There is a strong genetic component to eczema, but rising case numbers in recent decades suggest that external factors may also contribute to the development of eczema in significant ways.
Research suggests that approximately 1 in 5 children and more than 1 in 100 adults experience eczema, making it one of the most common skin conditions around the world. Eczema is particularly prevalent among younger children, with nearly half of all cases developing within the first year of life.
Eczema is a chronic inflammatory condition that results from a
Given the role of inflammation in eczema, factors that affect the development of the immune system in early childhood, including the use of antibiotics, have been of particular interest to experts.
In this article, we examine how antibiotics can affect the developing immune system and how this might influence a person’s risk of eczema in the future.
The microbiome is the collection of bacteria, viruses, and other microorganisms that live in and on the body. It includes bacteria in the gut, as well as those on the skin.
A well-balanced microbiome provides a variety of health benefits by:
- supporting digestion
- providing essential vitamins and amino acids
- preventing overgrowth of harmful microbes
- stimulating development of the immune system
The microbiome helps support immune development by training the immune system to distinguish the pathogenic microbes that can cause disease from the beneficial ones that support human health.
Disruption of the microbiome ecosystem, particularly early in life, can interrupt this training process and make it difficult for the immune system to recognize friend from foe.
Antibiotic use, for example, can disrupt essential interactions between the microbiome and the immune system by killing healthy bacteria in the gut and on the skin, resulting in the development of abnormal immune responses.
As a result, the immune system reacts to the normal microflora of the gut or skin, leading to chronic inflammation.
Given the inflammatory nature of eczema, many experts have wondered whether early antibiotic use may trigger the development of eczema, as well.
Overall, most studies suggest an association between antibiotic use and eczema. According to an analysis of 34 clinical studies spanning the last 6 decades, children who had exposure to antibiotics within the first 2 years of life were
A more recent study involving more than 700,000 children from Sweden reaffirmed these results. It found that children who had exposure to antibiotics in the womb or during the first year of life were
However, not all studies have seen the same association between eczema and antibiotic use, and others suggest that there may be more to the relationship.
For example, some studies suggest that the timing of antibiotic use may be important.
A 2019 review looked at seven different studies that examined antibiotic exposure during specific intervals throughout pregnancy. It found that although prenatal exposure did increase the likelihood of developing eczema, antibiotic use during the third trimester did not affect eczema risk.
Underlying genetics or familial factors likely play a role as well. Many studies that have identified a relationship between antibiotic use and eczema have found that this relationship becomes
These findings suggest that there may be one or more underlying factors that affect several family members and increase the likelihood of both eczema and infections that require antibiotics.
Therefore, an increased risk of eczema may not be a direct result of antibiotic use but the result of some other trigger that also increases the risk of infections.
Genetics are likely to play a role in moderating this dual effect. A recent study found that among nearly 600 children in China, those with a genetic mutation in an immune-related gene were over
If eczema is the result of the dysregulation of the gut microbiome, some experts have suggested that the use of probiotics may help control symptoms of eczema.
Additionally, in a randomized controlled trial of infants at high risk of developing eczema, the use of a probiotic during the first 6 months of life
Although current evidence suggests that probiotics are unlikely to affect a person’s risk of eczema, studies have not directly examined the use of probiotics after antibiotic use. Some research does suggest that probiotics
Probiotics are not a risk-free treatment, and it is best to consult a doctor before initiating their use, particularly for young children.
Eczema occurs as a result of a variety of internal and external factors that result in immune dysregulation and contribute to chronic inflammation.
Antibiotic use early in life may disrupt the development of the immune system and increase the likelihood of developing eczema. Other factors, such as genetics, likely modulate these effects as well.
If children who are already at increased risk of eczema or other allergic diseases have exposure to antibiotics, their parents or caregivers should talk with a doctor about how to reduce the risk of eczema developing.