Neuropathology of 22q11 Deletion Syndrome in an Infant

• Published in: Pediatric and developmental pathology Vol. 17; no. 5; pp. 386 - 392
• Main Authors: Wu, Peter, Teot, Lisa, Murdoch, Geoffrey, Monaghan-Nichols, A. Paula, McFadden, Kathryn
• Format: Journal Article
• Language: English
• Published: Los Angeles, CA SAGE Publications 01-09-2014; SAGE PUBLICATIONS, INC
• Subjects: 22q11 Deletion Syndrome - diagnosis; 22q11 Deletion Syndrome - genetics; 22q11 Deletion Syndrome - pathology; Autopsy - methods; Brain - pathology; Chromosomes, Human, Pair 22; Genetic Predisposition to Disease; Humans; Infant; Male; Neurons - pathology; cortex; 22q11 deletion syndrome; velocardiofacial syndrome; interstitial neurons; neuropathology; subplate
• ISSN: 1093-5266; 1615-5742
• DOI: 10.2350/13-11-1399-CR.1

The 22q11 deletion syndrome (22q11DS) is the most common microdeletion syndrome in humans and one of the chromosomal conditions most associated with psychosis and autism spectrum disorder. To date, only 2 neuropathologic studies of 22q11DS have been reported. Findings included polymicrogyria, neuronal heterotopias, excess subcortical white-matter (interstitial) neurons, significant white-matter gliosis/hypomyelination, and microvasculopathy. Here, we report on a 3-month-old infant with documented 22q11DS, tetralogy of Fallot, and pulmonary atresia. The brain exhibited tortuous cerebral vessels and proportionately smaller occipital lobes. Histologic examination revealed cerebral white-matter pathology and subtle differences in cortical lamination, including an excess of interstitial white-matter neurons compared with a sample of age-matched controls. There was a 15% increase in DARPP-32+ medium spiny neurons in the anterior-superior caudate. In this first neuropathologic report of an infant with 22q11DS, the findings were similar to previously reported manifestations and are likely secondary to perfusion issues, developmental microvasculopathy, and abnormal frontal cortical development.