Nausea/vomiting with or without diarrhea, with or without cramps.
Often you are what you eat. You can eat a bug or a preformed toxin, the it makes you vomit like Vesuvius or crap like, well, is there a volcano that starts with c? I like alliteration.
Bacillary Causes: Aeromonas, Bacillus, E. coli, Campylobacter, Klebsiella oxytoca, Listeria monocytogenes (your lab will not be looking for it), Plesiomonas, Salmonella, S. aureus (it may well cause disease, esp MRSA), Shigella, Vibrio, Yersinia.
Mostly supportive. Depends on which of the above organisms you are concerned about. Most will get better on their own and do not need treatment. For bacillary diarrhea, usually a quinolone OR rifaximin except for Campylobacter jejuni. Treatment of Escherichia coli may make HUS more likely BUT treatment of E. coli associated travelers diarrhea may lead to less irritable bowel syndrome.
People blame the most recent meal, but with the exception of staphylococcal and bacillus toxins, to get nausea and vomiting takes more than 6 hours.
ICD9 Codes (Soon to be supplanted by ICD10)
Gastroenteritis 558.9; salmonella 003.0; viral NEC 008.8 specified type NEC 008.69.