From the Guidelines
Fecal leukocytes are also known as pus cells in stool. These are white blood cells that can be found in stool samples during laboratory examination, as noted in the 2017 infectious diseases society of America clinical practice guidelines for the diagnosis and management of infectious diarrhea 1. Their presence indicates inflammation in the gastrointestinal tract, often due to bacterial infections. When these pathogens invade the intestinal mucosa, the body responds by sending white blood cells to fight the infection, which then appear in the stool. Some key points to consider about fecal leukocytes include:
- Fecal leukocyte examination may be used to differentiate inflammatory diarrhea from secretory diarrhea, but it performs poorly to establish the infectious cause of diarrhea, especially among inpatients 1.
- Lactoferrin has been used as a surrogate marker for fecal leukocytes as it is not degraded during transport and processing 1.
- Calprotectin is a protein released in large quantities by granulocytes during inflammatory processes and is an established marker of intestinal inflammation used in patients with IBD, but its value in acute infectious diarrhea is still being studied 1. Fecal leukocyte testing is a simple screening method that can help differentiate between inflammatory and non-inflammatory causes of diarrhea. The test involves examining a stained stool sample under a microscope to identify these white blood cells. A positive result suggests an inflammatory or invasive process, while their absence may point to viral or non-inflammatory causes of gastrointestinal symptoms.
From the Research
Fecal Leukocytes
- Fecal leukocytes are also known as white blood cells in stool, and they can be an indicator of inflammatory diarrhea 2, 3, 4, 5.
- Another name for fecal leukocytes is not explicitly stated in the provided studies, but lactoferrin is mentioned as a marker for fecal leukocytes 2, 3, 5.
- Lactoferrin is a protein found in fecal leukocytes, and its presence can be used to detect intestinal inflammation 2, 3, 5.
- The studies suggest that fecal lactoferrin can be a useful marker for fecal leukocytes, especially when the leukocytes are morphologically lost or destroyed 2.
- Other leukocyte proteins, such as calprotectin, lysozyme, myeloperoxidase, and PMN-elastase, can also be found in feces and may be used to differentiate between inflammatory bowel disease and irritable bowel syndrome 6.