Epidemiological and clinical profile of childhood vitiligo in Abidjan: a study of 40 cases
Célestin K. Ahogo, Isidore Kouassi Yao, Ulrich Nguena Feungue, Koffi Kouame Pâcome Gbandama, Somin Stéphanie Coulibaly, Ange-Sylvain Allou, Alexandra Dominique Ngangue Engome
Department of Dermatology and Infectiology, Training and Research Unit of Medical Sciences, Félix Houphouët Boigny University, Abidjan, Côte d’Ivoire
Correspondence Address:
Ulrich Nguena Feungue
Medical Doctor, Cocody-Blockhauss; Dermatology and Venerology Unit of University Teaching Hospital of Treichville. Postal code: 01 BP V3 Abidjan 01
Côte d’Ivoire
Source of Support: None, Conflict of Interest: None
CheckDOI: 10.4103/ejdv.ejdv_15_21
Background Vitiligo is an acquired and visible leucoderma that can lead to social stigmatization. The aim of this study was to establish the epidemiological and clinical profile of childhood vitiligo in Abidjan. In fact, very little data is available on this chronic child disease in sub-Saharan Africa, particularly in Côte d’Ivoire.
Methods We carried out a cross-sectional study at University Teaching Hospital of Treichville from June 2017 to June 2018. All children under 16 years old with vitiligo who meet our selection criteria were included. CSPRO 7.2 and SPSS 23 software were used for data analysis and the significance threshold was set at 0.05.
Results The prevalence of childhood vitiligo was 1.78%. Our series consisted of 19 boys and 21 girls (sex ratio M/F: 0.9). Children aged between 9 and 15 years old were the most affected (45%). The main family history were diabetes (37.5%), early canitis (30%) and vitiligo (17.5%). Atopic dermatitis was the main dermatosis associated with the childhood vitiligo (17.5%). The main clinical form of vitiligo was the non-segmental form (47.5%). The segmental and mixed forms had rates of 42.5% and 10% respectively. The vitiligo lesions were mainly located in sun-exposed areas (52.5%) and the segmental vitiligo significantly reached the face (P=0.04). Segmental vitiligo was also more common in children aged 0 to 3 years (P=0.03). The Koebner phenomenon was present in 5 children and was statistically associated with non-segmental vitiligo (P=0.04).
Conclusion The prevalence of vitiligo in our series was 1.78%. This pathology occurs mainly in older children. The main clinical form was the non-segmental form. The affection was most often located on the sun-exposed areas.
Keywords: Abidjan, childhood vitiligo, epidemio-clinical profile
Vitiligo is an acquired leukoderma, characterized by the occurrence of achromic macules on the skin and/or depigmentation of the hair due to selective loss of melanocytes [1],[2]. The actual etiology is not known. Genetic predisposition, autoimmune disorders, stress, and disturbances of melanocyte homeostasis may contribute to the occurrence of the disease: this is the convergent theory that is most accepted today [3]. The main clinical presentations are segmental vitiligo, nonsegmental vitiligo and undetermined vitiligo [4].
Worldwide, the prevalence of childhood vitiligo is between 0.0 and 2.16% [5]. In sub-Saharan Africa, there are very few studies on childhood vitiligo. Faye et al. [6] in Mali found a prevalence of 0.23% in a population of children under 15 years of age living in rural areas. In Côte d’Ivoire, according to Yoboue et al. [7], pigmentary disorders accounted for 9% of all dermatological consultations; however, this study did not focus on childhood vitiligo.
The absence of data on childhood vitiligo in our country led us to carry out the present study. This study aims to establish the epidemiological profile of childhood vitiligo in Abidjan.
Patients and methodsType of study
We carried out a descriptive, cross-sectional study from June 2017 to June 2018 (13 months) at the Dermatology Unit of the University Teaching Hospital of Treichville. This Dermatology Unit is the biggest dermatology center of Côte d’Ivoire.
Study population and sampling
All children under 16 years old with vitiligo diagnosed by a dermatologist, attending the Dermatology Unit of University Teaching Hospital of Treichville, were consecutively enrolled in our study. Before enrollment, we obtained informed consent from the parents.
Data were collected from the parents. The data collection form included sociodemographic variables (sex, age of the child, nationality, ethnicity, and place of residence), personal and family history of autoimmune diseases, thyroid diseases, atopic dermatitis, diabetes, vitiligo, and early-onset canitis. The duration of disease progression, age of onset, type of vitiligo, localization sites, number of patches, presence of Koebner’s phenomenon, halo nevus, or associated dermatosis were also investigated.
Statistical analysis
We recorded the data in CSPRO 7.2 [Census and Survey Processing System version 7.2. CSPro is developed and supported by the U.S. Census Bureau and ICF Macro, the organization that implements the Demographic and Health Surveys (DHS)] and then exported these to Statistical Package for the Social Sciences version 23 (SPSS 23.0) (Fabricant: IBM: Internationnal Buisness Machine corporation in New York State) for statistical analysis. Categorical variables were described as numbers and percentages and quantitative variables were described as medians and interquartile ranges. The χ2 and Fisher tests were used to compare proportions and the Mann–Whitney Wilcoxon U test was used to compare medians. The significance level was set at 5%.
Ethical considerations
Permission for this research was obtained from the Director of University teaching hospital of Treichville before the study, and verbal informed consent was also obtained from the parents or carers of the child. The consent of children older than 7 years of age was also obtained before inclusion in the study. Anonymity was maintained and the information obtained was used for scientific purposes only.
ResultsSociodemographic characteristics
During our study period, we examined 2245 children. The diagnosis of vitiligo was confirmed in 40 children (19 boys and 21 girls; sex ratio 0.9), yielding prevalence of childhood vitiligo of 1.78% at the hospital. The majority of children (62.5%) seen for vitiligo were aged between 9 and 15 years (62.5%) ([Figure 1]). The median age of the children at the time of consultation was 10 years (range: 5–15; extremes of 2 and 15 years). Vitiligo began after 3 years in 70% of the cases ([Figure 2]). The median age at onset of vitiligo was 7 years (range: 2.3–10 years; extremes: 1 month and 15 years). There was no statistically significant difference between the median age at onset in boys and girls (P=0.24). However, there was a significant difference between the median age at onset of the disease and the median age of consultation (P<0.001), that is, a significant delay in consultation. The personal medical history included atopic dermatitis (17.5%), diabetes (10%), and autoimmune disease (2.5%). In terms of family history, we found diabetes (37.5%), early-onset cancer (30%), vitiligo (17.5%), autoimmune diseases (7.5%), and dysthyroidism (5%).
Clinical aspects
Nonsegmental vitiligo was the predominant type of vitiligo in our series (47.5%), followed by segmental vitiligo (42.5%) and mixed vitiligo (10%) ([Figure 3]). The body-site distribution of lesions is reported in [Table 1]. Face (32.5%) and lower limbs (32.5%) were the main sites of involvement. For segmental vitiligo, the preferential involvement site was the face (10/18; 55.6%) ([Table 2]); there was a statistically significant association between segmental vitiligo and facial involvement [odds ratio=5.3 (1.3–22.5); P<0.05]. Segmental vitiligo was also more frequently found in children under 4 years of age (8/17; 47.1%). Furthermore, there was a significant association (P=0.03) between segmental vitiligo and this age group of less than 4 years of age. Nonsegmental vitiligo was preferentially located on the legs (8/23; 34.8%).
Figure 3 (3A) Non-segmental vitiligo in a 9 years old child (Photo library Pr Ahogo, February 2018, CHUT). (3B) Segmental vitiligo in a 13 years old child.In our participants, the median age at onset of segmental vitiligo and nonsegmental vitiligo was similar in both sexes (P=0.19). For nonsegmental vitiligo, most patients had three and four patches (10/19; 52.9%) ([Table 3]). The median number of vitiligo patches in patients with nonsegmental vitiligo was 3, with extremes of 1 and 20 patches. There was no statistically significant difference between the number of lesions in males versus females (P=0.65). Koebner’s phenomenon was observed in five (12.5%) patients in our study and was significantly found in nonsegmental vitiligo (P=0.04).
DiscussionIn our study of childhood vitiligo in the outpatient attending Dermatology Unit of the University Teaching Hospital of Treichville, we found a hospital prevalence of 1.78%. Our prevalence is in line with the worldwide prevalence of childhood vitiligo, which is generally low; it ranges between 0 and 2.16%, as reported in the recent meta-analysis by Krüger and Schallreuter [5]. However, our prevalence is different from that reported in Mali (0.23%) [6]. This difference in prevalence from that of Mali (neighboring country) is linked to the difference in our methodologies. Our study was carried out at a referral dermatology center (which receives patients from the capital but also patients referred from all over the country), whereas the Malian study was carried out in the community. The reference dermatology center usually receives more dermatology cases, which would increase the frequency of dermatological conditions.
No clear sex preference can be established for childhood vitiligo [8],[9]. Nevertheless, some studies show a female predominance [10],[11] like ours (sex ratio male/female: 0.9). This female predominance is considered to be due to a greater demand for cosmetics in girls because the aesthetic discomfort is greater in girls than in boys [11].
In our series, childhood vitiligo occurs mostly in those older than 4 years of age (28/40; 70%). More precisely, the first vitiligo lesions occurred before 4 years of age in 12 (30%) children, between 4 and 8 years of age in 10 (25%) children and between 9 and 15 years of age in 18 (45%) children. Indian and Chinese studies have reported disease onset at 3 years of age in 17% of children, between 4 and 8 years of age in 42–49% of children and from 9 years of age in 35–40% of children [9],[12]. This distribution is close to that in our series. Indeed, vitiligo in children rarely begins before the age of 4 years [13]; when it begins before the age of 4 years, the affected skin surface is larger and the risk of disease progression is greater [8]. Pathophysiologically, in addition to a genetic predisposition to vitiligo, there are environmental factors, in particular, all causes of skin abrasion such as burns, sunburn, repeated microtrauma, scratches, friction, and compression. There are also emotional factors such as stress. In genetically predisposed children, environmental and emotional factors are likely to occur with age; this would explain why vitiligo is more often found in older children than in younger children.
In our participants, there was a statistically significant difference (P<0.001) between the median age of onset of vitiligo lesions (median: 7 years; interquartile range: 2.3–10 years) and the median age of consultation (median: 10 years; interquartile range: 10–15 years). This suggests a delay in consultation for vitiligo lesions. This delay in specialist consultation may be due to the rarity of associated functional signs such as pain and pruritus. Furthermore, due to the low income in our developing countries, aesthetic discomfort might be considered as a non-priority problem and thus delay consultation.
In our study, 17.5% of children with vitiligo had a family history of vitiligo. This result is similar to that of Akrem et al. [14] in Tunisia, who found a family history in 17.8% of the patients. As in our study, Hu et al. [9] did not find a significant difference between the two sexes in the presence of a family history of vitiligo. The presence of a family history suggests a genetic predisposition to vitiligo. Evidence such as the finding of HLA-DR4 in black Americans and the presence of vitiligo in homozygous twins supports this theory [14].
In 52.5% of our participants, the vitiligo lesions were found at the cephalic end. Our results are similar to those of Cho et al. in Korea, Agarwal and colleagues in India and Nicolaidou et al. [13] in Greece, who also reported a cephalic involvement. Indeed, lesions involved the cephalic site in 31–59% of patients [13]. In Nigeria, Ayanlowo et al. [10] reported a higher frequency of lesions on the face and legs. Sunburn is one of the favorable environmental factors when there is genetic predisposition [15]; this could explain the predominance of lesions on sun-exposed areas. Further studies on sun protection in vitiligo could be carried out to evaluate its impact on the prevention and treatment of vitiligo. We found a positive association between segmental vitiligo and the age group of children under 4 years (P=0.03). This finding was also reported by Agarwal et al. [16]. Segmental vitiligo is more common in younger children [16],[17]. In children with nonsegmental vitiligo, the median number of vitiligo patches was 3, with extremes of 1 and 20 lesions. In nonsegmental vitiligo, lesions are most often multiple. It would be interesting to treat vitiligo in general and nonsegmental vitiligo in particular early to avoid an increase in the number of lesions.
ConclusionThe prevalence of childhood vitiligo in the outpatient dermatology center in Abidjan is 1.78%. The main personal and family histories reported were atopic dermatitis and diabetes, respectively. The vitiligo was mainly located on the sun-exposed areas and the main clinical form that was found was nonsegmental vitiligo.
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Conflicts of interest
There are no conflicts of interest.
References
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