The Role of 18F-Fluorodeoxyglucose Positron Emission Tomography/Computed Tomography in the Diagnosis of Left-sided Endocarditis: Native vs Prosthetic Valves Endocarditis.

BACKGROUND: 18F-fluorodeoxyglucose positron emission tomography/computed tomography (18F-FDG-PET/CT) has emerged as a useful diagnostic tool for suspected infective endocarditis (IE) in patients with prosthetic valves or implantable devices. However, there is limited evidence regarding use of 18F-FDG-PET/CT for the diagnosis of native valve endocarditis (NVE). METHODS: Between 2014 and 2017, 303 episodes of left-sided suspected IE (188 prosthetic valves/ascending aortic prosthesis and 115 native valves) were studied. 18F-FDG-PET/CT accuracy was determined in the subgroups of patients with NVE and prosthetic valve endocarditis (PVE)/ascending aortic prosthesis infection (AAPI). Associations between inflammatory infiltrate patterns and 18F-FDG-PET/CT uptake were investigated in an exploratory ad hoc histological analysis. RESULTS: Among 188 patients with PVE/AAPI, the sensitivity, specificity, and positive and negative predictive values of 18F-FDG-PET/CT focal uptake were 93%, 90%, 89%, and 94%, respectively, while among 115 patients with NVE, the corresponding values were 22%, 100%, 100%, and 66%. The inclusion of abnormal 18F-FDG cardiac uptake as a major criterion at admission enabled a recategorization of 76% (47/62) of PVE/AAPI cases initially classified as "possible" to "definite" IE. In the histopathological analysis, a predominance of polymorphonuclear cell inflammatory infiltrate and a reduced extent of fibrosis were observed in the PVE group only. CONCLUSIONS: Use of 18F-FDG-PET/CT at the initial presentation of patients with suspected PVE increases the diagnostic capability of the modified Duke criteria. In patients who present with suspected NVE, the use of 18F-FDG-PET/CT is less accurate and could only be considered a complementary diagnostic tool for a specific population of patients with NVE.

PET/Computed Tomography Evaluation of Infection of the Heart.

The 2015 European Society of Cardiology guidelines for the management of infective endocarditis included 18F-fluorodeoxyglucose (18F-FDG) PET/computed tomography (CT) in the diagnostic work-up of prosthetic valve endocarditis. This article examines the literature from the last 3 years to highlight the additional role 18F-FDG-PET/CT can contribute to an accurate diagnosis of cardiac infections and associated infectious complications. The challenges and pitfalls associated with 18F-FDG-PET/CT in such clinical settings must be recognized and these are discussed along with the suggested protocols that may be incorporated in an attempt to address these issues.

Reactivation of mucosal and cutaneous leishmaniasis in a renal transplanted patient.

Mucosal leishmaniasis (ML) is a chronic form of tegumentary leishmaniasis, which causes destructive lesions of nasal, pharyngeal, and laryngeal mucosa. We describe a case of leishmaniasis reactivation with simultaneous cutaneous and mucosal forms in a renal transplanted patient with no history of prior leishmaniasis. Reactivation after renal transplantation was not reported in Brazil. A 67-year-old woman receiving prednisone 20 mg/day, tacrolimus 1 mg/day, and mycophenolic acid 360 mg/day presented with nose edema with erythema and cutaneous lesions. Amastigotes were identified on biopsies and the polymerase chain reaction confirmed Leishmania (Viannia) braziliensis. The patient was treated with liposomal amphotericin B but died 3 weeks after as a result of bacterial septic shock. In conclusion, tegumentary leishmaniasis can reactivate with simultaneous cutaneous and mucosal forms in a renal transplanted patient during the immunosuppressant therapy.

Facial structure alterations and abnormalities of the paranasal sinuses on multidetector computed tomography scans of patients with treated mucosal leishmaniasis.

BACKGROUND/OBJECTIVES: Mucosal leishmaniasis (ML) is a progressive disease that affects cartilage and bone structures of the nose and other upper respiratory tract structures. Complications associated with ML have been described, but there is a lack of studies that evaluate the structural changes of the nose and paranasal sinuses in ML using radiological methods. In this study, we aimed to assess the opacification of the paranasal sinuses in patients with treated ML and any anatomical changes in the face associated with ML using multidetector computed tomography scans (MDCT) of the sinuses. We compared the findings with a control group. METHODOLOGY/PRINCIPAL FINDINGS: We evaluated 54 patients with treated ML who underwent CT scans of the sinuses and compared them with a control group of 40 patients who underwent orbital CT scans. The degree of sinus disease was assessed according to the Lund-Mackay criteria. Forty of the 54 patients with a history of ML (74.1%) had a tomographic score compatible with chronic sinusitis (Lund-Mackay ≥4). CT scans in the leishmaniasis and control groups demonstrated significant differences in terms of facial structure alterations. Patients from the ML group showed more severe levels of partial opacification and pansinus mucosal thickening (42.6%) and a greater severity of total opacification. Patients from the ML group with a Lund-Mackay score ≥4 presented longer durations of disease before treatment and more severe presentations of the disease at diagnosis. CONCLUSION/SIGNIFICANCE: CT scans of the sinuses of patients with ML presented several structural alterations, revealing a prominent destructive feature of the disease. The higher prevalence in this study of chronic rhinosinusitis observed in CT scans of patients with treated ML than in those of the control group suggests that ML can be considered a risk factor for chronic rhinosinusitis in this population (p<0.05).