No abstract

Haemophilus influenzae is a Gram-negative pathobiont, frequently recovered from the airways of persons with cystic fibrosis (pwCF). Previous studies of H. influenzae infection dynamics and transmission in CF predominantly used molecular methods, lacking resolution. In this retrospective cohort study, representative yearly H. influenzae isolates from all pwCF attending the Calgary Adult CF Clinic with H. influenzae positive sputum cultures between 2002 and 2016 were typed by pulsed-field gel electrophoresis. Isolates with shared pulsotypes common to ≥ 2 pwCF were sequenced by Illumina MiSeq. Phylogenetic and pangenomic analyses were used to assess genetic relatedness within shared pulsotypes, and epidemiological investigations were performed to assess potential for healthcare associated transmission. H. influenzae infection was observed to be common (33% of patients followed) and dynamic in pwCF. Most infected pwCF exhibited serial infections with new pulsotypes (75% of pwCF with ≥ 2 positive cultures), with up to four distinct pulsotypes identified from individual patients. Prolonged infection by a single pulsotype was only rarely observed. Intra-patient genetic diversity was observed at the single-nucleotide polymorphism and gene content levels. Seven shared pulsotypes encompassing 39% of pwCF with H. influenzae infection were identified, but there was no evidence, within our sampling scheme, of direct patient-to-patient infection transmission.

CaseAn 80-year-old woman presented to the emergency department of a community hospital with a 4-day history of intermittent retrosternal chest discomfort. She had no history of cardiovascular disease. Her cardiac risk factors included age, dyslipidemia, and a remote smoking history. A 12-lead electrocardiogram showed inferoposterior ST elevation. She was administered acetylsalicylic acid, clopidogrel bisulfate (Plavix, Bristol-Myers Squibb, New York, NY), enoxaparin, and metoprolol, and transferred to a university centre for urgent coronary angiography.Angiography (Fig. 1) showed severe, extensive ectasia with complete occlusion of the right coronary artery with a large clot, approximately 17 mm in diameter, and diffuse disease in the left coronary artery.Given the significant ectasia and the late presentation, a conservative approach was taken. She was managed medically without complication and discharged 5 days later. The decision to not perform angioplasty on the right coronary artery was based on the Occluded Artery Trial (OAT) study, 1 which showed no benefit of angioplasty of a total occlusion in asymptomatic patients whose myocardial infarction was more than 72 hours old. The left anterior descending stenosis was not opened up, because we are waiting on the results of the COMPLETE study for guidance in this matter.Coronary artery ectasia (CAE) is commonly defined as dilatation of a coronary artery to 1.5 times greater than that of an adjacent normal segment. 2 It is present in 1% to 3% of patients with obstructive coronary artery disease at autopsy or