Hearing Loss in Children with 22q11.2 Deletion Syndrome.

OBJECTIVES: Hearing loss is considered common in children with 22q11.2 deletion syndrome (22q11.2DS), with a few prior studies reporting a 32%-78% prevalence; mild-moderate conductive hearing loss has been reported most commonly. Overall, however, there remains a paucity of data regarding the frequency, type, age, and progression of hearing loss in children with 22q11.2DS. METHODS: Retrospective chart review was completed, and data combined for two large 22q centers. Inclusion criteria were children with 22q11.2DS and a documented audiogram. Data extracted included a laboratory-confirmed chromosome 22q11.2 deletion; co-morbidities; results of all audiograms and radiologic temporal bone imaging; and otologic surgical procedures. RESULTS: One thousand seven hundred sixty-nine charts were reviewed; 775 met inclusion criteria. Of these, 563 (73%) children had at least one abnormal audiogram demonstrating hearing loss. A total of 2,536 audiograms were reviewed; 74% of these showed abnormal hearing in at least one ear. Most of the hearing loss was conductive (right ear 76%; left ear 69%) and mild severity. For the children with SNHL, 90% of all follow-up audiograms were stable without progression. Hearing loss was identified across all pediatric age ranges. Ear tube placement occurred in 39% of children. CONCLUSION: This study confirms the high incidence of hearing loss for children with 22q11.2DS at some point in their childhood. In our cohort, hearing loss occurred in 73% of children and was most often conductive and mild in severity. The results highlight the importance of otolaryngology and audiology involvement in managing children with 22q11.2DS for timely diagnosis and treatment of hearing loss. LEVEL OF EVIDENCE: 4 Laryngoscope, 2024.

IRF7 and UNC93B1 variants in an infant with recurrent herpes simplex virus infection.

Neonatal herpes simplex virus (HSV) infection is a devastating disease with substantial morbidity and mortality. The genetic basis of susceptibility to HSV in neonates remains undefined. We evaluated a male infant with neonatal skin/eye/mouth (SEM) HSV-1 disease, who had complete recovery after acyclovir but developed HSV-1 encephalitis at 1 year of age. An immune workup showed an anergic PBMC cytokine response to TLR3 stimulation but no other TLRs. Exome sequencing identified rare missense variants in IFN-regulatory factor 7 (IRF7) and UNC-93 homolog B1 (UNC93B1). PBMC single-cell RNA-Seq done during childhood revealed decreased expression of several innate immune genes and a repressed TLR3 pathway signature at baseline in several immune cell populations, including CD14 monocytes. Functional studies in fibroblasts and human leukemia monocytic THP1 cells showed that both variants individually suppressed TLR3-driven IRF3 transcriptional activity and the type I IFN response in vitro. Furthermore, fibroblasts expressing the IRF7 and UNC93B1 variants had higher intracellular viral titers with blunting of the type I IFN response upon HSV-1 challenge. This study reports an infant with recurrent HSV-1 disease complicated by encephalitis associated with deleterious variants in the IRF7 and UNC93B1 genes. Our results suggest that TLR3 pathway mutations may predispose neonates to recurrent, severe HSV.

Sleep profiles in children with 22q deletion syndrome: a study of 100 consecutive children seen in a multidisciplinary clinic.

STUDY OBJECTIVES: While previous studies have suggested a high prevalence of sleep disorders in children with 22q deletion syndrome (22qDS), they were limited by potential selection bias. In the current investigation, we assessed sleep characteristics in 100 consecutive children presenting to a 22qDS multidisciplinary clinic. METHODS: An observational retrospective case series of consecutive children presenting to 22qDS multidisciplinary clinic was performed. Children aged 2 to 17 years of age were included, and data were abstracted including sleep characteristics (sleep history, Childhood Sleep Habits Questionnaire [CSHQ], and free response questions), comorbid medical conditions, and demographics. RESULTS: Overall, 100 children were included in analysis, 85% of whom had scores on the CSHQ consistent with clinically meaningful sleep disorder. Sleep problems were common in all domains of the CSHQ, including daytime sleepiness (66%), sleep-onset delay (54%), parasomnias (52%), night wakings (52%), sleep-disordered breathing (49%), sleep duration (45%), bedtime resistance (38%), and sleep anxiety (33%). Overall CSHQ score was significantly associated with daytime behavioral problems and speech delay [F(2,97) = 10.4, P < .001, adjusted R2 = 0.16]. The most common interventions reported to be helpful for sleep by parents were behavioral (routine, bedtime story), environmental (light avoidance at night, calming music), and pharmacologic (melatonin, clonidine). CONCLUSIONS: These data confirm a high prevalence of sleep disorders in a large, unselected sample of children with 22qDS, and suggest an important relationship between sleep dysfunction and daytime behavioral challenges. Our findings highlight the potential role for multimodal treatment approaches including behavioral, environmental, and pharmacologic interventions. CITATION: Ingram DG, Raje N, Arganbright JM. Sleep profiles in children with 22q deletion syndrome: a study of 100 consecutive children seen in a multidisciplinary clinic. J Clin Sleep Med. 2023;19(1):27-34.

T Cell Transcriptome in Chromosome 22q11.2 Deletion Syndrome.

Phenotypic variations of chromosome 22q11.2 deletion syndrome (22qDS) have unclear explanations. T cell lymphopenia in 22qDS related to varying degrees of thymic hypoplasia contributes to the phenotypic heterogeneity. No phenotype correlation with genotype or deletion size is known for lymphopenia. We investigated gene expression in human T cells of participants with and without 22qDS and T cells of participants with 22qDS with low or normal T cells. Peripheral blood was collected from participants aged 5-8 y. Immune function was checked. RNA sequencing was completed on isolated T cells, and differential gene expression profiles of T cells between 22qDS and healthy control subjects were established. A total of 360 genes were differentially expressed (q < 0.05) between T cells of patients with 22qDS (n = 13) and healthy control subjects (n = 6) (log2 fold change range, -2.0747, 15.6724). We compared gene expression between participants with 22qDS with low (n = 7) and normal T cell counts (n = 6), finding 94 genes that were differentially expressed (q < 0.05) (log2 fold change range, -4.5445, 5.1297). Twenty-nine genes correlated with T cell counts and markers CD3, CD4, CD8, and CD45RA+CD4 (R ≥ 0.8). We found significantly differentially expressed genes in participants with 22qDS compared with healthy control subjects and in participants with 22qDS with low T cell counts compared with those with normal T cell counts. Several enriched pathways suggest a role of T cells in defective communication between T cells and the innate immune system in 22qDS. Among these, the liver X receptor/retinoid X receptor pathway was noted to show several differentially expressed genes affecting participants with 22qDS compared with healthy control subjects and more so those with low T cell counts than in those with normal T cell counts.

HEM1 deficiency disrupts mTORC2 and F-actin control in inherited immunodysregulatory disease.

Immunodeficiency often coincides with hyperactive immune disorders such as autoimmunity, lymphoproliferation, or atopy, but this coincidence is rarely understood on a molecular level. We describe five patients from four families with immunodeficiency coupled with atopy, lymphoproliferation, and cytokine overproduction harboring mutations in NCKAP1L, which encodes the hematopoietic-specific HEM1 protein. These mutations cause the loss of the HEM1 protein and the WAVE regulatory complex (WRC) or disrupt binding to the WRC regulator, Arf1, thereby impairing actin polymerization, synapse formation, and immune cell migration. Diminished cortical actin networks caused by WRC loss led to uncontrolled cytokine release and immune hyperresponsiveness. HEM1 loss also blocked mechanistic target of rapamycin complex 2 (mTORC2)-dependent AKT phosphorylation, T cell proliferation, and selected effector functions, leading to immunodeficiency. Thus, the evolutionarily conserved HEM1 protein simultaneously regulates filamentous actin (F-actin) and mTORC2 signaling to achieve equipoise in immune responses.

Diagnostic interpretation of genetic studies in patients with primary immunodeficiency diseases: A working group report of the Primary Immunodeficiency Diseases Committee of the American Academy of Allergy, Asthma & Immunology.

Genetic testing has become an integral component of the diagnostic evaluation of patients with suspected primary immunodeficiency diseases. Results of genetic testing can have a profound effect on clinical management decisions. Therefore clinical providers must demonstrate proficiency in interpreting genetic data. Because of the need for increased knowledge regarding this practice, the American Academy of Allergy, Asthma & Immunology Primary Immunodeficiency Diseases Committee established a work group that reviewed and summarized information concerning appropriate methods, tools, and resources for evaluating variants identified by genetic testing. Strengths and limitations of tests frequently ordered by clinicians were examined. Summary statements and tables were then developed to guide the interpretation process. Finally, the need for research and collaboration was emphasized. Greater understanding of these important concepts will improve the diagnosis and management of patients with suspected primary immunodeficiency diseases.

Immunoglobulin E as a Biomarker in Asthma.

Asthma is a chronic disease that affects children and adults with significant morbidity and mortality. It is multifactorial, with genetic and environmental factors affecting the overall course of the disease. Both specific and total immunoglobulin (Ig)E can be used in specific phenotypes such as allergic asthma. Using IgE as a biomarker for asthma provides a target for management and treatment. Biotherapeutics continue to emerge as important advances in asthma treatment, and their effect on IgE and its biomarker role continue to be studied.

Novel heterozygous pathogenic variants in CHUK in a patient with AEC-like phenotype, immune deficiencies and 1q21.1 microdeletion syndrome: a case report.

BACKGROUND: Ectodermal dysplasias (ED) are a group of diseases that affects the development or function of the teeth, hair, nails and exocrine and sebaceous glands. One type of ED, ankyloblepharon-ectodermal defects-cleft lip/palate syndrome (AEC or Hay-Wells syndrome), is an autosomal dominant disease characterized by the presence of skin erosions affecting the palms, soles and scalp. Other clinical manifestations include ankyloblepharon filiforme adnatum, cleft lip, cleft palate, craniofacial abnormalities and ectodermal defects such as sparse wiry hair, nail changes, dental changes, and subjective hypohydrosis. CASE PRESENTATION: We describe a patient presenting clinical features reminiscent of AEC syndrome in addition to recurrent infections suggestive of immune deficiency. Genetic testing for TP63, IRF6 and RIPK4 was negative. Microarray analysis revealed a 2 MB deletion on chromosome 1 (1q21.1q21.2). Clinical exome sequencing uncovered compound heterozygous variants in CHUK; a maternally-inherited frameshift variant (c.1365del, p.Arg457Aspfs*6) and a de novo missense variant (c.1388C > A, p.Thr463Lys) on the paternal allele. CONCLUSIONS: To our knowledge, this is the fourth family reported with CHUK-deficiency and the second patient with immune abnormalities. This is the first case of CHUK-deficiency with compound heterozygous pathogenic variants, including one variant that arose de novo. In comparison to cases found in the literature, this patient demonstrates a less severe phenotype than previously described.

Overview of Immunodeficiency Disorders.

The spectrum of primary immunodeficiency disorders (PIDs) is expanding. It includes typical disorders that primarily present with defective immunity as well as disorders that predominantly involve other systems and show few features of impaired immunity. The rapidly growing list of new immunodeficiency disorders and treatment modalities makes it imperative for providers to stay abreast of the latest and best management strategies. This article presents a brief overview of recent clinical advances in PIDs.

A patient with polymerase E1 deficiency (POLE1): clinical features and overlap with DNA breakage/instability syndromes.

BACKGROUND: Chromosome instability syndromes are a group of inherited conditions associated with chromosomal instability and breakage, often leading to immunodeficiency, growth retardation and increased risk of malignancy. CASE PRESENTATION: We performed exome sequencing on a girl with a suspected chromosome instability syndrome that manifested as growth retardation, microcephaly, developmental delay, dysmorphic features, poikiloderma, immune deficiency with pancytopenia, and myelodysplasia. She was homozygous for a previously reported splice variant, c.4444 + 3A > G in the POLE1 gene, which encodes the catalytic subunit of DNA polymerase E. CONCLUSION: This is the second family with POLE1-deficency, with the affected individual demonstrating a more severe phenotype than previously described.

Genetic variation within the histamine pathway among patients with asthma--a pilot study.

OBJECTIVE: Histamine is an important mediator in the pathophysiology of asthma. We have previously reported that HRH1 is differentially expressed among those with asthma compared to those without asthma. Single histamine-related genes have also been associated with asthma. We aimed to evaluate known single nucleotide polymorphisms (SNPs) in genes along the histamine biotransformation and response pathway, and determine their association with asthma and HRH1 mRNA expression. METHODS: We enrolled children and adults (n = 93) with/without asthma who met inclusion/exclusion criteria. Genotyping was performed for nine known SNPs in the HDC, HRH1, HRH4, HNMT and ABP1 genes. HRH1 mRNA expression was determined on RNA from buccal tissue. General linear model, Fisher's exact test and Chi-square test were used to determine differences in allele, genotype and haplotype frequency between subjects with and without asthma and differential HRH1 mRNA expression relative to genotype. Statistical significance was determined by p < 0.05. RESULTS: No difference was observed in genotype/allele frequency for the nine SNPs between subjects with and without asthma. The HNMT-1639C/-464C/314C/3'UTRA haplotype was more frequently observed in those without asthma than those with asthma (p = 0.03). We also observed genetic differences relative to race and gender. HNMT 314 genotype CT was more frequent in males with asthma compared to those without asthma (p = 0.04). CONCLUSIONS: Histamine pathway haplotype was associated with a diagnosis of asthma in our cohort but allele and genotype were not. Subgroup evaluations may also be important. Further studies are needed to determine the potential biological/clinical significance of our findings.

Utility of next generation sequencing in clinical primary immunodeficiencies.

Primary immunodeficiencies (PIDs) are a group of genetically heterogeneous disorders that present with very similar symptoms, complicating definitive diagnosis. More than 240 genes have hitherto been associated with PIDs, of which more than 30 have been identified in the last 3 years. Next generation sequencing (NGS) of genomes or exomes of informative families has played a central role in the discovery of novel PID genes. Furthermore, NGS has the potential to transform clinical molecular testing for established PIDs, allowing all PID differential diagnoses to be tested at once, leading to increased diagnostic yield, while decreasing both the time and cost of obtaining a molecular diagnosis. Given that treatment of PID varies by disease gene, early achievement of a molecular diagnosis is likely to enhance treatment decisions and improve patient outcomes.

Higher risk factor burden and worse outcomes in urban carotid endarterectomy patients.

BACKGROUND AND PURPOSE: Previous multicenter carotid endarterectomy (CEA) studies had screening criteria for patient comorbidities and very few blacks. We assessed the hypothesis that CEA results from two urban hospitals would approximate those of the previous multicenter trials. METHODS: A retrospective chart review was completed at two urban hospitals for CEA procedures done in 2003 and 2004. Demographic information and past medical history was recorded. In hospital perioperative complications (stroke or myocardial infarction [MI]) were noted. We calculated an expected perioperative stroke rate based on trial figures and our proportion of symptomatic and asymptomatic patients. RESULTS: Patients in our cohort had significantly higher rates of hypertension, diabetes, smoking, black race, and elderly status compared to previous trials. The expected perioperative stroke was 3.1%, and the observed stroke rate was 4.7% (P=0.36). Observed rates of MI (6.7%, P<0.001)) and stroke or MI (11.3%, P<0.0001) were higher than expected based on the previous trials. The stroke or MI rate in black subjects was higher (15.4% versus 5.6%, P=0.065) and this was significant at the hospital with lower CEA volume. CONCLUSIONS: In two urban hospitals, CEA results were significantly worse than previous trials. Patient selection is likely to play a role because our cohort had higher numbers of hypertensives, diabetics, smokers, blacks, and elderly patients. Clinicians need to carefully consider the risk/benefit ratio of CEA in urban patients because our study shows that these patients have a large number of medical comorbidities and worse outcomes after CEA.