Related Experiment Videos
Hypomelanosis of Ito. Neurological complications in 34 cases
I Pascual-Castroviejo1, L López-Rodriguez, M de la Cruz Medina
1Paediatric Neurology Service, Hospital Infantil, La Paz, Madrid, Spain.
Insights
Hypomelanosis of Ito is a rare genetic disorder affecting Spanish children, often presenting with significant non-cutaneous abnormalities. This study highlights the high prevalence of neurological and developmental issues, including intellectual disability and seizures.
Area of Science:
- Genetics
- Neurology
- Dermatology
Background:
- Hypomelanosis of Ito is a rare neurocutaneous disorder characterized by hypopigmented skin lesions.
- The disorder's incidence is estimated at 1 per 1000 new patients in pediatric neurology services.
- A significant proportion of affected individuals exhibit non-cutaneous abnormalities.
Purpose of the Study:
- To characterize the clinical manifestations and associated disorders in a cohort of Spanish children with Hypomelanosis of Ito.
- To investigate the spectrum of neurological, developmental, and dermatological findings in this patient group.
Main Methods:
- Retrospective analysis of 34 Spanish children diagnosed with Hypomelanosis of Ito.
- Clinical evaluation including neurological assessment, developmental testing (IQ), and dermatological examination.
- Review of associated non-cutaneous abnormalities and inheritance patterns.
Main Results:
- 94% of patients presented with non-cutaneous abnormalities.
- Intellectual disability (IQ < 70) was observed in 64.7% of cases, with an additional 14.7% having borderline intelligence.
- Seizures occurred in 53% of patients, and 38% had additional skin alterations beyond hypopigmentation.
- Associated conditions included macrocephaly, microcephaly, congenital heart disease, and autistic behavior.
Conclusions:
- Hypomelanosis of Ito is frequently associated with significant neurological and developmental impairments in children.
- The wide range of associated anomalies underscores the systemic nature of the disorder.
- While some cases suggest autosomal dominant inheritance, the genetic basis remains complex and not fully elucidated.
Abstract:
We studied 34 Spanish children with hypomelanosis of Ito. This disease has an incidence of 1 per 1000 new patients consulting a paediatric neurological service, or 1 per 8000-10,000 unselected patients in a children's hospital. About 94% of our patients show noncutaneous abnormalities. Mental retardation (IQ below 70) was present in 64.7%; another 14.7% had an IQ between 70 and 90, usually associated with poor school performance. Four children exhibited autistic behaviour. Seizures of various types were present in 53% of cases. Other skin alterations in addition to the typical hypomelanosis were observed in 38% of our cases: café-au-lait spots, angiomatous nevi, nevus marmorata, nevus of Ota, Mongolian blue spot, heterochromia of the iris or hair, and other nonspecific pigmentations. Other associated disorders occur inconsistently and include macrocephaly, microcephaly, hémihypertrophy, kyphoscoliosis, coarse facial features, genital anomalies, inguinal hernia, congenital heart disease, hypertelorism, and abnormalities of the teeth, feet and eyes. Autosomal dominant inheritance is demonstrated in some but not all cases.