Salmonellosis
Salmonellosis: Excerpt from Professional Guide to Diseases (Eighth Edition)
A common infection in the United States, salmonellosis is caused by gram-negative bacilli of the genus Salmonella, a member of the Enterobacteriaceae family. It occurs as enterocolitis, bacteremia, localized infection, typhoid, or paratyphoid fever. Nontyphoidal forms usually produce mild to moderate illness with low mortality. (See Types of salmonellosis, page 188.)
Typhoid, the most severe form of salmonellosis, usually lasts from 1 to 4 weeks. Mortality is about 3% in patients who are treated. In those who are untreated, 10% of cases result in fatality, usually as a result of intestinal perforation or hemorrhage, cerebral thrombosis, toxemia, pneumonia, or acute circulatory failure. An attack of typhoid confers lifelong immunity, although the patient may become a carrier. Salmonellosis is 20 times more common in patients with acquired immunodeficiency syndrome. Features are increased incidence of bacteremia, inability to identify the infection source, and tendency of infection to recur after therapy is stopped.
Causes and incidence
Of an estimated 1,700 serotypes of Salmonella, 10 cause the diseases most common in the United States; all 10 can survive for weeks in water, ice, sewage, or food. Nontyphoidal salmonellosis generally follows the ingestion of contaminated or inadequately processed foods, especially eggs, chicken, turkey, and duck. Proper cooking reduces the risk of contracting salmonellosis. Other causes include contact with infected people or animals or ingestion of contaminated dry milk, chocolate bars, or drugs of animal origin. Salmonellosis may occur in children younger than age 5 from fecal-oral spread. Enterocolitis and bacteremia are common (and more virulent) among infants, elderly persons, and people already weakened by other infections; paratyphoid fever is rare in the United States.
Typhoid usually results from drinking water contaminated by excretions of a carrier or from ingesting contaminated shellfish. (Contamination of shellfish occurs by leakage of sewage from offshore disposal depots.) Most typhoid patients are younger than age 30; most carriers are women older than age 50. Incidence of typhoid in the United States is increasing as a result of travelers returning from endemic areas.
Signs and symptoms
Clinical manifestations of salmonellosis vary but usually include fever, abdominal pain, and severe diarrhea with enterocolitis. Headache, increasing fever, and constipation are more common in typhoidal infection.
Diagnosis
Generally, diagnosis depends on isolation of the organism in a culture, particularly blood (in typhoid, paratyphoid, and bacteremia) or feces (in enterocolitis, paratyphoid, and typhoid). Other appropriate culture specimens include urine, bone marrow, pus, and vomitus. In endemic areas, clinical symptoms of enterocolitis allow a working diagnosis before the cultures are positive. The presence of Salmonella typhi in stool 1 or more years after treatment indicates that the patient is a carrier, which is true of 3% of patients.
Widal’s test, an agglutination reaction against somatic and flagellar antigens, may suggest typhoid with a fourfold rise in titer. However, drug use or hepatic disease can also increase these titers and invalidate test results. Other supportive laboratory values may include transient leukocytosis during the 1st week of typhoidal salmonellosis, leukopenia during the 3rd week, and leukocytosis in local infection.
Treatment
Antimicrobial therapy for typhoid, paratyphoid, and bacteremia depends on organism sensitivity. It may include amoxicillin, chloramphenicol and, in severely toxemic patients, co-trimoxazole, ciprofloxacin, or ceftriaxone. Localized abscesses may also need surgical drainage. Enterocolitis requires a short course of antibiotics only if it causes septicemia or prolonged fever. Other treatments include bed rest and fluid and electrolyte replacement. The administration of camphorated opium tincture, kaolin with pectin, diphenoxylate, codeine, or small doses of morphine may be necessary to relieve diarrhea and control cramps in patients who must remain active.
Special considerations
❑All infections caused by Salmonella must be reported to the state health department.
❑Follow contact precautions if the patient is incontinent or diapered; otherwise, standard precautions are appropriate. Always wash your hands thoroughly before and after any contact with the patient, and advise other facility personnel to do the same. Teach the patient to use proper hand hygiene, especially after defecating and before eating or handling food. Wear gloves and a gown when disposing of feces or fecally contaminated objects. Continue precautions until three consecutive stool cultures are negative — the first one taken 48 hours after antibiotic treatment ends, followed by two more at 24-hour intervals.
❑Observe the patient closely for signs and symptoms of bowel perforation from erosion of intestinal ulcers: sudden pain in the lower right side of the abdomen and abdominal rigidity, possibly after one or more rectal bleeding episodes; sudden fall in temperature or blood pressure; and rising pulse rate (indicating shock).
❑During acute infection, plan care and activities to allow the patient as much rest as possible. Raise the side rails and use other safety measures, because the patient may become delirious. Assign him a room close to the nurses’ station so he can be checked often. Use a room deodorizer (preferably electric) to minimize odor from diarrhea and to provide a comfortable atmosphere for rest.
❑Accurately record intake and output. Maintain adequate I.V. hydration. When the patient can tolerate oral feedings, encourage high-calorie fluids such as milkshakes. Watch for constipation.
❑Provide good skin and mouth care. Turn the patient frequently, and perform mild passive exercises, as indicated. Apply mild heat to the abdomen to relieve cramps.
❑Don’t administer antipyretics. These mask fever and lead to possible hypothermia. Instead, to promote heat loss through the skin without causing shivering (which keeps fever high by vasoconstriction), apply tepid, wet towels (don't use alcohol or ice) to the patient's groin and axillae. To promote heat loss by vasodilation of peripheral blood vessels, use additional wet towels on the arms and legs, wiping with long, vigorous strokes.
❑After draining the abscesses of a joint, provide heat, elevation, and passive range-of-motion exercises to decrease swelling and maintain mobility.
❑If the patient has positive stool cultures on discharge, tell him to be sure to wash his hands after using the bathroom and to avoid preparing uncooked foods, such as salads, for family members. He also should'nt work as a food handler until cultures are negative.
❑To prevent salmonellosis, advise the patient to refrigerate meat and cooked foods promptly and to avoid raw eggs or beverages mixed with raw eggs. Also teach the importance of proper hand hygiene. Advise those at high risk for contracting typhoid (laboratory workers or travelers) to seek vaccination.
Pictures
Book Source Details
- Book Title: Professional Guide to Diseases (Eighth Edition)
- Author(s): Springhouse
- Year of Publication: 2005
- Copyright Details: Professional Guide to Diseases (Eighth Edition), Copyright © 2005 Lippincott Williams & Wilkins.
More About Salmonella food poisoning
More Medical Textbooks Online about Salmonella food poisoning
Review other book chapters online related to Salmonella food poisoning:
Medical Books Excerpts
- Vomiting
- "In A Page: Pediatric Signs and Symptoms" (2007)
- [ read ]
- Vomiting
- "Handbook of Signs & Symptoms (Third Edition)" (2006)
- [ read ]
- Poisoning
- "Professional Guide to Diseases (Eighth Edition)" (2005)
- [ read ]
- Vomiting
- "Professional Guide to Signs & Symptoms (Fifth Edition)" (2006)
- [ read ]
- Nausea and Vomiting
- "The 10-Minute Diagnosis Manual: Symptoms and Signs in the Time-Limited Encounter" (2000)
- [ read ]
- Vomiting
- "Alarming Signs and Symptoms: Lippincott Manual of Nursing Practice Series" (2007)
- [ read ]
- Vomiting
- "Signs & Symptoms: A 2-in-1 Reference for Nurses" (2007)
- [ read ]
- Vomiting
- "Nursing: Interpreting Signs and Symptoms" (2007)
- [ read ]
Copyright notice for book excerpts: Copyright © 2008 Lippincott Williams & Wilkins. All rights reserved.
» Next page: Poisonous snakebite (Professional Guide to Diseases (Eighth Edition))
Rate This Website
What do you think about the features of this website?
Take our user survey and have your say:
Website User Survey
Medical Tools & Articles:
Next articles:
Tools & Services:
Medical Articles:
Forums & Message Boards
- Ask or answer a question at the Boards:
