General intoxication syndrome and temperature response
The clinical presentation of the disease directly depends on the severity grade, which primarily reflects the intensity of intoxication and fever.
In mild cases, the temperature response remains moderate: thermometer readings do not exceed 38°C. The general condition is mildly affected, and appetite is only slightly decreased. Nervous system manifestations may occasionally include only mild weakness.
Moderately severe cases are characterized by more pronounced fever. Body temperature ranges from 38°C to 39°C and typically persists for two to five days. During this period, the patient's appetite is either significantly reduced or completely absent. Neurological symptoms become more noticeable: patients complain of general weakness, adynamia, increased irritability, and headache.
In severe cases, body temperature exceeds 39°C. Appetite is completely lost. Intoxication reaches extreme degrees, manifested by sharp weakness, apathy, and profound sleep disorders. Patients suffer from headaches, hiccups, and convulsions; in the most critical situations, coma may develop.
Gastrointestinal tract involvement
Local manifestations of the disease also strictly correlate with its severity, manifesting as changes in the nature of pain, stool frequency, and the state of the sigmoid colon.
- Mild form: Patients experience diffuse, mild abdominal pain. False urges to defecate and tenesmus are completely absent. On palpation, the sigmoid colon is moderately dense and tender. Stool frequency ranges from 3–5 to 10 times per day, and visually, only mucus is detected as a pathological admixture.
- Moderately severe form: Pain syndrome intensifies — pain becomes severe and cramping in nature. Patients develop false urges, although tenesmus is still absent. On palpation, the sigmoid colon is distinctly dense and tender. Defecation frequency increases from 10 to 25 times per day. Blood appears in the stool alongside mucus.
- Severe form: Abdominal pain is described as agonizing and cramping, clearly localized in the lower abdomen. Both exhausting false urges and pronounced tenesmus are present. The sigmoid colon is in a state of severe spasm and is extremely tender. Stool frequency exceeds 25–30 times per day; the stool is abundantly mixed with mucus and blood.
Changes in the cardiovascular system
Hemodynamic disorders are an important marker of process severity. While clinically significant cardiovascular changes are not observed in mild cases, the situation changes drastically as the disease progresses.
In moderately severe cases, unstable relative tachycardia is registered. Systolic blood pressure remains above 100 mm Hg. Against the background of these changes, skin pallor and dizziness are noted.
Severe cases are accompanied by absolute persistent tachycardia. A critical drop in systolic blood pressure occurs — below 80 mm Hg (in patients with baseline hypertension, this figure may be less than 100–110 mm Hg). Shortness of breath and pronounced cyanosis develop, indicating severe tissue hypoxia.
Laboratory and endoscopic indicators
Objective diagnostics confirm clinical observations. Coprocytoscopy in mild cases reveals erythrocytes and leukocytes in amounts up to 15–25 per high-power field. In moderately severe cases, their number exceeds 40, while in severe cases, erythrocytes and leukocytes completely cover all visual fields.
Changes in the complete blood count:
- Mild form: Moderate leukocytosis occurs in only 30% of cases.
- Moderately severe form: Leukocytosis is detected in 50% of cases and is accompanied by a pronounced left shift in the leukocyte formula.
- Severe form: Characterized by massive leukocytosis (>12–15 × 10³/µL), neutrophilia, a sharp shift down to immature forms, the appearance of toxic granulation of neutrophils, and a significant increase in ESR.
Endoscopic picture (sigmoidoscopy): In mild cases, diffuse catarrhal inflammation of the mucosa with isolated hemorrhages and erosions is visualized. Moderately severe cases are also characterized by diffuse catarrhal inflammation, but multiple hemorrhages, erosions, and ulcers are typical. In severe cases, fibrinous inflammation joins the aforementioned changes (hemorrhages, ulcers).
Complete clinical recovery of patients with a mild course occurs by the 2–3rd week from the onset of the disease. In the moderately severe form, this process drags on to the 4–5th week. In patients who have suffered a severe form of the disease, recovery occurs no earlier than 4–6 weeks from the moment of symptom manifestation.
Briefly: answers to topical questions
What antibacterial drugs are the drugs of choice for etiotropic therapy of shigellosis?
The drugs of choice for etiotropic therapy of shigellosis are fluoroquinolones: ciprofloxacin, norfloxacin, and their analogs.
Alternative drugs:
- nitrofurans — furazolidone;
- third-generation cephalosporins — cefotaxime.
Nalidixic acid derivatives (Negram, Nevigramon) are used only in children; they are not used in adults due to the rapid development of cross-resistance to all quinolones.
When choosing a drug and regimen, regional antibiotic susceptibility of shigellae, the clinical variant, and the severity of the disease are taken into account.
Is there specific vaccine prevention for shigellosis, and what vaccines are used?
Yes. In the Russian Federation, specific vaccine prevention is represented by the vaccine against Sonne dysentery (Shigella sonnei) — "Shigellvac", a purified LPS of the S. sonnei culture.
There are currently no WHO-recommended vaccines for the prevention of shigellosis.
Post-vaccination immunity is species-specific, protects only against S. sonnei, and lasts for 1 year.
Vaccination is recommended for individuals traveling to regions with high incidence of Sonne dysentery or regions epidemiologically unfavorable for dysentery, public catering or food industry workers, communal service workers, infectious disease hospitals, and bacteriological laboratories. Vaccination is also carried out according to epidemiological indications in the event of an epidemic or outbreak threat and during an epidemic.
What are the rules for collecting stool for bacteriological confirmation of a shigellosis diagnosis?
For the bacteriological method, the patient's excrement serves as the material. Sources also indicate vomit, gastric lavage water, and bile; in case of suspected generalized form, blood and bone marrow are additionally examined.
Specific rules for the initial collection of stool for bacteriological confirmation of the diagnosis are not detailed in the cited sources.
For the follow-up bacteriological examination of stool after treatment, the rule is specified: material collection is carried out no earlier than 2 days after the end of the antibiotic therapy course.
To remember stool admixtures: Mild form — MUCUS only; Moderate and Severe — MUCUS + BLOOD (as mucosal damage progresses).
Class and exam questions
What is the main difference in pain syndrome between mild and severe forms?
In the mild form, pain is diffuse and mild; false urges and tenesmus are absent. In the severe form, pain is agonizing, cramping, localized in the lower abdomen, and accompanied by pronounced false urges and tenesmus.
How does blood pressure change in the severe course of the disease?
A significant decrease occurs: systolic blood pressure drops below 80 mm Hg, and in hypertensive patients — below 100–110 mm Hg.
What changes are found in the complete blood count in the severe form?
Pronounced leukocytosis (>12–15 × 10³/µL), neutrophilia, a sharp shift in the leukocyte formula to immature forms, toxic granulation of neutrophils, and an increase in ESR are detected.
What else to study on this topic
- Pathogenesis of the development of fibrinous inflammation
- Mechanisms of formation of toxic granulation in neutrophils
- Causes of blood pressure drop in severe form
- Differential diagnosis of causes of mucus and blood in the stool
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