotracer uptake pattern criteria, the sensitivity, specificity, and accuracy of 68Ga-citrate PET/CT and 18F-FDG PET/CT were 92%, 88%, and 91% and 100%, 38%, and 85%, respectively. MV was significantly higher in the infected group when 68Ga-citrate PET/CT was used (422.45 vs. 303.65 cm3, p = 0.027), whereas no significant differences were observed on 18F-FDG PET/CT. According to receiver operating characteristic (ROC) curve analysis, a cut-off value of 370.86 for MV resulted in a sensitivity of 61.5% and a specificity of 87.5% (area under curve: 0.75, 95% confidence interval: 0.57-0.88, p = 0.035). CONCLUSIONS: Subject to future confirmation, our data provide preliminary evidence that 68Ga-citrate PET/CT may have a complimentary role to 18F-FDG PET/CT in detecting prosthetic joint infections, being characterized by a higher specificity and the possibility to discriminate between an infectious condition and sterile inflammation. TRIAL REGISTRATION: This prospective study was registered at clinicaltrials.gov (registration number: NCT02855190 ).

3.
Contrast Media Mol Imaging ; 2018: 8945130, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30532664

RESUMO

Purpose: Positron emission tomography/magnetic resonance imaging (PET/MRI) can facilitate the use of noninvasive imaging biomarkers in clinical prostate cancer staging. Although multiparametric MRI is a widely used technique, the clinical value of simultaneous PET imaging remains unclear. This study aimed at investigating this issue. Methods: Between January 2015 and December 2016, 31 high-risk prostate cancer patients underwent 11C-choline PET/MRI for staging purposes. Clinical characteristics and imaging parameters, including the standardized uptake value (SUV) and metabolic volumetric parameters from PET imaging; apparent diffusion coefficient (ADC) values from diffusion-weighted imaging; and volume transfer rate constant (Ktrans), reflux rate constant (Kep), and initial area under curve (iAUC) in 60 seconds from dynamic contrast-enhanced (DCE) MRI were analyzed. Results: 11C-Choline PET imaging parameters were significantly correlated with prostate-specific antigen (PSA) levels, and metabolic volumetric parameters, including metabolic tumor volume (MTV) and uptake volume product (UVP), showed significant correlations with other MRI parameters. In our cohort analysis, the PET/MRI parameters UVP/minimal ADC value (ADCmin) and kurtosis of Kep (Kepkur)/ADCmin were significant predictors for progression-free survival (PFS) (HR = 1.01, 95% CI: 1.00-1.02, p=0.031 and HR = 1.09, 95% CI: 1.02-1.16, p=0.009, respectively) in multivariate Cox regression analysis. High UVP/ADCmin and Kepkur/ADCmin values were significantly associated with shorter PFS. Conclusions: Metabolic volumetric parameters such as MTV and UVP can be routinely used as PET imaging biomarkers to add prognostic value and show better correlations in combination with MR imaging parameters in high-risk prostate cancer patients undergoing 11C-choline PET/MRI.


Assuntos
Imagem Multimodal/métodos , Neoplasias da Próstata/diagnóstico por imagem , Idoso , Idoso de 80 Anos ou mais , Biomarcadores/análise , Radioisótopos de Carbono/química , Colina/química , Humanos , Imagem por Ressonância Magnética/métodos , Masculino , Pessoa de Meia-Idade , Tomografia por Emissão de Pósitrons/métodos , Compostos Radiofarmacêuticos/química , Carga Tumoral
4.
J Microbiol Immunol Infect ; 51(6): 839-846, 2018 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-30190232

RESUMO

BACKGROUND/PURPOSE: Bacteremia portends high rates of morbidity and mortality. Although 18F-fluorodeoxyglucose positron emission tomography and computed tomography (18F-FDG PET/CT) imaging has clinical value in assessing fever of unknown origin, its usefulness in bacteremia has not been entirely elucidated. We therefore designed the current single-center retrospective study to investigate 1) the clinical value of 18F-FDG PET/CT imaging in assessing bacteremia and 2) the association between laboratory data and imaging findings. METHODS: We examined 102 patients with bacteremia who had undergone 18F-FDG PET/CT imaging. The patients' clinical and laboratory data were reviewed and analyzed in relation to 18F-FDG PET/CT findings. Patients showing positive results underwent quantitative measurements of 18F-FDG uptake. RESULTS: Positive 18F-FDG PET/CT findings were identified in 74 (72.5%) patients, and 40 (54.1%) underwent modified treatment or management because of the imaging results (p = 0.003). Positive 18F-FDG PET/CT findings were significantly associated with higher white blood cell (WBC) counts and C-reactive protein (CRP) levels (p = 0.012 and < 0.001, respectively). Notably, CRP levels accurately predicted (area under curve = 0.752; p < 0.001) positive 18F-FDG PET/CT findings (optimal cut-off point: 54.025 mg/L). CONCLUSION: A majority (54.1%, n = 40) of the patients with positive 18F-FDG PET/CT results underwent treatment modifications; they accounted for most cases (87%) of management changes in our cohort. Leukocytosis and increased CRP levels are significantly associated with positive 18F-FDG PET/CT findings in patients with bacteremia. CRP levels >54.025 mg/L were accurate predictors of positive 18F-FDG PET/CT results.


Assuntos
Bacteriemia/sangue , Bacteriemia/diagnóstico por imagem , Proteína C-Reativa/análise , Fluordesoxiglucose F18/análise , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Bacteriemia/terapia , Biomarcadores/análise , Criança , Feminino , Hospitais Universitários , Humanos , Leucocitose/sangue , Masculino , Pessoa de Meia-Idade , Tomografia Computadorizada com Tomografia por Emissão de Pósitrons , Estudos Retrospectivos , Taiwan , Adulto Jovem
5.
Eur J Nucl Med Mol Imaging ; 45(3): 462-470, 2018 03.
Artigo em Inglês | MEDLINE | ID: mdl-28951990

RESUMO

BACKGROUND: Acute complicated pyelonephritis (ACP) is an upper urinary tract infection associated with coexisting urinary tract abnormalities or medical conditions that could predispose to serious outcomes or treatment failures. Although CT and magnetic resonance imaging (MRI) are frequently used in patients with ACP, the clinical value of 18F-fluorodeoxyglucose positron emission tomography and computed tomography (FDG PET/CT) has not been systematically investigated. This single-center retrospective study was designed to evaluate the potential usefulness of FDG PET/CT in patients with ACP. METHODS: Thirty-one adult patients with ACP who underwent FDG PET/CT were examined. FDG PET/CT imaging characteristics, including tracer uptake patterns, kidney volumes, and extrarenal imaging findings, were reviewed in combination with clinical data and conventional imaging results. RESULTS: Of the 31 patients, 19 (61%) showed focal FDG uptake. The remaining 12 study participants showed a diffuse FDG uptake pattern. After volumetric approximation, the affected kidneys were found to be significantly enlarged. Patients who showed a focal uptake pattern had a higher frequency of abscess formation requiring drainage. ACP patients showing diffuse tracer uptake patterns had a more benign clinical course. Seven patients had suspected extrarenal coinfections, and FDG PET/CT successfully confirmed the clinical suspicion in five cases. FDG PET/CT was as sensitive as CT in identifying the six patients (19%) who developed abscesses. Notably, FDG PET/CT findings caused a modification to the initial antibiotic regimen in nine patients (29%). CONCLUSIONS: FDG PET/CT may be clinically useful in the assessment of patients with ACP who have a progressive disease course.


Assuntos
Fluordesoxiglucose F18 , Tomografia Computadorizada com Tomografia por Emissão de Pósitrons , Pielonefrite/diagnóstico por imagem , Doença Aguda , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Pielonefrite/complicações , Estudos Retrospectivos
6.
J Nucl Med ; 56(5): 681-7, 2015 May.
Artigo em Inglês | MEDLINE | ID: mdl-25766894

RESUMO

UNLABELLED: Patients with end-stage renal disease undergoing maintenance hemodialysis (MHD) are highly prone to infections. The potential clinical usefulness of (18)F-FDG PET/CT for the detection of infections of unknown origin in this patient population remains unclear. This study was designed to investigate this issue. METHODS: Between October 2011 and July 2014, a total of 104 adult MHD patients with sepsis underwent (18)F-FDG PET/CT for the detection of unknown infection foci. Follow-up was continued until October 2014. Positive (18)F-FDG PET/CT findings and mortality served as the main outcome measures. RESULTS: Of the 104 study patients, 73 (70.2%) had positive (18)F-FDG PET/CT findings, and a total of 95 major infection foci were identified. Eighteen patients (24.6%) had at least 2 infection foci on (18)F-FDG PET/CT scans. Seven (53.8%) of the 13 patients with primary vascular access-related infections had concurrent metastatic foci. Twenty-eight patients (26.9%) had their treatments modified by (18)F-FDG PET/CT results. Multivariate logistic regression analysis demonstrated that low hemoglobin and high C-reactive protein levels at diagnosis were the independent predictors of positive (18)F-FDG PET/CT results. Twenty-seven patients (26.0%) died during their hospital stay, and 24 of them had positive (18)F-FDG PET/CT findings (P = 0.014). Positive (18)F-FDG PET/CT results were an independent predictor of mortality (hazard ratio, 3.896; 95% confidence interval, 1.039-14.613; P = 0.044). CONCLUSION: Our results suggest that (18)F-FDG PET/CT may be clinically useful for detecting occult infection foci in end-stage renal disease patients undergoing MHD. In this population, positive (18)F-FDG PET/CT findings may lead to a significant change in clinical management and independently predict mortality.


Assuntos
Fluordesoxiglucose F18 , Imagem Multimodal , Tomografia por Emissão de Pósitrons , Diálise Renal , Tomografia Computadorizada por Raios X , Idoso , Feminino , Humanos , Falência Renal Crônica/complicações , Falência Renal Crônica/terapia , Masculino , Pessoa de Meia-Idade
7.
J Neurol Sci ; 345(1-2): 244-7, 2014 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-25086854

RESUMO

We report two unusual cases of suppurative meningomyelitis and ventriculitis which were successfully detected by FDG PET/CT. The extent of disease and response to treatment were well-delineated. Our data suggest that FDG PET/CT may be clinically useful in patients with rare infections of the central nervous system.


Assuntos
Infecções do Sistema Nervoso Central/diagnóstico , Fluordesoxiglucose F18 , Compostos Radiofarmacêuticos , Idoso , Infecções do Sistema Nervoso Central/diagnóstico por imagem , Feminino , Humanos , Tomografia por Emissão de Pósitrons , Tomografia Computadorizada por Raios X
8.
PLoS One ; 8(11): e79766, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-24244559

RESUMO

PURPOSE: Retropharyngeal lymph node (RPLN) metastasis is an uncommon finding in patients with oral cavity squamous carcinoma (OSCC). We sought to investigate the clinical outcomes, clinicopathological characteristics, and the priority of treatment with curative intent in OSCC patients with RPLN involvement. METHODS AND MATERIALS: Between January 2007 and January 2011, we identified 36 patients with primary RPLN metastases (n = 10) or RPLN relapse (n = 26). The follow-up continued until June 2013. Disease-specific survival (DSS), disease-free survival (DFS), and the potential benefits of salvage therapy served as the main outcome measures. RESULTS: The 2-year DSS and DFS rates of untreated patients with RPLN involvement were 20% and 24%, respectively. Level IV/V neck lymph node involvement was an adverse prognostic factor for DSS (P = 0.048) and DFS (P = 0.018). All of the patients presenting with neck lymph node involvement at level IV/V died within 6 months. Among patients who were treated for RPLN relapse, the 2-year DSS and DFS rates from the relapse day were 12.8% and 9.6%, respectively. Concomitant contralateral neck lymph node metastases (N2c) were associated with lower 2-year DSS (P = 0.005) and DFS (P = 0.011) rates. Moreover, five (55%) of the nine patients with recurrent disease in the contralateral RPLN had distant metastases within 6 months. Salvage therapy yielded the maximum survival benefit in patients without N2c disease and ipsilateral RPLN involvement alone (P = 0.005). CONCLUSION: OSCC patients with RPLN involvement have poor outcomes. The risk factor for definitive treatment in OSCC patients with FDG PET/CT defined RPLN disease in primary disease was neck lymph node involvement at level IV/V and N2c and/or contralateral RPLN disease in recurrent disease. Treatment efforts with curative intent should be tailored according to individual risk factors.


Assuntos
Carcinoma de Células Escamosas/diagnóstico , Carcinoma de Células Escamosas/mortalidade , Linfonodos/patologia , Neoplasias Bucais/diagnóstico , Neoplasias Bucais/mortalidade , Tomografia por Emissão de Pósitrons , Tomografia Computadorizada por Raios X , Adulto , Idoso , Carcinoma de Células Escamosas/terapia , Feminino , Fluordesoxiglucose F18 , Humanos , Metástase Linfática , Masculino , Pessoa de Meia-Idade , Neoplasias Bucais/terapia , Estadiamento de Neoplasias , Avaliação de Resultados da Assistência ao Paciente , Faringe , Recidiva , Estudos Retrospectivos , Fatores de Risco
9.
PLoS One ; 8(6): e66132, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-23776621

RESUMO

PURPOSE: The role of FDG PET in the evaluation of patients with sepsis of unknown origin remains unclear. We sought to assess the value of FDG PET/CT in patients with sepsis of unknown cause and to define its priority in this group of subjects. METHODS: A total of 53 patients with sepsis of unknown origin underwent FDG PET/CT within two weeks of diagnosis. All of the patients were followed up for at least 3 months after discharge to determine the clinical outcomes. The impact of FDG PET/CT was assessed according to the number of cases who had their treatment modified on the basis of the imaging results. Logistic regression analysis was used to identify the independent predictors of positive FDG PET/CT findings. RESULTS: Of the 53 study patients, 35 (66%) had positive FDG PET/CT findings, and 13 (25%) had their treatment modified on the basis of the imaging results. Logistic regression analysis identified normal serum aspartate aminotransferase (odds ratio [OR]  = 6.134; 95% confidence interval [CI]  = 1.443-26.076, P = 0.014) and increased serum alkaline phosphatase levels (OR = 5.813; 95% CI = 1.386-24.376, P = 0.016) at diagnosis as independent predictors of positive FDG PET/CT findings. A scoring system using these two covariates was developed, which defined three distinct priority groups for FDG PET/CT imaging. CONCLUSION: Our findings suggest that FDG PET/CT may be clinically useful for the detection of occult foci of infection in patients with sepsis of unknown origin.


Assuntos
Fluordesoxiglucose F18 , Tomografia por Emissão de Pósitrons/métodos , Sepse/diagnóstico , Tomografia Computadorizada por Raios X/métodos , Adulto , Idoso , Idoso de 80 Anos ou mais , Feminino , Humanos , Modelos Logísticos , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Sepse/diagnóstico por imagem
10.
Ren Fail ; 32(10): 1177-82, 2010.
Artigo em Inglês | MEDLINE | ID: mdl-20954978

RESUMO

INTRODUCTION: Although the incidence of septic pericarditis in hemodialysis populations is less frequent in the modern antibiotic era, it is still a cause of death partly because diagnosis is sometimes difficult and uncertain. METHODS: From 2002 to 2006, 12 out of a total of 12,213 maintenance hemodialysis patients were referred for management of septic pericarditis. Patients were diagnosed as either definite or probable septic pericarditis. A definite diagnosis of septic pericarditis is based on the discovery of pathogenic bacteria in pericardial effusion, whereas a probable diagnosis is based on the proof of bacterial infection elsewhere in a patient with otherwise unexplained pericarditis, or appropriate response to a trial of systemic antibiotics. RESULTS: Four (33.3%) patients were diagnosed as definite pericarditis, whereas eight (66.7%) patients as probable pericarditis. It was found that although oxacillin-resistant Staphylococcus aureus (ORSA) (4/12 or 33.3%) and tuberculous (4/12 or 33.3%) pericarditis were common, salmonella pericarditis (2/12 or 16.7%) was also not uncommon. Pericardiocentesis, or pericardial window with pericardiectomy, was performed in three (25%) and two (16%) of patients with cardiac tamponade, respectively. Two patients died because of severe ORSA (1/12 or 8%) and salmonella (1/12 or 8%) sepsis. Finally, there were four (33%) patients who developed constrictive pericarditis after follow-up. CONCLUSIONS: These data are important because the spectrum of septic pericarditis was clearly different between Taiwan and other developed countries. Furthermore, it is the only report in which patients were diagnosed as either definite or probable septic pericarditis, therefore improving the sensitivity of diagnosis as in the case of tuberculous pericarditis.


Assuntos
Pericardite/diagnóstico , Sepse/diagnóstico , Idoso , Idoso de 80 Anos ou mais , Feminino , Humanos , Falência Renal Crônica/epidemiologia , Masculino , Pessoa de Meia-Idade , Derrame Pericárdico/diagnóstico por imagem , Pericardiocentese , Pericardite/epidemiologia , Pericardite/microbiologia , Pericardite/cirurgia , Diálise Renal , Sepse/epidemiologia , Tomografia Computadorizada por Raios X
11.
Kidney Blood Press Res ; 32(1): 17-23, 2009.
Artigo em Inglês | MEDLINE | ID: mdl-19212121

RESUMO

INTRODUCTION: This observational study investigated the course and outcome of dialysis pericarditis in diabetic dialysis patients, as previous reports found that in contrast to uremic pericarditis, which responds in most cases to intensive hemodialysis, dialysis pericarditis resolves with intensification of hemodialysis in fewer cases. METHODS: From 2002 through 2006, 88 maintenance hemodialysis patients (47 diabetic and 41 non-diabetic) were referred for management of dialysis pericarditis. RESULTS: Dialysis pericarditis in 85.1% of diabetic and 82.9% of non-diabetic patients improved following institution of intensive hemodialysis. For the few unresponsive and critical cases, 8.5% of diabetic and 7.3% of non-diabetic patients received pericardiocentesis, whereas 6.4% of diabetic and 9.8% of non-diabetic patients received surgical drainage. In terms of outcome, 85.1, 4.3 and 10.6% of diabetic patients were alive without recurrence, alive with recurrence and deceased, respectively. There was no significant difference with their non-diabetic counterparts, for which the percentages were 87.8, 4.9 and 7.3%, respectively (p > 0.05). Kaplan-Meier analysis did not find any significant difference in survival as well (p > 0.05). CONCLUSION: Whether used in diabetics or not, intensive hemodialysis remains the primary and most effective dialysis pericarditis treatment, whereas pericardiocentesis or surgical drainage should be reserved for the few unresponsive and critical cases.


Assuntos
Diabetes Mellitus/terapia , Pericardite/etiologia , Diálise Renal/efeitos adversos , Idoso , Complicações do Diabetes , Progressão da Doença , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Recidiva , Taxa de Sobrevida , Resultado do Tratamento
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