Clostridium difficile. A review on an emerging infection.

Clostridium difficile causes antibiotic-associated diarrhoea and pseudomembranous colitis. The main virulence factors of C. difficile are the toxins A (TcdA) and B (TcdB). A third toxin, binary toxin (CDT), which pathogenetic role had been remained largely overlooked until few years ago, nowadays have been detected in 5%-23% of strains. C. difficile has spread around world. Clostridium difficile infection (CDI) is one of the most common health-care associated infections and a significant cause of morbidity and mortality among older adult hospitalized patients. Diagnosis of CDI is often difficult and has a substantial impact on the management of patients with disease. It is usually based on a clinical history of recent antimicrobial usage and diarrhoea in combination with laboratory tests. Although the conventional methods are crucial for the diagnosis and the subsequent treatment of CDI, a timely laboratory diagnosis is essential for the detection of toxigenic strains providing either to an effective and immediately treatment or to the prevention of further disease transmission. In this review we provide general recommendations for testing of samples collected from patients with suspected CDI.

Ischemic cardiomyopathy: lack of clinical applicability of the WHO/ISFC classification of cardiomyopathies.

BACKGROUND: The classification of cardiomyopathies proposed by the WHO/ISFC Task Force defines ischemic cardiomyopathy as "a dilated cardiomyopathy with impaired contractile performance not explained by the extent of coronary disease or ischemic damage". The aim of this study was to verify the clinical applicability of the WHO/ISFC definition of ischemic cardiomyopathy. METHODS: Retrospective analysis of the clinical characteristics of patients with a left ventricular ejection fraction < 40%, in whom coronary angiography showed a) stenosis < or = 50% of a main coronary artery and/or b) stenosis > 50% of a distal portion of a main coronary artery or of a secondary branch. The patients with a clinical diagnosis of previous myocardial infarction were excluded. RESULTS: Fourteen patients with the angiographic characteristics listed above were identified. Twelve patients were males, mean age 59 years. They represented 3.8% of all the patients with left systolic ventricular dysfunction who underwent coronary angiography in the same period. The left ventricular end-diastolic volume was 170 +/- 45 ml/m2 and the ejection fraction was 27 +/- 6%. The cause of systolic left ventricular dysfunction was systemic arterial hypertension in 3 patients, diabetes mellitus in 2, a combination of these diseases in 4, chronic alcohol abuse in 1, a previous clinically silent myocardial infarction in 1, and idiopathic dilated cardiomyopathy in 3. CONCLUSIONS: In conclusion, in all our patients with severe left ventricular dysfunction which was not explained by the extent of coronary artery disease, at least one possible cause of impaired contractile performance could be identified. Thus the definition of ischemic cardiomyopathy according to the new WHO/ISFC classification of cardiomyopathies appears to be of scarce utility on clinical grounds and should be redefined and if necessary reclassified.