Doctors discover genetic and viral causes of adenoid hypertrophy in kids

RUDN doctors have discovered genetic and viral causes of a frequent ENT disease in children – adenoid hypertrophy. The results are published in Life.

Adenoid hypertrophy (AH), or their overgrowth, is one of the most common ENT diseases in children. Consequences range from snoring and frequent runny nose to respiratory arrest in a dream. However, the causes of AH have not yet been identified. RUDN doctors found that adenoid hypertrophy can have a genetic and viral etiology.

“Adenoid tissue physiologically increases in children aged 2 to 12 years, but at the same time, excessive tissue growth can have a negative effect on the health of the child, including nasal breathing, nasal congestion, upper airway obstruction, snoring, sleep disturbance,” said Yulia Lomaeva, researcher at the Department of Otorhinolaryngology, RUDN University.

A total of 144 children took part in the study, of which 106 patients with adenoid hypertrophy constituted the comparison group and 38 patients without adenoid hypertrophy were assigned to the control group. The diagnosis of HA was established on the basis of complaints, anamnesis, ENT examination, as well as instrumental research methods (endoscopic examination of the nose and nasopharynx, radiography of the nasopharynx). Doctors examined the IL – 10 G -1082 A (rs 1800896) gene polymorphism, as well as a number of viruses obtained by taking a swab from the nasopharynx.

Herpes simplex virus type 6 ( HHV 6) and cytomegalovirus (CMV) were more common in patients with adenoid hypertrophy (HA). The HHV 6 virus turned out to be the most frequent -; 60% of children with GA were infected with it. The more severe the degree of adenoid enlargement, the more common are HHV 6 viruses and Epstein-Barr virus (EBV). For example, for the third, most difficult, degree of hypertrophy, the frequency of HHV 6 was almost 80%. From this, doctors concluded that there may be a connection between adenoid hypertrophy and HHV 6, CMV and EBV viruses.

The second important conclusion of the authors is the dependence of the disease on the genotype. The difference between patients with and without adenoid hypertrophy was found in the polymorphism of the IL – 10 gene. IL 10. If a combination of GG is in a certain position , then the chances that this person will have adenoid hypertrophy are less than with other alleles.

Adenoids are the first line of defense against bacteria and viruses. We hypothesize that the presence of HHV6 and CMV infections affects the development of adenoid hypertrophy, and that HHV6 and EBV may contribute to adenoid enlargement. The GG genotype of the IL-10 gene may play a role in protection against adenoid hypertrophy and enlargement of adenoid tissue to its maximum size. In the future, it is necessary to confirm our findings and, possibly, to discover the role of other genetic modifications. It is also necessary to evaluate the role of other herpesviruses.”

Valentin Popadyuk, MD, Head of the Department of Otorhinolaryngology, RUDN University