|Year : 2015 | Volume
| Issue : 3 | Page : 173-175
Waardenburg syndrome type 2
Rohini P Gaikwad1, Samipa Mukherjee2, Abhijit Saha3, Poonam Naphade4
1 Department of Dermatology, M.I.M.E.R Medical College, Talegaon Dabhade, India
2 Department of Dermatology, Bangalore Medical College and Research Institute, Bangalore, Karnataka, India
3 Pediatric Dermatology Unit, Rita Skin Foundation, Salt Lake, Kolkata, West Bengal, India
4 Consultant Dermatologist, Pushp Clinic, Pune, Maharashtra, India
|Date of Web Publication||10-Jul-2015|
Department of Dermatology, Bangalore Medical College and Research Institute, Bengaluru . 560 002, Karnataka
Source of Support: Nil, Conflict of Interest: None declared.
Waardenburg syndrome is a rare disorder characterized by sensorineural deafness with pigmentary anomalies and defects of the neural crest cells transmitted in an autosomal dominant fashion. Depending on the deformities caused by the disease some patients may need a multi-disciplinary approach while some may not need any treatment. Based on associated characteristics found and variable mutations there are four types of the syndrome. Here, we report a case of an 11-year-old male child who was found to have this disorder when a school survey was conducted at the school for deaf and dumb. It was also noted that there was generalized follicular hyperkeratosis, which could be a co-incidental finding.
Keywords: Rare, sensorineural deafness, Waardenburg syndrome
|How to cite this article:|
Gaikwad RP, Mukherjee S, Saha A, Naphade P. Waardenburg syndrome type 2. Indian J Paediatr Dermatol 2015;16:173-5
| Introduction|| |
Waardenburg syndrome (WS) is a rare autosomal dominant disorder inherited syndrome first described by Dutch Ophthalmologist Petrus Johannes Waardenburg in 1951. It is a congenital ectodermal germ layer defect with variable phenotype expressivity consisting of six major characteristics: Dystopia canthorum, broad nasal root, hypoplasia of the medial eyebrows, heterochromia irides, white forelock and congenital deafness of the sensorineural type. Based on the clinical features, the syndrome was subsequently classified into four subtypes. The incidence varies between 1/42,000 in the normal population. WS type 2 is a heterogeneous group with approximately 15% cases showing mutations in the microphthalmia associated transcription factor (MITF). Hereby, we report a case of 10-year-old boy who was diagnosed as a case of WS type 2, while a survey and screening were conducted at a school for deaf and dumb children in western Maharashtra.
| Case report|| |
A 10-year-old child, second child of nonconsanguineous marriage, born of full term normal vaginal delivery without any antenatal complications presented with light colored eyes and a patch of white hair at the frontal area [Figure 1]. The child was also reported to be congenitally deaf with sensorineural hearing loss. There was no similar history in the parents or siblings. The developmental milestones were normal. The past medical history was insignificant.
Clinical examination revealed a white forelock with underlying depigmented macule extending on to the forehead [Figure 2]. There were multiple depigmented macules of varying sizes scattered on the body. The child also had a broad nasal root. Ocular examination showed sparse eyebrows medically and total heterochromia irides. Multiple tiny pinpoint hyperkeratotic papules were scattered all over the body [Figure 3]. There was no evidence of dystopia canthorum as confirmed by the ophthalmologist.
Systemic examination was within normal limits with no evidence of neuro-developmental delay.
An audiometry done at this stage showed changes suggestive of sensorineural deafness.
The diagnosis of WS type 2 was established based on the constellation of the classical clinical signs.
| Discussion|| |
Waardenburg syndrome is a nonprogressive auditory-pigmentary disorder inherited in an autosomal dominant fashion although sporadic cases have been reported. The syndrome has been divided into four clinical subtypes based on the clinical features type 1-4 with the most common being type 1 and 2.
- Type 1: Persons usually have a wide space between inner canthus. Hearing impairment occurs in 20% of cases
- Type 2: Persons without a wide space between inner canthus of their eye but have many other characteristics of WS are described in type 2
- Type 3 and 4 are less common. WS type 3 also known as Klein-WS is associated with limb abnormality. The bony anomalies associated with this condition include the syndactyly, hypoplasia of the musculoskeletal system, flexion contractures, fusion of the carpal bones, and winged scapulae. WS type 4 is known as Shah-WS (these patients have Hirschsprung disease).
The pathogenesis of this condition has been linked to a defect in the differentiation and migration of melanocytes.
As per the diagnostic criteria proposed by the Waardenburg consortium, a patient must have two major or one major plus two minor criteria to be diagnosed as WS type 1. The major criteria are sensorineural hearing loss, iris pigmentary abnormality (two eyes different color or iris bicolor or characteristic brilliant blue iris), hair hypopigmentation (white forelock or white hairs at other sites on the body), dystopia canthorum (lateral displacement of inner canthi) and the presence of a first-degree relative previously diagnosed with WS. The minor criteria are skin hypopigmentation (congenital leukoderma/white skin patches), medial eyebrow flare (synophrys), broad nasal root, hypoplasia of alae nasi, and premature graying of hairs (before age 30). WS type 2 has all features of WS1 except dystopia canthorum.
The genes identified for WS include PAX3, MITF, EDNRB and EDN3 with WS 1 and 3 showing mutation in PAX3, WS type 2 with a defect in MITF and WS type 4 showing defects in EDNRB, and EDN3.
Although there is no treatment for the condition an early recognition with a multi-disciplinary approach may help in improving the quality of life of the patient.
| Conclusion|| |
We report this classical case of type 2 WS in order to create awareness regarding the entity and to emphasize on the need of genetic counseling considering the autosomal dominant nature of the disease. However, the limitation is inability to predict the severity of affection in the further progenies. Cosmetic improvement of the depigmented lesions can be achieved using topical or laser therapy along with skin grafting which thereby helps to improve the quality of life of the patient.
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[Figure 1], [Figure 2], [Figure 3]