Bacterial pneumonia is an increasing complication of HIV infection and inversely correlates with the CD4+ lymphocyte count. Interleukin (IL)-17 is a cytokine produced principally by CD4+ T cells, which induces granulopoiesis via granulocyte colony-stimulating factor (G-CSF) production and induces CXC chemokines. We hypothesized that IL-17 receptor (IL-17R) signaling is critical for G-CSF and CXC chemokine production and lung host defenses. To test this, we used a model of Klebsiella pneumoniae lung infection in mice genetically deficient in IL-17R or in mice overexpressing a soluble IL-17R. IL-17R–deficient mice were exquisitely sensitive to intranasal K. pneumoniae with 100% mortality after 48 h compared with only 40% mortality in controls. IL-17R knockout (KO) mice displayed a significant delay in neutrophil recruitment into the alveolar space, and had greater dissemination of K. pneumoniae compared with control mice. This defect was associated with a significant reduction in steady-state levels of G-CSF and macrophage inflammatory protein (MIP)-2 mRNA and protein in the lung in response to the K. pneumoniae challenge in IL-17R KO mice. Thus, IL-17R signaling is critical for optimal production of G-CSF and MIP-2 and local control of pulmonary K. pneumoniae infection. These data support impaired IL-17R signaling as a potential mechanism by which deficiency of CD4 lymphocytes predisposes to bacterial pneumonia.

Youth adherence to highly active anti-retroviral therapy (HAART) is poor, and little research exists that identifies the reasons youth have difficulty adhering to medications. Given that complete adherence is necessary for favourable health outcomes, it is essential to examine the obstacles youth face in adhering to HAART. The present investigation sought to identify these barriers and to systematically examine the experiences and attitudes youth have towards medications. Twenty-five adolescents and young adults presenting to a public primary care facility for treatment of HIV infection were asked to participate in focus groups which explored their attitudes and experiences around medication adherence. Participants provided richly detailed descriptions of the challenges of managing HIV stigma and their efforts to hide their status from friends, family, doctors, and even themselves. Fifty percent of respondents indicated that they skipped doses because they feared family or friends would discover their status. These results suggest that HIV stigma impacts treatment for youth on several levels, from the accuracy of communication with medical providers to medication adherence, subsequent health outcomes, and the emergence of treatment resistant strains.

Background Adults with congenital heart disease (CHD) have been considered potentially high risk for novel coronavirus disease-19 (COVID-19) mortality or other complications. Objectives This study sought to define the impact of COVID-19 in adults with CHD and to identify risk factors associated with adverse outcomes. Methods Adults (age 18 years or older) with CHD and with confirmed or clinically suspected COVID-19 were included from CHD centers worldwide. Data collection included anatomic diagnosis and subsequent interventions, comorbidities, medications, echocardiographic findings, presenting symptoms, course of illness, and outcomes. Predictors of death or severe infection were determined. Results From 58 adult CHD centers, the study included 1,044 infected patients (age: 35.1 ± 13.0 years; range 18 to 86 years; 51% women), 87% of whom had laboratory-confirmed coronavirus infection. The cohort included 118 (11%) patients with single ventricle and/or Fontan physiology, 87 (8%) patients with cyanosis, and 73 (7%) patients with pulmonary hypertension. There were 24 COVID-related deaths (case/fatality: 2.3%; 95% confidence interval: 1.4% to 3.2%). Factors associated with death included male sex, diabetes, cyanosis, pulmonary hypertension, renal insufficiency, and previous hospital admission for heart failure. Worse physiological stage was associated with mortality (p = 0.001), whereas anatomic complexity or defect group were not. Conclusions COVID-19 mortality in adults with CHD is commensurate with the general population. The most vulnerable patients are those with worse physiological stage, such as cyanosis and pulmonary hypertension, whereas anatomic complexity does not appear to predict infection severity.

Fontan failure has been variably and inconsistently described in the literature, leading to challenges in comparing studies and evaluating treatments. Development of a conceptual framework to describe clinical phenotypes will aid in consistent terminology in the literature. In the heart failure literature, several key concepts have been described-"heart failure" is a clinical syndrome of various etiologies, with phenotype-specific response to therapies. As the congenital heart disease community struggles to grapple with "Fontan failure," these concepts come to light. Fontan failure in the context of four clinical phenotypes, including evaluation, potential management strategies, and future directions is discussed.