5343. Bacterial culture. Feces (pathogenic intestinal flora: Salmonella enterica, Shigella spp.). Antimicrobial resistance profile with MIC (if pathogenic microflora is detected)

Stool culture for pathogenic intestinal microflora is a microbiological test that allows the detection of Salmonella enterica and Shigella spp. in a stool sample.

If pathogenic microorganisms are detected, an antibiotic susceptibility test with MIC (minimal inhibitory concentration) is performed to determine antibiotic effectiveness and select targeted therapy. It is advisable to combine this analysis with a coprogram (to assess inflammatory components) and PCR testing for intestinal infections in complex cases.

Automated identification of microorganisms is performed using MALDI-TOF mass spectrometry on the MALDI Biotyper sirius IVD System analyzer (Bruker, Germany).

Pathogenic intestinal microflora refers to bacteria that can cause infectious diseases of the gastrointestinal tract. Unlike the normal microflora, which supports digestion, pathogenic microorganisms cause inflammation, intoxication, and disruption of intestinal function.

The most common pathogens are:

Salmonella spp. – causes salmonellosis;

Shigella spp. – causes bacterial dysentery (shigellosis).

Infection occurs through contaminated food (meat, eggs, dairy products), unsafe water, or contact with infected surfaces or people. Intestinal infections manifest as fever, diarrhea, abdominal pain, bloating, and the presence of mucus or blood in stool.

Bacteriological stool culture is used for diagnosing intestinal infections, monitoring treatment effectiveness, and screening for bacterial carriage.

Carriage is a condition in which a person excretes bacteria without symptoms but can still spread the infection. It may be transient or persistent and is especially concerning in childcare facilities, healthcare institutions, and food service environments.

For S. typhi or S. paratyphi, carriage may persist for weeks or months after salmonellosis. Chronic carriage is defined as bacterial excretion lasting more than 12 months. Clinically significant carriage is confirmed by repeated detection of ≥10⁵ CFU/g of stool.

Carriage of Shigella spp. is less common, but even low titers (10³–10⁴ CFU/g) may be epidemiologically important due to high contagiousness.

The analysis allows identification and quantification of pathogens, and when sufficient bacterial counts are detected, automated antibiotic susceptibility testing is performed according to EUCAST and CLSI standards.

Note: In suspected carriage cases, serial testing (2–3 samples collected several days apart) is recommended. Self-medication is not advised; consultation with an infectious disease specialist is required after obtaining results.

Indications include:

• Various types of biological material depending on the test