Relationship of herpesvirus (HSV1, EBV, CMV, HHV6) seropositivity with depressive disorder and its clinical aspects: The first study in children.

Infections can lead to the onset of mood disorders in adults, partly through inflammatory mechanisms. However pediatric data are lacking. The aim of this study is to evaluate the relationship between depressive disorder and seropositivity of herpes virus infections in children. The sample group consisted of patients diagnosed with depressive disorder according to DSM-5 diagnostic criteria and healthy volunteers, being between 11 and 18 years with clinically normal mental capacity. All children completed DSM-5-Level-2 Depression Scale, DSM-5-Level-2 Irritability Scale, DSM-5-Level-2 Sleep Scale, DSM-5-Level-2 Somatic Symptoms Scale. The levels of anti-HSV1-IgG, anti-CMV-IgG, anti-EBNA, and anti-HHV6-IgG were examined in all participants. Patients with an antibody value above the cut-off values specified in the test kits were evaluated as seropositive. The mean age was 15.54 ± 1.57 years in the depression group (DG), 14.87 ± 1.76 years in the healthy control group (CG). There were 4 boys (11.2%), 32 girls (88.8%) in the DG, 9 boys (21.9%) and 32 girls (78.04%) in the CG. There was no statistically significant difference between the groups in terms of the presence of seropositivity of HSV1, CMV, EBV, and HHV6. HHV6 antibody levels were significantly higher in the DG (p = 0.000). A significant positive correlation was found between HHV6 antibodies and DSM-5 level-2 somatic symptoms scale score. HHV6 antibody levels were found to be significantly higher in patients with existing suicidal ideation in the DG (n = 13) compared to those without existing suicidal ideation in the DG (p = 0.043). HHV6 persistent infections may be responsible for somatic symptoms and etiology of suicidal ideation in childhood depressive disorder.