The term "dysbacteriosis" is familiar to many people. It is often used to explain bloating, irregular bowel movements, discomfort after taking antibiotics, or even skin rashes. However, in modern evidence-based medicine, the situation is far more complex.
Today, dysbacteriosis is not recognized as an independent medical diagnosis that can be established solely on the basis of a stool test or a set of nonspecific symptoms. Instead, the term "dysbiosis" is increasingly used. Dysbiosis refers to a condition in which the composition, diversity, or functional activity of the microbiota is altered. It is not a disease itself but rather a possible accompanying factor or consequence of various pathological processes.
Why Has the Term "Dysbacteriosis" Been Abandoned?
Historically, the concept of dysbacteriosis emerged when scientific knowledge about the gut microbiota was still limited. At that time, it was believed that there was an "ideal" bacterial composition and that any deviation from it represented a disease.
Modern research has shown that this is not the case.
Each person's microbiota is unique. Its composition is influenced by age, mode of birth, diet, genetics, medication use, previous infections, and many other factors. What is considered normal for one individual may differ substantially from what is normal for another.
For this reason, it is currently impossible to define a universal "reference" microbiota against which every patient can be compared.
What Is Dysbiosis?
Dysbiosis is an imbalance of the microbial ecosystem that may be characterized by:
- reduced bacterial diversity;
- changes in the relative abundance of specific microorganisms;
- impaired microbiota functions;
- decreased production of beneficial metabolites;
- altered interactions between the microbiota and the immune system.
It is important to understand that dysbiosis itself does not explain the cause of a disease. It may be either a consequence of an underlying pathological process or one of the factors contributing to its persistence.
Can a Stool Test Diagnose Dysbacteriosis?
No.
Even modern microbiota analysis methods, including next-generation sequencing (NGS), cannot establish a diagnosis of "dysbacteriosis."
The results of such studies help evaluate the characteristics of the microbial ecosystem but must always be interpreted together with the patient's clinical presentation, medical history, lifestyle, and the results of other examinations.
Treating a laboratory report alone is not appropriate.
When Do Changes in the Microbiota Really Matter?
Scientific studies have demonstrated associations between dysbiosis and many conditions, including:
- irritable bowel syndrome;
- inflammatory bowel disease;
- Clostridioides difficile infection;
- obesity;
- metabolic syndrome;
- certain allergic and autoimmune diseases.
However, in most cases, dysbiosis is not the sole cause of these conditions. It is only one component of the complex interaction between the microbiota, the immune system, genetics, and environmental factors.
Should "Dysbacteriosis" Be Treated?
Treatment should target not "dysbacteriosis" but the specific disease or condition responsible for the patient's symptoms.
For example, after a course of antibiotics, certain probiotic strains with proven efficacy may be recommended. In patients with irritable bowel syndrome, diet, lifestyle modifications, pharmacological therapy, and—when clinically indicated—specific probiotics may all play important roles.
For this reason, there is no universal treatment for "dysbacteriosis."
A Personalized Approach Is the Future of Microbiome Medicine
Modern gastroenterology is increasingly focused on personalized patient assessment. Physicians consider not only laboratory findings but also symptoms, coexisting diseases, dietary habits, lifestyle, and other factors that influence the microbiota.
This approach allows healthcare professionals to choose evidence-based treatment strategies rather than attempting to treat the abstract concept of "dysbacteriosis."
Conclusion
"Dysbacteriosis" is not an independent medical diagnosis. Modern science instead uses the concept of dysbiosis, which describes changes in the microbial ecosystem but is not itself a disease.
The primary goal of healthcare professionals is not to treat a laboratory result or a diagnostic label but to identify the underlying cause of the patient's symptoms and select therapy supported by high-quality scientific evidence. This principle forms the foundation of personalized microbiome medicine.
Recent References:
1. Hill C, Guarner F, Reid G, et al. The ISAPP consensus statement on the scope and appropriate use of the term probiotic. Nat Rev Gastroenterol Hepatol. 2014. DOI: 10.1038/nrgastro.2014.66
2. Sanders ME, Merenstein DJ, Reid G, et al. Probiotics and prebiotics in intestinal health and disease: from biology to the clinic. Nat Rev Gastroenterol Hepatol. 2019. DOI: 10.1038/s41575-019-0173-3
3. Lynch SV, Pedersen O. The Human Intestinal Microbiome in Health and Disease. N Engl J Med. 2016. DOI: 10.1056/NEJMra1600266
4. Integrative HMP Research Network Consortium. The Integrative Human Microbiome Project. Nature. 2019. DOI: 10.1038/s41586-019-1238-8
5. Kho ZY, Lal SK. The Human Gut Microbiome – A Potential Controller of Wellness and Disease. Front Microbiol. 2018. DOI: 10.3389/fmicb.2018.01835
