Algorithm(s)
PDF algorithm(s) available at www.arupconsult.com.
Diarrhea, Acute Testing AlgorithmClinical Background
Campylobacter species
Epidemiology
- Incidence - Campylobacter jejuni is leading cause of bacterial gastroenteritis in the U.S.
- Age - affects all age groups with peak incidence among children under 5 years of age
- Occurrence
- Campylobacter-caused diarrheal cases are sporadic, but most occur in the spring and fall
- Associated with incorrect food handling practices, consumption of poorly cooked poultry, raw milk, contact with pets and travel
- Outbreaks commonly associated with raw milk and contaminated water
- Campylobacter-caused diarrheal cases are sporadic, but most occur in the spring and fall
Organism
- Campylobacter spp are motile, gram-negative curved or spiral-shaped rods with fastidious growth requirements
Clinical Presentation
- Campylobacter gastroenteritis ranges from asymptomatic infection to severe, inflammatory diarrhea
- Onset of symptoms occurs 2-5 days after ingestion of contaminated food or water
- Symptoms
- Abdominal pain
- Watery stools containing blood and mucous
- Fever
- Nausea or vomiting
- Symptoms generally last 7-10 days
- Complications include reactive arthritis (increased risk if individual is positive for HLA-B27 phenotype), Guillain-Barré syndrome and hemolytic syndrome
- Complications in patients with AIDS or hypogammaglobulinemia include relapse and osteomyelitis (especially with HLA-B27 phenotype)
Treatment
- Antimicrobial-based in conjunction with supportive care
Salmonella species
Epidemiology
- Incidence
- 70% of U.S. cases are related to international travel
- Remaining 30% of cases are from large, sporadic outbreaks
- Transmission
- Non-symptomatic individuals can transmit disease to others
- Incubation period is 3-21 days
- Remaining 30% of cases are from large, sporadic outbreaks
Organism
- Salmonella are motile gram-negative bacilli belonging to the family Enterobacteriaceae
- Subgroup 1 pathogenic for humans
- Etiologic agent of typhoid fever
Clinical Presentation
- Typhoid fever
- Prodrome of chills, headache, sore throat, fever, anorexia, cough
- Progresses with rash (rose spots), epistaxis, diarrhea, relative bradycardia
- 90% have positive blood cultures in week 1, drops to 50% by week 3
- Late complications found in untreated adults and include intestinal perforation and gastrointestinal hemorrhage
- Rare complications include pancreatitis, hepatic and splenic abscesses, endocarditis, pericarditis, orchitis, meningitis, parotitis, osteomyelitis
- Up to half of infected individuals develop chronic carrier state
- Usually occurs in patients with gall bladder disease or gastric carcinomas
- Fatality rate is 10%
- Enteritis
- Onset of symptoms 6-48 hours after exposure; typically with resolution after 1-2 days
- Fever, headache
- Intestinal symptoms - diarrhea (watery), abdominal pain
- Associated foods include raw meat, poultry, eggs, milk, salad dressing, shrimp and peanut butter
- Onset of symptoms 6-48 hours after exposure; typically with resolution after 1-2 days
Treatment
- Antimicrobial therapy in conjunction with supportive care
Escherichia species (Shiga toxin)
Epidemiology
- Incidence - in the very young and elderly, renal failure (HUS), thrombocytopenia and encephalopathy may occur
- Age - most common in the very young and elderly
- Transmission
- Person-to-person contact is a source of outbreaks in daycare facilities and nursing homes
- Outbreaks from consumption of undercooked meats and unwashed produce
Organism
- E. coli is a gram-negative bacillus belonging to the family Enterobacteriaceae
- Shiga toxin-producing strains (eg, E. coli 0157:H7) cause hemorrhagic colitis and hemolytic uremic syndrome (HUS)
Clinical Presentation
- Watery diarrhea turning to bloody diarrhea
- Abdominal pain
- Symptoms usually resolve within 8 days
Treatment
- Supportive; antibiotics do not improve outcomes and may increase the risk of developing HUS
- Treatment efficacy not well established since disease is usually self-limiting
Shigella species
Epidemiology
- Incidence - prevalent worldwide distribution
- Common in countries where sanitation is poor
- Accounts for <10% of reported outbreaks of foodborne illness in the U.S.
- Transmission - fecal-oral route
Organism
- Shigella are gram-negative, nonmotile bacilli belonging to the family Enterobacteriaceae
- Agent of bacillary dysentery
- 4 species - S. dysenteriae, S. flexneri, S. boydii, S. sonnei
- Some strains produce enterotoxin and shiga toxin
Clinical Presentation
- Diarrhea, frequently bloody and may contain mucous or pus
- Fever
- Abdominal pain, cramps
- Dysentery (10-30 stools/day)
- Onset of symptoms 12-50 hours after exposure
- Complications include reactive arthritis (increased risk of development if individual is positive for HLA-B27 allele) and HUS (usually S. dysenteriae type 1)
- Associated with Reiter syndrome (arthritis, uveitis, urethritis)
Treatment
- Antimicrobial-based in conjunction with supportive care
Yersinia species
Epidemiology
- Age - most often in young children
- Transmission - through soil, water, animals, food
Organism
- Yersinia spp are gram-negative coccobacillary organisms
- 3 species most commonly isolated from humans - Y. pseudotuberculosis, Y. pestis, Y. enterocolitica
- Y. pseudotuberculosis and Y. pestis are uncommon causes of gastrointestinal disease
- Y. enterocolitica can be found in meats (beef, pork, etc.) oysters, fish and unpasteurized milk
Clinical Presentation
- Onset of symptoms 24-48 hours after ingestion of contaminated food or drink
- Infection manifests in gastrointestinal tract causing symptoms of diarrhea (loose, watery, or bloody stools), abdominal pain and fever
- Infections with Y. enterocolitica and Y. pseudotuberculosis can be asymptomatic, mild, or severe, with infection resolving within a few weeks, with or without use of antibiotics
- Yersinia infections are known for mimicking appendicitis
- Complications include reactive arthritis which can manifest 1 to 4 weeks post-infection (increased risk of development if individual is positive for HLA-B27 allele)
- Occurs in about 2-3% of cases
- The most commonly affected joints are knees and ankles, but other joints such as toes, fingers and wrists can be involved
- In most cases, 2-4 joints become involved sequentially and asymmetrically over a period of a few days to 2 weeks
- In two-thirds of cases, acute arthritis persists for 1-4 months
- Joint fluid is sterile
- Chronic joint disease or ankylosing spondylitis occurs rarely
- Reiter syndrome (arthritis, uveitis and urethritis) occurs in 5%
- Less common nonsuppurative sequelae of Y. enterocolitica infections include reactive uveitis, iritis, conjunctivitis, glomerulonephritis, urethritis, HUS
Treatment
- Antimicrobial-based in conjunction with supportive care
Vibrio species
Epidemiology
- Incidence
- Several pandemics of V. cholerae infection have occurred, but no major outbreaks have been recently reported in the U.S.
- Sporadic cases occur frequently, particularly in the summer months along coastal waters
- Transmission
- Through ingestion of contaminated seafood or through open wounds in marine waters
Organism
- Vibrio are motile gram-negative bacilli
- Species which may cause gastroenteritis with decreasing frequency include V. parahaemolyticus, V. cholerae, V. vulnificus
- Some strains produce enterotoxin and shiga toxin
- V. parahaemolyticus is the leading cause of bacterial diarrhea associated with foods such as seafood, crab, shrimp, lobster
- V. vulnificus is the leading cause of death in the U.S. related to seafood consumption
- Fatalities are typically due to septicemia and are more common in patients with hepatic disease
Clinical Presentation
- Healthy individuals typically have onset of symptoms within 16 hours of ingestion of contaminated seafood
- Watery diarrhea, abdominal pain, cramps, vomiting
- Immunocompromised individuals and patients with cirrhosis may present with “primary septicemia”
- Associated with >50% mortality
- No associated long-term complications
Treatment
- Antimicrobial and supportive
Aeromonas species
Epidemiology
- Incidence
- Causes sporadic cases of gastroenteritis
- No associated known outbreaks
- Most commonly affects children and immunocompromised adults
- Transmission - through ingestion of raw or undercooked seafood and meat
Organism
- Motile gram-negative bacilli
- Found in fresh and brackish waters
- Species associated with enteritis are A. hydrophilia, A. caviae, A.sobria
Clinical Presentation
- Diarrhea varies from watery to mucous with blood, abdominal pain, fever
- Immunocompromised individuals may develop septicemia
Treatment
- Antimicrobial
See Also
