Escherichia coli (E. coli) bacteria are part of healthy digestive systems, but some strains produce poisons called Shiga toxins that can cause severe diarrhea and hemolytic uremic syndrome (HUS). Lab tests can detect these disease-causing E. coli to help diagnose an infection.
A stool culture helps diagnose an infection of the digestive system when a person has diarrhea, abdominal pain, cramping, and blood or mucus in the stool.
Tests for antineutrophil cytoplasmic antibodies (ANCA, pANCA, cANCA, MPO, PR3) may be used to help diagnose autoimmune disorders, such as vasculitis or inflammatory bowel disease.
A urine culture is used to diagnose a urinary tract infection (UTI) and to identify the bacteria or yeast causing the infection so it can be treated. A urine culture may be ordered when a person has symptoms such as a frequent urge to urinate and pain and burning when urinating.
Calprotectin is released by white blood cells (neutrophils) in the digestive tract with inflammation. Calprotectin tests measure levels in stool to help detect conditions such as inflammatory bowel disease (IBD) and infections.