Evaluation of Interleukin 19 level in acne vulgaris patients

Introduction: Acne vulgaris is a disease that affects youth. The majority of patients present with various types of lesions, including papules, comedones, pustules


Introduction
Acne is a disease of the sebaceous unit that affects youth. Cases present with different variations of lesions, representing papules, comedones, pustules, and nodules [1].
Many criteria are present in the pathogenesis of acne, like increased keratinization of the follicles, abnormal follicular desquamation, high sebum secretion, proliferation of bacteria, inflammation, and a genetic role [2].
Acne is a disease that takes time to develop; it happens once the hair follicles are filled with dead cells and sebaceous secretion [3]. It may be presented as blackheads, whiteheads, papules, nodules, oily skin, and scars [4].
The inflammatory process occurs in both early and late stages, so inflammation has an important role in the presence of inflammatory and non-inflammatory areas [5]. Interleukin 19 is a cytokine produced by the epithelium in response to pro-inflammatory stimulation [5]. Specific criteria of IL-19 are that they can give positive feedback action to magnify themselves when they are activated, they will produce cytokines in a continuous manner, and they help in inflammation [5].
The purpose of the current study was to detect the level of interleukin 19 in serum in mild acne cases.

Subjects
In the current case-control prospective study, 40 cases with mild acne and 100 healthy subjects, taken from the Dermatology Outpatient Clinic, Faculty of Medicine, were recruited after taking informed consent from all subjects.

Inclusion Criteria
Acne patients range in age from 16 to 30 years.

Exclusion Criteria
Patients with acne taking systemic treatment in the last month and topical creams in the last two weeks or those with diseases correlated with higher IL-19 production in serum or tissue, such as psoriasis, atopic dermatitis, and asthma, were excluded.

Medical History
That included the collection of different characteristics of the study populations, including medical history, sex, age, occupation, marital status, residence, and special habits of medical importance. Also, the onset, course, and duration of the disease; past history, including systemic and dermatological disorders, previous medications; and previous operations, family history, including systemic and dermatological disorders were reported

Laboratory Methods
Three ml of blood were collected from each participant in plain tubes, where the serum was separated and used for estimation of the IL-19 concentration level.

IL-19 concentration level assay by ELISA
The human IL-19 ELISA Kit (Novus Biologicals, Centennial, CO, United States) was used.

Statistical analysis
Data were coded and entered using the statistical package SPSS version 22. Data were statistically described in terms of mean, and standard deviation, for quantitative data and frequencies (number of cases) and relative frequencies (percentages) for qualitative data. For comparing categorical data, the chi-square test was performed. The independent t-test was used to compare quantitative variables between the two groups, and analysis of variance (ANOVA) with multiple comparison post hoc tests were used when comparing IL-19 levels in different severity grades in acne patients [6].

Results
The present study was conducted on 100 healthy controls and 40 mild acne patients, matching age and sex, and the patients were taken from the dermatology clinic at Fayoum University from September 2018 to June 2019.
The subjects were divided into two groups, group (I) included one hundred healthy subjects, and group (II) included 40 patients with mild acne.
There was no statistically significant difference in age between the healthy group and the cases (P=0.15) ( Figure  1).   There was no statistically significant difference in sex between control and selected acne patients (P =0.08) (Figure 2). IL-19 level by ELISA Technique among study groups showed that the mean level of IL-19 among the control group was 276.22+61.68 while the mean level among the mild acne group was 453.14+93.38 with (P <0.001). There was a statistically significant increase in the mean level of IL-19 in mild acne patients compared to normal control subjects (P < 0.001) (Figure 3).

Discussion
Acne vulgaris is a a disease that occurs in youth. Cases of acne present with a wide variety of lesions representing papules, blackheads, whiteheads, nodules, and pustules [1].
The mechanism of acne includes increased sebaceous secretion, increased follicular keratinization, the proliferation of bacteria and follicular colonization, and an inflammatory process [3].
Interleukin 19 is a cytokine produced by the epithelium in response to proinflammatory stimulation [5]. The specific criterion of IL-19 is that they can give positive feedback actions that are amplified when they are activated. They will produce cytokines in a continuous manner and help in inflammation [5].
The purpose of this study was to detect the Interleukin-19 serum levels present within mild acne cases and compare them with those of normal subjects to detect possible action of Interleukin-19 in acne pathogenesis.
The present study included 40 patients with mild acne and 100 subjects free from disease, taken from Fayoum University, dermatology outpatients after obtaining informed consent. The study included 40 cases of mild acne and 100 normal subjects. There was a significant increase in interleukin-19 levels in mild acne cases in comparison to healthy subjects (P<0.001).
That agreed with what was observed by Mochtar et al., 2018, who observed the rise of interleukin-19 in severe cases in comparison to moderate cases (P<0.05) and also a rise in interleukin-19 serum levels in severe cases compared to mild acne cases (P<0.05) [5]. They found no statistical difference in the serum level of interleukin-19 in mild acne compared to moderate acne (P = 0.312).
Also, a study was done by Oka et al., 2017, on the relation between the Il-19 serum level to inflammatory skin diseases like atopy and cutaneous lymphoma. In patients with cutaneous T cell lymphoma and atopic dermatitis, there is a high level of interleukin 19 in tissue and serum, and the serum IL19 levels positively correlate with clinical disease markers [7]. In another study done by Witte et al., 2014, they said that IL-19 is highly produced in both lesional and healthy skin of psoriatic patients. Tissue IL-19 secretion is reflected by higher IL-19 levels in blood, and that is related to the severity of psoriasis [8]. In another study done by Lin et al., 2016, on the detection of serum interleukin 19 in SLE, they found the interleukin 19 level is high in SLE patients with ulceration in the oral cavity, blood, and protein in the urine, and lower levels in patients with discoid lesions [9].

Conclusion
The study suggested that there is a possible correlation between the serum level of interleukin 19 and acne vulgaris pathogenesis.

Ethical considerations:
The study took the acceptance by the Ethical committee of the Faculty of Medicine at Fayoum University. To get informed consent from subjects, after discussion of the study, the aim of the study, and they had the right not to participate.

Patient consent:
Approval and consent to participate: In-formed written consent from patients who were invited to participate in the research was obtained.
Funding: This research is not funded.

Conflicts of Interest:
All authors declare no conflict of interest.

Availability of data and materials:
The datasets used and/or analyzed during the current study are available from the corresponding author on reasonable request