Topical diagnosis of intestinal infections

Clinical presentation and diagnosis of large intestine lesions

Topical diagnosis of intestinal infections is based on taking an anamnesis and a detailed study of the disease history. When the distal large intestine is affected, a characteristic colitis syndrome develops. Its diagnosis includes the assessment of intoxication (malaise, fever) and pain syndrome, with pain clearly localized in the lower half of the abdomen.

Specific markers of distal involvement are tenesmus and frequent false urges to defecate. The most important diagnostic criterion is the nature of the stool: it becomes frequent, liquid, and contains visible pathological impurities such as mucus and blood.

The dynamics of the disease are also of key importance: the physician must take into account the presence of a prodromal period and the variant of disease onset (it can be typical, influenza-like, or spastic-painful). The evolution of diarrhea in the colitis variant is characterized by a gradual change: initially, the stool is voluminous, semi-formed, or mushy, after which its properties transform.

Etiotropic therapy: selection of antimicrobial agents

Etiotropic therapy is prescribed for moderate and severe infections (predominantly in the colitis variant). The drugs of choice are fluoroquinolones, such as ciprofloxacin and norfloxacin, as well as their analogues. Alternative regimens include nitrofurans (e.g., furazolidone) and third-generation cephalosporins (cefotaxime). The duration of antibiotic therapy ranges from 5 to 7 days at average therapeutic doses.

Special attention should be paid to nalidixic acid derivatives (oxolinic acid / Neggram). These drugs are used exclusively in children, due to restrictions on the use of fluoroquinolones in pediatric practice. This group of drugs is absolutely not used in adult patients. This is due to the fact that adults rapidly develop cross-resistance to all quinolones, including modern fluorinated agents.

Pathogenetic treatment: rehydration and detoxification

Detoxification and rehydration therapy is a crucial component of treatment, the principles of which are similar to the management of patients with foodborne toxic infections, salmonellosis, and cholera. A comprehensive approach necessarily implies combining antimicrobial agents with adequate hydration.

• In moderate intoxication and mild dehydration: oral administration of glucose-salt solutions (Regidron) is sufficient.
• In severe intoxication: intravenous administration of a 5% glucose solution and Reopolyglucukin is indicated.
• In severe dehydration (characteristic of gastroenterocolitic and gastroenteritic variants), a strict rule applies: prior to the administration of any colloidal solutions, intensive intravenous rehydration with polyionic (crystalloid) solutions (Quartasol, Trisol, Chlosol) must be performed.

The volume of such an infusion is calculated individually, based on the degree of dehydration and the patient's pre-illness body weight, averaging from 2 to 5 liters. In critical situations, with the threat or development of infectious-toxic shock, glucocorticosteroids are immediately included in the intensive care regimen.

Restoration of intestinal function: enzymes and eubiotics

After completing a course of antibiotic therapy, patients may develop intestinal dysbiosis. Its main clinical manifestations are the lack of stable stool normalization and long-lasting abdominal pain. To eliminate these symptoms, the administration of probiotics and eubiotics (biosporin, lactobacterin, bificol, bifidumbacterin forte, probifor) is indicated.

Notably, in mild forms of shigellosis, the prescription of probiotics can act as the main, isolated treatment method without the use of antibacterial agents. Additionally, to correct digestive function, enzyme preparations are included in the complex therapy regimen: digestal, mezim forte, panzinorm, festal, holenzym, or orase.

Criteria for recovery and follow-up

Patients who have undergone acute intestinal infections (including bacteriologically unconfirmed shigellosis) are discharged only after complete clinical recovery. A strict clinical criterion is discharge no earlier than 3 days after stable normalization of body temperature and stool.

Bacteriological monitoring is carried out after the end of treatment: stool collection is allowed no earlier than 2 days after discontinuing antibiotics. For most patients, a single negative culture is sufficient. For decreed groups (food industry workers, water supply workers, and children from preschool institutions), the rules are stricter:

1. For an unconfirmed diagnosis — a single examination.
2. For a confirmed Shigella isolation — a double examination with an interval of 1–2 days.

Discharged food industry and water supply workers are subject to mandatory follow-up in outpatient clinics for 3 months to monitor their condition and clearance for work.

Class and exam questions

What else to study on this topic

• Features of the course of influenza-like and spastic-painful variants of intestinal infections.
• Differences in the clinical presentation of gastroenterocolitic and gastroenteritic variants.
• Mechanisms of development of infectious-toxic shock and the role of glucocorticosteroids in its management.
• Tactics of follow-up for bacterial carriers in food enterprises.
• The mechanism of cross-resistance formation to quinolones.

Other topics in the "Acute Intestinal Infections" section

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