Etiology and transmission routes
The etiological structure of the disease varies depending on the child's age.
- In children under one year of age, S. typhimurium dominates. This pathogen frequently causes nosocomial outbreaks, and transmission occurs predominantly via contact-and-household routes.
- In older children, S. enteritidis prevails. In this case, the infection is transmitted via food, most commonly through the consumption of infected eggs or poultry meat.
The urgency of the problem is sustained by the spread of multidrug-resistant hospital strains.
Symptoms in infants in the first year of life
In infants, the disease begins subacutely or gradually, reaching its peak by days 3–7. A prolonged and relapsing course is characteristic.
The intoxication syndrome develops gradually: fever, lethargy, pallor, decreased appetite, and tachycardia appear. Gastrointestinal tract involvement manifests as enterocolitis or gastroenterocolitis:
- Persistent vomiting, which may start immediately or join later.
- Stool is abundant, loose, or watery, but retains its fecal character. A specific sign is a green-brown color (“swamp mud” sign). Blood admixtures appear late (on days 5–7).
- Associated symptoms: severe flatulence and hepatosplenomegaly.
The severity of the condition in such children depends on the level of intoxication and the stage of exicosis (dehydration). There is a high risk of infection generalization with the formation of purulent foci (e.g., meningitis, pneumonia, osteomyelitis). During the recovery period, bacterial carriage lasting up to a year is possible.
Features in older children
In older children, the disease begins acutely and runs a milder course than in infants. The main clinical variant resembles food-borne toxicoinfection.
Febrile fever is noted. Pain syndrome is moderate, localized in the epigastric and periumbilical regions. In about half of the patients, vomiting is observed, often persistent (1–3 times a day).
Clinical forms of intestinal infection
Several variants of the clinical course are distinguished, determining the clinical picture.
Gastrointestinal forms Begin acutely, accompanied by fever up to 38–40 °C for 1–5 days and severe intoxication. Dyspeptic syndrome includes moderate abdominal pain, repeated vomiting, and abundant loose stool with pathological admixtures. Hepatosplenomegaly is not typical for this form. A severe course threatens with the development of exicosis and cardiovascular failure.
Typhoid-like form Distinguished by prolonged fever (10–14 days), which can be constant or relapsing. Sharp intoxication is characteristic: adynamia, lethargy, sleep disorders, severe headache, arthralgia, and myalgia. Examination reveals bradycardia, arterial hypotension, abdominal distension, and hepatosplenomegaly. The stool may be pathological, but constipation sometimes occurs. Leukopenia is observed in the blood.
Class and exam questions
At what age does salmonellosis run the most severe course?
Children under 1 year of age are at risk; in them, the infection often runs a severe, relapsing course with a high risk of generalization and formation of purulent foci.
What kind of stool is characteristic of infants with this infection?
Stool is abundant, loose, retaining its fecal character, often green-brown in color ("swamp mud" appearance).
What does the severity of the condition depend on in salmonellosis?
The severity of the disease is directly determined by the severity of toxicosis and the degree of exicosis (dehydration).
What else to study on this topic
- Criteria for degrees of exicosis (grades I–III)
- Pathogenesis of secondary purulent foci formation during infection generalization
- Mechanisms of multidrug resistance in hospital strains
- Features of bacterial carriage during the convalescence period
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