Clostridial and Clostridioides Infections

Clostridial organisms are spore-forming, anaerobic, gram-positive bacilli that are found in a wide variety of environments, including soil, vegetation, and the gut of healthy animals. Their ability to produce spores allows them to survive for prolonged periods of time in challenging environments, including after exposure to many common household and hospital disinfectants. Another characteristic of clostridia that cause disease is their ability to produce toxins, and it is these toxins that often cause the hallmark features of clostridial infections. The clostridia with the greatest impact on human health today is Clostridioides (formerly Clostridium) difficile, which is the most common cause of health care-associated infections in the United States and is an associated complication in over 20,000 in-hospital deaths per year. By comparison, the incidence of other Clostridioides (e.g., Clostridium tetani, C. botulinum, and C. perfringens) has decreased due to improvements in hygiene and vaccinations, but diseases caused by those agents require prompt recognition and appropriate therapy to avoid preventable morbidity and mortality. Clostridia of emerging importance include Paeniclostridium (formerly Clostridium) sordellii (which is a cause of rapidly fatal infections in postpartum women, after medical abortions, in injection drug users, and after traumatic injuries), and Clostridium novyi (which is a cause of necrotizing infections in injection drug users).