Which clinical condition is caused by Shigella species?

Shigella species are primarily known for causing bacterial dysentery, also referred to as shigellosis. This condition is characterized by diarrhea, which often contains blood and mucus, abdominal pain, fever, and tenesmus (a feeling of incomplete defecation). The bacteria invade the epithelial cells of the intestinal mucosa, leading to inflammation and ulceration of the intestinal lining, which is responsible for the symptoms of dysentery.

Understanding that Shigella is specifically associated with this severe form of diarrhea is crucial in differentiating it from other bacterial infections and conditions. For instance, typhoid fever is caused by Salmonella enterica serotype Typhi, not Shigella, while hemorrhagic colitis is typically associated with Escherichia coli, particularly the strain O157:H7. Urinary tract infections can arise from a variety of bacteria, such as Escherichia coli and Enterococcus, and are not linked to Shigella. Thus, the association of Shigella with bacterial dysentery is significant in clinical microbiology and public health.