DiGeorge syndrome presenting with palmoplantar pustules: Comparative analysis of serum IL-22, NETs and IL-8 with usual palmoplantar pustulosis.

DiGeorge syndrome, also known as 22q11.2 deletion syndrome, shows cellular immunodeficiency due to by thymic hypoplasia and hypocalcemia caused by hypoparathyroidism. It was reported that erythrodermic psoriasis occurred in a patient with 22q11 deletion syndrome. Here, we report the first case of DiGeorge syndrome presenting with a severe palmoplantar pustulosis (PPP)-like eruption with extra-palmoplantar lesions on the distal limbs. Given that PPP is a subtype of pustular psoriasis, the pustular eruption may be associated with DiGeorge syndrome. We measured serum levels of citrullinated histone H3 (CitH3), a representative marker of neutrophil extracellular traps, interleukin (IL)-8, and IL-22 and compared them with nine cases of typical PPP. In the PPP patients, the three markers were higher than in healthy subjects with significant correlations between CitH3 and IL-8/IL-22. In our patient, CitH3, IL-8, and IL-22 were also high, and IL-22 was remarkably elevated compared with the PPP patients. Our case suggests that a certain T cell abnormality associated with DiGeorge syndrome induces IL-22 overproduction, leading to the PPP-like eruption with extra- palmoplantar lesions.

Chromatin Modifications in 22q11.2 Deletion Syndrome.

PURPOSE: Chromosome 22q11.2 deletion syndrome is a common inborn error of immunity. The early consequences of thymic hypoplasia are low T cell numbers. Later in life, atopy, autoimmunity, inflammation, and evolving hypogammaglobulinemia can occur and the causes of these features are not understood. This study utilized an unbiased discovery approach to define alterations in histone modifications. Our goal was to identify durable chromatin changes that could influence cell behavior. METHODS: CD4 T cells and CD19 B cells underwent ChIP-seq analysis using antibodies to H3K4me3, H3K27ac, and H4ac. RNA effects were defined in CD4 T cells by RNA-seq. Serum cytokines were examined by Luminex. RESULTS: Histone marks of transcriptional activation at CD4 T cell promoters and enhancers were globally increased. The promoter activation signature had elements related to T cell activation and inflammation, concordant with effects seen in the transcriptome. B cells, in contrast, had a minimally altered epigenetic landscape in 22q11.2. Both cell types had an "edge" effect with markedly altered chromatin adjacent to the deletion. CONCLUSIONS: People with 22q11.2 deletion have altered CD4 T cell chromatin and a transcriptome concordant with the changes in the epigenome. These effects support a disease model where qualitative changes to T cells occur in addition to quantitative defects that have been well characterized. This study offers unique insight into qualitative differences in the T cells in 22q11.2 deletion, an aspect that has received limited attention.

Central 22q11.2 deletion (LCR22 B-D) in a fetus with severe fetal growth restriction and a mother with severe systemic lupus erythematosus: Further evidence of CRKL haploinsufficiency in the pathogenesis of 22q11.2 deletion syndrome.

22q11.2 deletion syndrome (22q11.2 DS, MIM #188400) is the most common chromosomal microdeletion with an incidence of 1 in 4000 live births. 22q11.2 DS patients present with varying penetrance and a broad phenotypic spectrum including dysmorphic features, congenital heart defects, hypoplastic thymus and T-cell deficiency, and hypocalcemia. The typical deletion spans 3 Mb between 4 large blocks of repetitive DNA, known as low copy repeats (LCRs), on chromosome 22 (LCR22) A and D. This deletion is found in ~85% of 22q11.2 DS patients, while only 4-5% have central LCR22B-D (1.5 Mb) and LCR22C-D (0.7 Mb) deletions. We report on a prenatally diagnosed, inherited case of central LCR22B-D 22q11.2 DS, born to a 22-year-old female with multiple autoimmune disorders. These include Sjogren's-syndrome-related antigen A (SSA+) severe systemic lupus erythematosus (SLE) with cutaneous and discoid components and seronegative antiphospholipid syndrome. Amniocentesis was performed due to fetal growth restriction (FGR). FISH with TUPLE1 (HIRA) probe was normal; however, chromosomal microarray identified a ~737 kb heterozygous loss between LCR22B-D. Subsequently, the same deletion was identified in the mother, which included CRKL and 19 other genes but excluded HIRA and TBX1, the typical candidate genes for 22q11.2DS pathogenesis. This case explores how loss of CRKL may contribute to immune dysregulation, as seen in the multiple severe autoimmune phenotypes of the mother, and FGR. Our experience confirms the importance of thorough workup in individuals with reduced penetrance of 22q11.2 DS features or atypical clinical presentations.

Platelet Dysfunction in Noonan and 22q11.2 Deletion Syndromes in Childhood.

INTRODUCTION: An underlying thrombocytopathy seems to be responsible for hemorrhagic symptoms in patients diagnosed with 22q11.2 deletion syndrome (22q11DS) or Noonan syndrome (NS). In 22q11DS, it is explained by a defect in the membrane glycoprotein (GP) complex Ib-V-IX. The cause of thrombocytopathy in NS remains unclear. AIM: The objective is to study the incidence of thrombocytopathy in pediatric patients diagnosed with 22q11DS or NS assessing the utility of ISTH-BAT questionnaire and laboratory techniques. MATERIALS AND METHODS: Prospective study between March and December 2018 in children (2-18 years old) diagnosed with 22q11DS or NS. Hemorrhagic symptoms using ISTH-BAT score, total cell blood count, platelet indices, PFA-200 closure times, and platelet aggregation were evaluated in all patients and membrane GP expression in 22q11DS patients. RESULTS: Nearly 70% of NS patients (n = 22) had a platelet aggregation defect without thrombocytopenia. A defect of platelet aggregation with adenosine diphosphate (ADP) and epinephrine was the most frequent pattern. A statistically significant inverse correlation between closure times and aggregation with arachidonic acid (p = 0.049, p = 0.043) and epinephrine (p = 0.021, p = 0.035), and ADP (p = 0.117, p = 0.05) was found. Total 5 out of 29 patients diagnosed with 22q11DS had macrothrombocytopenia; more noteworthy in older patients. Twenty-six patients showed an impairment in ristocetin-induced platelet aggregation that correlated with prolonged collagen/epinephrine (p = 0.034) and collagen/ADP (p = 0.01). A significant association between ISTH-BAT score >3 and closure times (p = 0.022, p = 0.002) and aggregation defect with ristocetin (p = 0.043) was also demonstrated. CONCLUSION: Most NS and 22q11DS patients show an impairment of platelet aggregation that correlates with closure times. In 22q11DS patients, these results were also related to hemorrhagic symptoms.

Exploring the potential association among sleep disturbances, cognitive impairments, and immune activation in 22q11.2 deletion syndrome.

22q11.2 deletion syndrome (22q11.DS) is a neurogenetic disorder caused by a microdeletion in chromosome 22. Its phenotype includes high rates of psychiatric disorders, immune system abnormalities, and cognitive impairments. We assessed the quality of sleep in 22q11.2DS and its potential link to inflammatory markers and cognitive deficits. Thirty-three 22q11.2DS individuals and 24 healthy controls were studied. Sleep parameters were assessed by the Pittsburgh sleep quality index (PSQI) questionnaire and correlated with serum cytokine levels and cognitive functioning, measured using the Penn computerized neurocognitive battery (CNB). The 22q11.2DS individuals had significantly worse sleep quality scores than the controls, unrelated to the psychiatric or physical comorbidities common to 22q11.2DS. Interleukin 6 levels were correlated with the overall score of the PSQI questionnaire for nonpsychotic 22q11.2DS participants only. Several domains of the CNB were associated with poorer sleep quality, suggesting that cognitive impairments in 22q11.2DS may be at least partially explained by poor sleep quality. Our findings confirm sleep impairments in individuals with 22q11.2DS, which might negatively affect their cognitive functioning, and corroborate a potential role of immunological pathways in the 22q11.2DS neuro-phenotype.

Heterozygous Mutations in TBX1 as a Cause of Isolated Hypoparathyroidism.

Context: Most cases of autosomal dominant isolated hypoparathyroidism are caused by gain-of-function mutations in CASR or GNA11 or dominant negative mutations in GCM2 or PTH. Objective: To identify the genetic etiology for dominantly transmitted isolated hypoparathyroidism in two multigenerational families with 14 affected family members. Methods: We performed whole exome sequencing of DNA from two families and examined the consequences of mutations by minigene splicing assay. Results: We discovered disease-causing mutations in both families. A splice-altering mutation in TBX1 (c.1009+1G>C) leading to skipping of exon 8 (101 bp) was identified in 10 affected family members and five unaffected subjects of family A, indicating reduced penetrance for this point mutation. In a second family from France (family B), we identified another splice-altering mutation (c.1009+2T>C) adjacent to the mutation identified in family A that results in skipping of the same exon; two subjects in family B had isolated hypoparathyroidism, whereas a third subject manifested the clinical triad of the 22q11.2 deletion syndrome, indicative of variable expressivity. Conclusions: We report evidence that heterozygous TBX1 mutations can cause isolated hypoparathyroidism. This study adds knowledge to the increasingly expanding list of causative and candidate genes in isolated hypoparathyroidism.

Newborn screening for severe combined immunodeficiency: Evaluation of a commercial T-cell receptor excision circle-based method in Victorian dried blood spots.

AIM: Severe combined immunodeficiency (SCID) is the most severe form of primary immunodeficiency and is fatal in infancy if untreated. As early diagnosis is associated with improved outcomes, SCID is an ideal condition to consider for inclusion in a newborn screening (NBS) programme in Australia. In this feasibility study, we evaluated the EnLite Neonatal TREC kit for detection of T-cell receptor excision circles (TRECs) from NBS dried blood spots for the identification of known SCID patients in Victoria. METHODS: TREC copies/µL were measured retrospectively in 14 children diagnosed with SCID or complete DiGeorge syndrome (CDGS) from 2005 to 2015 at the Royal Children's Hospital, Melbourne. In addition, TREC copies/µL were measured for 501 prospective de-identified NBS cards. RESULTS: Of 14 known SCID or CDGS samples, 11 were correctly identified as presumptive positive samples with low or undetectable TREC on duplicate testing. The remaining three samples also had low or undetectable TREC on duplicate testing but were considered invalid due to insufficient ß-actin DNA amplification. Of the 501 prospective NBS samples, none were identified as presumptive positive samples on duplicate testing. CONCLUSIONS: The EnLite Neonatal TREC kit correctly identified known SCID or CDGS patients as presumptive positive samples, and initial cut-offs for TREC and ß-actin in the Victorian NBS population were determined. A larger pilot study is required to confirm these proposed cut-offs and to evaluate the cost and implementation of this screening programme in Victoria, Australia. Overall, this study provides preliminary data to support the introduction of this assay to the NBS programme in Victoria.

Elevated Proinflammatory Markers in 22q11.2 Deletion Syndrome Are Associated With Psychosis and Cognitive Deficits.

OBJECTIVE: 22q11.2 deletion syndrome (22q11.2DS) is a neurogenetic disorder whose phenotype includes high rates of a schizophrenia-like psychotic disorder and immune system abnormalities. Thus, 22q11.2DS is an ideal model for studying the relationship between psychosis and inflammation. The aim of the present study was to identify inflammatory markers that may play a role in the pathophysiologic pathways associated with psychosis and cognitive deficits in 22q11.2DS. METHODS: Forty-nine individuals with 22q11.2DS (13 with psychotic disorders according to DSM-IV criteria and 36 without psychotic disorders) and 30 age- and sex-matched healthy controls underwent psychiatric and cognitive assessments at an outpatient clinic. Blood samples from all participants were analyzed for C-reactive protein (CRP), interleukin (IL)-6, IL-10, tumor necrosis factor alpha (TNFα), and IL-1 receptor antagonist levels. The study was conducted between August 2014 and September 2015. RESULTS: The 22q11.2DS participants had elevated levels of CRP (P = .004), IL-6 (P = .001), TNFα (P < .001), and IL-10 (P = .028) compared with controls. Furthermore, the psychotic 22q11.2DS participants had higher levels of IL-6 (P < .001) and IL-6/IL-10 ratio (used as an indicator for proinflammatory activation, P < .001) compared with the nonpsychotic 22q11.2DS individuals and controls. IL-6 levels and the IL-6/IL-10 ratio correlated with the severity of the cognitive deficits in the 22q11.2DS participants. CONCLUSIONS: Our preliminary findings indicate an involvement of inflammatory processes in the pathophysiology of psychosis and cognitive deficits in 22q11.2DS and are in line with the accumulating evidence for the role of neuroinflammation in nonsyndromic schizophrenia.

Graves' Disease in Pediatric and Elderly Patients with 22q11.2 Deletion Syndrome.

22q11.2 Deletion Syndrome (22qDS) is often complicated by autoimmune diseases. To clarify the causal relationship, we examined the lymphocyte subset distribution and the human leucocyte antigen (HLA) in two female patients (one child and an elderly) with Graves' disease (GD) and 22qDS. Thymus dysgenesis might have contributed to the T-cell imbalance and the lack of negative selection in both cases. Notably, HLA-DR14, a known risk factor for GD in Japanese individuals and the decreased regulatory T-cell numbers that were seen in the pediatric case, may affect the early onset of GD. Central and peripheral tolerance and Th1 cells appeared to be associated with the pathogenesis of GD in 22qDS.

Would mean platelet volume/platelet count ratio be used as a novel formula to predict 22q11.2 deletion syndrome?

BACKGROUND: The diagnosis of 22q11.2 deletion syndrome depends on a time-consuming and expensive method, fluorescence in situ hybridisation (FISH). OBJECTIVES: We aimed to determine new parameters which can aid for in the diagnosis of 22q11.2 deletion syndrome. METHODS: Twenty two patients with 22q11.2 or 10p13 deletion were evaluated retrospectively. RESULTS: Facial-dysmorphism and mental-motor retardation were detected in 100% of patients. Mean platelet (PLT) counts were lower (224,980 versus 354,000, p = 0.001), mean PLT volume (MPV) (9.95 versus 7.07, p = 0.002), and MPV/PLTx105 ratios (5.36 versus 2.08, p < 0.001) were higher in patients with 22q11.2 deletion compared with the control group. Area under the receiver-operator characteristic (ROC) curve was 0.864, sensitivity was 84.6%, specificity was 90.9%, positive predictive value (PPV) was 91.7%, and negative predictive value (NPV) was 83.3% when MPV was 8.6. Area under ROC curve was 0.864, sensitivity was 76.9%, specificity was 90.1%, PPV was 90.1%, and NPV was 76.3% when PLT was 265,500. Area under ROC curve was 0.906, sensitivity was 84.6%, specificity was 100%, PPV was 100%, and NPV was 84.6% when MPV/PLTx105 was 3.3. Expression of PLT surface markers which were not in the GPIb-V-IX receptor complex (CD61, CD41a) increased as the surface area increased, but markers which were in a complex (CD42a, CD42b) did not change. CONCLUSIONS: High MPV/PLT value can be a good predictor for the diagnosis of 22q11.2 deletion syndrome. We suggest that in patients with facial dysmorphism and retardation in neurodevelopmental milestones and if MPV≥8.6fl, MPV/PLTx105 ratio≥3.3 and PLT count ≤265,500/mm3, the patients should be tested by FISH analysis to confirm the 22q11.2 deletion. If there are no macrothrombocytes, the 10p13 deletion should be tested in suspected cases.

The role of COMT and plasma proline in the variable penetrance of autistic spectrum symptoms in 22q11.2 deletion syndrome.

This paper examines how COMT158 genotypes and plasma proline levels are associated with variable penetrance of social behavioural and social cognitive problems in 22q11.2 deletion syndrome (22q11DS). Severity of autistic spectrum symptoms of 45 participants with 22q11DS was assessed using the Autism Diagnostic Interview Revised. Face and facial emotion recognition was evaluated using standardized computer-based test-paradigms. Associations with COMT158 genotypes and proline levels were examined. High proline levels and poor face recognition in individuals with the COMTMET allele, and poor facial emotion recognition, explained almost 50% of the variance in severity of autism symptomatology in individuals with 22q11DS. High proline levels and a decreased capacity to break down dopamine as a result of the COMTMET variant are both relevant in the expression of the social phenotype in patients. This epistatic interaction effect between the COMT158 genotype and proline on the expression of social deficits in 22q11DS shows how factors other than the direct effects of the deletion itself can modulate the penetrance of associated cognitive and behavioural outcomes. These findings are not only relevant to our insight into 22q11DS, but also provide a model to better understand the phenomenon of variable penetrance in other pathogenic genetic variants.

Transcriptome Profiling of Peripheral Blood in 22q11.2 Deletion Syndrome Reveals Functional Pathways Related to Psychosis and Autism Spectrum Disorder.

BACKGROUND: 22q11.2 Deletion Syndrome (22q11DS) represents one of the greatest known genetic risk factors for the development of psychotic illness, and is also associated with high rates of autistic spectrum disorders (ASD) in childhood. We performed integrated genomic analyses of 22q11DS to identify genes and pathways related to specific phenotypes. METHODS: We used a high-resolution aCGH array to precisely characterize deletion breakpoints. Using peripheral blood, we examined differential expression (DE) and networks of co-expressed genes related to phenotypic variation within 22q11DS patients. Whole-genome transcriptional profiling was performed using Illumina Human HT-12 microarrays. Data mining techniques were used to validate our results against independent samples of both peripheral blood and brain tissue from idiopathic psychosis and ASD cases. RESULTS: Eighty-five percent of 22q11DS individuals (N = 39) carried the typical 3 Mb deletion, with significant variability in deletion characteristics in the remainder of the sample (N = 7). DE analysis and weighted gene co-expression network analysis (WGCNA) identified expression changes related to psychotic symptoms in patients, including a module of co-expressed genes which was associated with psychosis in 22q11DS and involved in pathways associated with transcriptional regulation. This module was enriched for brain-expressed genes, was not related to antipsychotic medication use, and significantly overlapped with transcriptional changes in idiopathic schizophrenia. In 22q11DS-ASD, both DE and WGCNA analyses implicated dysregulation of immune response pathways. The ASD-associated module showed significant overlap with genes previously associated with idiopathic ASD. CONCLUSION: These findings further support the use of peripheral tissue in the study of major mutational models of diseases affecting the brain, and point towards specific pathways dysregulated in 22q11DS carriers with psychosis and ASD.

Characteristics of 22q 11.2 deletion syndrome undiagnosed until adulthood: an example suggesting the importance of psychiatric manifestations.

Patients with chromosome 22q11.2 deletion syndrome (22q11.2DS) exhibit various combinations of signs and symptoms including facial dysmorphism, thymus absence, hypoparathyroidism, cellular immunodeficiency and cardiac abnormalities caused by microdeletion of chromosome 22q11.2. Most cases are diagnosed during post-natal cardiac evaluation, though some are diagnosed at later stages. We report the case of a 39-year-old man with 22q11.2DS presenting with seizure due to tardily manifested hypocalcaemia and anxiety disorder. Our experience suggests that 22q11.2DS patients lacking fatal or well-recognised manifestations such as cardiac defects, immunodeficiency and facial dysmorphism tend to survive without medical attention, and are therefore overlooked. Recognition of the age-related variance of the manifestations, and specifically of tardily manifested hypocalcaemia and psychiatric or developmental disorders as manifestations of 22q11.2DS in adulthood, is important for diagnosis and can also help us provide appropriate medical and psychosocial support for newly diagnosed 22q11.2DS patients in adolescence or adulthood and their families.

Neonatal Levels of T-cell Receptor Excision Circles (TREC) in Patients with 22q11.2 Deletion Syndrome and Later Disease Features.

PURPOSE: Newborns with severe T-cell lymphopenia, including those with 22q11.2 deletion syndrome (DS), have low numbers of T-cell receptor excision circles (TRECs). The aim of this study was to determine a possible correlation between neonatal TRECs in 22q11.2DS and the development of different phenotypes to elucidate the prognostic value of TREC in this disease. METHODS: In this national survey including 46 patients with 22q11.2DS born after 2005, TREC levels were determined using stored newborn screening blood spots on filter cards. Patients were grouped into quartiles according to their TREC values, except the two infants with thymus aplasia. RESULTS: The two patients with thymic aplasia had no detectable TREC. The rest had no severe clinical immunodeficiency. There was a significant correlation between low TRECs and the proportion of patients with CD3(+)CD4(+)T-cells below the 5th percentile of healthy infants (p = 0.027) as well as the proportion with an abnormal thymus feature either no thymus or remnant thymus as observed during heart surgery (p = 0.022). Significantly lower TRECs (p = 0.019) were found in patients with cardiac defects compared to no such defects. Patients within the lowest quartile of TREC values (<71 TRECs/µL, n = 11) had more frequent severe cardiac defects than the other quartiles (p = 0.010). Eight of these patients in the lowest quartile needed an operation/intervention within two weeks after birth or died because of a cardiac defect. CONCLUSION: The low TREC values not only correlate with decreased T-cell immunity, but also with the occurrence of heart defects in the patients.

Detection of fetal subchromosomal abnormalities by sequencing circulating cell-free DNA from maternal plasma.

BACKGROUND: The development of sequencing-based noninvasive prenatal testing (NIPT) has been largely focused on whole-chromosome aneuploidies (chromosomes 13, 18, 21, X, and Y). Collectively, they account for only 30% of all live births with a chromosome abnormality. Various structural chromosome changes, such as microdeletion/microduplication (MD) syndromes are more common but more challenging to detect. Recently, several publications have shown results on noninvasive detection of MDs by deep sequencing. These approaches demonstrated the proof of concept but are not economically feasible for large-scale clinical applications. METHODS: We present a novel approach that uses low-coverage whole genome sequencing (approximately 0.2×) to detect MDs genome wide without requiring prior knowledge of the event's location. We developed a normalization method to reduce sequencing noise. We then applied a statistical method to search for consistently increased or decreased regions. A decision tree was used to differentiate whole-chromosome events from MDs. RESULTS: We demonstrated via a simulation study that the sensitivity difference between our method and the theoretical limit was <5% for MDs ≥9 Mb. We tested the performance in a blinded study in which the MDs ranged from 3 to 40 Mb. In this study, our algorithm correctly identified 17 of 18 cases with MDs and 156 of 157 unaffected cases. CONCLUSIONS: The limit of detection for any given MD syndrome is constrained by 4 factors: fetal fraction, MD size, coverage, and biological and technical variability of the event region. Our algorithm takes these factors into account and achieved 94.4% sensitivity and 99.4% specificity.

Screening newborn blood spots for 22q11.2 deletion syndrome using multiplex droplet digital PCR.

BACKGROUND: The diagnosis of 22q11 deletion syndrome (22q11DS) is often delayed or missed due to the wide spectrum of clinical involvement ranging from mild to severe, often life-threatening conditions. A delayed diagnosis can lead to life-long health issues that could be ameliorated with early intervention and treatment. Owing to the high impact of 22q11DS on public health, propositions have been made to include 22q11DS in newborn screening panels; however, the method of choice for detecting 22q11DS, fluorescent in situ hybridization, requires specialized equipment and is cumbersome for most laboratories to implement as part of their routine screening. We sought to develop a new genetic screen for 22q11DS that is rapid, cost-effective, and easily used by laboratories currently performing newborn screening. METHODS: We evaluated the accuracy of multiplex droplet digital PCR (ddPCR) in the detection of copy number of 22q11DS by screening samples from 26 patients with 22q11DS blindly intermixed with 1096 blood spot cards from the general population (total n = 1122). RESULTS: Multiplex ddPCR correctly identified all 22q11DS samples and distinguished between 1.5- and 3-Mb deletions, suggesting the approach is sensitive and specific for the detection of 22q11DS. CONCLUSIONS: These data demonstrate the utility of multiplex ddPCR for large-scale population-based studies that screen for 22q11DS. The use of samples from blood spot cards suggests that this approach has promise for newborn screening of 22q11DS, and potentially for other microdeletion syndromes, for which early detection can positively impact clinical outcome for those affected.

Gastrointestinal involvement in patients affected with 22q11.2 deletion syndrome.

OBJECTIVE. Enteropathy is a very common feature in patients with primary immunodeficiencies. In patients with Del22 gastrointestinal (GI) alterations, including feeding disorders and congenital abnormalities have been often reported, mostly in the first year of life. MATERIAL AND METHODS. Aim of this monocentric study is to better define the GI involvement in a cohort of 26 patients affected with Del22 syndrome. Anamnestic information was retrospectively collected for each patient. Weight and height parameters at the time of the screening were recorded. Plasma levels of hemoglobin, iron, ferritin, albumin, total protein, calcium, phosphorus, transaminase levels, antigliadin (AGA) IgA and IgG, and antitissue transglutaminase (anti-TGase) titers were measured. RESULTS. A GI involvement was identified in the 58% of patients. The prominent problems were abdominal pain, vomiting, gastroesophageal reflux and chronic constipation. Weight deficiency, short stature and failure to thrive were reported in 54, 42, and 30% of the patients, respectively. The evidence of sideropenic anemia, in keeping with hypoproteinemia, impaired acid steatocrit or cellobiose/mannitol test suggested an abnormal intestinal permeability. In this cohort, a high prevalence of AGA IgA and IgG positivity was observed. Celiac disease (CD) was suspected in three patients, and in one of them confirmed by histology. In this patient, a long-lasting gluten-free diet failed to restore the intestinal architecture. CONCLUSIONS. In conclusion, GI involvement is a very common feature in Del22 patients. A better characterization of GI involvement would be very useful to improve the management of these patients.