Do you understand the "multi-tasking" macrolides?

*The professional part involved in this article is only for reference by medical professionals.
We are all familiar with macrolide drugs.
They are a kind of antibacterial drugs commonly used in pediatrics to prevent infection by atypical pathogens.
However, this Class drugs, in addition to their job is "antibacterial", they also "multiple jobs"! Antibacterial is its job.
Macrolide drugs have good antibacterial effects against Haemophilus influenzae, Legionella pneumophila, Streptococcus pneumoniae, pertussis, mycoplasma, chlamydia, etc.
, especially against Mycoplasma pneumoniae, Chlamydia and avian Mycobacterial disease has a definite effect and can be used for infectious diseases such as community-acquired pneumonia, whooping cough, sinusitis, and otitis media.

Common drugs such as 14-membered ring macrolide clarithromycin, roxithromycin, 15 membered ring macrolide azithromycin, etc.
, their usage and dosage are not described here.

Antiviral such as azithromycin has an antiviral effect and inhibits the release of inflammatory factors, thereby achieving the effect of reducing airway inflammation.

Take infant bronchiolitis as an example.
The disease usually occurs in infants aged 2-6 months.
It is a wheezing lower respiratory tract disease.
The pathogens are mainly viruses such as respiratory syncytial virus and rhinovirus.
In the early stage of infection, the use of azithromycin can reduce The child’s condition is at risk of becoming severely ill.

Anti-inflammatory and immunomodulatory macrolide drugs affect the production of pro-inflammatory cytokines and chemokines by inhibiting the activity of nuclear transcription factors, and can hinder the adhesion and aggregation of neutrophils, regulate their apoptosis, and interfere with hypertrophy Physiological processes such as degranulation of cells play an anti-inflammatory and immune regulatory role.

In the use of pediatric asthma, a small dose of azithromycin can inhibit the concentration of Th2 cells and improve airway remodeling.
Moreover, because the release of neutrophils and arachidonic acid is not regulated by hormones, it is useful for refractory asthma.
(Only refers to children with non-eosinophilic asthma).

In the case of standard anti-asthma treatment, the addition of low-dose azithromycin can greatly improve the quality of life of children with refractory asthma.

In addition, in acute asthma attacks and refractory asthma cases, the detection rate of Mycoplasma pneumoniae is higher than that of normal children.
If such children are combined with Mycoplasma pneumoniae infection, the early combined use of azithromycin is beneficial to the recovery of the children's condition.

Reducing airway mucus secretion After airway infection, a large amount of mucus will be produced, which will not only lead to aggravation of small airway blockage, but also affect the efficacy of drugs to remove pathogens.

Macrolides can inhibit the overexpression of mucin 5AC, regulate intracellular signal transduction, and inhibit mucus production.

In cases of cystic fibrosis, there is a large amount of mucus in the airway of the child, which is difficult to remove, leading to repeated respiratory infections and irreversible lung injury.

The use of macrolide antibiotics (such as azithromycin, 22-30mg/kg per week, 6-12 months of treatment) can inhibit pro-inflammatory factors, reduce mucus secretion, and improve the lung function of children.

The synthetic biofilm that inhibits the biofilm makes the bacteria resistant to drug resistance and immune evasion, which affects the efficacy of antibacterial drugs and prolongs the course of the disease.

Macrolide drugs (especially clarithromycin) can inhibit the synthesis of bacterial biofilm and remove the biofilm that has been formed.

Scholars believe that biofilm may be an important factor in the occurrence and persistence of inflammation in recurrent and refractory chronic rhinosinusitis (CRS).
Clearing the biofilm can increase the rate of CRS symptom improvement and avoid endoscopic sinus surgery.

According to foreign reports, the improvement rate of macrolides on the symptoms of patients with chronic rhinosinusitis is 60% to 80%, and the efficacy of CRS without nasal polyps is significantly better than CRS with nasal polyps.

For CRS without nasal polyps, no eosinophilia, normal IgE, negative allergen test, and poor efficacy of conventional drug treatment, a small dose (half the conventional dose) of macrolide drugs is recommended (recommended Clarithromycin) is taken orally for a long time, and the course of treatment is not shorter than 12 weeks.

However, there are still few studies on children's CRS.

Treatment of gastroparesis.
Gastroparesis in children often manifests as nausea, vomiting, abdominal distension and abdominal pain, mostly idiopathic.

Macrolides (such as azithromycin) are actually motilin receptor agonists and can be used for the treatment of gastroparesis, but their efficacy and safety need to be studied.

Unexpectedly, the anti-infective macrolides are so powerful! In the process of use, we should also be alert to its adverse reactions: First: infantile hypertrophic pyloric stenosis.

Neonates within 14 days of age use macrolides to fight infections, and their risk of hypertrophic pyloric stenosis increases by 8 times.

Second: the risk of asthma.

The use of antibiotics (especially macrolides) in children within one year of age is positively correlated with asthma in children in later stages.

Third: the destruction of intestinal flora and the risk of obesity.

References: [1] Expert consensus on the antibacterial effects and clinical application of macrolides, Chinese Journal of Internal Medicine, 2017,56(7): 546-557 [2] Tang Xifeng, Clinical application and drug resistance of azithromycin And adverse reactions[J].
International Journal of Pediatrics,2021,48(2):104-107