Recurrence of Clostridium difficile infection in the Western Australian population.

Clostridium difficile, the most common cause of hospital-associated diarrhoea in developed countries, presents major public health challenges. The high clinical and economic burden from C. difficile infection (CDI) relates to the high frequency of recurrent infections caused by either the same or different strains of C. difficile. An interval of 8 weeks after index infection is commonly used to classify recurrent CDI episodes. We assessed strains of C. difficile in a sample of patients with recurrent CDI in Western Australia from October 2011 to July 2017. The performance of different intervals between initial and subsequent episodes of CDI was investigated. Of 4612 patients with CDI, 1471 (32%) were identified with recurrence. PCR ribotyping data were available for initial and recurrent episodes for 551 patients. Relapse (recurrence with same ribotype (RT) as index episode) was found in 350 (64%) patients and reinfection (recurrence with new RT) in 201 (36%) patients. Our analysis indicates that 8- and 20-week intervals failed to adequately distinguish reinfection from relapse. In addition, living in a non-metropolitan area modified the effect of age on the risk of relapse. Where molecular epidemiological data are not available, we suggest that applying an 8-week interval to define recurrent CDI requires more consideration.

Torsade de pointes in a child with acute rheumatic fever.

Ventricular arrhythmias are uncommon in acute rheumatic carditis. We report the case of a child who presented with rheumatic carditis, prolonged corrected QT interval, and torsade de pointes. The episodes of torsade were controlled with beta-blockade and cardiac pacing. The child subsequently died as a result of brain injury; the autopsy revealed classic findings of acute rheumatic carditis.

Radiofrequency ablation of an accessory pathway in a surgically created atrioventricular Fontan anastomosis: case report and review of previous published cases.

Supraventricular tachyarrhythmias following the Fontan procedure can be life-threatening. Though most are commonly due to intraatrial reentry, orthodromic reentrant tachycardia may also be present. Atrioventricular accessory pathways may develop across suture lines following right atrial to right ventricular anastomosis in patients with tricuspid atresia. We report a case of a patient who underwent this type of Fontan who developed orthodromic reentrant tachycardia and heart failure. An electrophysiological study revealed the presence of an atrioventricular accessory pathway traversing the Fontan anastomosis suture line. Successful radiofrequency ablation of the accessory pathway led to control of the tachyarrhythmia and improvement of heart failure.

Noninvasive prediction of pulmonary artery pressure in patients with isolated ventricular septal defect.

Management of patients with isolated ventricular septal defect (VSD) requires information regarding pulmonary artery pressure (PAP). The purpose of this study was to evaluate the individual predictive value of noninvasive methods for assessment of PAP and to determine if any combination of techniques significantly improved their predictive power. We reviewed the clinical history, electrocardiogram, and echocardiogram of 31 patients (age 1.9 +/- 1. 73 years) who underwent catheterization for isolated VSD. Noninvasive data were compared for patients with mean PAP <20 mmHg (group 1) and those with mean PAP > or =20 (group 2) at catheterization. Fourteen (45%) patients were in group 1 and 17 (55%) in group 2. Doppler estimation of VSD gradient, right ventricular hypertrophy by echocardiogram, interventricular septal orientation, and VSD size had predictive value for elevated mean PAP (p < 0.01). All patients (n = 6) with normal findings in all four variables had normal PAP. All patients (n = 12) with at least three of four abnormal findings had elevated PAP. Six patients in group 1 had at least one variable that incorrectly predicted high PAP, whereas 3 patients with normal findings on three of the four variables nevertheless had elevated PAP. No single noninvasive variable accurately predicted PAP in all cases. However, normal findings for all four significant variables did predict normal PAP and suggest that cardiac catheterization is unnecessary in that setting. However, any other combination of normal and abnormal findings for the four significant variables did not reliably predict PAP and such patients may require catheterization to directly measure PAP.