Dear Director:

After reading the article by Gabriel Díaz et al., Characterization of Patients with a Diagnosis of Autoimmune Hepatitis in a Quaternary Care Hospital in Cali 2014-2020,¹ published in your journal, in which they expressed that the highest prevalence of autoimmune hepatitis is in the adult population in a way “similar to the literature,” I would like to make an observation. The article concludes the above without including the pediatric population in the study since the Materials and Methods section mentioned that “the study observational cohort included patients over 16 years of age.” Therefore, I want to contrast the article’s conclusion with the following research¹.

According to Marino in Hepatitis autoinmune: conceptos clave, autoimmune hepatitis affects all age groups and all ethnicities and behaves bimodally since it occurs in age ranges between 10 and 30 and between 40 and 60. It is subdivided into autoimmune hepatitis type I and autoimmune hepatitis type II. The predominance is both in childhood and adulthood in the female sex since in 71-95% of cases in adults, those affected are women, and in 60-76% of cases in children, those affected are girls².

Ramos et al. assert in their article that the disease manifests bimodally at the beginning: the first interval around adolescence and the second in the 70s. They report a prevalence of 0.0245% (245 per 1,000,000 inhabitants); the disease occurs predominantly in Caucasians and manifests after 40 years of age in 72% of cases. According to European guidelines for autoimmune hepatitis, it has a prevalence of 15 to 25 cases per 100,000 inhabitants in the West and four to five cases per 100,000 inhabitants in the East. Delgado J et al. state that the incidence in adults in the south of Israel is 0.67, with two cases per 100,000 inhabitants per year. The frequency of the male-female ratio has changed over time, such as in Japan, where the prevalence was 1:7 in 2004 and 1:4 in 2016, as well as in other recent studies, in which the prevalence went from 1:9-1:10 to 1:4-1:6³.

Additionally, Katsumi et al., in their study Epidemiology and surveillance of autoimmune hepatitis in Asia, remark that in East Asia, patients with autoimmune hepatitis mostly manifest type 1. Meanwhile, autoimmune hepatitis type 2 is rare, and autoimmune hepatitis type 2 in South Asia is as common as in Europe and the United States. The HLA-DR4 serotype is associated with features of autoimmune hepatitis type 1 in East Asia, while the HLA-DR3 serotype is present in patients with autoimmune hepatitis in South Asia. An increase in the prevalence of autoimmune hepatitis worldwide was also mentioned: many studies have reported a prevalence of 19.44, 22.80, and 12.99 per 100,000 people in Europe, the United States, and Asia, respectively⁴.

Tanaka, in Autoimmune hepatitis: 2019 update, reveals that recent epidemiological studies indicated that the prevalence in both sexes, although mainly in men, is increasing worldwide⁵.

Thus, after reviewing the literature, it must be concluded that studies must include the pediatric population to achieve adequate epidemiological screening and express an opinion on the prevalent age groups. Although autoimmune hepatitis is more prevalent in women and adults, the pediatric population should not be ignored in order to reduce underdiagnosis.