Phenotypes Associated with 16p11.2 Copy Number Gains and Losses at a Single Institution.

Chromosome 16p11.2 is one of the susceptible sites for recurrent copy number variations (CNVs) due to flanking near-identical segmental duplications. Five segmental duplications, named breakpoints 1 to 5 (BP1-BP5), have been defined as recombination hotspots within 16p11.2. Common CNVs on 16p11.2 include a proximal ~593 kb between BP4 and BP5, and a distal ~220 kb between BP2 and BP3. We performed a search for patients carrying 16p11.2 CNVs, as detected using chromosome microarray (CMA), in the Molecular Diagnostic Laboratory at the University of Texas Medical Branch (UTMB), in Galveston. From March 2013 through April 2018, a total of 1200 CMA results were generated for germline testing, and 14 patients tested positive for 16p11.2 CNVs, of whom 7 had proximal deletion, 2 had distal deletion, 4 had proximal duplication, and 1 had distal duplication. Herein, we provide detailed phenotype data for these patients. Our study results show that developmental delay, abnormal body weight, behavioral problems, and hypotonia are common phenotypes associated with 16p11.2 CNVs.

Genotypic and phenotypic variability of 22q11.2 microduplications: An institutional experience.

Duplications in the 22q11.2 region can cause 22q11.2 duplication syndrome and encompass a variety of phenotypes including developmental delays, facial abnormalities, cardiovascular defects, central nervous system delays, and other congenital abnormalities. However, the contribution of these contiguous duplicated regions to the clinical phenotypes has not been fully elucidated. In this study, we identified nine patients carrying different 22q11.2 microduplications detected by chromosomal microarray. Of these patients, seven pediatric patients presented with various clinical features including two neonate cases died shortly after birth, and two healthy adults. We examined region specific genotype-phenotype associations and found unpredictability associated with 22q11.2 duplications in these nine patients.

Pediatric acute transverse myelitis overview and differential diagnosis.

Acute transverse myelitis is a clinical syndrome affecting the spinal cord, which is characterized by acute onset of motor, sensory, and autonomic dysfunction. Approximately 20% of cases of acute transverse myelitis occur in children. This review summarizes the current published literature on acute transverse myelitis, including epidemiology, diagnostic criteria, pathogenesis, clinical presentation, clinical evaluation, and differential diagnosis. The article also summarizes the neuroimaging features, acute and chronic complications, treatments, and prognosis of acute transverse myelitis in the pediatric population. The initial evaluation centers on differentiation from other causes of myelopathy, and cases are further divided into idiopathic or disease-associated acute transverse myelitis. Correct diagnosis is important for treatment and prognosis. Treatment begins with intensive surveillance for acute life-threatening respiratory or autonomic complications. Immunomodulating therapy is recommended for noninfectious causes, using high-dose intravenous corticosteroids or plasma exchange. Other therapeutic options are also discussed. Prognosis depends on a number of factors, and evidence suggests that the majority of children have a good outcome. A small percentage of children diagnosed with acute transverse myelitis later are diagnosed with other demyelinating diseases, especially neuromyelitis optica, or multiple sclerosis. The most common long-term complications of acute transverse myelitis are urinary, motor, or sensory dysfunction.