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Medical Author:

Charles Patrick Davis, MD, PhD

Charles Patrick Davis, MD, PhD

Dr. Charles "Pat" Davis, MD, PhD, is a board certified Emergency Medicine doctor who currently practices as a consultant and staff member for hospitals. He has a PhD in Microbiology (UT at Austin), and the MD (Univ. Texas Medical Branch, Galveston). He is a Clinical Professor (retired) in the Division of Emergency Medicine, UT Health Science Center at San Antonio, and has been the Chief of Emergency Medicine at UT Medical Branch and at UTHSCSA with over 250 publications.

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Medical Editor:

Melissa Conrad Stöppler, MD, Chief Medical Editor

Melissa Conrad Stöppler, MD, Chief Medical Editor

Melissa Conrad Stöppler, MD, is a U.S. board-certified Anatomic Pathologist with subspecialty training in the fields of Experimental and Molecular Pathology. Dr. Stöppler's educational background includes a BA with Highest Distinction from the University of Virginia and an MD from the University of North Carolina. She completed residency training in Anatomic Pathology at Georgetown University followed by subspecialty fellowship training in molecular diagnostics and experimental pathology.

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The majority of Salmonella spp are ingested with food or water although direct contact with animals has increased as a source of the organisms to cause infection. In people with normal gastrointestinal tracts and immune systems, researchers have estimated that about 1 million to 1 billion S. spp need to be ingested to cause infection, because normal human stomach acid can kill large numbers of these bacteria. If some bacteria reach the intestine, the organisms can attach to intestinal cells where S. spp toxins (cytotoxin and enterotoxin) can damage and kill cells. The intestinal cell damage results in the inability of the body to normally retain and adsorb fluids, so diarrhea results. In some people, the diarrhea can cause serious dehydration. However, the majority of S. spp-caused infections are then eventually eliminated by the person's immune defenses. Some S. spp are not eliminated; these bacteria survive the initial immune response by living inside cells (macrophages) of the immune system. The bacteria can sometimes spread to the blood (bacteremia). Some S. spp (for example, S. typhi) can also enter the gallbladder and remain there. The patient can recover from the disease but still sheds bacteria through the gallbladder secretions (bile) into the feces. This person thus becomes a carrier of S. spp and potentially can infect many others, especially if the person lives in unsanitary conditions or works in the food-processing industry.

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Abdominal Pain in Children Abdominal pain in children can range from trivial to life-threatening. Some possible causes of abdominal pain in children are: infections, food related (food al...learn more >>

Dehydration in Adults Dehydration occurs when the loss of body fluids (mostly water), exceeds the amount that is taken in. Causes of dehydration include fever, vomiting, diarrhea, di...learn more >>

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