What Are Toxin-Mediated Diseases?

Discussion A poison is a generic term for “a substance with an inherent property that tends to destroy life or impair health.” A toxin is more specific and is “any poison produced by an organism, characterized by antigenicity in certain animals and high molecular weight, and including the bacterial toxins that are the causative agents of tetanus, diphtheria, etc., and such plant and animal toxins as ricin and snake venom.” A toxin does not include those substances that are made synthetically produced. Venom is also a toxin that is used by animals and insects for predation or defense which can cause disease in humans such as snake venom, bee venom, etc. Toxins can be cell associated (i.e. endotoxin) or secreted (i.e. exotoxin). Other terminology describes the action of the toxin such as leukocidin, enterotoxin or neurotoxin. Some toxins enter cells directly or some are receptor-mediated. Exposure to a toxin does not necessarily cause disease as the exposure may not allow penetration into the body, the concentration of the toxin is not high enough, or the body’s defense systems counteract/neutralize the threat. Vaccines can help the immune system prevent some toxin-mediated diseases. Learning Point Common toxin-mediated diseases in humans include: Bacteria Anthrax – Bacillus anthracis, enters body through inhalation, disrupts cellular defense Bacillus fragilis – is part of gut microbiome, enters through gut, can cause sepsis or other ...
Source: PediatricEducation.org - Category: Pediatrics Authors: Tags: Uncategorized Source Type: news