Surveillance cultures following a regional outbreak of carbapenem-resistant .

Objectives: The primary aim of this study was to assess the epidemiology of carbapenem-resistant Acinetobacter baumannii (CRAB) for 9 months following a regional outbreak with this organism. We also aimed to determine the differential positivity rate from different body sites and characterize the longitudinal changes of surveillance test results among CRAB patients.

Design: Observational study.

Patient-to-Patient Transmission of Klebsiella pneumoniae Carbapenemase Variants with Reduced Ceftazidime-Avibactam Susceptibility.

We report patient-to-patient transmission of isolates with reduced susceptibility to ceftazidime-avibactam due to production of KPC-40, a variant of KPC-3 with a two-amino-acid insertion in the Ω-loop region (L167_E168dup). The index patient had received a prolonged course of ceftazidime-avibactam therapy, whereas the second patient had not received the agent and still became colonized with the KPC-40-producing strain. The complex dynamics of KPC ( carbapenemase) described here highlight several key diagnostic and therapeutic considerations.

Use of a cohorting-unit and systematic surveillance cultures to control a Klebsiella pneumoniae carbapenemase (KPC)-producing Enterobacteriaceae outbreak.

Objective: Describe the epidemiological and molecular characteristics of an outbreak of Klebsiella pneumoniae carbapenemase (KPC)-producing organisms and the novel use of a cohorting unit for its control.

Design: Observational study.

Setting: A 566-room academic teaching facility in Milwaukee, Wisconsin.

Human IL12RB1 expression is allele-biased and produces a novel IL12 response regulator.

Human IL12RB1 is an autosomal gene that is essential for mycobacterial disease resistance and T cell differentiation. Using primary human tissue and PBMCs, we demonstrate that lung and T cell IL12RB1 expression is allele-biased, and the extent to which cells express one IL12RB1 allele is unaffected by activation. Furthermore following its expression the IL12RB1 pre-mRNA is processed into either IL12RB1 Isoform 1 (IL12Rβ1, a positive regulator of IL12 responsiveness) or IL12RB1 Isoform 2 (a protein of heretofore unknown function).

Dietary Vitamin D3 Suppresses Pulmonary Immunopathology Associated with Late-Stage Tuberculosis in C3HeB/FeJ Mice.

Tuberculosis (TB) is a significant human disease caused by inhalation of Mycobacterium tuberculosis. Left untreated, TB mortality is associated with a failure to resolve pulmonary immunopathology. There is currently widespread interest in using vitamin D3 (VitD3) as an adjunct therapy for TB because numerous in vitro studies have shown that VitD3 has direct and indirect mycobactericidal activities.

IL12B expression is sustained by a heterogenous population of myeloid lineages during tuberculosis.

IL12B is required for resistance to Mycobacterium tuberculosis (Mtb) infection, promoting the initiation and maintenance of Mtb-specific effector responses. While this makes the IL12-pathway an attractive target for experimental tuberculosis (TB) therapies, data regarding what lineages express IL12B after infection is established are limited. This is not obvious in the lung, an organ in which both hematopoietic and non-hematopoietic lineages produce IL12p40 upon pathogen encounter.

Inflammatory signals direct expression of human IL12RB1 into multiple distinct isoforms.

IL12RB1 is essential for human resistance to multiple intracellular pathogens, including Mycobacterium tuberculosis. In its absence, the proinflammatory effects of the extracellular cytokines IL-12 and IL-23 fail to occur, and intracellular bacterial growth goes unchecked. Given the recent observation that mouse leukocytes express more than one isoform from il12rb1, we examined whether primary human leukocytes similarly express more than one isoform from IL12RB1.