ESPE Abstracts

Background: The etiology of infantile colic is unknown. Its timing overlaps with that of minipuberty. To the best of our knowledge, the relationship between these entities has not been investigated. In this study, we aimed to assess the relationship between minipuberty and infantile colic by measuring the levels of sex steroids in saliva among infants with and without infantile colic.

Methods: Saliva samples were collected from 15- to 60-day-old term infants (n=139) between 9 am and 5 pm. Group 1 included infants with infantile colic diagnosed according to the Rome IV criteria (n=68, male:31, female:37). Remaining healthy infants constituted Group 2 (n=71, male:37, female:34). The salivary levels of estradiol (Esal) in females and testosterone (Tsal) in males were studied in duplicate by using the ELISA method. Demographic features and findings of physical examination and laboratory studies were compared between the two groups. Correlation analyses were performed while controlling for the effects of significant associations.

Results: The median (25^th-75^th centile) age and birth week for all infants were 33 (29-43) days and 39 (38.1-40) weeks, respectively. The demographic features of the groups were similar except for a median of 5 days earlier birth in the girls in Group 1 (P<0.001). Tsal in males showed a negative correlation with age (rs=-0.622, P<0.001) while Esal showed a similar tendency (rs= -0.224, P=0.061). Tsal in males (Group 1, 73.35 pg/ml vs Group 2, 77.66 pg/ml, P=0.956) and Esal (Group 1, 3.91 pg/ml vs Group 2, 4.03 pg/ml, P=0.683) in females did not differ between the groups. However, only in Group 1, Esal and body mass index (BMI) standard deviation scores were positively correlated (rs= 0.393, P=0.016) and there was a significant correlation between the sampling time and Tsal (rs=0.469, P=0.009).

Conclusion: The levels of sex steroids in the saliva of subjects with infantile colic were not different from those of the control infants. On the other hand, only among subjects with infantile colic, salivary estradiol levels and BMI of females were significantly correlated. We also observed that the later the sampling was done in the day, the higher the salivary testosterone levels in males were. Therefore, our findings suggest the presence of a relationship between minipuberty and infantile colic.