04- diarrhea.pdf

Diarrhea Dr. Ibrahim AL-Adham Taken from Handbook of Nonprescription Drugs 1 Diarrhea Diarrhea is a symptom characterized by an abnormal increase in stool frequency, liquidity, or weight. Although the normal frequency of...

Diarrhea Dr. Ibrahim AL-Adham Taken from Handbook of Nonprescription Drugs 1 Diarrhea Diarrhea is a symptom characterized by an abnormal increase in stool frequency, liquidity, or weight. Although the normal frequency of bowel movements varies with each individual, having more than 3 bowel movements per day is considered abnormal. Diarrhea may be: Acute, Persistent, Chronic. 2  Acute diarrhea, defined as symptoms lasting less than 14 days, In persistent diarrhea, symptoms last 14 days to 4 weeks. Chronic diarrhea, by definition, lasts more than 4 weeks. Persistent diarrheal illnesses are often secondary to other chronic medical conditions or treatments and need medical care; 3  Epidemiologic factors that increase the risk for particular infectious diarrheal diseases or their spread include: Attendance or employment at day care centers, Occupation as a food handler or caregiver, Congregate living conditions (e.g., nursing homes, prisons, and multifamily dwellings), Consumption of unsafe foods (e.g., raw or undercooked meat, eggs, and shellfish), Presence of medical conditions, such as acquired immunodeficiency syndrome (aids) or diverticulitis. Acute diarrhea may also be caused by poisoning, medications, intolerance of certain foods, or various nongastrointestinal (GI) acute or chronic illnesses. 4  Viral Gastroenteritis Noroviruses are the most common cause of diarrhea in adults and the second most common cause in children Although the virus is most often transmitted by contaminated water or food, it can also be transmitted from person to person and through contact with contaminated environmental surfaces. Rotavirus is the most common cause of severe gastroenteritis in infants and young children worldwide Rotavirus tends to be a seasonal infection, with peaks of gastroenteritis occurring between November and February. It is spread by the fecaloral route, can cause severe dehydration and electrolyte disturbances, and may result in death. Other, less frequent viral causes of gastroenteritis include adenoviruses, astroviruses, and hepatitis A virus. Norovirus may also cause postinfectious IBS. 5 Common Infectious Diarrheas and Their Treatment Epidemiologic/Etiologic Type Symptoms Treatment Usual Prognosis Factors Onset of 24-48 Vigorous fluid and Infects infants; oralfecal hours; vomiting, Selflimiting, Usually Rotavirus electrolyte spread fever, nausea, acute lasts 5-8 days replacement watery diarrhea Infects all ages; frequently Onset of 24-48 spread person to person by Norovirus hours; suddenonset the Fluid and Selflimiting, Usually vomiting, nausea, Fecaloral route; causes “24 electrolytes lasts 12-60 hours headache, myalgia, hour stomach flu” fever, watery diarrhea 6  Bacterial Gastroenteritis Bacteria cause diarrhea through Elaboration of enterotoxin (e.g., ETEC and Staphylococcus aureus), attachment and production of localized inflammatory changes in the gut (e.g., enteroaggregative E. coli [EAEC], enteropathogenic E. coli, STEC, and Clostridium difficile), Directly invading the mucosal epithelial cells (e.g., Shigella, Salmonella, Yersinia, Campylobacter jejuni, and invasive E. coli). Patients with diarrhea caused by toxin producing pathogens have a watery diarrhea, which primarily involves the small intestine. If the large intestine is the primary site of infection, invasive organisms produce a dysentery like (bloody diarrhea) syndrome characterized by fever, abdominal cramps, tenesmus (straining), and the frequent passage of small volume stools that may contain blood and mucus. 7  Enteric infection, most notably bacterial infection caused by Campylobacter, Shigella, Salmonella, and diarrheagenic E. coli, can cause prolonged bowel dysfunction, including irritable bowel syndrome (IBS), a functional bowel disorder characterized by abdominal pain and discomfort following resolution of the infection. Acute gastroenteritis may also unmask or exacerbate underlying chronic gastrointestinal diseases, such as celiac disease, Crohn’s disease, or ulcerative colitis. 8 Common Infectious Diarrheas and Their Treatment Type Epidemiologic/Etiologic Symptoms Treatment Usual Factors Prognosis Ingestion of contaminated Onset of 24-72 hours; Fluid and electrolytes; Campylobacter food or water; oralfecal Selflimiting, nausea, vomiting, in severe or persistent jejuni spread; usually lasts