It derives from a need to treat people whose brain function has been impaired as a result of disease, brain damage, toxins, or drugs. In medicine, conceptual distinctions are considered useful to the degree that they can help to guide treatments. The medical approach focuses mostly on the amount of consciousness a person has: in medicine, consciousness is assessed as a "level" ranging from coma and brain death at the low end, to full alertness and purposeful responsiveness at the high end.Consciousness is of concern to patients and physicians, especially neurologists and anesthesiologists. Patients may have disorders of consciousness or may need to be anesthetized for a surgical procedure. Physicians may perform consciousness-related interventions such as instructing the patient to sleep, administering general anesthesia, or inducing medical coma. Also, bioethicists may be concerned with the ethical implications of consciousness in medical cases of patients such as the Karen Ann Quinlan case, while neuroscientists may study patients with impaired consciousness in hopes of gaining information about how the brain works. Assessment
In medicine, consciousness is examined using a set of procedures known as neuropsychological assessment. There are two commonly used methods for assessing the level of consciousness of a patient: a simple procedure that requires minimal training, and a more complex procedure that requires substantial expertise. The simple procedure begins by asking whether the patient is able to move and react to physical stimuli. If so, the next question is whether the patient can respond in a meaningful way to questions and commands.
Bacillary dysentery is a type of dysentery, and is a severe form of shigellosis. Bacillary dysentery is associated with species of bacteria from the family Enterobacteriaceae. The term is usually restricted to Shigella infections.Shigellosis is caused by one of several types of Shigella bacteria. Three species are associated with bacillary dysentery: Shigella sonnei, Shigella flexneri and Shigella dysenteriae. A study in China indicated that Shigella flexneri 2a  was the most common serotype.Salmonellosis caused by Salmonella enterica (serovar Typhimurium) has also been described as a cause of bacillary dysentery, though this definition is less common. It is sometimes listed as an explicit differential diagnosis of bacillary dysentery, as opposed to a cause.Bacillary dysentery should not be confused with diarrhea caused by other bacterial infections. One characteristic of bacillary dysentery is blood in stool, which is the result of invasion of the mucosa by the pathogen. History
The Bacteria causing Shigellosis is named after "Shiga" a Japanese researcher who discovered the bacteria in 1897

Pathogenesis
Transmission is fecal-oral and is remarkable for the small number of organisms that may cause disease (10 ingested organisms cause illness in 10% of volunteers, and 500 organisms cause disease in 50% of volunteers). Shigella bacteria invade the intestinal mucosal cells but do not usually go beyond the lamina propria. Dysentery is caused when the bacteria escape the epithelial cell phagolysosome, multiply within the cytoplasm, and destroy host cells. Shiga toxin causes hemorrhagic colitis and hemolytic-uremic syndrome by damaging endothelial cells in the microvasculature of the colon and the glomeruli, respectively.