Intestinal Permeability Flashcards
Molecular mimicry examples
Klebsiella and Ankylosing Spondylitis
• Streptococcus and Rheumatic Heart Fever
• Proteus and Rheumatoid arthritis
• Many other intestinal microbes have been implicated in systemic
disease: Salmonella, Shigella, Campylobacter, Yersinia, Proteus.
toll like receptors
TLRs act as gates (tolls!) for controlling the immune system.
• TLRs react to gut flora and bacterial DNA, recognizing them
as normal or foreign.
• Crohn’s disease more commonly has the NOD2 portion of
TLR altered, leading to an increase in the NF-κB-induced
inflammation.
Apply select laboratory tools that can help reveal and track
intestinal permeability.
mannitol/lactulose ratio
anti-zonulin/occludin Ab
anti-LPS Ab
actinomycin IgA
Apply select laboratory tools that can help reveal and track
inflammation and oxidative stress in the gastrointestinal tract.
- Calprotectin
- Lactoferrin
- Secretory IgA (sIgA)
- Lysozyme
- Eosinophilic Protein X
8OHdG - marker of oxidative stress
low mannitol and low lactulose
malabsorption
low mannitol and high lactulose
IP and malabsorption
how to test zonulin
with anti-zonulin antibodies - more stable than zonulin
Calprotectin & Lactoferrin
proteins released by PMNs
Reliable markers for the presence of infectious, inflammatory, or
malignant disease
best if checked in stool
Calprotectin & Lactoferrin elevated in
- IBD
- Postinfectious IBS
- Cancer of the gastrointestinal tract
- Certain gastrointestinal infections
- NSAID enteropathy
- Food allergy
- Chronic pancreatitis
Fecal Calprotectin (vs. lactoferrin)
slightly better Reliable Non invasive Discrimination between IBD and IBS
SIgA
• Secretory IgA production is increased in the presence of potentially harmful antigens such as pathogenic bacteria, parasites, yeast, viruses, abnormal cell antigens, and allergenic proteins.
Elevated fecal sIgA is useful in identifying if bacteria, yeast, or parasites are present. SIgA should renormalize with eradication of the pathogenic microorganisms.
•However, sIgA production may be suppressed in cases of mental or physical stress, or inadequate nutrition. Dietary restrictions, excessive alcohol intake, body mass loss, negative mood, and anxiety have been associated with lowered sIgA production
• sIgA may be a good marker of overall Nutritional Status (if low = poor status)
•May be a good marker of overtraining in athletes
•May be a good general marker of “Infection” in the gut
fecal lysozyme
One of many antimicrobial peptides that attack bacterial cell walls; nonspecific innate protection One of many antimicrobial peptides that attack bacterial cell walls; nonspecific innate protection for the determination of colonic inflammatory activity. High levels of fecal lysozyme (>2,000) may be suggestive of IBD.
Eosinophil Protein X
The measurement of eosinophil granule-derived proteins in feces
is useful for evaluating disease activity and predicting relapse in
patients with IBD
Fecal calprotectin provides superior discrimination to EPX in IBD
treatment outcome.
calprotectin levels
if fecal calprotecin <50, r/o IBD
If >200, inflamm is present, needs further wu for IBD
calprotectin and food allergy
elevated
