Takayasu arteritis with recurrent coronary artery disease.

Takayasu arteritis is a rare type of large vessel vasculitis that commonly affects individuals of Asian descent. Coronary artery involvement is rare. We report the case of a young female with history of Takayasu arteritis who underwent stenting and reported with in-stent restenosis. She was managed with robot-assisted coronary artery bypass grafting using bilateral internal mammary arteries.

Neuroinvasive Bacillus cereus Infection in Immunocompromised Hosts: Epidemiologic Investigation of 5 Patients With Acute Myeloid Leukemia.

Background: Bacillus cereus is a ubiquitous gram-positive rod-shaped bacterium that can cause sepsis and neuroinvasive disease in patients with acute leukemia or neutropenia. Methods: A single-center retrospective review was conducted to evaluate patients with acute leukemia, positive blood or cerebrospinal fluid test results for B cereus, and abnormal neuroradiographic findings between January 2018 and October 2022. Infection control practices were observed, environmental samples obtained, a dietary case-control study completed, and whole genome sequencing performed on environmental and clinical Bacillus isolates. Results: Five patients with B cereus neuroinvasive disease were identified. All patients had acute myeloid leukemia (AML), were receiving induction chemotherapy, and were neutropenic. Neurologic involvement included subarachnoid or intraparenchymal hemorrhage or brain abscess. All patients were treated with ciprofloxacin and survived with limited or no neurologic sequelae. B cereus was identified in 7 of 61 environmental samples and 1 of 19 dietary protein samples-these were unrelated to clinical isolates via sequencing. No point source was identified. Ciprofloxacin was added to the empiric antimicrobial regimen for patients with AML and prolonged or recurrent neutropenic fevers; no new cases were identified in the ensuing year. Conclusions: B cereus is ubiquitous in the hospital environment, at times leading to clusters with unrelated isolates. Fastidious infection control practices addressing a range of possible exposures are warranted, but their efficacy is unknown and they may not be sufficient to prevent all infections. Thus, including B cereus coverage in empiric regimens for patients with AML and persistent neutropenic fever may limit the morbidity of this pathogen.

Evaluating the Diagnostic Efficacy of 99mTc-Methionine Single-Photon Emission Computed Tomography-Computed Tomography: A Head-to-Head Comparison with 11C-Methionine Positron Emission Tomography-Magnetic Resonance Imaging in Glioma Patients.

Background: Amino acid positron emission tomography (PET) imaging plays a significant role in the diagnosis of gliomas and in differentiating tumor recurrence from necrosis. In this study, the authors evaluated the diagnostic efficacy of [99mTc]Tc-methionine single-photon emission computed tomography-computed tomography (SPECT-CT) in comparison with [11C]methionine PET-magnetic resonance imaging (MRI) in delineating tumors. Methods: Thirty-one (primary: 16 and postoperative: 15) patients of confirmed (either MRI or histopathological proven) glioma underwent both [99mTc]Tc-methionine SPECT-CT and [11C]methionine PET-MRI. A comparative analysis was performed between SPECT, PET, and MR images to calculate the concordance between the modalities and to evaluate the diagnostic efficacy of the [99mTc]Tc-methionine SPECT. Results: [99mTc]Tc-methionine SPECT showed comparable uptake in the tumor lesions in comparison to [11C]methionine PET. A significant and strong positive correlation was observed between the volume of tumor (Vt) in PET and Vt MR (p < 0.004). Likewise, a significant and strong positive correlation was found between Vt SPECT and Vt MR. [99mTc]-methionine has a sensitivity and specificity of 91% and 75%, respectively, compared with 82% and 100% for [11C]methionine in postoperative cases to differentiate the tumor recurrence from necrosis. The sensitivity and specificity of [99mTc]Tc-methionine was 92% and 100%, respectively, compared with 92% and 67% for [11C]methionine in primary tumors. Conclusion: [99mTc]Tc-methionine SPECT-CT is as equally good as [11C]methionine for diagnosing and differentiating it from necrosis especially in high-grade glioma.

Total arterial revascularization using robot assisted minimally invasive coronary artery bypass: an Indian experience.

Objective: The aim of this study is to analyze the early outcomes of Total Arterial Revascularization using Robot Assisted Minimally Invasive Coronary Artery Bypass at our center between June 2019 and January 2023. Methods: This is a retrospective analysis of 195 patients who underwent Total Arterial Coronary Revascularization through Robot Assisted Minimally Invasive Coronary Artery Bypass procedure (RA-CABG) during the period of June 2019 and January 2023 in a quaternary care center in India. Primary outcome variables were in-hospital and 30-day mortality. Secondary outcome variables included duration of surgery, length of intensive care unit (ICU) stay, in-hospital stay and perioperative morbidity. The entire patient population was divided into two groups for a subgroup analysis based on when the surgery was conducted i.e. the years since the robotic program was begun at our institution with 81 patients in group I (2019-2021), and 114 patients in group II (2022-2023). Results: 195 patients [88.7% male, mean age of 61.34 ± 9.58 years] underwent RA-CABG during the 5-year period (2019-2023) by a single experienced surgeon and his team. Conversion to larger thoracic incisions was required in 5 cases (2.59%). In-hospital and 30-day mortality was 1.02% each. The average length of ICU stay and hospital stay were 2.82 ± 1.17 days and 5.84 ± 1.71 days respectively. The duration of ICU stay correlated with the number of internal mammary artery grafts procured (p = 0.0022). Median duration of follow-up was 11 months. Overall mortality was 3.62% and cardiac related mortality was 2.07%, and 5 patients (2.59%) underwent percutaneous coronary intervention. Results of the sub-group analysis revealed a statistically significant difference between the groups in terms of number of internal mammary artery grafts procured (p = 0.010), need for transfusions (p = 0.00031), ICU stay (p = 0.0005) and in-hospital stay (p = 0.0006). Conclusions: Total Arterial Coronary Revascularization through RA-CABG is a viable procedure in select patients. An experienced surgeon and team are required. Further studies in the form of randomized trials with long term follow-up are required to establish the overall utility, effectiveness and benefits to the patients.

Development of an economical method to synthesize O-(2-[18 F]fluoroethyl)-L-tyrosine (18 FFET).

Positron emission tomography (PET) using O-(2-[18 F]fluoroethyl)-L-tyrosine ([18 F]FET) has shown great success in differentiating tumor recurrence from necrosis. In this study, we are reporting the experience of synthesis [18 F]FET by varying the concentration of TET precursor in different chemistry modules. TET precursor (2-10 mg) was used for the synthesis of [18 F]FET in an automated (MX Tracerlab) module (n = 6) and semiautomated (FX2N Tracerlab) module (n = 19). The quality control was performed for all the preparations. For human imaging, 220 ± 50 MBq of [18 F]FET was briefly injected into the patient to acquire PET-MR images. The radiochemical purity was greater than 95% for the final product in both modules. The decay corrected average yield was 10.7 ± 4.7% (10 mg, n = 3) and 8.2 ± 2.6% (2 mg, n = 3) with automated chemistry module and 36.7 ± 7.3% (8-10 mg, n = 12), 26.4 ± 3.1% (5-7 mg, n = 4), and 35.1 ± 3.8% (2-4 mg, n = 3) with semiautomated chemistry modules. The PET imaging showed uptake at the lesion site (SUVmax = 7.5 ± 2.6) and concordance with the MR image. The [18 F]FET was produced with a higher radiochemical yield with 2.0 mg of the precursor with substantial yield and is suitable for brain tumor imaging.

Synthesis, characterization, and radiosynthesis of fluorine-18-AVT-011 as a Pgp chemoresistance imaging marker.

P-glycoprotein (Pgp) is the most studied ATP-binding cassette (ABC) efflux transporter and contributes to chemoresistance. A few tracers have been developed to detect the in-vivo status of chemoresistance using positron emission tomography (PET) imaging. In our study, we have synthesized labeled AVT-011 with fluorine-18 (18F) followed by in-vitro and in-vivo analysis. Tosylate AVT-011 precursor was synthesized and characterized by 1H-NMR and 13C-NMR. AVT-011 was labeled with 18F using the nucleophilic substitution method, and a standard set of quality control was performed. The specificity for Pgp was tested in U87MG cells with and without an inhibitor (tariquidar). The biodistribution and in-vivo stability were tested in the small animals (mice). The biodistribution data of [18F]-AVT-011 was extracted from the PET-CT imaging of breast cancer patients (n = 6). The precursor was synthesized with 36 ± 4% yield and 97 ± 2% purity. The labeling was more than 95% with a 42 ± 2% yield, as evaluated by Radio-HPLC. The cell-binding assay showed a specificity of the tracer for Pgp as the uptake increased by twice after blocking the Pgp receptors. The radiotracer showed a hepatorenal excretion pathway for clearance in an animal study. The uptake was higher in the liver, lungs, spleen, and heart at 15 min and decreased at 60 min. The patients' distribution showed similar uptake patterns as observed in the small animals. [18F]AVT-011 was characterized successfully with high radiochemical purity and yield. The in-vitro and in-vivo studies proved its specificity for Pgp and safe for patient use.