Stool Culture and Sensitivity

Function

The Stool Culture and Sensitivity test is a primary diagnostic tool used to identify the presence of pathogenic bacteria in the digestive tract. Unlike the normal flora that resides in the gut and aids digestion, pathogenic bacteria can cause acute or chronic gastrointestinal distress. The 'Sensitivity' portion of the test determines which specific antibiotics are most effective at inhibiting the growth of the identified pathogen.

Why it is Ordered

Physicians typically order this test when a patient presents with symptoms of a gastrointestinal infection (gastroenteritis). These symptoms include:

• Persistent or severe diarrhea (which may be bloody or mucoid).
• Abdominal cramping and pain.
• Nausea and vomiting.
• Fever and fatigue. It is especially critical for patients who have recently traveled internationally, consumed potentially contaminated food or water, or have been in contact with others experiencing similar symptoms.

Associated Conditions

Several specific bacterial pathogens are targeted during this screen, including:

• Salmonella: Often linked to contaminated poultry or eggs.
• Shigella: Highly contagious and often causes dysentery.
• Campylobacter: One of the most common causes of bacterial diarrhea worldwide.
• Escherichia coli (STEC): Specifically the Shiga toxin-producing strains like O157:H7.
• Vibrio: Often associated with raw or undercooked seafood.

By identifying the specific bacterium, healthcare providers can prevent the spread of infection (public health reporting) and avoid the misuse of antibiotics, as some GI infections are self-limiting or may even be worsened by certain antibiotic treatments.