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FOODBORNE ILLNESS-SALMONELLA

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Classification   |    Detailed evidence-based information

Substances Included Synonyms

Therapeutic Toxic Class

    A) Salmonella is a rod-shaped, motile (except for nonmotile S. gallinarum and S. pullorum), non-sporeforming, gram-negative bacterium, which is a facultative intracellular anaerobe. Approximately 2500 serotypes cause human disease, however, several serotypes account for the majority of infections. S. Enteritidis and S. Typhimurium are common in the United States.

Specific Substances

    1) S agona (synonym)
    2) S arizonae (synonym)
    3) S chameleon (synonym)
    4) S diarizonae (synonym)
    5) S enterica (synonym)
    6) S heidelberg (synonym)
    7) S houtenae (synonym)
    8) S indica (synonym)
    9) S java (synonym)
    10) S javiana (synonym)
    11) S marinum (synonym)
    12) S oranienburg (synonym)
    13) S paratyphi B (synonym)
    14) S salamae (synonym)
    15) S typhimurium (synonym)
    16) Salmonella enteritidis (synonym)
    17) Salmonella food poisoning (synonym)
    18) Food poisoning Salmonella (synonym)
    19) Typhoid fever (synonym)

Available Forms Sources

    A) SOURCES
    1) FOODBORNE
    a) Most cases of salmonellosis occur from contamination of food. Eggs and poultry are the most common sources, but pork, beef, fruit, vegetables, and dairy products have also been implicated (Linam & Gerber, 2007).
    b) CHICKEN: Salmonella has contaminated 7.2% of raw broiler chicken samples from poultry processing plant (Centers for Disease Control and Prevention, 2009). Twenty-three cases of Salmonella heidelberg infection, associated with consumption of frozen processed chicken nuggets and/or chicken strips were reported in British Columbia, Canada from January to April, 2003 (MacDougall et al, 2004).
    c) EGG AND MILK PRODUCTS: Salmonellosis may result from consumption of raw milk products and raw or undercooked egg-based products (Haeghebaert et al, 2003). A multi-state outbreak of Salmonella Enteritidis infections was linked to shell eggs (Centers for Disease Control and Prevention (CDC), 2010).
    d) POWDERED INFANT FORMULA: At least 6 outbreaks of Salmonella infection (n=287 cases) have been linked to powdered infant formulas (Cahill et al, 2008).
    e) SESAME SEED PRODUCTS: Salmonella has been detected and identified in various sesame seed products, including sesame paste and halvah (a mixture of sesame seed paste and acidified heated glucose syrup) (Brockmann et al, 2004).
    f) PEANUT BUTTER: A multi-state outbreak of Salmonella typhimurium affecting 529 persons from 43 states was linked to peanut butter and peanut butter-containing products (Centers for Disease Control and Prevention, 2009a).
    g) OTHER: Many additional food sources have been implicated in outbreaks, including contaminated raw alfalfa sprouts, dry dog food, jalapeno peppers, contaminated frozen potpies, and puffed vegetable snacks (Centers for Disease Control and Prevention, 2008; Centers for Disease Control and Prevention, 2008a; Centers for Disease Control and Prevention, 2009; Centers for Disease Control and Prevention (CDC), 2010). Salmonella Arizona was isolated from rattlesnake capsules and sold as a Latino folk remedy (Waterman et al, 1990).
    h) Cross contamination from one food source to another can occur. Handling a contaminated pet and then touching food can spread Salmonella (Center for Food Safety and Applied Nutrition (CFSAN), 2012).
    2) NON-FOODBORNE SOURCES - REPTILE AND AMPHIBIAN VECTORS
    a) Reptiles and amphibians represent an important source of nontyphoidal Salmonella infections. Outbreaks have been associated with exposure to small turtles (Harris et al, 2009), aquatic frogs (Centers for Disease Control and Prevention, 2009), iguanas, snakes, and other reptiles (Mermin et al, 1997; Centers for Disease Control and Prevention, 2003). These outbreaks may simulate foodborne outbreaks.

Overview

Life Support

    A) This overview assumes that basic life support measures have been instituted.

Clinical Effects

    0.2.1) SUMMARY OF EXPOSURE
    A) CAUSATIVE ORGANISM
    1) Salmonella is a rod-shaped, motile (except for nonmotile S. gallinarum and S. pullorum), non-sporeforming, gram-negative bacterium, which is a facultative intracellular anaerobe. Approximately 2500 serotypes cause human disease, however, several serotypes account for the majority of infections. S. Enteritidis and S. Typhimurium are common in the United States.
    B) EPIDEMIOLOGY
    1) NONTYPHOIDAL SALMONELLOSIS: In the United States, an estimated 1.4 million non-typhoidal Salmonella infections occur annually, resulting in 168,000 visits to physicians, 15,000 hospitalizations and 580 deaths. TYPHOID FEVER: In the United States, approximately 1821 cases of typhoid fever occur annually. More cases may occur in people who travel internationally. Approximately 433 cases of typhoid fever are culture-confirmed. Worldwide, millions of cases are reported annually, resulting in thousands of deaths.
    C) TARGET POPULATION
    1) Although people of any age can be affected, the highest incidence and severity occur in elderly and children under 5 years of age, of whom nearly 25% are under 1 year of age. Other factors that increase susceptibility are immunosuppression (eg, AIDS patients), elderly, people on certain medications (eg, chemotherapy, immunosuppressive agents), and chronic disease states.
    D) MECHANISM
    1) NONTYPHOIDAL SALMONELLOSIS: Salmonella organisms penetrate and enter the gut lumen into epithelium of small intestine, leading to inflammation and diarrhea. It has been suggested that enterotoxin may be produced, possibly within enterocytes. TYPHOID FEVER: Salmonella organisms penetrate and enter the gut lumen into epithelium of small intestine, resulting in severe inflammation and diarrhea. It may also enter the bloodstream causing systemic disease (ie, septicemia). It has been suggested that enterotoxin may be produced, possibly within enterocytes.
    E) WITH POISONING/EXPOSURE
    1) ACUTE SYMPTOMS
    a) There are 2 main forms of illness related to Salmonella:
    1) NONTYPHOIDAL SALMONELLOSIS: Most commonly caused by Salmonella enteritidis. Nausea, vomiting, diarrhea, abdominal cramps, weakness, fever, and chills develop within 6 to 72 hours of exposure to contaminated food or water. Stools are loose, slimy, foul-smelling, and may be grossly bloody or green. Diarrhea is usually self-limited, lasting 3 to 7 days. Diarrhea lasting more than 10 days suggests another diagnosis. Septicemia may occur in severe cases.
    2) TYPHOID FEVER: Caused by Salmonella typhi and Salmonella paratyphi. Following an incubation period of 7 to 21 days, diarrhea, abdominal pain, headache, malaise, weakness, and fever develop. This may progress to abdominal distention, constipation, splenomegaly, septicemia, disseminated infection, relative bradycardia, rash, and meningismus. Complications include septicemia, resulting in endocarditis, pericarditis, pneumonitis, orchitis, focal abscess, toxic megacolon, and intestinal perforation. Untreated, the duration of symptoms is typically in the range of 2 to 4 weeks. This is a rare infection in the United States.
    b) The best clinical predictor of a positive stool culture for Salmonella is the combination of diarrhea persisting for more than 24 hours, fever (greater than 37.7 degrees C), and either blood in the stool or abdominal pain with nausea or vomiting.
    2) CHRONIC SYMPTOMS
    a) Postenteritis reactive arthritis (an autoimmune response, not directly from the infection) and Reiter's syndrome may be observed after 3 to 4 weeks after the onset of acute symptoms. Patients with reactive arthritis may have joint inflammation, urethritis, uveitis, and/or conjunctivitis. The gallbladder is the usual seat of infection in the carrier state.
    3) ROUTE OF EXPOSURE
    a) Salmonella is usually spread by fecal-oral route, and is generally associated with contaminated food or water. Salmonella species are most commonly found in contaminated eggs, poultry, and dairy products, but they have been reported in numerous food products (eg, pork, beef, fruit, vegetables) and animal hosts. Reptiles and amphibians represent an important source of nontyphoidal Salmonella infections. Outbreaks have been associated with exposure to small turtles, aquatic frogs, iguanas, snakes, and other reptiles. These outbreaks can be similar to foodborne outbreaks.
    4) TIME TO ONSET
    a) NONTYPHOIDAL SALMONELLOSIS: 6 to 72 hours. TYPHOID FEVER: 1 to 3 weeks, but may be as long as 2 months post-exposure.
    5) DURATION
    a) NONTYPHOIDAL SALMONELLOSIS: usually 4 to 7 days; acute symptoms usually lasts 1 to 2 days or longer. TYPHOID FEVER: 2 to 4 weeks.
    0.2.3) VITAL SIGNS
    A) WITH POISONING/EXPOSURE
    1) Fever has been reported in patients diagnosed with foodborne typhoid fever.

Laboratory Monitoring

    A) Obtain a complete blood count to assess for leukocytosis, leukopenia, or anemia (in the setting of diarrheal blood loss).
    B) Blood cultures are indicated in children less than 1 year of age, immunocompromised patients, or patients who are clinically toxic.
    C) Stool cultures should be obtained to identify serotypes. Genetic identification of about 100 Salmonella serotypes from pure culture is now available. Traditional serotyping can be used to identify the remaining 2400-plus serotypes. Stool cultures should be obtained when a bacterial etiology of gastroenteritis is suspected. Indications include bloody diarrhea, high fever, toxic clinical appearance, prolonged course, immunocompromised host, or for epidemiologic purposes. Stool culture results can take 3 to 7 days. Due to the time involved with stool culture detection, treatment decisions should be based on the patient's presentation.

Treatment Overview

    0.4.2) ORAL/PARENTERAL EXPOSURE
    A) MANAGEMENT OF TOXICITY
    1) Treatment is primarily symptomatic and supportive. Initial assessment determines the magnitude and type of dehydration. Rapid correction of deficits and careful monitoring of intake and output are essential. Patients with mild fluid deficits can often be managed with oral fluid therapy consisting of clear liquids or specially formulated electrolyte solutions. Patients with moderate to severe dehydration are generally treated with IV fluids.
    2) ANTIBIOTIC THERAPY: The use of antibiotics in patients with salmonellosis may increase the risk of the occurrence of bacteremia. Antibiotics are not indicated for diseases limited to the gastrointestinal tract because it may lead to the emergence of resistant organisms. Systemic antibiotic therapy is indicated for diseases caused by Salmonella typhosa, life-threatening diseases outside the gastrointestinal tract, for chronically ill patients, young children, and debilitated adults. Trimethoprim/sulfamethoxazole or quinolones are generally the drugs of choice.
    a) CIPROFLOXACIN: ADULT DOSE: 500 mg orally twice daily for 5 to 7 days (14 days if immunocompromised). Contraindicated if the patient is less than 16 years of age or pregnant.
    b) TRIMETHOPRIM AND SULFAMETHOXAZOLE: ADULT DOSE: 160 mg trimethoprim and 800 mg sulfamethoxazole orally twice daily for 5 to 7 days (14 days if immunocompromised). PEDIATRIC DOSE: 5 mg/kg trimethoprim and 25 mg/kg sulfamethoxazole orally twice daily for 5 to 7 days (14 days if immunocompromised).
    c) CEFTRIAXONE: ADULT DOSE: 100 mg/kg of body weight/day in 1 or 2 divided doses.
    B) DECONTAMINATION
    1) Not indicated.
    C) ANTIDOTE
    1) None.
    D) PATIENT DISPOSITION
    1) HOME CRITERIA: Patients with mild diarrhea may be treated on an outpatient basis if compliance will be adequate; close follow-up care is essential.
    2) ADMISSION CRITERIA: All patients with significant toxicity, severe dehydration, clinical instability, abnormal electrolyte concentrations, or baseline immunocompromised state should be admitted for intravenous rehydration and antibiotic therapy.
    3) OBSERVATION CRITERIA: Patients with severe symptoms should be sent to a healthcare facility for evaluation and treatment.
    E) PITFALLS
    1) Because early symptoms and signs are nonspecific, they may be attributed to other conditions.
    F) TOXICOKINETICS
    1) Incubation period of 12 to 72 hours. One study indicated that greater than 50% of patients stop excreting nontyphi Salmonella within 5 weeks after infection and 90% were culture negative at 9 weeks. Duration of excretion was increased in children under 5 years of age.
    G) DIFFERENTIAL DIAGNOSIS
    1) The differential diagnosis includes other bacterial (eg, E. coli) or nonbacterial (eg, viruses, plants or mushrooms ingestion) causes of acute gastroenteritis; exposure to chemicals (eg, insecticides, pesticides).

Range Of Toxicity

    A) TOXICITY: INFECTIVE DOSE: Nontyphoidal salmonellosis: As low as 1 cell, depending on age and health of the patient and strain differences; typhoid fever: Less than 1000 cells. FATALITY RATE: Nontyphoidal salmonellosis: less than 1%; S. dublin: 15% when septicemic in the elderly; S. enteritidis: 3.6% in hospital/nursing home outbreaks. Typhoid fever: Up to 10% if untreated. Approximately 42% of patients over 50 years of age with confirmed Salmonella gastroenteritis required hospitalization in 2009, with a case-fatality rate of 1.3% in this age group.

Clinical Effects

Summary Of Exposure

    A) CAUSATIVE ORGANISM
    1) Salmonella is a rod-shaped, motile (except for nonmotile S. gallinarum and S. pullorum), non-sporeforming, gram-negative bacterium, which is a facultative intracellular anaerobe. Approximately 2500 serotypes cause human disease, however, several serotypes account for the majority of infections. S. Enteritidis and S. Typhimurium are common in the United States.
    B) EPIDEMIOLOGY
    1) NONTYPHOIDAL SALMONELLOSIS: In the United States, an estimated 1.4 million non-typhoidal Salmonella infections occur annually, resulting in 168,000 visits to physicians, 15,000 hospitalizations and 580 deaths. TYPHOID FEVER: In the United States, approximately 1821 cases of typhoid fever occur annually. More cases may occur in people who travel internationally. Approximately 433 cases of typhoid fever are culture-confirmed. Worldwide, millions of cases are reported annually, resulting in thousands of deaths.
    C) TARGET POPULATION
    1) Although people of any age can be affected, the highest incidence and severity occur in elderly and children under 5 years of age, of whom nearly 25% are under 1 year of age. Other factors that increase susceptibility are immunosuppression (eg, AIDS patients), elderly, people on certain medications (eg, chemotherapy, immunosuppressive agents), and chronic disease states.
    D) MECHANISM
    1) NONTYPHOIDAL SALMONELLOSIS: Salmonella organisms penetrate and enter the gut lumen into epithelium of small intestine, leading to inflammation and diarrhea. It has been suggested that enterotoxin may be produced, possibly within enterocytes. TYPHOID FEVER: Salmonella organisms penetrate and enter the gut lumen into epithelium of small intestine, resulting in severe inflammation and diarrhea. It may also enter the bloodstream causing systemic disease (ie, septicemia). It has been suggested that enterotoxin may be produced, possibly within enterocytes.
    E) WITH POISONING/EXPOSURE
    1) ACUTE SYMPTOMS
    a) There are 2 main forms of illness related to Salmonella:
    1) NONTYPHOIDAL SALMONELLOSIS: Most commonly caused by Salmonella enteritidis. Nausea, vomiting, diarrhea, abdominal cramps, weakness, fever, and chills develop within 6 to 72 hours of exposure to contaminated food or water. Stools are loose, slimy, foul-smelling, and may be grossly bloody or green. Diarrhea is usually self-limited, lasting 3 to 7 days. Diarrhea lasting more than 10 days suggests another diagnosis. Septicemia may occur in severe cases.
    2) TYPHOID FEVER: Caused by Salmonella typhi and Salmonella paratyphi. Following an incubation period of 7 to 21 days, diarrhea, abdominal pain, headache, malaise, weakness, and fever develop. This may progress to abdominal distention, constipation, splenomegaly, septicemia, disseminated infection, relative bradycardia, rash, and meningismus. Complications include septicemia, resulting in endocarditis, pericarditis, pneumonitis, orchitis, focal abscess, toxic megacolon, and intestinal perforation. Untreated, the duration of symptoms is typically in the range of 2 to 4 weeks. This is a rare infection in the United States.
    b) The best clinical predictor of a positive stool culture for Salmonella is the combination of diarrhea persisting for more than 24 hours, fever (greater than 37.7 degrees C), and either blood in the stool or abdominal pain with nausea or vomiting.
    2) CHRONIC SYMPTOMS
    a) Postenteritis reactive arthritis (an autoimmune response, not directly from the infection) and Reiter's syndrome may be observed after 3 to 4 weeks after the onset of acute symptoms. Patients with reactive arthritis may have joint inflammation, urethritis, uveitis, and/or conjunctivitis. The gallbladder is the usual seat of infection in the carrier state.
    3) ROUTE OF EXPOSURE
    a) Salmonella is usually spread by fecal-oral route, and is generally associated with contaminated food or water. Salmonella species are most commonly found in contaminated eggs, poultry, and dairy products, but they have been reported in numerous food products (eg, pork, beef, fruit, vegetables) and animal hosts. Reptiles and amphibians represent an important source of nontyphoidal Salmonella infections. Outbreaks have been associated with exposure to small turtles, aquatic frogs, iguanas, snakes, and other reptiles. These outbreaks can be similar to foodborne outbreaks.
    4) TIME TO ONSET
    a) NONTYPHOIDAL SALMONELLOSIS: 6 to 72 hours. TYPHOID FEVER: 1 to 3 weeks, but may be as long as 2 months post-exposure.
    5) DURATION
    a) NONTYPHOIDAL SALMONELLOSIS: usually 4 to 7 days; acute symptoms usually lasts 1 to 2 days or longer. TYPHOID FEVER: 2 to 4 weeks.

Vital Signs

    3.3.1) SUMMARY
    A) WITH POISONING/EXPOSURE
    1) Fever has been reported in patients diagnosed with foodborne typhoid fever.
    3.3.3) TEMPERATURE
    A) WITH POISONING/EXPOSURE
    1) CASE SERIES: Seven people developed typhoid fever after eating at an Indian buffet restaurant in Japan. Only 1 of the 7 patients had traveled to an endemic country (Nepal) 6 months earlier, but had no symptoms of typhoid fever upon his return. A Nepali chef of the Indian restaurant (index patient 8), who had contact with the salad in the restaurant, was suspected to be the carrier and the source of the outbreak, as he had moved from Nepal to Japan approximately 1.5 years earlier, and had conducted frequent travel between Nepal and Japan. Blood culture samples of all 7 patients were positive for Salmonella enterica Typhi. The mean incubation period was 17.4 days (ranging from 10 to 27 days). Symptoms included fever (n=7, 100%), diarrhea (n=6, 86%), abdominal pain (n=2, 29%), and vomiting (n=2, 29%). All 7 patients recovered with antibiotic therapy. The blood culture sample of the index patient was also positive for S. enterica Typhi and, although he remained asymptomatic, he was also treated with a course of antibiotic therapy (Kobayashi et al, 2016).

Heent

    3.4.3) EYES
    A) WITH POISONING/EXPOSURE
    1) Photophobia has been described (Keogh et al, 1984).

Cardiovascular

    3.5.2) CLINICAL EFFECTS
    A) BRADYCARDIA
    1) WITH POISONING/EXPOSURE
    a) Classically, temperature-pulse dissociation or relative bradycardia in the setting of fever has been described as a hallmark of typhoid fever. This finding was described in 12 of 15 adult patients (Hoffner et al, 2000).
    B) MYOCARDITIS
    1) WITH POISONING/EXPOSURE
    a) Myocarditis, chest pain, pericardial friction rub, sinus tachycardia, and precordial ST-T wave changes were noted in a 17-year-old man with Salmonella typhi infection. Clinical and ECG findings normalized within 96 hours (Keogh et al, 1984).

Respiratory

    3.6.2) CLINICAL EFFECTS
    A) PNEUMONIA
    1) WITH POISONING/EXPOSURE
    a) Salmonella infection may cause pneumonia (Black et al, 1981).

Neurologic

    3.7.2) CLINICAL EFFECTS
    A) MUSCLE WEAKNESS
    1) WITH POISONING/EXPOSURE
    a) Weakness may occur (Baird-Parker, 1990).
    B) MENINGITIS
    1) WITH POISONING/EXPOSURE
    a) Meningitis may occur via bacterial seeding in septicemic patients with intestinal infections caused by Salmonella species (Norris, 1986; Hardy et al, 1984; Black et al, 1981).
    C) HEADACHE
    1) WITH POISONING/EXPOSURE
    a) Headache was reported in 55% of patients (n=20) who developed Salmonella heidelberg infection following consumption of uncooked, frozen, processed chicken nuggets and strips (MacDougall et al, 2004).

Gastrointestinal

    3.8.2) CLINICAL EFFECTS
    A) GASTROENTERITIS
    1) WITH POISONING/EXPOSURE
    a) Gastroenteritis is the most common clinical presentation. Fever, vomiting, and diarrhea (often bloody) usually begin within 6 to 72 hours of exposure and diminish over a 3- to 5-day period. Chills, abdominal cramping, and weight loss are also common (Center for Food Safety and Applied Nutrition (CFSAN), 2012; MacDougall et al, 2004; Cody et al, 1999; Villar et al, 1999).
    1) These symptoms may be absent in older children, who may present instead with abdominal pain and nausea, which may often be confused with acute appendicitis (Fey et al, 2000).
    2) The best clinical predictor of a positive stool culture for Salmonella is the combination of diarrhea persisting for more than 24 hours, fever (greater than 37.7 degrees C), and either blood in the stool or abdominal pain with nausea or vomiting (Koplan et al, 1980).
    3) TOXIC MEGACOLON with colon dilatation reaching a diameter of up to 14 cm has been reported in a 15-year-old girl as a result of Salmonella typhimurium gastroenteritis (Raz et al, 1988).
    4) INTUSSUSCEPTION has been associated with Salmonella typhimurium enterocolitis in an adult (Matsushita et al, 1994).
    5) Salmonella carriage is a common problem, with most patients having positive cultures for 3 to 4 months (Baird-Parker, 1990; Barkin, 1985; Edelman & Levine, 1980; Drachman, 1974).
    b) TYPHOID FEVER: Salmonella Typhi and Salmonella paratyphi infection causes fever and a severe prolonged disease. The incubation period is 7 to 21 days (Center for Food Safety and Applied Nutrition (CFSAN), 2012).
    1) Clinically, patients develop gastroenteritis followed by the onset of fever, malaise, headache, and myalgia. Constipation may occur. Hepatosplenomegaly is a common finding. Rose spots (maculopapular erythematous lesions 2 mm in size that blanch with pressure) are frequently found on the upper abdomen (Baird-Parker, 1990; Grein et al, 1999; Barkin, 1985; Edelman & Levine, 1980; Drachman, 1974).
    2) CASE SERIES: Seven people developed typhoid fever after eating at an Indian buffet restaurant in Japan. Only 1 of the 7 patients had traveled to an endemic country (Nepal) 6 months earlier, but had no symptoms of typhoid fever upon his return. A Nepali chef of the Indian restaurant (index patient 8), who had contact with the salad in the restaurant, was suspected to be the carrier and the source of the outbreak, as he had moved from Nepal to Japan approximately 1.5 years earlier, and had conducted frequent travel between Nepal and Japan. Blood culture samples of all 7 patients were positive for Salmonella enterica Typhi. The mean incubation period was 17.4 days (ranging from 10 to 27 days). Symptoms included fever (n=7, 100%), diarrhea (n=6, 86%), abdominal pain (n=2, 29%), and vomiting (n=2, 29%). All 7 patients recovered with antibiotic therapy. The blood culture sample of the index patient was also positive for S. enterica Typhi and, although he remained asymptomatic, he was also treated with a course of antibiotic therapy (Kobayashi et al, 2016).

Genitourinary

    3.10.2) CLINICAL EFFECTS
    A) URINARY TRACT INFECTIOUS DISEASE
    1) WITH POISONING/EXPOSURE
    a) Rarely, Salmonella may cause a urinary tract infection, particularly in patients with an anatomical abnormality (Blaser & Reller, 1981).
    B) ACUTE RENAL FAILURE SYNDROME
    1) WITH POISONING/EXPOSURE
    a) Elevated serum creatinine levels can occur with S enteritides infections in the setting of massive volume loss and dehydration. Acute tubular necrosis has been described (Lalvani et al, 1997).
    C) NEPHRITIS
    1) WITH POISONING/EXPOSURE
    a) Focal nephritis developed in a 12-year-old boy with Salmonella oranienburg enteritis. Urinalysis revealed microscopic hematuria, mild proteinuria, and WBC sediments, while a CT scan showed enlargement of both kidneys (Nakano et al, 2002).
    D) DYSURIA
    1) WITH POISONING/EXPOSURE
    a) Difficulty in urinating and an ammonia smell to the urine were reported in 10% of patients (n=20) who developed salmonellosis following consumption of uncooked, frozen, processed chicken nuggets and strips (MacDougall et al, 2004).

Hematologic

    3.13.2) CLINICAL EFFECTS
    A) HEMATOLOGY FINDING
    1) WITH POISONING/EXPOSURE
    a) LEUKOCYTOSIS/LEUKOPENIA: The white blood cell count is usually increased in Salmonella infections, but can be low in cases of enteric (typhoid) fever.

Dermatologic

    3.14.2) CLINICAL EFFECTS
    A) MACULOPAPULAR ERUPTION
    1) WITH POISONING/EXPOSURE
    a) ROSE SPOTS: Erythematous, maculopapular lesions 2 to 4 mm in size that blanch with pressure are commonly noted on the upper abdomen and are associated with a Salmonella typhi infection.

Musculoskeletal

    3.15.2) CLINICAL EFFECTS
    A) ARTHRITIS
    1) WITH POISONING/EXPOSURE
    a) Postenteritis reactive arthritis and Reiter's syndrome may be observed after 3 to 4 weeks after the onset of acute symptoms (Center for Food Safety and Applied Nutrition (CFSAN), 2012; US Food and Drug Administration, 2009; Golding & Robertson, 1985). Patients with reactive arthritis may have joint inflammation, urethritis, uveitis, and/or conjunctivitis (Center for Food Safety and Applied Nutrition (CFSAN), 2012).
    b) Salmonella may cause septic arthritis, particularly in patients with sickle cell disease, hemoglobinopathies, or immunosuppression (Black et al, 1981).
    B) OSTEOMYELITIS
    1) WITH POISONING/EXPOSURE
    a) Osteomyelitis may complicate a Salmonella infection, particularly in patients with sickle cell disease or hemoglobinopathies (Black et al, 1981).
    C) MUSCLE PAIN
    1) WITH POISONING/EXPOSURE
    a) Myalgia may be noted (MacDougall et al, 2004; Keogh et al, 1984).

Laboratory Monitoring

Monitoring Parameters Levels

    4.1.1) SUMMARY
    A) Obtain a complete blood count to assess for leukocytosis, leukopenia, or anemia (in the setting of diarrheal blood loss).
    B) Blood cultures are indicated in children less than 1 year of age, immunocompromised patients, or patients who are clinically toxic.
    C) Stool cultures should be obtained to identify serotypes. Genetic identification of about 100 Salmonella serotypes from pure culture is now available. Traditional serotyping can be used to identify the remaining 2400-plus serotypes. Stool cultures should be obtained when a bacterial etiology of gastroenteritis is suspected. Indications include bloody diarrhea, high fever, toxic clinical appearance, prolonged course, immunocompromised host, or for epidemiologic purposes. Stool culture results can take 3 to 7 days. Due to the time involved with stool culture detection, treatment decisions should be based on the patient's presentation.
    4.1.2) SERUM/BLOOD
    A) Obtain a complete blood count to assess for leukocytosis, leukopenia, or anemia (in the setting of diarrheal blood loss).
    B) Blood cultures are indicated in children less than 1 year of age, immunocompromised patients, or patients who are clinically toxic.
    4.1.4) OTHER
    A) OTHER
    1) FECAL
    a) STOOL CULTURES: Stool cultures should be obtained to identify serotypes. Genetic identification of about 100 Salmonella serotypes from pure culture is now available. Traditional serotyping can be used to identify the remaining 2400-plus serotypes (Center for Food Safety and Applied Nutrition (CFSAN), 2012).
    b) Stool cultures should be obtained when a bacterial etiology of gastroenteritis is suspected. Indications include bloody diarrhea, high fever, toxic clinical appearance, prolonged course, immunocompromised host, or for epidemiologic purposes. Stool culture results can take 3 to 7 days. Due to the time involved with stool culture detection, treatment decisions should be based on the patient's presentation.
    1) The best clinical predictor of a positive stool culture for Salmonella is the combination of diarrhea persisting for more than 24 hours, fever (greater than 37.7 degrees C), and either blood in the stool or abdominal pain with nausea or vomiting (Koplan et al, 1980).
    c) FOOD ANALYSIS: Several methods to identify and detect Salmonella contamination in food have been developed. Although conventional culture and identification method may take 4 to 6 days to produce results, several rapid methods (1 to 2 days), including antibody and molecular (DNA or RNA) based assays are available (Center for Food Safety and Applied Nutrition (CFSAN), 2012). These methods are only used for epidemiologic investigation, not clinical management.
    d) FECAL LEUKOCYTES: Polymorphonuclear leukocytes are commonly found in stool examination of patients with bacterial diarrhea. In patients with a Salmonella infection, polymorphonuclear leukocytes will be noted on methylene blue smear in 80% to 100% of cases (Harris et al, 1972).

Treatment

Life Support

    A) Support respiratory and cardiovascular function.

Patient Disposition

    6.3.1) DISPOSITION/ORAL EXPOSURE
    6.3.1.1) ADMISSION CRITERIA/ORAL
    A) All patients with significant toxicity, severe dehydration, clinical instability, abnormal electrolyte concentrations, or baseline immunocompromised state should be admitted for intravenous rehydration and antibiotic therapy.
    6.3.1.2) HOME CRITERIA/ORAL
    A) Patients with mild diarrhea may be treated on an outpatient basis if compliance will be adequate; close follow-up care is essential.
    6.3.1.5) OBSERVATION CRITERIA/ORAL
    A) Patients with severe symptoms should be sent to a healthcare facility for evaluation and treatment.

Monitoring

    A) Obtain a complete blood count to assess for leukocytosis, leukopenia, or anemia (in the setting of diarrheal blood loss).
    B) Blood cultures are indicated in children less than 1 year of age, immunocompromised patients, or patients who are clinically toxic.
    C) Stool cultures should be obtained to identify serotypes. Genetic identification of about 100 Salmonella serotypes from pure culture is now available. Traditional serotyping can be used to identify the remaining 2400-plus serotypes. Stool cultures should be obtained when a bacterial etiology of gastroenteritis is suspected. Indications include bloody diarrhea, high fever, toxic clinical appearance, prolonged course, immunocompromised host, or for epidemiologic purposes. Stool culture results can take 3 to 7 days. Due to the time involved with stool culture detection, treatment decisions should be based on the patient's presentation.

Oral Exposure

    6.5.1) PREVENTION OF ABSORPTION/PREHOSPITAL
    A) Decontamination is not indicated.
    6.5.3) TREATMENT
    A) MONITORING OF PATIENT
    1) Obtain a complete blood count to assess for leukocytosis, leukopenia, or anemia (in the setting of diarrheal blood loss).
    2) Blood cultures are indicated in children less than 1 year of age, immunocompromised patients, or patients who are clinically toxic.
    3) Stool cultures should be obtained when a bacterial etiology of gastroenteritis is suspected. Indications include bloody diarrhea, high fever, toxic clinical appearance, prolonged course, immunocompromised host, or for epidemiologic purposes. Stool culture results can take 3 to 7 days. Due to the time involved with stool culture detection, treatment decisions should be based on the patient's presentation.
    B) FLUID/ELECTROLYTE BALANCE REGULATION
    1) GENERAL: Initial assessment must reflect the magnitude and type of dehydration. Rapid correction of deficits and careful monitoring of intake and output are essential.
    2) FLUIDS: Appropriate fluid therapy may need to be implemented prior to receiving the results of laboratory evaluation.
    a) ORAL FLUIDS: Patients with mild fluid deficits can often be managed with oral fluid therapy consisting of clear liquids or specially formulated solutions.
    b) IV FLUIDS: Patients with moderate to severe dehydration are generally treated with IV fluids.
    C) ANTIBIOTIC
    1) The use of antibiotics in patients with salmonellosis may increase the risk of the occurrence of bacteremia (Mermin et al, 1997a; Sirinavin & Garner, 1999).
    2) Antibiotics are not indicated for uncomplicated gastroenteritis because it may lead to emergence of resistant organisms (Spika et al, 1987), prolong the carrier state (Szanton, 1957; Aserkoff & Bennett, 1969; Dixon, 1965), increase the incidence of bacteremia (Mermin et al, 1997a; Sirinavin & Garner, 1999), and increase the risk of bacteriologic and symptomatic relapse (Guerrant et al, 2001).
    3) Antibiotics do not shorten the duration of diarrhea (Bengsston et al, 1955; Rowland, 1974; Sirinavin & Garner, 1999).
    4) INDICATIONS: Patients at risk of complicated course (neonates, infants, immunodeficiency, HIV, postsplenectomy, elderly); patients with bacteremia; dissemination with localized suppuration; any patient with systemic toxicity or dysenteric disease (Guerrant et al, 2001; DuPont, 1997; Pickering, 1991; Ashkenazi & Cleary, 1991).
    5) ANTIBIOTIC RESISTANCE: Strains of Salmonella which are resistant to a range of antimicrobials, including to fluoroquinolones, have emerged (World Health Organization (WHO), 2005; Cody et al, 1999; Villar et al, 1999).
    6) ANTIBIOTIC SELECTION
    a) CIPROFLOXACIN: ADULT DOSE: 500 mg orally twice daily for 5 to 7 days (14 days if immunocompromised). Contraindicated if the patient is less than 16 years of age or pregnant (Thielman & Guerrant, 2004).
    b) TRIMETHOPRIM AND SULFAMETHOXAZOLE: ADULT DOSE: 160 mg trimethoprim and 800 mg sulfamethoxazole orally twice daily for 5 to 7 days (14 days if immunocompromised). PEDIATRIC DOSE: 5 mg/kg trimethoprim and 25 mg/kg sulfamethoxazole orally twice daily for 5 to 7 days (14 days if immunocompromised) (Thielman & Guerrant, 2004).
    c) CEFTRIAXONE: ADULT DOSE: 100 mg/kg of body weight/day in 1 or 2 divided doses (Thielman & Guerrant, 2004).
    D) ANTIDIARRHEAL
    1) There is some evidence that antidiarrheal agents may adversely affect the course of salmonellosis (Sprinz, 1969).

Abstracts

Case Reports

    A) NOSOCOMIAL OUTBREAK
    1) The use of raw grade A eggs in the preparation of mayonnaise in a New York City hospital caused the largest nosocomial foodborne outbreak of Salmonella enteritidis infection in the United States; 42% of the patients were affected, with a fatality rate of 3% (Telzak et al, 1990).
    B) ADULT
    1) A 47-year-old man presented to the hospital with complaints of abdominal pain for 2 days, accompanied by watery diarrhea. No other family members were affected. Physical examination was normal except for tenderness in the right lower quadrant (RLQ). Stools were positive for occult blood. An abdominal ultrasonography revealed double concentric rings of sonolucency around a central echogenic core in the RLQ. A diagnosis of intussusception with a mass was confirmed. Preoperative stool cultures were positive only for the presence of Salmonella typhimurium colonies. The patient recovered with no adverse sequelae (Matsushita et al, 1994).
    C) PEDIATRIC
    1) A previously healthy 13-year-old boy died 37 hours after exposure to homemade ice cream contaminated with Salmonella typhimurium. The remaining ice cream contained 1 million Salmonella organisms/gram. The boy had eaten approximately 1 L of ice cream, or 1 billion organisms (Taylor et al, 1984).

Range Of Toxicity

Summary

    A) TOXICITY: INFECTIVE DOSE: Nontyphoidal salmonellosis: As low as 1 cell, depending on age and health of the patient and strain differences; typhoid fever: Less than 1000 cells. FATALITY RATE: Nontyphoidal salmonellosis: less than 1%; S. dublin: 15% when septicemic in the elderly; S. enteritidis: 3.6% in hospital/nursing home outbreaks. Typhoid fever: Up to 10% if untreated. Approximately 42% of patients over 50 years of age with confirmed Salmonella gastroenteritis required hospitalization in 2009, with a case-fatality rate of 1.3% in this age group.

Minimum Lethal Exposure

    A) FATALITY RATE
    1) Typhoid fever: Up to 10% if untreated. Nontyphoidal salmonellosis: less than 1%; S. dublin: 15% when septicemic in the elderly; S. enteritidis: 3.6% in hospital/nursing home outbreaks (Center for Food Safety and Applied Nutrition (CFSAN), 2012; US Food and Drug Administration, 2009).
    2) Approximately 42% of patients over 50 years of age with confirmed Salmonella gastroenteritis required hospitalization in 2009, with a case-fatality rate of 1.3% in this age group (Centers for Disease Control and Prevention, 2009; Centers for Disease Control and Prevention, 2008; Centers for Disease Control and Prevention, 2008a).
    B) CASE REPORT: A previously healthy 13-year-old boy died 37 hours after exposure to homemade ice cream contaminated with Salmonella typhimurium. The remaining ice cream contained 1 million Salmonella organisms/gram. The boy had eaten approximately 1 liter of ice cream or 1 billion organisms (Taylor et al, 1984).

Pharmacology Toxicology

Toxicologic Mechanism

    A) NONTYPHOIDAL SALMONELLOSIS: Salmonella organisms penetrate and enter the gut lumen into epithelium of small intestine, leading to inflammation and diarrhea. It has been suggested that enterotoxin may be produced, possibly within enterocytes (Center for Food Safety and Applied Nutrition (CFSAN), 2012).
    B) TYPHOID FEVER: Salmonella organisms penetrate and enter the gut lumen into epithelium of small intestine, resulting in severe inflammation and diarrhea. It may also enter the bloodstream causing systemic disease (ie, septicemia). It has been suggested that enterotoxin may be produced, possibly within enterocytes (Center for Food Safety and Applied Nutrition (CFSAN), 2012).

Animal Toxicology

Clinical Effects

    11.1.6) FELINE/CAT
    A) Cats may be fecal carriers of Salmonella without displaying clinical signs. The incidence ranges from 1 to 18% of cats. Chronic nonspecific illness, characterized by fever, anorexia, and left shift leukogram were seen in three cats. Gastroenteritis (vomiting, diarrhea) was noted in three cats (Dow et al, 1989).

Treatment

    11.2.2) LIFE SUPPORT
    A) GENERAL
    1) MAINTAIN VITAL FUNCTIONS: Secure airway, supply oxygen, and begin supportive fluid therapy if necessary.
    11.2.5) TREATMENT
    A) CAT
    1) First choice antimicrobial agents include ampicillin, amoxicillin, or cotrimoxazole. Chloramphenical may cause adverse hematologic effects in cats, and should be avoided (Dow et al, 1989).

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