記住我
ORIGINAL ARTICLE
Year : 2022 | Volume
: 23
| Issue : 2 | Page : 116-122
Clinico-Epidemiological study of childhood vitiligo and its associations: A hospital-based cross-sectional study
Fatima Tuz Zahra, Syed Suhail Amin, Mohammad Adil, Fariz Sarshar, Prateek Pathak
Department of Dermatology, Jawaharlal Nehru Medical College, Aligarh Muslim University, Aligarh, Uttar Pradesh, India
Correspondence Address:
Dr. Fatima Tuz Zahra
502, Ohad Homes, Medical Road, Aligarh - 202 002, Uttar Pradesh
India
Source of Support: None, Conflict of Interest: None
CheckDOI: 10.4103/ijpd.ijpd_2_21
Background: Vitiligo is a chronic pigmentary disorder resulting in hypopigmentary areas which progressively become amelanotic. The onset of vitiligo in childhood leads to severe psychological trauma to both patients and their parents. Aim: The aim was to study the clinical profile of childhood vitiligo (<18 years) and its association with other autoimmune diseases. Materials and Methods: It was a cross-sectional study of 256 clinically diagnosed childhood vitiligo cases over a period of two years. Detailed history of disease onset, duration, progression, associated diseases, and family history was recorded after informed consent from parents/guardians. Assessment of vitiligo was done by Vitiligo Area Severity Index (VASI). Results: Of the total 256 patients, females (n = 149) outnumbered males (n = 107) with a mean age of 9.80 ± 4.59 years with a mean disease duration of 1.9 years. The most common morphological type was vitiligo vulgaris (48.8%), while the most common site of disease onset was face (30.5%). Positive family history was seen in 49 patients (19.1%) and Koebner phenomenon in 54 patients (21.1%). The mean VASI score was 1.64. Conclusion: Childhood vitiligo is more common in females with anemia present in significant number of cases. Premature canities is the most common cutaneous association. Thyroid dysfunction was seen in nonsegmental variant. Children with the positive family history of vitiligo had higher mean VASI than those with the negative family history (P = 0.002).
Keywords: Autoimmune association, childhood vitiligo, Vitiligo Area Severity Index
Vitiligo is a common acquired, idiopathic, heritable depigmenting disorder of the skin and/or mucous membrane known since ancient times. The term vitiligo is derived from the Latin word "vitelius" meaning vale, i.e., pale pink flesh of calf, or from the Latin word "vitium," meaning blemish.[1]
The exact etiology is unknown, but various theories have been suggested for the etiology of vitiligo.[2] Autoimmune/autoinflammatory theory, dysregulated innate and adaptive immune response, oxidative stress, antibodies to normal human melanocytes, melanocyte-specific cytotoxic T-cells, defective keratinocyte metabolism, defective tetrahydrobiopterin, and catecholamine biosynthesis.
Recently, it has been found that vitiligo pathogenesis is linked to pigment homeostasis.[3]
It occurs worldwide with an overall prevalence of 1%. However, its incidence ranges from 0.1% to >8.8% across the country and other parts of the world.[4] Very few studies of childhood vitiligo have been conducted in Uttar Pradesh (U. P.). This is the first attempt to study the clinical profile of childhood vitiligo and its association with other autoimmune diseases in western U. P.
Materials and MethodsStudy design
This was a cross-sectional study conducted from September 2017 to August 2019. A total of 256 clinically diagnosed cases of childhood vitiligo attending the Outpatient Department of Dermatology were recruited for the study. Clearance for the study was obtained from the Institutional Ethics Committee (IEC Acceptance: D. No. 1007/FM). Informed consent was taken by the patient's parents or guardians in a language understandable to them.
Sample size
The sample size was calculated to be 256. This was obtained considering the 20% prevalence of childhood vitiligo in patients attending the Dermatology Outpatient Department at 95% confidence interval and 5% absolute allowable error.
Study subjects
Vitiligo is defined by milky-white colored or depigmented macules of variable sizes and shapes with or without leukotrichia. Hence, all clinically diagnosed cases satisfying the characteristics of vitiligo in both sexes younger than 18 years were included in the study. Patients with other forms of hypopigmentary disorders such as pityriasis versicolor, pityriasis alba, albinism, and contact depigmentation were excluded.
Detailed clinical history of each patient was taken and recorded in the proforma designed for the study regarding the demographic data of patients (name, age, sex, education, and residence), age of onset, duration and progression, site of initial lesion, associated systemic and cutaneous problems, Koebner phenomenon, family history of vitiligo, and other autoimmune diseases.
General physical and systemic examination was performed. Complete cutaneous examination was done in all patients regarding distribution, symmetry, morphological pattern, presence of white hair, and perifollicular pigmentation.
Photographs of the cases were taken for documentation after taking consent from the parent/guardian. Wood's lamp examination was also done in few cases to support the diagnosis. Assessment of vitiligo was done by Vitiligo Area Severity Index (VASI).
Statistical analysis
All the data were compiled and tabulated in the Statistical Package for the Social Sciences version 25 (IBM Corp., Armonk, NY). Percentages, ranges, means, and standard deviations were used to describe the quantitative variables. The data were analyzed using tests such as Chi-squared tests, independent sample "t"-tests, and Pearson correlation tests. A two-tailed probability value of <0.05 was considered statistically significant
ResultsOut of the total 256 patients, females (n = 149, 58.2%) outnumbered males (n = 107, 41.8%). In our study, 6–9 years was the most common age group affected by vitiligo. The mean age was 9.80 ± 4.59 years, while the youngest patient was of 4 months. The most common age of onset was 3–9 years (51.6%). The mean age of disease onset was 7.88 ± 4.13 years. The duration of vitiligo varied from one month to 12 years with the mean duration of 1.9 years in our study. [Table 1].
Maximum number of patients had vitiligo for ≤6-month duration comprising 32% of total patients. The most common site of onset of vitiligo was face (30.5%) followed by lower limbs (26.6%). Vitiligo vulgaris (48.8%) was the most common clinical type [Table 2]. Multiple sites (41%) were involved in most of the patients of vitiligo. The common site of involvement was head and neck (27.3%) followed by lower limb (12.5%) and trunk (7.0%). History of intercurrent infection (9.4%) was the most common precipitating factor found followed by trauma (5.9%) and stress (2.7%), while no precipitating factor was present in 82% of cases of childhood vitiligo. Family history was positive in 49 patients (19.1%). First-degree relatives were the most commonly affected (9.8%) in our study [Figure 1]. Disease was progressive in 134 patients (52.4%), while stable vitiligo (static + regressive) was found in 122 patients comprising 47.6% of the total. Family history of diabetes was found in 7.4% of patients of childhood vitiligo followed by hypertension (5.5%) and thyroid disorder (5.1%). Koebner phenomenon was present in 54 patients (21.1%). Leukotrichia was present in 46 patients (18%), out of which it was most frequent in vitiligo vulgaris variant (63%). Perifollicular pigmentation was present in 41 (16%) childhood vitiligo cases. In our study, majority of the patients (93.3%) were of Fitzpatrick skin type 4. Associated cutaneous conditions were present in 9.4% of patients in our study [Table 3]. The mean VASI score was 1.64, and most of the patients (94.5%) had VASI score <4. The mean VASI score among those with the positive family history (48 patients) was 2.33. The mean VASI score of children with negative family history was calculated to be 1.55. The difference was statistically significant [Table 4].
Table 2: Morphological types and laboratory evaluation of childhood vitiligo
Table 4: Mean Vitiligo Area Severity Index score in relation to family historyAnemia was present in 30.1% of patients of childhood vitiligo, of which females constituted 34.2% of total 149 female patients and males were 24.3% of the total 107 male patients. Thyroid profile was altered in 5.1% of childhood vitiligo, out of which hypothyroidism was present in 4.7% of cases. ANA was positive in 10 patients comprising 3.9% of childhood vitiligo. The mean blood glucose levels in males and females were 94.37 and 94.70, respectively. None of the patients had deranged blood sugar levels.
DiscussionIn our study, most of the cases were in the age group of 6–9 years at the time of presentation which was found similar to that of western and South Indian studies.[5],[6] The mean age of presentation in our study was 9.8 years. This was consistent with the study done by Gupta[7] who reported a mean age of 8.45 years in his study.
Our study shows females (58.2%) predominance over males (41.8%) similar to various Indian studies.[8],[9],[10],[11] The female-to-male ratio in our study was 1.4:1 which is akin to the study done by Puri.[12] However, a study by Hu et al.[13] reported equal incidence in both genders. The higher occurrence of the disease in females can be due to the increased stigma of the cosmetic appearance in vitiligo among the parents of the girl child and thus seek medical help may be sought earlier.
In our study, the most common age of onset of vitiligo was 3–9 years. Several studies also suggest that this age group was most commonly affected.[5],[14],[15],[16],[17] The mean age of disease onset was found to be 7.88 years in our study which is in accordance with studies of Gandhi et al.[10] and Puri.[12] Similar results are observed in international studies in China[18] and Saudi Arabia.[19]
We found an overlap in the age at presentation and age of onset in our study which shows that the parents are conscious about the disease in their children and present to the hospital seeking early treatment. The mean duration of vitiligo in our study was 1.9 years which is in accordance with a study by Gupta.[7]
In our study, the most common site of onset of vitiligo was face and neck (43.4%) followed by lower limb (26.6%), trunk (13.3%), upper limb (11.3%), and genitals (2%). This is in agreement with the study conducted by Kayal et al.[17] in which the predominant initial site of vitiligo was head and neck (46.8%) followed by lower extremities (33.0%), trunk (12.8%), upper extremities (6.4%), and mucosa (0.9%). Face and lower limb were the most common sites of onset of vitiligo observed in studies of Jain et al.,[5] Habib,[9] and Puri.[12] The exact interpretation is difficult but exposed, and trauma prone sites may develop vitiligo in genetically predisposed individuals.
Vitiligo vulgaris is the most common pattern seen in many Indian and international studies [Table 5] and [Table 6]. The most common morphological pattern in our study was vitiligo vulgaris (48.8%) followed by focal (27.7%), segmental (14.5%), and mucosal and acrofacial (3.1%) each. Puri[12] reported similar results. However, a study conducted by Jaisankar et al.[24] reported segmental vitiligo as the second most frequent morphological pattern.
Vitiligo is sometimes preceded by some precipitating factors. In our study, history of intercurrent infection (9.4%) was the most common followed by trauma (5.9%) and stress (2.7%). Indian studies by Murugaiyan et al.[25] and Raju and Nagaraju[26] reported history of trauma prior to the onset of vitiligo in 6.25% and 6.6% of children, respectively. The higher occurrence of intercurrent infections in our study may be due to poor hygiene and low socioeconomic condition of the patients visiting our hospital. Another reason may be due to mother being biased toward correlating the occurrence of vitiligo with prior episode of illness of the child.
Family history was positive in 49 patients (19.1%), and first-degree relatives were the most commonly affected in our study which corroborated with a study of Kayal et al.[17] and Puri.[12] However, a study by Handa and Dogra[8] reported lower incidence of positive family history in 12% of children with the predominant involvement of second-degree relatives than the first. Lower incidence of positive family history was seen in a study by Lin et al.[18] – 13.55% and a study by Sheth et al.[11] – 14%, while it was higher in a study conducted in Saudi Arabia by Al-Jabri and Al-Raddadi[19] – 37% and in India by Agarwal et al.[27] – 24.3%. These variations are due to differences in racial and genetic factors combined with culture of consanguineous marriages.
Family history of other autoimmune diseases was present in 51 patients (19.9%) of our study, among which diabetes mellitus was present in 19 patients (7.4%). Kayal et al.[17] also reported that family history of diabetes was more common in childhood vitiligo (13.76%).
Koebner phenomenon was present in 21.1% of our cases which corroborated with various Indian studies.[6],[11],[21] Incidence of koebnerization was more frequent in vitiligo vulgaris followed by focal and segmental vitiligo in our study similar to that reported by Habib.[9]
Various studies report findings of leukotrichia varying from 3.7% to 37% commonly associated with vitiligo vulgaris variants.[8],[12],[25],[26] In our study, leukotrichia was present in 46 number of cases (18%) and was most frequently observed in vitiligo vulgaris followed by segmental and focal vitiligo.
Perifollicular pigmentation is a sign of repigmentation. It was observed in 16% of cases of our study. A study conducted by Raju and Nagaraju[26] and Gandhi et al.[10] found perifollicular pigmentation in 12.2% and 46% of patients, respectively. These observations have not been made in other studies.
Maximum patients (93.4%) in our study were of Fitzpatrick skin type 4 followed by skin type 3 (2.3%) and type 5 (4.3%). This is due to the predominance of Fitzpatrick type 4 in northern India. Ours is the first study to observe the distribution of vitiligo based on skin types in children.
In our study, vitiligo was associated with other cutaneous disorders in 24 patients (9.4%) [Figure 2], [Figure 3], [Figure 4]. Premature canities was present in four patients (1.6%) followed by halo nevi, alopecia areata, and atopic dermatitis in three patients each (1.2%). A similar study conducted by Habib[9] and Gandhi et al.[10] found the association of alopecia areata and halo nevus in 1.2%, which was consistent with our study. Association of atopic dermatitis with vitiligo can be explained due to the presence of predisposing genes such as thymic stromal lymphopoietin which is common to both atopy and vitiligo.[28]
Figure 4: Vitiligo vulgaris in two sisters showing the involvement of bilateral legs and handsMost of the vitiligo children in our study had VASI between 1 and 4, and the mean VASI score was 1.64. Kayal et al.[17] found that majority of the patients (93.5%) with childhood-onset vitiligo had VASI up to 10 and the mean VASI score was 4.05 ± 5.84. The lower score of VASI in our study is due to the lesser body surface area involvement in childhood vitiligo. A study conducted by Jain et al.[5] supports this explanation as 74.3% of childhood vitiligo patients showed <5% body surface area involvement.
Children with the positive family history of vitiligo had higher mean VASI than those with a negative family history (P = 0.002). We studied the relation between VASI and the familial association of vitiligo.
Anemia was present in 77 patients (30.1%) of childhood vitiligo. A recent study by Soni et al.[29] found anemia as the most common association of vitiligo in children seen in 22.41% of cases. The presence of anemia in large number of patients is due to the poor socioeconomic status of the patients visiting our hospital.
The association of thyroid dysfunction is usually seen in nonsegmental vitiligo in childhood.[30],[31] In our study, thyroid abnormalities were present in 13 patients (5.1%). A study by Cho et al.[21] reported thyroid disorders in 5.9% of patients, which was consistent with our study.
Antinuclear antibody was positive in 3.9% of our patients. A study by Garg et al.[32] on 200 vitiligo patients aged between 3 and 78 years reported antinuclear positivity in four patients (2%). None of our patients had blood sugar abnormality. This is in accordance with a study done by Kayal et al.[17] in which they found that none of the patients with childhood-onset vitiligo had diabetes in comparison to 4% of patients with diabetes in adult-onset vitiligo.
Our study has shown the detailed pattern of childhood vitiligo in western Uttar Pradesh. We found a significant association between higher mean VASI and positive family history of vitiligo.
Limitation
The sample size in our study was small. Also it was a single-center hospital based study so it is difficult to extrapolate the results for wider population.
ConclusionChildhood vitiligo is more common in females with anemia present in significant number of cases. Premature canities is the most common cutaneous association. Hence, any depigmented patch seen in children should be examined carefully and regularly followed up. Children with the positive family history of vitiligo had higher mean VASI than those with the negative family history.
Declaration of consent
The authors certify that they have obtained all appropriate consent forms, duly signed by the parent(s) of the patient. In the form the parent(s) has/have given his/her/their consent for the images and other clinical information of their child to be reported in the journal. The parents understand that the names and initials of their child will not be published and due efforts will be made to conceal their identity, but anonymity cannot be guaranteed.
Financial support and sponsorship
Nil.
Conflicts of interest
There are no conflicts of interest.
References
留言 (0)