Clostridium perfringens type A and C are the primary etiological agents associated with necrotic enteritis (NE) in poultry. The predisposing factors implicated in the incidence of NE changes the physical properties of the gut, immunological status of birds, and disrupt the gut microbial homeostasis, causing an over-proliferation of C. perfringens. The principal virulence factors contributing to the pathogenesis of NE are the α-toxin, β-toxin, and NetB toxin. The immune response to NE in poultry is mediated by the Th1 pathway or cytotoxic T-lymphocytes. C. perfringens type A and C are also pathogenic in humans, and hence are of public health significance. C. perfringens intoxications are the third most common bacterial foodborne disease after Salmonella and Campylobacter. The restrictions on the use of antibiotics led to an increased incidence of NE in poultry. Hence, it is essential to develop alternative strategies to keep the prevalence of NE under check. The control strategies rely principally on the positive modulation of host immune response, nutritional manipulation, and pathogen reduction. Current knowledge on the etiology, pathogenesis, predisposing factors, immune response, effect on the gut microbial homeostasis, and preventative strategies of NE in this post-antibiotic era is addressed in this review.

The aim of this paper is to review current knowledge on the relationship between presumptive infectious agents and neonatal porcine diarrhoea (NPD). The literature provides information on the rationale for this causation, including the first mention, main understandings gained with respect to, e.g., pathogenesis, and the knowledge to date on the specific relationships. Further, surveys on the presence and relative importance of these pathogens in NPD are included and the methodology used to identify the causation are discussed.

Clostridium bacteremia is a well-known cause of infection in patients with gastrointestinal lesions. However, the clinical characteristics of this infection in cancer patients are unclear. We retrospectively reviewed cases of blood cultures positive for Clostridium species between March 1, 2004 and May 30, 2018 at the Shizuoka Cancer Center Hospital. Medical records of 40 patients who met the study criteria were reviewed for age, gender, underlying disease, history of disease, blood culture results, laboratory test results, and radiographic data. The common sources of Clostridium species in these patients were hepatobiliary tract infection and liver abscess (13/40; 32.5%) and bacteremia/enteritis due to gastrointestinal tumor (13/40; 32.5%). All patients had malignancies, with the most common being colorectal cancer (n = 9) followed by pancreatic cancer (n = 8) and gastric cancer (n = 6). The most common species isolated was C. perfringens followed by C. ramnosum. Twenty-five patients (62.5%) had polymicrobial bacteremia with the following organisms isolated from concurrent blood cultures: Escherichia coli (n = 8) and Klebsiella spp. (n = 7). Of these bacteremia cases, 37 had digestive organ lesions such as gastrointestinal malignancy, peritoneal dissemination, or intestinal infiltration. Seventeen patients died, resulting in an overall mortality rate of 42.5% at 30 days. Common cases of Clostridium bacteremia were derived from gastrointestinal lesions, and because Clostridium bacteremia is observed regardless of species, it should be considered necessary to examine gastrointestinal lesions.