Responsibilities and Interests of Pediatricians Practicing Hospital Medicine in the United States.

BACKGROUND AND OBJECTIVES: In 2016, the American Board of Medical Specialties (ABMS) approved pediatric hospital medicine (PHM) as the newest pediatric subspecialty. To characterize development of the field, this article aims to: (1) describe the responsibilities and practice settings of US pediatricians self-identifying as hospitalists; and (2) determine how exclusive PHM practice, compared with PHM practice in combination with general or subspecialty care, was associated with professional development interests. METHODS: Pediatricians enrolling in the 2017-2018 American Board of Pediatrics (ABP) Maintenance of Certification program were offered a voluntary survey about their responsibilities, interests, and practice settings. Logistic regression was employed to characterize associations between exclusive PHM practice and: (1) interest in quality improvement (QI) leadership; (2) intention to take the PHM certifying exam; (3) satisfaction with allocation of professional time; and (4) intention to maintain more than one ABP certification. RESULTS: The survey response rate was 70.0%; 1662 (13.1%) self-reported PHM practice. Four-hundred ninety-one (29.5%) practiced PHM exclusively, 518 (31.1%) practiced PHM and general pediatrics, and 653 (39.3%) practiced PHM and one or more subspecialties. Respondents reporting exclusive PHM practice were significantly more likely to report interest in QI leadership or consultation (adjusted odds ratio [OR], 1.39; 95% CI, 1.09-1.79), PHM exam certification (adjusted OR, 7.10; 95% CI, 5.45-9.25), and maintenance of more than one ABP certification (adjusted OR, 2.64; 95% CI, 1.89-3.68). CONCLUSIONS: Hospitalists reported diverse clinical and nonclinical responsibilities. Those practicing PHM exclusively expressed high levels of interest in board certification and QI leadership. Ongoing monitoring of PHM responsibilities and practice settings will be important to support the professional development of the PHM workforce.

Polymeric nanoparticle PET/MR imaging allows macrophage detection in atherosclerotic plaques.

RATIONALE: Myeloid cell content in atherosclerotic plaques associates with rupture and thrombosis. Thus, imaging of lesional monocytes and macrophages could serve as a biomarker of disease progression and therapeutic intervention. OBJECTIVE: To noninvasively assess plaque inflammation with dextran nanoparticle (DNP)-facilitated hybrid positron emission tomography/magnetic resonance imaging (PET/MRI). METHODS AND RESULTS: Using clinically approved building blocks, we systematically developed 13-nm polymeric nanoparticles consisting of cross-linked short chain dextrans, which were modified with desferoxamine for zirconium-89 radiolabeling ((89)Zr-DNP) and a near-infrared fluorochrome (VT680) for microscopic and cellular validation. Flow cytometry of cells isolated from excised aortas showed DNP uptake predominantly in monocytes and macrophages (76.7%) and lower signal originating from other leukocytes, such as neutrophils and lymphocytes (11.8% and 0.7%, P<0.05 versus monocytes and macrophages). DNP colocalized with the myeloid cell marker CD11b on immunohistochemistry. PET/MRI revealed high uptake of (89)Zr-DNP in the aortic root of apolipoprotein E knock out (ApoE(-/-)) mice (standard uptake value, ApoE(-/-) mice versus wild-type controls, 1.9±0.28 versus 1.3±0.03; P<0.05), corroborated by ex vivo scintillation counting and autoradiography. Therapeutic silencing of the monocyte-recruiting receptor C-C chemokine receptor type 2 with short-interfering RNA decreased (89)Zr-DNP plaque signal (P<0.05) and inflammatory gene expression (P<0.05). CONCLUSIONS: Hybrid PET/MRI with a 13-nm DNP enables noninvasive assessment of inflammation in experimental atherosclerotic plaques and reports on therapeutic efficacy of anti-inflammatory therapy.