Pain insensitivity in a child with a de novo interstitial deletion of the long arm of the chromosome 4: Case report / Insensibilidad al dolor en un niño con una deleción intersticial de novo del brazo largo del cromosoma 4

Terminal and interstitial deletions of the distal segment of the long arm of chromosome 4 (Cr4q del) are not common genetic disorders. The severity of the phenotype is correlated with the size of the deletion because small deletions have little clinical impact, whereas large deletions are usually associated with multiple congenital anomalies, postnatal growth failure, and moderate to severe intellectual disability. Alteration in pain tolerance has not been included among these features, also in case of large deletions. The purpose of this report is to document a case of a child affected by interstitial Cr4q del, expressing pain insensitivity as clinical feature not previously described. We also offer a discussion on genetic disorders featuring pain insensitivity/indifference. Case report. A Caucasian girl aged 12 came to our observation for a developmental delay with multiple congenital abnormalities and moderate intellectual disability (IQ 47). A de novo interstitial Cr4 del between band q31.3 and q32.2 (Cr4 del q31.3 to q32.2) was found. The child also expresses no evidence of pain perception to injures which normally evoke pain. Consequently, she is affected by severe disability caused by painless injuries and self-injurious behaviours, such as excessive self-rubbing and scratching. The neurological examination manifested high pain threshold with preserved tactile sensitivity. Conclusions. This is the first report of pain insensitivity in a patient with a specific genetic deletion involving the interstitial region of the distal long arm of Cr4. Moreover, this report could serve as a useful model to better understand mechanisms of pain perception and its modulation.

Early onset intellectual disability in chromosome 22q11.2 deletion syndrome / Inicio temprano de discapacidad intelectual en el Síndrome de deleción del cromosoma 22q11.2

Chromosome 22q11.2 deletion syndrome, or DiGeorge syndrome, or velocardiofacial syndrome, is one of the most common multiple anomaly syndromes in humans. This syndrome is commonly caused by a microdelection from chromosome 22 at band q11.2. Although this genetic disorder may reflect several clinical abnormalities and different degrees of organ commitment, the clinical features that have driven the greatest amount of attention are behavioral and developmental features, because individuals with 22q11.2 deletion syndrome have a 30-fold risk of developing schizophrenia. There are differing opinions about the cognitive development, and commonly a cognitive decline rather than an early onset intellectual disability has been observed. We report a case of 22q11.2 deletion syndrome with both early assessment of mild intellectual disabilities and tetralogy of Fallot as the only physic manifestation.

El síndrome del cromosoma 22q11.2, también conocido como supresión o síndrome de DiGeorge o síndrome velocardiofacial, es uno de los síndromes más comunes de anomalías múltiples en los seres humanos. Este síndrome es comúnmente causado por una microdeleción del cromosoma 22 en q11.2 banda. Aunque este trastorno genético muestra varias anomalías clínicas y diferentes grados de compromiso orgánico, las características clínicas que han atraído la mayor atención son el comportamiento y el desarrollo, porque las personas con síndrome de deleción 22q11.2 tienen un riesgo 30 veces mayor de desarrollar esquizofrenia. Hay diferentes opiniones sobre el desarrollo cognitivo, y comúnmente se se ha observado un deterioro cognitivo en lugar de un inicio temprano de discapacidad intelectual. Presentamos un caso de síndrome de deleción 22q11.2 tanto con la evaluación temprana de discapacidades intelectuales leves como con la tetralogía de Fallot como única manifestación física.