Antibody deficiency and autoimmunity in 22q11.2 deletion syndrome.

BACKGROUND: Although severe T cell immunodeficiency in DiGeorge anomaly is rare, previous studies of humoral function in these patients have found no antibody abnormalities but have not examined the response to polysaccharide antigens. Isolated cases of autoimmunity have been reported. Several patients with 22q11.2 deletion attending our immunology clinic suffered recurrent sinopulmonary infection or autoimmune phenomena. AIMS: To investigate humoral immunodeficiency, particularly pneumococcal polysaccharide antibody deficiency, and autoimmune phenomena in a cohort of patients with 22q11.2 deletion. METHODS: A history of severe or recurrent infection and autoimmune symptoms were noted. Lymphocyte subsets, immunoglobulins, IgG subclasses, specific vaccine antibodies, and autoantibodies were measured. Subjects were vaccinated with appropriate antigens as indicated. RESULTS: Of 32 patients identified, 26 (81%) had severe or recurrent infection, of which 13 (50%) had abnormal serum immunoglobulin measurements and 11/20 >/=4 years old (55%) had an abnormal response to pneumococcal polysaccharide. Ten of 30 patients (33%) had autoimmune phenomena; six (20%) were symptomatic. CONCLUSIONS: Humoral immunodeficiency is more common than previously recognised in patients with 22q11.2 deletion. Normal T cell function and immunoglobulin levels do not exclude poor specific antibody responses. Patients should be referred for formal immunological assessment of cellular and humoral immune function.     

Immunologic features of chromosome 22q11.2 deletion syndrome (DiGeorge syndrome/velocardiofacial syndrome).

OBJECTIVES: To characterize immunologic function and clinical characteristics in patients with chromosome 22q11.2 deletion syndrome and determine whether there was significant change over time. METHODS: This study characterized the laboratory and clinical features of the immunodeficiency in a cohort of 195 patients with chromosome 22q11.2 deletion syndrome and used cross-sectional and analysis of variance to compare the findings in different age groups with control patients. Changes over time were also characterized by a model effect method in a subset of patients who were studied serially. RESULTS: Diminished T cell counts in the peripheral blood are common in patients with chromosome 22q11.2 deletion syndrome. The pattern of changes seen with aging in normal control patients was also seen in patients with chromosome 22q11.2 deletion syndrome, although the decline in T cells was blunted. Autoimmune disease was seen in most age groups, although the types of disorders varied according to age. Infections were also common in older patients, though they were seldom life threatening. CONCLUSIONS: Slow declines in T cell populations are seen in chromosome 22q11.2 deletion syndrome. Clinical manifestations of immunodeficiency, such as recurrent infection and autoimmune disease, were common in this population but had little relationship to specific immunologic laboratory features.     

Humoral immune responses and CD27+ B cells in children with DiGeorge syndrome (22q11.2 deletion syndrome)

The spectrum of T-cell abnormalities in 22q11.2 syndrome is quite broad, ranging from profound and life threatening to non-existent defects. Humoral abnormalities have been described in some of these patients, although no data are currently available on their phenotypical and functional B cell subsets. The purpose of this study was to investigate humoral immune function in a cohort of 13 children with DiGeorge syndrome by immunophenotyping B and by analysing their functionality in vivo. Humoral immunity was assessed by serum immunoglobulin evaluation, IgG subclasses determination, and testing of specific antibody titers to recall antigens. B cells were analyzed by flow cytometry and the relevant percentage of membrane surface expression of CD27, IgM, IgD was evaluated. In our cohort, one of 13 children (7.7%) had a complete IgA deficiency, four of 13 (30.7%) had minor immunoglobulin abnormalities, and five (38%) had an impaired production of specific antibodies. Five of 13 children (38%) had recurrent infections. Interestingly, peripheral CD27+ B cells were reduced in our patients as compared with age-matched healthy controls, and this decrement was statistically significant for IgM+ IgD+ CD27+ B cells. Immunoglobulin abnormalities were associated with the occurrence of recurrent infections. We conclude that a significant proportion of patients with DiGeorge syndrome have defective humoral immunity, which may represent an additional pathogenic mechanism underlying the increased susceptibility to infections. Whether the decreased CD27+ B-cell subset might be one of the defects that contribute to impaired humoral immunity, and to susceptibility to infection remains to be elucidated.     

Role of immunoglobulin subclasses and specific antibody determinations in the evaluation of recurrent infection in children.

We studied humoral immune function in 267 children with recurrent respiratory infections referred to our immunology clinic to determine the most appropriate immunologic studies for evaluating recurrent infections in children. Of this highly selected population, 58% had a partial deficiency in one or more of the major immunoglobulin isotypes or IgG subclasses (defined as at least 2 SD below the normal age-adjusted mean). In none of the patients was there a total absence of an immunoglobulin isotype. The most common abnormality was partial IgA deficiency, which was found in one third of the patients. Twenty-six patients had only partial IgG subclass deficiencies, of which 20 were deficiencies of a single subclass. IgG1 was an isolated partial defect in three patients, IgG3 in five patients, and IgG2 and IgG4 were selective partial defects in six patients each. Tetanus toxoid and pneumopolysaccharide type 3 were the most immunogenic of the immunogens tested; hyporesponsiveness to pneumococcal polysaccharide types 7, 9, and 14 was common. Nineteen percent of the patients with normal immunoglobulin concentrations who were tested had lower-than-expected antibody titers; 42% of those tested with partial isotype deficiencies had deficient antibody responses. Of 25 patients with selective partial IgG subclass deficiencies or combined IgG subclass deficiencies, eight had antibody deficiencies. Our findings indicate that a high proportion of children referred to immunology clinics for recurrent infection have a demonstrable immunologic abnormality. Selective IgG subclass deficiency or a combined IgG subclass deficiency without an associated deficiency in a major immunoglobulin isotype is unusual. Identification of such patients is not predictive of the capacity to form antibodies to the antigens tested in this study and, in our opinion, adds little to the initial evaluation of immune function in such children.     

FISH investigation of 22q11.2 deletion in patients with immunodeficiency and/or cardiac abnormalities

DiGeorge anomaly/velocardiofacial syndrome (DG/VCFS), called 22q11.2 deletion syndrome in general, is the most common chromosomal deletion syndrome found in humans. Typical facial features, palatal defects, conotruncal abnormalities of the heart, aplasia/hypoplasia of the parathyroid glands and of thymus are characteristics of this syndrome. Deletions of chromosome 22q11.2 (del22q11.2) are the leading causes of DG7VCFS. We report on a systematic search by fluorescence in situ hybridization (FISH) for deletions of chromosomes 22q11.2 in patients with a clinical suspicion or diagnosis of DG/VCFS. Using FISH we studied a series of 43 patients with suspected DG/VCFS. In this study, a total of 43 patients were investigated for the presence of a 22q11.2 deletion over a two-year period. Del22q11.2 was detected in 5 of the 43 patients tested. All patients with deletion had hypocalcemia, 80% had cardiac defects, 40% had facial dysmorphism, 40% had immunodeficiency , and 20% had otolaryngeal abnormalities. Chromosome 22q11.2 deletion is a relatively common condition and is readily diagnosed by FISH. We suggest that FISH analysis of 22q11.2 deletion should be performed in the presence of combined of hypocalcemia and congenital cardiac malformations, with or without any characteristics of the disease. This may facilitate an early diagnosis in such patients.     

Deficiency of IgG4 in children: association of isolated IgG4 deficiency with recurrent respiratory tract infection.

To study the relationship between serum IgG subclass deficiency and clinical host defense impairment, we reviewed the clinical and immunologic features of 123 patients with a history of recurrent infection who had been examined for immunodeficiency in our laboratory (group 1). We then compared immunoglobulin isotype levels with those in sera from 127 age-matched control subjects without recurrent infection from whom blood had been drawn for evaluation of atopy (group 2). There was a significantly higher prevalence of IgG4 deficiencies among patients with recurrent infections (17% vs 7%; p less than 0.02), solely because of a higher prevalence of isolated IgG4 deficiency (n = 9; 7.3%) than in atopic control subjects (n = 1; 0.8%; p less than 0.05); there was a comparable prevalence of multiple isotype deficiencies that included low levels of IgG4 (9.8% and 6.3%, respectively). All nine group 1 patients with isolated IgG4 deficiency had severe recurrent respiratory tract infections requiring multiple hospitalizations; in addition, five were atopic, five had asthma, and one had chronic diahrrea. Antibody responses to bacterial polysaccharide antigens were normal for age in all patients with isolated IgG4 deficiency; two had defective antibody responses to protein antigens. Isolated IgG4 deficiency appears to be associated with impaired respiratory tract defenses and may occur in the absence of an easily definable antibody deficiency state. This association suggests a physiologic defense role for mucosal IgG4.     

Immunological evaluation of allergic respiratory children with recurrent sinusitis

The objective of this study was to evaluate humoral immunity of allergic respiratory children with chronic/recurrent sinusitis. Twenty-seven allergic respiratory (persistent mild/moderate asthma and persistent allergic rhinitis) children (7-15-year old) with chronic or recurrent sinusitis were evaluated. Patients had symptoms and abnormal computer tomography scan even after two adequate treatments (long-lasting antibiotics, decongestants, and short-term oral corticosteroids). clinical examination, sweat test, total blood cell count, measurement of serum levels of: total and specific IgE, immunoglobulins (G, M, A), IgG subclasses, antibodies to Haemophilus influenza type b (IgG anti-Ps Hib) and pneumococcal serotypes (IgG anti-Ps 1, 3, 5, 6B, 9V, and 14) before and after active immunization (Act-Hib and Pneumo23, Aventis Pasteur SA, Lyon, France), Rubella neutralizing antibody titers and human immunodeficiency virus antibodies. Specific IgE to inhalant allergens higher than class III were observed in 24/27 patients. One patient had IgA plus IgG2 deficiency and other an IgG3 deficiency. Eight and 12 of 27 patients had IgG2 and IgG3 serum levels below 2.5th percentile, respectively. Immunological responses to protein and polysaccharide antigens were normal in all patients. Although our patients have been appropriately treated of their allergic diseases, they persisted with chronic/recurrent sinusitis and 60% of them had a documented osteomeatal complex blockade. In spite of the diagnosis of IgA plus IgG2 deficiency and an isolated IgG3 deficiency, in all patients an adequate response to Ps antigens was observed. Primary and/or secondary humoral immunodeficiency seems not to be the main cause of chronic/recurrent sinusitis in patients with respiratory allergic disease.     

IgG subclass specific antibody response in recurrent bronchitis.

The IgG subclass specific immune response against pneumococcal type 3 polysaccharide antigen before and after immunisation in healthy children and children with recurrent bronchitis was studied. Recurrent bronchitis was defined as three or more episodes a year, during at least two consecutive years, of bronchopulmonary infection, productive cough with or without fever, and/or diffuse rales by physical examination. Twenty five patients and 15 healthy children were selected. The patient group had lower concentrations of IgG1 and IgG2 specific pneumococcal antibodies compared with healthy children, regardless of whether or not the total IgG2 concentration was low. The children with recurrent bronchitis showed a greater increase in IgG1 and IgG2 antibodies after immunisation than the controls. It is concluded that children with recurrent bronchitis show a decreased humoral immune response to pneumococcal type 3 polysaccharide antigen. This finding suggests that a defect in the humoral immune response against polysaccharide antigens is an important cause of recurrent bronchitis in childhood.     

Clinical correlates of response to pneumococcal immunization

OBJECTIVE: The inability to form antibodies to polysaccharide antigens may occur as a part of a more significant immunodeficiency or as an isolated defect. The latter has been reported in some children with recurrent upper and lower respiratory tract infections and evaluation of the responsiveness of such patients to polysaccharide antigens is indicated as part of their assessment. The present study evaluated the pattern of antibody responses of patients immunized with pneumococcal vaccine as part of the investigation of recurrent upper and lower respiratory tract infections to determine if any correlation exists between these responses and clinical presentation. METHODOLOGY: An analysis was performed of antibody responses to pneumococcal serotypes 3, 4 and 6 following immunization with a 23-valent vaccine in 42 children with normal IgG levels who were evaluated for recurrent infections. Antibody responses were assessed in relation to clinical features and the results of other immunological investigations. RESULTS: Of the 42 patients evaluated, 25 (59%) were responders to all serotypes tested. Failure to respond to serotype 3 alone was the least common pattern of non-response. Recurrent pneumonia, but not otitis media with discharge or chronic productive cough, was significantly associated with a lack of response to two or three serotypes. Failure to respond to serotype 3 alone or in combination with other serotypes was associated with more significant immune abnormalities. CONCLUSION: In a selected population of children with recurrent bacterial infections, pneumococcal serotype 3 is a strong immunogen. In this clinical group recurrent pneumonia is associated with a defect in response to multiple pneumococcal serotypes.     

Defective anti-polysaccharide antibody response in patients with ataxia-telangiectasia

The immunodeficiency in ataxia-telangiectasia (A-T) patients involves both cellular and humoral immunity; however, the specific antibody response is not well defined. Frequent respiratory infections are a prominent feature in A-T. Streptococcus pneumoniae is a common pathogen responsible for these infections. Defective B cell membrane signaling has been reported in A-T cells. These observations prompted us to investigate the B cell response to six frequently encountered pneumococcal serotypes in A-T patients. We found defective IgG antibody production to all studied serotypes (3, 6B, 7F, 14, 19F, and 23F) in 22 of 31 A-T patients (71%) who were immunized with a polyvalent pneumococcal vaccine. The impaired antibody responses did not correlate with either history of infection or serum immunoglobulin isotype levels. In addition, we did not observe any correlation between the pneumococcal antibody production and a specific mutation or level of intracellular ATM (ataxia-telangiectasia mutated) protein in lysates of lymphoblastoid cell lines from these patients. Our results suggest that the extent and severity of the recurrent sinopulmonary infections may depend not only on the immunological defects but also on other ATM-dependent physiological responses.     

Congenital microgastria and primary ciliary dyskinesia in a newborn with DiGeorge syndrome and 22q11.2 deletion.

BACKGROUND: Congenital microgastria is an uncommon result of impairment of normal foregut development and rotation during early embryology. Only about 50 cases have been reported in the literature, mostly associated with other multiple congenital anomalies. CASE REPORT: The case of a female newborn with multiple abnormalities, including cardiovascular malformation (type I truncus arteriosus communis) with deletion of chromosome 22q11.2, severe immunodeficiency (DiGeorge syndrome), microgastria, and impaired mucociliary function (primary ciliary dyskinesia) is reported. CONCLUSIONS: An association between the deletion of chromosome 22q11.2, microgastria, and impaired mucociliary function has never been observed before. A casual association seems highly unlikely and we can not exclude the possibility of genetic mechanisms that may link those syndromes.     

Safety of live viral vaccines in patients with chromosome 22q11.2 deletion syndrome (DiGeorge syndrome/velocardiofacial syndrome)

The package inserts of live viral vaccines include immunodeficiency as a contraindication. Nevertheless, patients with mild forms of immunodeficiency may benefit from vaccination. No published guidelines exist for the administration of these vaccines specifically to patients with chromosome 22q11.2 deletion syndrome. This syndrome is also sometimes called DiGeorge syndrome and is associated with thymic hypoplasia and diminished T-cell numbers and has a wide spectrum of phenotypic features that include cardiac anomalies, dysmorphic facial features, and hypocalcemia. Patients generally exhibit a mild to moderate decrement in T-cell numbers with preservation of T-cell function. The aims of this study were to investigate the incidence of side effects after live viral vaccine administration in a population with chromosome 22q11.2 deletion syndrome. The high frequency of this syndrome in the population (1:3000 children) mandates a greater understanding of the risks and benefits related to live viral vaccine administration. A retrospective analysis of vaccine adverse events was performed. The data acquisition form evaluated the frequency of live vaccine administration and the consequences of both vaccination and withholding the vaccine. Flow cytometric enumeration of T cells was performed as part of an immunologic evaluation. Thirty-two of 59 responders were vaccinated with the varicella vaccine. Only 9% of patients reported adverse events. However, 63% of unvaccinated children developed chickenpox. Comparison of patients who tolerated the vaccine with those who reported adverse events showed no statistically significant differences in current age (7 vs 5.7 years), age at vaccination (3 vs 2.5 years), or T-cell subset counts: CD3 (1951 vs 2083 cells/ microL), CD4 (1283 vs 1463 cells/ microL), and CD8 (530 vs 502 cells/ microL). Fifty-two of 59 responders were vaccinated with measles-mumps-rubella (MMR). Twelve (23%) of 52 reported mild side effects, including fever, rash, and constitutional symptoms. No severe adverse reactions were reported. No patient reported natural disease with measles, mumps, or rubella. There were no statistically significant differences between the T-cell counts in the vaccinated group reporting side effects versus the vaccinated group without side effects (mean CD3 counts: 1928 vs 1736 cells/ microL; CD4 counts: 1250 vs 1127 cells/ microL; and CD8 counts: 528 vs 483 cells/ microL). In our study, patients with chromosome 22q11.2 deletion syndrome had a similar incidence of adverse effects with varicella and MMR vaccines compared with that reported in the general population. All side effects were mild. However, in patients who did not receive the varicella vaccine, an overwhelming 63% contracted the disease. Patients who were not vaccinated against MMR did not develop natural disease. The data suggest that this is a cohort of patients with 22q11.2 deletion syndrome who have tolerated live viral vaccinations without evidence of significant side effects. A prospective study could address whether there are T-cell thresholds below which vaccination is unsafe; however, the information that we present suggests that vaccinating children with chromosome 22q11.2 deletion with live viral vaccines does not carry a significantly higher risk of adverse reactions compared with the general population, provided that they have no evidence of severe immunocompromise.     

Complete DiGeorge anomaly in the absence of neonatal hypocalcemia and velofacial and cardiac defects

We report an atypical case of complete DiGeorge (DG) anomaly that presented initially exclusively as severe combined immunodeficiency (SCID). The child had severe infections at diagnosis, in keeping with the SCID phenotype; however, normal lymphocyte counts and immunoglobulin levels were noted at admission, which delayed diagnosis. Importantly, the child presented without neonatal hypocalcemia or velofacial or cardiac abnormalities at the time of diagnosis, which masked underlying DG. This case outlines the difficulties in making the diagnosis of SCID in a timely manner and illustrates the variation in presentation of the 22q11.2 deletion syndrome. There should be a high index of suspicion for primary immunodeficiency among children with severe infections and, because management may vary, DG anomaly should be considered in the differential diagnosis of T- B+ natural killer+ SCID.     

Serum antibodies to pneumococcal C polysaccharide in children: response to acute pneumococcal otitis media or to vaccination

Immunoglobulin class-specific antibody responses to the pneumococcal C polysaccharide (CPS) and to the capsular polysaccharides of types 3, 6A, 18C and 19F were measured by enzyme-linked immunosorbent assay in the sera of children ages 6 months to 7 years. Twenty of these children had acute otitis media caused by pneumococci of type/group 3, 6, 18 or 19, whereas 20 received an injection of 14-valent pneumococcal capsular polysaccharide vaccine. Many of the children in both groups had large concentrations of IgG and/or IgM class anti-CPS antibodies in their first serum sample. Both the infection and the vaccine elicited anti-CPS responses in all three immunoglobulin classes, most notably IgA. The pneumococcal capsular polysaccharides used as antigens in the enzyme-linked immunosorbent assay were found to contain CPS in amounts ranging from less than 1 to 30%. As a result the enzyme-linked immunosorbent assay detected both anti-type-specific and anti-CPS antibodies. After elimination of the anti-CPS, type-specific pneumococcal antibodies were found only occasionally and in low concentrations in serum samples obtained in the acute phase of otitis or before vaccination. The infection induced homologous type-specific pneumococcal antibodies to varying degrees depending on the type: regularly to type 3; and fairly regularly to type 18C polysaccharide, but seldom to type 6 or 19. The pneumococcal vaccine induced type-specific antibodies to all four types measured, but the response to type 6A was poor.     

Evans syndrome in a patient with chromosome 22q11.2 deletion syndrome: a case report

One patient with a chromosome 22q11.2 deletion and Evans syndrome is reported in this paper. Microdeletions of 22q11.2 are the main etiology for DiGeorge syndrome, a disorder characterized by heart defects, immune deficiencies due to aplasia or hypoplasia of the thymus, and hypocalcemia. Evans syndrome refers to a hematological autoimmune disorder with autoimmune hemolytic anemia accompanied by immune thrombocytopenia. A wide range of autoimmune disorders have been described in DiGeorge syndrome and velocardiofacial syndrome, including one prior report of autoimmune hemolytic anemia and immune thrombocytopenia. The patient reported herein strengthens the association between the 22q11.2 deletion spectrum and Evans syndrome.     

Defining new guidelines for screening the 22q11.2 deletion based on a clinical and dysmorphologic evaluation of 194 individuals and review of the literature

The 22q11.2 deletion is the most frequent interstitial deletion in humans and presents a wide phenotypic spectrum, with over 180 clinical manifestations described. Distinct studies have detected frequencies of the deletion ranging from 0 % to 75 %, depending on the studied population and selection criteria adopted. Due to the lack of consensus in this matter, several studies have been conducted aiming to define which patients would be eligible for screening; however, the issue is still up for debate. In order to contribute to the delineation of possible clinical and dysmorphologic guidelines to optimize decision making in the clinical setting, 194 individuals with variable features of the 22q11.2 deletion syndromes (22q11.2DS) were evaluated. Group I, clinical suspicion of 22q11.2DS with palatal anomalies; Group II, clinical suspicion without palatal anomalies; Group III, cardiac malformations associated with the 22q11.2DS; and Group IV, juvenile-onset schizophrenia. Multiplex ligation-dependent probe amplification was used for screening the 22q11.2 deletion, which was detected in 45 patients (23.2 %), distributed as such: Group I, 35/101 (34.7 %); Group II, 4/18 (22.2 %); Group III, 6/52 (11.5 %); and Group IV, 0/23 (0 %). Clinical data were analyzed by frequency distribution and statistically. Based on the present results and on the review of the literature, we propose a set of guidelines for screening patients with distinct manifestations of the 22q11.2DS in order to maximize resources. In addition, we report the dysmorphic features which we found to be statistically correlated with the presence of the 22q11.2DS.     

The outcome of patients with unclassified hypogammaglobulinemia in early childhood

Symptomatic hypogammaglobulinemia in childhood may be the initial finding of primary immunodeficiency (PID) or may be due to delay in maturation of immunoglobulin synthesis. The aim of this study was to review the clinical and laboratory records of patients with unclassified hypogammaglobulinemia and to evaluate whether these children experience changes in serum immunoglobulin concentrations during long‐term followup and have an exact diagnosis in natural course of disease. We reviewed the data of 412 patients who were diagnosed as PID with symptomatic hypogammaglobulinemia. Thirty‐seven patients with hypogammaglobulinemia [19 males (51.4%) and 18 females (48.6%), with a followup of 34.1 ± 22.0 months] who were not classified according to European Society for Immunodeficiencies diagnostic criteria were included in this study. The mean age at the beginning of the symptoms was 21.4 ± 20.6 months and the mean age at admission was 51.5 ± 25.8 months. The commonest clinical presentations were recurrent upper (94.6%) and/or lower (40.5%) respiratory infections, urinary infection (27%) and gastroenteritis (10.8%). Percentage of consanguinity was 8%. Of the initial 37 patients, 18 (48.6%) spontaneously corrected their immunoglobulin abnormalities during followup. Clinical symptoms of these patients were also improved. IgG, IgA and IgM levels reached to normal levels at ages 62.5 ± 21.8, 72.0 ± 11.2, 55.2 ± 7.8 months, respectively. In remaining 19 patients with undefined/unclassified hypogammaglobulinemia, three partial IgA deficiency, seven IgG subclass deficiency, two selective IgM deficiency and two common variable immunodeficiency (CVID) were diagnosed by long‐term monitoring of immunoglobulin levels. Five (13.5%) of the 37 unclassified patients could not be exactly diagnosed while two of them might have a T‐cell defect and three of them still had low IgG and IgA levels but adequate antibody responses against vaccine antigens. In conclusion, it is important to monitor symptomatic patients with hypogammaglobulinemia periodically. Some children may spontaneously correct their immunoglobulin abnormalities not in the first 30 months of age, but during the first decade of life and some of them may have a severe PID like CVID.     

22q11.2 Deletions in Patients with Conotruncal Defects: Data from 1,610 Consecutive Cases

The 22q11.2 deletion syndrome is characterized by multiple congenital anomalies including conotruncal cardiac defects. Identifying the patient with a 22q11.2 deletion (22q11del) can be challenging because many extracardiac features become apparent later in life. We sought to better define the cardiac phenotype associated with a 22q11del to help direct genetic testing. 1,610 patients with conotruncal defects were sequentially tested for a 22q11del. The counts and frequencies of primary lesions and cardiac features were tabulated for those with and those without a 22q11del. Logistic regression models investigated cardiac features that predicted deletion status in tetralogy of Fallot (TOF). Deletion frequency varied by primary anatomic phenotype. Regardless of the cardiac diagnosis, a concurrent aortic arch anomaly (AAA) was strongly associated with deletion status [odds ratio (OR), 5.07; 95 % confidence interval (CI), 3.66–7.04]. In the TOF subset, the strongest predictor of deletion status was an AAA (OR, 3.14; 95 % CI 1.87–5.27; p < 0.001), followed by pulmonary valve atresia (OR, 2.03; 95 % CI 1.02–4.02; p = 0.04). Among those with double-outlet right ventricle and transposition of the great arteries, only those with an AAA had a 22q11del. However, 5 % of the patients with an isolated conoventricular ventricular septal defect and normal aortic arch anatomy had a 22q11del, whereas no one with an interrupted aortic arch type A had a 22q11del. A subset of patients with conotruncal defects are at risk for a 22q11del. A concurrent AAA increases the risk regardless of the intracardiac anatomy. These findings help to direct genetic screening for the 22q11.2 deletion syndrome in the cardiac patient.     

An adolescent with 22q11.2 deletion syndrome and multiple endocrinopathies

The endocrine abnormalities are common in patients with 22q11.2 deletion, and include hypocalcaemia due to primary hypoparathyroidism, short stature and thyroid dysfunction. We present a patient with delayed diagnosis of del22q11.2 who had multiple endocrine involvement and type 1 diabetes mellitus. A review is also made on the current knowledge of the endocrine manifestations described in patients with 22q11.2 deletion.     

15q11.2 proximal imbalances associated with a diverse array of neuropsychiatric disorders and mild dysmorphic features

ABSTRACT:: Deletion within the proximal region of chromosome 15q11.2 between breakpoints 1 and 2 (BP1-BP2) has been proposed to be a risk factor for intellectual disability, seizure, and schizophrenia. However, the clinical significance of its reciprocal duplication is not clearly defined yet. We evaluated 1654 consecutive pediatric patients with various neurological disorders by high-resolution microarray-based comparative genomic hybridization. We identified 21 patients carrying 15q11.2 BP1-BP2 deletion and 12 patients carrying 15q11.2 BP1-BP2 duplication in this cohort, which represent 1.27% (21/1,654) and 0.7% (12/1,654) of the patients analyzed, respectively. Approximately 87.5% of the patients carrying the deletion and 80% of the patients carrying the duplication have developmental delay or intellectual disability. Other recurrent clinical features in these patients include mild dysmorphic features, autistic spectrum disorders, and epilepsy. Our observations provide further evidence in favor of a strong association of 15q11.2 BP1-BP2 deletion with a variety of neuropsychiatric disorders. The diversity of clinical findings in these patients expands the phe-notypic spectrum of individuals carrying the deletion. In addition, possible etiological effects of 15q11.2 BP1-BP2 duplication in neuropsychiatric disorders are proposed.