اسهال

Diarrheal diseases represent one of the five leading causes of death worldwide. The following definitions have been suggested according to the duration of diarrhea: Acute — ≤14 days in duration Persistent diarrhea — more than 14 days in duration Chronic — more than 30 days in duration Most cases of acute diarrhea are due to infections with viruses and bacteria and are self-limited. Noninfectious etiologies become more common as the course of the diarrhea persists and becomes chronic. The major causes of acute infectious diarrhea include viruses, bacteria, and, less often, protozoa. Bacterial causes are responsible for most cases of severe diarrhea. The patient's history can be useful in identifying the pathogens associated with an episode of acute diarrhea and may help to guide empiric therapy. A diagnostically important finding is fever, which suggests infection with invasive bacteria (eg, Salmonella, Shigella, or Campylobacter), enteric viruses, or a cytotoxic organism such as Clostridium difficile or Entamoeba histolytica. A food history may also provide clues to a diagnosis. Symptoms that begin within six hours suggest ingestion of a preformed toxin of Staphylococcus aureus or Bacillus cereus Symptoms that begin at 8 to 16 hours suggest infection with Clostridium perfringens Symptoms that begin at more than 16 hours can result from viral or bacterial infection (eg, contamination of food with enterotoxigenic or enterohemorrhagic E.coli). Syndromes that may begin with diarrhea but progress to fever and more systemic complaints such as head ache, muscle aches, stiff neck may suggest infection with Listeria monocytogenes, particularly in pregnant woman. It is also important to ask about recent antibiotic use (as a clue to the presence of C. difficile infection, although it is possible for community-associated C. difficile infection to occur in patients without antibiotic exposure), other medications, and to obtain a complete past medical history (eg, to identify an immunocompromised host or the possibility of nosocomial infection). Travelers' diarrhea Travelers' diarrhea is the most common illness in persons traveling from resource-rich to resource-poor regions of the world. The fear of developing diarrhea Episodes of travelers' diarrhea (TD) are nearly always benign and self-limited, but the dehydration that can complicate an episode may be severe and pose a greater health hazard than the illness itself. TD is frequently categorized into three forms: classic, moderate, and mild. Classic-passage of three or more unformed stools in a 24 hour period plus at least one of these other symptoms: nausea, vomiting, abdominal pain or cramps, fever, blood in stools Moderate-passage of one or two unformed stools in 24 hours plus at least one of the above symptoms or more than two unformed stools in 24 hours without other symptoms Mild-passage of one or two unformed stools in 24 hours without other symptoms TD should also be in the differential diagnosis when diarrhea develops within 10 days after the individual returns home.   Diarrheal diseases represent one of the five leading causes of death worldwide. The following definitions have been suggested according to the duration of diarrhea: Acute — ≤14 days in duration Persistent diarrhea — more than 14 days in duration Chronic — more than 30 days in duration Most cases of acute diarrhea are due to infections with viruses and bacteria and are self-limited. Noninfectious etiologies become more common as the course of the diarrhea persists and becomes chronic. The major causes of acute infectious diarrhea include viruses, bacteria, and, less often, protozoa. Bacterial causes are responsible for most cases of severe diarrhea. The patient's history can be useful in identifying the pathogens associated with an episode of acute diarrhea and may help to guide empiric therapy. A diagnostically important finding is fever, which suggests infection with invasive bacteria (eg, Salmonella, Shigella, or Campylobacter), enteric viruses, or a cytotoxic organism such as Clostridium difficile or Entamoeba histolytica. A food history may also provide clues to a diagnosis. Symptoms that begin within six hours suggest ingestion of a preformed toxin of Staphylococcus aureus or Bacillus cereus Symptoms that begin at 8 to 16 hours suggest infection with Clostridium perfringens Symptoms that begin at more than 16 hours can result from viral or bacterial infection (eg, contamination of food with enterotoxigenic or enterohemorrhagic E.coli). Syndromes that may begin with diarrhea but progress to fever and more systemic complaints such as head ache, muscle aches, stiff neck may suggest infection with Listeria monocytogenes, particularly in pregnant woman. It is also important to ask about recent antibiotic use (as a clue to the presence of C. difficile infection, although it is possible for community-associated C. difficile infection to occur in patients without antibiotic exposure), other medications, and to obtain a complete past medical history (eg, to identify an immunocompromised host or the possibility of nosocomial infection). Travelers' diarrhea Travelers' diarrhea is the most common illness in persons traveling from resource-rich to resource-poor regions of the world. The fear of developing diarrhea Episodes of travelers' diarrhea (TD) are nearly always benign and self-limited, but the dehydration that can complicate an episode may be severe and pose a greater health hazard than the illness itself. TD is frequently categorized into three forms: classic, moderate, and mild. Classic-passage of three or more unformed stools in a 24 hour period plus at least one of these other symptoms: nausea, vomiting, abdominal pain or cramps, fever, blood in stools Moderate-passage of one or two unformed stools in 24 hours plus at least one of the above symptoms or more than two unformed stools in 24 hours without other symptoms Mild-passage of one or two unformed stools in 24 hours without other symptoms TD should also be in the differential diagnosis when diarrhea develops within 10 days after the individual returns home.